Consumer Behavior Procter Gamble organization †Free Samples

Questions: 1.How Procter Gamble utilized corporate vision and vital promoting to re-taught the Chinese people group about Pampers? 2.The most significant thing for Chinese shoppers while purchasing dispensable nappy? 3.Procter and Gamble improved Pampers dispensable nappies for their future shopper? 4.Do you imagine that the decision of the Shunya Communication Group was a fitting decision by PG to advance Pampers in China, and if so why? 5.What parts of the Chinese culture could PG have utilized more to draw in its potential shopper when it propelled its Pampers procedure and by what method can the system have been improved? 6.How does key getting ready for PG contrast in the Chinese residential market to the universal market? Answers: Presentation PG or Procter and Gamble association was found in the hour of 1837, the association has flourished through changing money related cycles and colossal political and social changes. Procter and Gamble is an overall association that gives buy things in the regions of pharmaceuticals, singular consideration, cleaning supplies, and pet supplies. This depiction, nevertheless, ends up being logically distorted the more one explores the proportion of Procter and Gamble and also the degree of their tasks. Is contained more than brand names including Gillette, Bounty, Ivory, Old Spice, Pringles, Pampers and Tide and starting at now has in excess of 21 denotes that have close $1 Billion in yearly net arrangements. Representative and Gamble is a model for related thing contrasting characteristics all of Procter and Gamble's things advantage from a comparable dissemination to the equivalent or same sort of retail outlets and purchasers. Procter and Gamble are moreover by and to a great extent cre dited with having envisioned Mark organization. An extensive bit of PG's thriving can be credited to its upgrade, which begins from the progression of related things through either acquisitions or in-house fire up progress. PG's most present acquirement of the Gillette Corporation cost the association close $66 billion (Procter and Gamble Introduction, 2011). Procter and Gamble are moreover by and by pushing and making a direct to customer bargains online things store. Procter and Gamble said it is moving the store as a learning lab and not as a way to deal with evade the colossal box retailers like Target and Wal-Mart that sell its nuclear family and individual consideration brands to Internet clients. The electronic shopping site will be had and worked by PFS Web and exclusively feature Procter and Gamble things to clients. 1. In the underlying stage for the item propelled Procter and Gamble confronted a ton of issue in countering the difficulties that emitted during their items advancement. The fundamental test was to persuade the gatekeepers that the nappies are the best in offer in China. The principle system was to cause the watchmen to accept that they require the diapers at any expense for each mean. The diapers were a hit item in the western markets yet it was very hard to coordinate with the Chinese standers (FRAZIER, 2010). The children in China were generally not adjusted with the utilization this sort of material diapers. The fundamental purpose for such a gigantic market of PG in China is simply because of an individual known as Bruce Brown who is the man behind PGs 2 million promoting plan for China. After a lot of research and investigation of the buyer conduct in China, spoils is the best item in offer out running the entirety of its center rivals. The idea driving spoils advancement is s taggering. PGs China showcase is one fourth of the market spoils appreciates in USA, and it is normal that throughout next two years the market will have a development of progressively 40%. The achievement that PG appreciate in China controlled its CEO to take some antagonistic showcasing techniques. He made some game plan a year ago to contact all sides of the world and accomplish in excess of a billion customer through the span of five years (Riley, 2013). 2. PG come in the market of China in the period of 1998 through its Pampers item. After a couple of slips inferable from the low method of its fundamental thing and the obstruction of Chinese guards to the probability of pointless diapers, the market took off in the period of 2007 when PG showed its Golden Sleep battle that settling additional diapers to rest quality and updated kid change. As eagerness for irrelevant diapers has taken off or Display, relative maverick Kao has seen its bit of the general business in China flood, even while driving player PG and neighborhood affiliation Hengan International have lost ground and the Chinese requiring for Marries drove a for all intents and purposes triple enlargement in points of interest at Kao's Human Health Care Business between in 2012-2015 (Suzuki, 2016). The yearning for upmarket things is liberally clear among the making salaried class in China, and it is breathing new life into the proposals of different Western brands, the dia per wars appear, the model goes past the extravagance markets. PG started the trivial diaper promote in China; it has kept focusing on the mass buyer, dependent upon near to creation to make chop down evaluated diapers By division, Kao has concentrated on the unmatched distinguishing strength. With its touted superabsorbent polymer progression, moreover, the Made in Japan stamp, which appears to ensure validness the Marries diaper has changed into a pined for the brand among better quality customers. Without a doubt, a typical over 88% of Kao's business began from premium things, versus over 23% for PG and over 39% for Unicharm (Reingold, 2016). 3. The association delights customers through the viable progression of things, upgrades the regular activity, makes social obligations programs, urges agents to be secured, and cause accomplices to be responsible for shaping the association's future. Spoil, the greatest brand of diapers, which can keep their kids dry, great, secured and open to in the midst of their playing and resting time with the objective which watchmen could be reassured about their youths. The association is at no time later on focusing basically on youngsters has wandered into concentrating on the two babies and pregnant ladies. Spoil is concentrating on pregnant ladies, kids and infants, and preschoolers and little children. For those they are enthusiastic about picking ensured and shocking diapers with minimal size, watchmen who have starting at now had babies, they are excitement for driest, mildest, and most unstable diapers infant youngsters. Guardians of preschoolers and babies, they are busy with great er evaluated pleasing diapers and besides getting ready jeans so they could teach their kids can create mastery (Reingold, 2016). To satisfy the prerequisites and eagerness of the customer. Spoil conveyed driest, mildest, generally pleasant and fragile diapers with an alternate measure so watchmen could pick what they need considering the stages their kids in. Spoil also give planning pants to a part of the little children and the entirety of the preschoolers in order to help those children who r during the time spent lavatory getting ready. On the other hand, the association is centered around making green items and created life cycle reusable and nonessential diapers remembering the ultimate objective to deal with the purchaser's concern. 4. An expendable diaper, unimportant thing in West, fundamentally wasn't a touch of the social standard in the Chinese nursery. Infants wore surface diapers, or a noteworthy piece of the time, no diaper by any techniques. In addition, Bruce Brown, who's director of PG's more than $1.5 billion spending course of action of RD, is the explanation China appeared and still shows such a gigantic open gateway. Today, taking after quite a while of concentrated examination and many blunders, Pampers is offering diaper in China and the Connotation, from different points of view, is basically beginning there. The Shunya Communication Group was a proper decision by PG to advance Pampers in China (Frazier, 2010). The diaper display in China is affecting. It remains at around $1.3 billion unevenly a section the navigate of the U.S. advance and is predicted to wind up obviously in excess of 39 percent the going with couple of years, as appeared by examine firm Data screen. PG achievement in China h as helped CEO Bob McDonald normal not many striking goals. Past October, he put out a strategy to join close to 1 billion clients all through the going with around five years by advancing the association signify all through a touch of the humblest turns of the world. By what methodology will PG technique do that? To get information, essentially search the manner in which it split and to a colossal degree made the Chinas commercial center for trivial diapers. Right when the association initially moved Pampers in China in 1998, the exertion tumbled. Instead of stirring up an entrancing thing for the commercial center, a lower-quality translation made by PG of European and U.S., erroneously enduring that guards get them on the off chance that they enough horrible. It didn't exertion, Brown says. It didn't bolster which group of China had continually become along OK missing of unimportant diapers. There, potty game plan a great part of the time starts as before schedule a half year, and young people wear which are magnificent open groin pants which let them short and mitigate themselves in zones which is open. Remains pitch wasn't convincing individuals to have a go at something new nor were basically the thing (Frazier, 2010). We allocated the affectability in the prior changes, told Kelly Anchrum, an authority of generally speaking infant mind, outside relations, and reasonableness. It took a plasticky vibe. It took us quick to understand which delicate quality was tantamount as central to mums in a creation commercial center. 5. Diapers of PG's absolutely reframed the diaper grouping in China, and in doing as such made gigantic improvement for the classific

Strategic Business Unit free essay sample

A Strategic Business Unit (SBU) is the point at which a unit contains at least one items having a typical market base whose administrator has total duty regarding incorporating all capacity in to a technique against a recognizable contender. A SBU is made out of an item or product offerings having recognizable freedom from different items or product offerings in term of rivalry, costs, substitutability of item, style/quality, and effect of item withdrawal. (Kendrick, 2009) Sometimes a division in an organization may have at least two SBUs. Body The item advertise examination of the 2012 Chevy Silverado 2500HD LTZ Series is: A 4-wheel drive pickup truck with group taxi standard box with four entryways. It has a most extreme torque of 765 lbs/ft and payload of 4212 lbs. It additionally has a bundle arrangement and calfskin seats, with warmed and cooling alternatives. Likewise has an upgrade execution on the Tow/Haul mode and a decision of having a Duramax 6. We will compose a custom article test on Key Business Unit or on the other hand any comparable point explicitly for you Don't WasteYour Time Recruit WRITER Just 13.90/page 6L Turbo-Diesel and Allison Transmission or a 6. 0 L V8 Engine with Flex fuel capacity. It has a 36 gallon tank and when utilizing Duramax motor, it presents to 680 roadway miles. Its innovation has the On-star work with auto-start remote access, a Siriux XM Satellite Radio, back vision camera, Bluetooth Wireless Technology and USB Port for your MP3 player. Ultimately, it has Stabilitrak and a Diesel Exhaust Braking System. 1. Their essential rivals are different trucks that have comparative capacities and innovation. A portion of the trucks out there like the GMC Sierra 2500, Toyota Tundra, Ford F250, Nissan Titan and the Dodge Ram Truck. All these truck have comparative devices and innovation, yet what truly concerns the clients, is obviously, the value, the MPG on parkway and avenues, the strength and additionally torque and the towing limit. As per US News Magazine truck investigation, the best truck is right now the Ford Heavy Duty and afterward the Chevrolet 2500HD. 2. The objective market for the item is normally guys with development employments or who likes to tow and likes stacking limit of a truck. I, as well, am an objective client for this, and I need one so I can stack anything in the back and take it with me. I likewise like the torque and the pull of the trucks. I surmise you can say it’s a masculine sort of thing. Be that as it may, I do see a few females like to possess one, possibly on the grounds that they are from the open country or something. More or less, I really accept the objective market would be rustic regions with farmlands. 3. The item is situated in the market to contend with different contenders. Chevy shows extraordinary ads of their abilities and has been advertising the strength of their trucks. They use insights and estimation of how they can perform. The picture it sells is provocative as it were, on the grounds that it looks so spotless and satisfactory. They have various bundles to look over, similar to diesel or gas, 4WD or 2WD, the sorts of seats and amusement bundles. The cost is somewhat steep, however accompanies the quality and a multi year or 100,000 miles guarantee. It is been sold wherever in the states and urban communities. Hell it very well may be sold in American Samoa and various pieces of the world. Its circulation is worldwide and verily accessible. As I would like to think on the off chance that they are fruitful in the market world, I would say as much. Write in third individual †¦ give your thinking yet don’t allude to yourself and afterward back up your focuses with examine. They are positioned second on the top position trucks by US News. It may be higher in different nations. However, I accept they are getting the item sold in various spots and their plugs have worked admirably in causing the crowd to trust in their item. The item in being situated as the best truck on the planet, and it has the US work and sweat in building it to be the hardest truck there is. It constructs the American economy and it makes employments for America. The main outside impact I can think off would be charges and the manner in which individuals consider American trucks versus their own. I have uncles that think Japanese vehicles and trucks are preferable and last longer over American cars. They purchase reason for motor quality and durable. Americans get it reason for wellbeing and how intense it is if there should be an occurrence of a mishap. That is the thing that individuals accept. End The main effect that I can consider for the client to have is it is possible that they have a decent item or they don’t. Chevy items are acceptable items and most Americans will be extraordinary upbeat in having a Chevy or an American item. Some may have issues, however Chevy will continually ready to support anybody. I own a 2007 Chevy Suburban, and I had a few issues with it for its innovation bundles that prompted some oil issues. My guarantee was out, yet had the option to persuade General Motors to help pay for the issue. The client support will consistently be there for American Products. You had some great data. Make certain to let â€Å"you† well enough alone however. References: Kendrick, T. , (2009) Identifying and Managing Project Risk, fundamental instruments for disappointment sealing your task, second Edition, New York, NY: AMACOM.

CPW Day 2

CPW Day 2 Another insane (in a good way) day! Got to MIT early; checked in with my fellow admissions peeps. Not bound to the Reg Desk today, I made the most of my time attending events and meeting prefrosh. Started with the Student Life Learning Panel followup sessions. Had lunch with Mootmom. Went back to my office for the first time in 2 days; checked email. Akash Erin stopped by and we stalked people using the satellite feature of Google Maps for an hour or so. Met up with Lorelle and headed to the BSU Lounge in Walker; met some awesome people. Went to Senior Haus just in time to see 6000 bouncy balls thrown off the roof. Had some fun with said balls. Back to the BSU Lounge to hear AMAZING live jazz and eat Redbones for dinner. From there I headed to the Mr/Miss MIT pageant in time to see the winners crowned. At last Lorelle and I packed up the computers in La Sala and headed back to 3-107. Note to Caltech students: the note you left in our office, informing us of this, has made its way to, um, the right people. Not that I know anything about this. What? What note? What are you talking about? P.S. Can I just tell you all how much the prefrosh ROCK? Todays pics are below

Financial Advice For Robin Banks - 1303 Words

Mr Turvey, Accounting Financial Advice for Robin Banks Term 4, Personal Finance NEBAUER, Emma 11/18/2016 INTRODUCTION Personal finance is the management of how a family or individual obtains, budgets, saves and spends economic income over time, taking into account various financial risks and future life events (University, 2016). The importance of managing your finances comes down to what life you wish to live. By setting goals, and meeting them, will allow for positive finances. To best advance personal finances an individual could embark on investment options. An investment is the process of committing money, or capital, into an endeavour with the expectation of receiving additional income, or profit (Investopeida, 2016). This means that the investor is simply making their money work for them. It allows your money to go further than what you can personally earn for yourself; it expands the income that is coming in. The purpose of this report is to provide recommendations that will allow the client to meet and/or exceed their financial goals. This is to be represented through a discussion of relevant financial strategies - including those of investment options - the client’s goals, and the management of the risks involved with the client’s requests. CASE STUDY The client, Robin Banks, has approached Turvey Financial Advisors in order to seek advice on how she should plan for her financial future. Ms Banks is a 55 year old retiree, who upon her husband’s passingShow MoreRelatedCareer Analysis : My Career Essay1804 Words   |  8 Pagescorporate, industrial, financial and governmental communities around the world in a wide range of high-profile transactions, regulatory matters, and litigation and controversy issues.† Skadden’s clients include â€Å"a variety of small, entrepreneurial companies to a substantial number of the 500 largest U.S. corporations and many of the leading global companies.† The firm has â€Å"represented numerous governments, many of the largest banks (including virtually all of the leading investment banks), and major insuranceRead MoreMy Career Aspirations : A Case Essay2136 Words   |  9 Pagescorporate, industrial, financial and governmental communities around the world in a wide range of high-profile transactions, regulatory matters, and litigation and controversy issues.† Skadden’s clients include â€Å"a variety of small, entrepreneurial companies to a substantial number of the 500 largest U.S. corporations and many of the leading global companies.† The firm has â€Å"represented numerous governments, many of the largest banks (including virtually all of the leading investment banks), and major insuranceRead MoreBusiness Ethics : Australian And New Zealand Banking Group2923 Words   |  12 Pagesadopted by companies that support social and environmental welfare. 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The Effects Of Sleep Deprivation On College Students

Although acquiring the basic amount of sleep seems to be an easy task, college students are struggling to snag even a couple hours of sleep, thus significantly affecting their four domains of development during a crucial developmental period in their lives. College students are going through the development period, Emerging Adulthood, which is from the ages of 18 to 25 years old. During this period of time, adolescents tend to focus on their self-development and discover their identity and the four developmental domains are evolving (Grusec Hastings, 2008). The four domains are: Cognitive, Social, Emotional, and Physical. These domains are significantly affected by sleep deprivation, which is the condition of not having the right amount of sleep. Students are unable to focus on their academics, are unable to socialize, cannot handle their emotions, and their health begins to deteriorate. Sleep deprivation is becoming a major problem in the country and is affecting college students, who are going through an essential time in their lives for which they need to be in their shape. Throughout the nation, 70 million Americans are noted to have difficulties sleeping because of sleep disorders, which is roughly 23 percent of the national population (Gaultney, 2010). With sleep deprivation on the rise for students in universities, many adolescents’ four developmental domains are not developing properly. This paper will address the ways through which sleep deprivation isShow MoreRelatedThe Effects Of Sleep Deprivation On College Students Essay1319 Words   |  6 Pages Sleep deprivation is a frequent obstacle that many college students in America face. Insomnia in college students can have an immense impact on psychological and physical health, which greatly influence academic success. Research shows that 70% of college students qualify as sleep deprived. Sleep deprivation has also been linked with several diseases/disorders, including: depression, anxiety , and obesity. Our research question investigated how sleep deprivation in college students affectsRead MoreThe Effects Of Sleep Deprivation On College Students987 Words   |  4 PagesIntroduction Sleep is an incredibly important physiological action that functions as a period of growth, repair, rest, and relaxation for the human body (â€Å"Sleep,† 2015). As a population, college students are notorious for their skewed sleep patterns and their overall lack of getting the sufficient number of hours of sleep they need to perform optimally in school. Cramming the night before exams by pulling an â€Å"all-nighter† as well as the overall excessive number of distractions that present themselvesRead MoreThe Effects Of Sleep Deprivation On College Students908 Words   |  4 PagesCauses of Sleep Deprivation Insufficient and irregular sleep has been rated the top impediment to college students’ academic performance (Ye, Johnson, Keane, Manasia, Gregas, 2015). Although it is documented that for centuries students’ academic performance has been negatively affected by sleep disturbance, college students continue to have irregular sleep schedule and undergo self-imposed sleep deprivation. Sleep deprivation in college-age students tend to occur for multiple different reasons. SomeRead MoreEffects Of Sleep Deprivation On College Students1587 Words   |  7 PagesA great deal of students experience issues related to sleep when coming to college. These issues in sleep can be related to stress, going out and coming home late, or difficulties in adjusting to the college life. There are many ways college students are able to seek help for their difficulties in sleep. Sleep deprivation cannot only cause fatigue but also health issues such as a weakened immune system. College is said t o be one of the best times of someone’s life, but with sleep difficulties itRead MoreThe Effects Of Sleep Deprivation On College Students1448 Words   |  6 Pagesyou haven’t answered half of the questions as the professor exclaims, â€Å"Time’s up!† Sleep deprivation is a reoccurring issue on college campuses. Many students are unaware of the effects of sleep deprivation, because they believe that they are invincible and that they don’t need any sleep to function throughout the day. We should become aware of the mental and physical effects of sleep deprivation in college students, because by becoming aware of the issues, solutions can be established to reduce theRead MoreThe Effects Of Sleep Deprivation Among College Students3363 Words   |  14 Pages The Effects of Sleep Deprivation among College Students: A Psychological and Sociological Approach Integrative Project: Final Submission Synthia Paramathypathy Marianopolis College Sleep plays a major role in people s lives. Evidence has shown that enough sleep promotes good health and well-being (Ojikutu, R. 2010). It plays a key role in maintaining a healthy brain function,in helping to establish emotional well-being, and in improving overall health since it repairs the heart and bloodRead MoreThe Effect Of Sleep Deprivation On Academic Performance Of College Students Essay2242 Words   |  9 PagesThe Effect of Sleep Deprivation on the Academic Performance of College Students Sleep is something that every human experiences nearly every night. It is essential for achieving personal wellness, similar to how a nutritious diet and exercise are needed in order to be healthy. However, the stereotype of college students sometimes staying awake extremely late at night in order to finish their assignments still persists. This is a very unhealthy lifestyle choice if it is done repeatedly. In order forRead MoreSleep Deprivation Persuasive Speech1577 Words   |  7 PagesSpeech for Students’ Chronic Sleep Deprivation Introduction: A. Attention Getting Opening: Over the past ten to twenty years, academic demands placed upon college students have increased significantly, this has lead to an increase in workload and amount of time needed to study for a specific course. Today, college students represent the most sleep-deprived division of the population in the U.S. (Sleep and Memory). According to Gayla Martindale, 63% percent of the students who attend college do notRead MoreSleep Deprivation Essay1183 Words   |  5 PagesSleep is a necessity that people require to live a healthy lifestyle, and to partake in daily activities. Sleep is something that improves concentration, physical health, and provides energy. Steve Jobs once said, â€Å"For you to sleep well at night, the aesthetic, the quality, has to be carried all the way through.† Steve Jobs is proclaiming that to receive the full benefits of sleep, people must sleep the recommended hours. College students continue to undergo a lack of sleep as they persist throughRead MoreSleep Deprived College Students ( All Nighters )1556 Words   |  7 PagesAlyssa Arce Comm 150 Professor Matos January 25, 2016 Sleep Deprived College Students (All-Nighters) I. Intro a. Attention Getter: The famous â€Å"all-nighter†, where college students stay up all night studying, and preparing for a midterm, or even a final, in hopes to get an A. As a class we’ve all probably did an all-nighter once in our academic career to obtain the grades we want. However, according to ABC news, an article by Gillan Mohney, published in 2015, states that a person with blood-alcohol The Effects Of Sleep Deprivation On College Students Causes of Sleep Deprivation Insufficient and irregular sleep has been rated the top impediment to college students’ academic performance (Ye, Johnson, Keane, Manasia, Gregas, 2015). Although it is documented that for centuries students’ academic performance has been negatively affected by sleep disturbance, college students continue to have irregular sleep schedule and undergo self-imposed sleep deprivation. Sleep deprivation in college-age students tend to occur for multiple different reasons. Some of the factors that affect college students’ sleeping habits include late-night activities, work overload, noisy living conditions, inconsistently early-morning classes, and circadian rhythm imbalance (Bubolz et al, 2009). While some of these reasons are physiological, the behavioral components is extremely problematic on college campuses (Hershner, Chervin, 2014). This section will examine some of the causes of total and partial sleep deprivation as it relates to some common behaviors of colleg e students. Inadequate Sleep Hygiene Many college students suffer from sleep deprivation due to poor sleep behaviors. Sleep hygiene, behaviors that are conducive to restorative sleep, is often lacking in college students (Marhefka, 2011). Some of the behaviors that most college students demonstrate that promote inadequate sleep hygiene are irregular sleep-wake schedule, lack of a quiet sleep environment, consumption of caffeine after lunch time, napping for an extended period, andShow MoreRelatedThe Effects Of Sleep Deprivation On College Students1217 Words   |  5 Pages Although acquiring the basic amount of sleep seems to be an easy task, college students are struggling to snag even a couple hours of sleep, thus significantly affecting their four domains of development during a crucial developmental period in their lives. College students are going through the development period, Emerging Adulthood, which is from the ages of 18 to 25 years old. During this period of time, adolescents tend to focus on their self-development and discover their identity and the fourRead MoreThe Effects Of Sleep Deprivation On College Students Essay1319 Words   |  6 Pages Sleep deprivation is a frequent obstacle that many college students in America face. Insomnia in college students can have an immense impact on psychological and physical health, which greatly influence academic success. Research shows that 70% of college students qualify as sleep deprived. Sleep deprivation has also been linked with several diseases/disorders, including: depression, anxiety , and obesity. Our research question investigated how sleep deprivation in college students affectsRead MoreThe Effects Of Sleep Deprivation On College Students987 Words   |  4 PagesIntroduction Sleep is an incredibly important physiological action that functions as a period of growth, repair, rest, and relaxation for the human body (â€Å"Sleep,† 2015). As a population, college students are notorious for their skewed sleep patterns and their overall lack of getting the sufficient number of hours of sleep they need to perform optimally in school. Cramming the night before exams by pulling an â€Å"all-nighter† as well as the overall excessive number of distractions that present themselvesRead MoreEffects Of Sleep Deprivation On College Students1587 Words   |  7 PagesA great deal of students experience issues related to sleep when coming to college. These issues in sleep can be related to stress, going out and coming home late, or difficulties in adjusting to the college life. There are many ways college students are able to seek help for their difficulties in sleep. Sleep deprivation cannot only cause fatigue but also health issues such as a weakened immu ne system. College is said to be one of the best times of someone’s life, but with sleep difficulties itRead MoreThe Effects Of Sleep Deprivation On College Students1448 Words   |  6 Pagesyou haven’t answered half of the questions as the professor exclaims, â€Å"Time’s up!† Sleep deprivation is a reoccurring issue on college campuses. Many students are unaware of the effects of sleep deprivation, because they believe that they are invincible and that they don’t need any sleep to function throughout the day. We should become aware of the mental and physical effects of sleep deprivation in college students, because by becoming aware of the issues, solutions can be established to reduce theRead MoreThe Effects Of Sleep Deprivation Among College Students3363 Words   |  14 Pages The Effects of Sleep Deprivation among College Students: A Psychological and Sociological Approach Integrative Project: Final Submission Synthia Paramathypathy Marianopolis College Sleep plays a major role in people s lives. Evidence has shown that enough sleep promotes good health and well-being (Ojikutu, R. 2010). It plays a key role in maintaining a healthy brain function,in helping to establish emotional well-being, and in improving overall health since it repairs the heart and bloodRead MoreThe Effect Of Sleep Deprivation On Academic Performance Of College Students Essay2242 Words   |  9 PagesThe Effect of Sleep Deprivation on the Academic Performance of College Students Sleep is something that every human experiences nearly every night. It is essential for achieving personal wellness, similar to how a nutritious diet and exercise are needed in order to be healthy. However, the stereotype of college students sometimes staying awake extremely late at night in order to finish their assignments still persists. This is a very unhealthy lifestyle choice if it is done repeatedly. In order forRead MoreSleep Deprivation Persuasive Speech1577 Words   |  7 PagesSpeech for Students’ Chronic Sleep Deprivation Introduction: A. Attention Getting Opening: Over the past ten to twenty years, academic demands placed upon college students have increased significantly, this has lead to an increase in workload and amount of time needed to study for a specific course. Today, college students represent the most sleep-deprived division of the population in the U.S. (Sleep and Memory). According to Gayla Martindale, 63% percent of the students who attend college do notRead MoreSleep Deprivation Essay1183 Words   |  5 PagesSleep is a necessity that people require to live a healthy lifestyle, and to partake in daily activities. Sleep is something that improves concentration, physical health, and provides energy. Steve Jobs once said, â€Å"For you to sleep well at night, the aesthetic, the quality, has to be carried all the way through.† Steve Jobs is proclaiming that to receive the full benefits of sleep, people must sleep the recommended hours. College students continue to undergo a lack of sleep as they persist throughRead MoreSleep Deprived College Students ( All Nighters )1556 Words   |  7 PagesAlyssa Arce Comm 150 Professor Matos January 25, 2016 Sleep Deprived College Students (All-Nighters) I. Intro a. Attention Getter: The famous â€Å"all-nighter†, where college students stay up all night studying, and preparing for a midterm, or even a final, in hopes to get an A. As a class we’ve all probably did an all-nighter once in our academic career to obtain the grades we want. However, according to ABC news, an article by Gillan Mohney, published in 2015, states that a person with blood-alcohol

MEG A comparison with Other Functional Neuroimaging Techniques Free Essays

string(48) " discipline has traditionally been linked with\." Understanding is important to development of more complex procedure and ensuring efficiency in any area of operations. One of the tools used to develop a proper understanding and therefore diagnosis of a situation is the image of the situation. Sciences, technology, medicine and engineering all need images to be able to develop structures and operate efficiently. We will write a custom essay sample on MEG: A comparison with Other Functional Neuroimaging Techniques or any similar topic only for you Order Now In neuroscience, the development of an image of inner brain tissues is important to developing an understanding of a situation as it really is and therefore coming up with proper diagnostic and management approaches that will ensure the situation is addressed as it should. Life being what it is there are a number of choices that can be made in the approach that will be used for imaging. Each of these approaches has significant advantage and disadvantages and an understanding of the differences is important in making a decision on which one is best applicable depending on the parameters that define a condition (Kretschmann, Weinrich, 2003). MEG is one of the most common imaging techniques and the development of an understanding of the differences that it exhibits relative to others is important to its use. Advantages. Magnetoencephalography (MEG) implements a system where magnetic fields are produced by the aid of electric activity in the brain through use of highly sensitive devices. MEG which is common in research situation and clinical settings is one of the most commonly used approaches to neuroimaging. Surgeons have especially found MEG important in localising pathologies and researchers have used it in determining the various functions of parts of the brain, neurofeedback and in many other activities relating to the central nervous system. Many of the advantages of MEG are a result of its nature and principles that it applies in operations. Compared to functional imaging techniques like EEG, IMG has a number of key features that makes it more desirable; these are often considered in determining what neuroimaging technique will be applicable in either research or clinical situations (Holodny, 2008). MEG implements a system where the functions of the brain are directly measured. The main reason as to why imaging is necessary is to ensure a proper understanding of the state that the brain is and getting direct measures of the function is important and reduces the chance of error. Functional approaches like fMRI and SPECT use what can be best describes as functional measures to determine the state that the brain is in. Functional approaches which use variables that depict brain metabolisms to determine the functioning of the brain can be quite misleading for there are a number of variables that will have to be considered under such approaches. Moreover, errors can occur in translation of the metabolism variables to those that depict the state of the brain (Hillary, DeLuca, 2007). When developing an image the clarity of the image that will be developed is important. In neuroscience and many other areas where imaging has to be done in an environment that is highly controlled the ability to develop clear temporal images is important (Anschel, Mazumdar, Romanelli, 2007). This is due to the nature of the brain which requires low exposure to external activities and thus the idea of testing or imaging is in fact risky to the brain. MEG is considered to be an approach that has one of the highest temporal resolution. Events that have a time scale of milliseconds can be resolved accurately. Functional approaches like SPECT have much longer time scales and therefore the resolution of activities and development of a clear picture of the state that the brain is in is not as easy in such methods. It is worth noting that the brain being the centre of the nervous system is important and has a number of activities or events that occur within any given instant. The high resolution provided by MEG comes in handy and is important in capturing such events is therefore a better diagnostic tool in assessing the functionality of the brain inn consideration of the nature of the brain. In addition to the excellent temporal resolution, MEG has high levels of spatial resolution in that sources or objects can be located with millimetre precision. The brain is a small organ and it is one of the busiest in the human person. Information about the brain should be clear and precise; the high levels of precision that MEG has comes in handy and is important in coming up with clear accurate information on the performance of the brain. Neuroimaging is considered one of the most frightening event by people outside the medical fraternity. One reason as to why this is so is the invasive techniques used by functional imaging approaches. Isotopes and exposure to ray and magnetic field are used in other functional approaches and this is not only scary but also increases the health risks associated with neuroimaging and reduces the frequency of imaging allowed. MEG is unlike these functional techniques in this aspect in that EMG employs a system that is non-invasive. These property gives it an edge over other sin that it is even possible for children and infants to be studied repeatedly. Experts in neuroimaging and science are of the view that the reason as to why MEG has been widely adopted is its ability to be used alongside other approaches as it adds on to the picture to develop a clear understanding of the brain (Martin, Caramazza, 2003). While no one can dispute this fact practical application of MEG is quite easy as compared to functional approaches which could have also played a role in its development. Technology and the employment of aid in imaging are aimed at easing understanding of the brain functionalities (Gazzaniga, Bizzi, 2004). The ease that comes with the use of MEG is important and could be an avenue through which future generations use to reduce the complexity that neuroscience as a discipline has traditionally been linked with. You read "MEG: A comparison with Other Functional Neuroimaging Techniques" in category "Papers" The approach implemented by MEG makes it possible for its application in a variety of brain imaging processes. Sensory, language and memory cortex can all be imaged by use of MEG. An approach that is adaptable to multiple conditions is far much better that the ones that display low level of adaptability. This ability reduces the need to conduct multiple tests on individuals and therefore reduces the risk in imaging and costs in terms of finances and time associated with repainting imaging. The modern society is highly health conscious and the risks that come with functional approaches and the invasive mechanism that they employ make them undesirable. Moreover, there is increase in the need for multiple brain testing due to an unexplained increase in the number of mental and neurological cases. Cancer is fast becoming a threat and one would rather implement a system that does not pose any risk of cancer if there is an alternative. Put plainly, MEG would be the method of choice against any functional approach in consideration of the mechanism employed and risk posed. The fact that MEG affords high levels of clarity without being invasive gives it an advantage over the most commonly employed functional approach, EMG which has the con of being invasive. It is worth noting that the levels of clarity that the two approaches attain are comparable. Disadvantages MEG despite all the pros associated with its use has a number disadvantages that may make its use undesirable. Just like the advantages, the cons are resultant from the nature of mechanisms that MEG employs and are therefore internal to MEG as an approach to neuroimaging. These cons may affect the effectiveness of the approach and even increase the associated costs which may make it undesirable. A key drawback in use of MEG stems from the fact that the signals that depict the state of the brain are small and are in a magnitude order that is smaller than typical signal in a clinical environment. It is highly probable that the normal clinic environment may obscure the signals thus most MEG systems employ a shielding to deal with the interference. This is an additional cost that comes on top of installation costs. The cost of shielding and installation makes MEG one of the costly approach to imaging. Anyone who has ever been involved with a medical case that involved the brain will always remember the ordeal due to its nature and cost. The cost of neurological care is high and the employment of costly approaches definitely has a bearing on this cost. In addition, the fact that there is risk of interference by outside forces calls for proper assessment of the environment and continued assessment to ensure accuracy of findings by monitoring interference. Such costs are undesirable in the modern context of healthcare where cost of provision is high due to the high costs of operations. The brain being the centre of the nervous system engages in nearly all kinds of activities. Being a living organ, the brain metabolism is a variable that must be considered in any approach that seeks to determine the state that a brain is in. No full analysis or imaging of the brain can be done without considering its metabolic activity for it has a bearing on the state that brain is in. MEG employs a system that ensures direct measures of the brain activity and disregards any metabolic activity. This reduces the robustness of information that can be obtained by employment of this approach. Diagnosis of any clinical case and ones that involve the physiology of organs often take on an approach where direct measures and rate of metabolism are all determined and analysed (Barkovich, 2005). This is not the case in the implementation of MEG. MEG is more technical than functional approaches, there is therefore need for neuroscientists and technicians to master the internal workings of the machine that provide them with MEG functionalities. In addition to the cost that maintenance of the system has, it puts pressure on the technicians to learn more on the system and this could temporarily infringe on their performance as professionals. This also puts the assessment and imaging at risk of wrong results due to errors arising from hardware or technological failure. In its common application, MEG is used in association with other functional approaches. This is because of its failure to put into consideration the metabolic aspect on physiological assessment. Direct readings are a result of underlying metabolic activities and an understanding of both leads to development of robust analysis. When implemented with other functional approaches, MEG is employed as a secondary approach that brushes on findings from the functional approaches. Despite all its advantages, MEG cannot be used as a standalone approach to neuroimaging where a complete analysis of a condition is required. This is a disadvantage that reduces its effectiveness in application to medical conditions where there is no need for direct readings. Conclusion MEG has clear advantages and disadvantages. Its advantages provide it with high levels of adaptability, accuracy, precision and reduction of risk. All these are important if it is considered that any blunder in analysing the brain could lead to loss of life. The sensitiveness of the brain calls for approaches that are less risky and accurate. On the contrary, the disadvantages which include high cost of implementation; the fact that it cannot be implemented alone and its disregarding brain metabolism have a direct bearing on its advantages. The advantages are realisable but they have to be achieved at a cost which may be high for the ordinary person though a full analysis must often involve functional approaches. Despite this clear reduction in the impact of the advantages, the inclusion of functional approaches results in a robust analysis and a more serious approach to provision of healthcare services which is worth far much more than the cost involved. How to cite MEG: A comparison with Other Functional Neuroimaging Techniques, Papers

Polymer Concrete free essay sample

The greater proportion of concrete is aggregate which is bulky and relatively cheaper than the cement. As much of the constituents of concrete come from stone, it is often thought that concrete has the same qualities and will last forever. Concrete has been called artificial stone, cast stone, reconstructed stone and reconstituted stone. However, concrete must be thought of as a distinct material to stone. It has its own characteristics in terms of durability, weathering and repair. Concrete is a relatively durable and robust building material, but it can be severely weakened by poor manufacture or a very aggressive environment. A number of historic concrete structures exhibit problems that are related to their date of origin. It is referred that the concrete is porous. The porosity is due to air-voids, water voids or due to the inherent porosity of gel structure itself. On account of the porosity, the strength of concrete is naturally reduced. We will write a custom essay sample on Polymer Concrete or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page It is conceived by many research workers that reduction of porosity results in increase of strength of concrete. Therefore, process like vibration, pressure application spinning etc. , have been practiced mainly to reduce porosity. All these methods have been found to be helpful to a great extent, but none of these methods could really help to reduce the water voids and the inherent porosity of gel which is estimated to be about 28%. The impregnation of monomer and subsequent polymerization is the latest technique adopted to reduce the inherent porosity of the concrete to improve the strength and other properties of concrete. These problems can be solved by application of polymer in concrete construction. A polymer is a large molecule containing hundreds or thousands of atoms formed by combining one, two or occasionally more kinds of small molecule (monomers) into chain r network structures. The main polymer material used in concrete construction are polymer modified concrete and polymer concrete. Polymer modified concrete may be divided into two classes: polymer impregnated concrete and polymer cement concrete. The first is produced by impregnation of pre-cast hardened Portland cement concrete with a monomer t hat is subsequently converted to solid polymer. To produce the second, part of the cement binder of the concrete mix is replaced by polymer (often in latex form). Both have higher strength, lower water permeability, better resistance to chemicals, and greater freeze-thaw stability than conventional concrete. Polymer concrete (PC), or resin concrete, consists of a polymer binder which may be a thermoplastic but more frequently is a thermosetting polymer, and a mineral filler such as aggregate, gravel and crushed stone. PC has higher strength, greater resistance to chemicals and corrosive agents, lower water absorption and higher freeze-thaw stability than conventional Portland cement concrete. The pioneering work for the development of polymer concrete was taken up by United States Bureau of Reclamation (USBR). The initial exploratory works carried out at the Brookhaven National Laboratory (BNL) in cooperation with USBR and US in Atomic Energy Commission (AEC) revealed great improvement in compressive strength, permeability, impact resistance and abrasion resistance. The development of concrete-polymer composite material is directed at producing a new material by combining the ancient technology of cement concrete with the modern technology of polymer chemistry. 2. Types of Polymer Concrete Four types of polymer concrete materials are being developed presently. They are: a) Polymer Concrete (PC) b) Polymer Cement Concrete (PCC) c) Polymer impregnated Concrete (PIC) d) Partially Impregnated and surface coated polymer concrete The composites using polymer can be: polymer concrete (PC), when the binder is a polymer that replaces the cement paste, polymer modified concrete (PMC/ PCC), when the polymer is used near cement, polymer impregnated concrete (PIC), when the cement concrete is treated by soaking and polymerization. These composites have some advantages compared to ordinary cement concrete such as,rapid hardening, high mechanical strengths, chemical resistance, etc. Among the disadvantages is their high cost. The utilization domain of polymer concrete is continuously diversifying: PMC is widely used for floor and bridge overlays; acrylic latex has been used to produce mortars which can be sprayed on architectural finish ; PIC was first widely used in bridge decks, pipes and conduits for aggressive fluids, floor tiles, building cladding, hazardous waste containment, post-tensioned beams and slabs, and stay-in place formwork. Polymer concrete is similar to ordinary cement concrete because it contains fine and coarse aggregates, but the hydraulic binder is totally substituted with a polymer material. The aggregates are bounded together by the polymer matrix. Polymer concrete contains no cement or water. The performances of polymeric concrete depend on the polymer properties, type of filler and aggregates, reinforcing fiber type, curing temperature, components dosage, etc. Polymer binder can be a thermoplastic, but more frequently a thermosetting polymer. The polymers most frequently used are based on four types of monomers or pre polymer system: methyl methacrylate, polyester prepolymerstyrene, epoxyde prepolymer hardener and furfuryl alcohol . The aggregates used in dry state can be silicates, quartz, crushed stone, gravel, limestone, calcareous, granite, clay, etc. In the composition can be used also the filler. Different types of fine materials can be used such as: fly ash, silica fume, phosphogyps, cinder, etc. Filler, especially fly ash, can improve the properties of polymer concrete . 3. History †¢ PC was used as early as 1958 in the USA to produce building cladding. Both PC and PCC have been in commercial use since the 1950s †¢ PIC was developed and has been in use since the 1970s †¢ Polymer concrete products have been used for decades in engineering construction like machine foundations, in the building industry for facade products and sanitary parts, in electrical engineering for isolation devices and especial ly in the chemical industry for all types of ducts due to its favourable properties, especially its corrosion resistance as well as its strength and elasticity †¢ The development of polymer concrete products, mostly pipe, dates back to the early 1960`s. The objective was to achieve a substantial increase in resistance to chemical attack †¢ With the development of trenchless technologies (micro-tunneling and pipe jacking) in 1970`s, polymer concrete pipes became popular in sewer systems. As such over the past years, the process of production and manufacturing of polymer concrete products like pipes, manholes and structures have been fundamentally improved †¢ Today it is used for cultured marble for counter tops, lavatories, as repair material, overlays for bridge and floors in sport arenas and stadiums, laboratories, hospitals, factories; also precast PC was used for drains, underground boxes, manholes, acid tanks and cells, tunnel lining, shells, floor tiles, architectural mouldings and machine tools and bases 4. Significance †¢ Depending on the materials employed, PC can develop compressive strengths of the order of 140 MPa within hours or even minutes and is therefore suitable for emergency concreting jobs in mines, tunnels, and highways †¢ PCC possess excellent bonding ability to old concrete, and high durability to aggressive solutions; it has therefore been used mainly for overlays in industrial floors, and for rehabilitation of deteriorated bridge decks. In the case of PIC, by effectively sealing the micro-cracks and capillary pores, it is possible to produce a virtually impermeable product which gives an ultimate strength of the same order as that of PC. PIC has been used for the production of high-strength pre-cast products and for improving the durability of bridge deck surfaces †¢ PCC possess excellent bonding ability to old concrete, and high durability to aggressive solutions; it has therefore been used mainly for overlays in industrial floors, and for rehabilitatio n of deteriorated bridge decks. In the case of PIC, by effectively sealing the micro-cracks and capillary pores, it is possible to produce a virtually impermeable product which gives an ultimate strength of the same order as that of PC. PIC has been used for the production of high-strength pre-cast products and for improving the durability of bridge deck surfaces †¢ Polymer concrete (PC) is a mixture of aggregates with a polymer as the sole binder. To minimize the amount of the expensive binder, it is very important to achieve the maximum possible dry packed density of the aggregate. . Polymer Concrete (PC) Polymer concrete is an aggregate bound with a polymer binder instead of Portland Cement as in conventional concrete. The main technique in producing PC is to minimize void volume in the aggregate mass so as to reduce the quantity of polymer needed for binding the aggregates. This is achieved by properly grading and mixing the aggregates to attain the maximum density and mini mum void volume. The graded aggregates are prepacked and vibrated in a mould. Monomer is then diffused up through the aggregates and polymerization is initiated by radiation or chemical means. A silane coupling agent is added to the monomer to improve the bond strength between the polymer and the aggregate. In case polyester resins are used no polymerization is required. An important reason for the development of this material is the advantage it offers over conventional concrete where the alkaline Portland cement on curing, forms internal voids. Water can be entrapped in these voids which on freezing can readily cracks the concrete. Also the alkaline Portland cement is easily attacked by chemically aggressive materials which results in rapid deterioration, whereas polymers can be made compact with minimum voids and are hydrophobic and resistant to chemical attack. The strength obtained with PC can be as high as 140 MPa with a short curing period. However, such polymer concretes tend to be brittle and it is reported that dispersion of fiber reinforcement would improve the toughness and tensile strength of the material. The use of fibrous polyester concrete (FPC) in the compressive region of reinforced concrete beams provides a high strength, ductile concrete at reasonable cost. Also polyester concretes are visco-elastic in nature and will fail under sustained compressive loading at stress levels greater than 50 per cent of the ultimate strength. Therefore polyester concrete should be considered for structures with a high ratio of live load to dead load and for composite structures in which the polymer concrete may relax during long-term loading. Experiments conducted on FPC composite beams have indicated that they are performance effective when compared to reinforced concrete beam of equal steel reinforcement percentage. Such beams utilize steel in the region of high tensile stress, fibrous polyester concrete (FPC) with its favourable compressive behavior, in the regions of high compressive stress and Portland cement concrete in the regions of relatively low flexural stress. Properties of Polymer Concrete: †¢ Due to good chemical resistance and high initial strength and modulus of elasticity, industrial use of PC has been mainly in overlays and repair jobs. Thermal and creep characteristics of the material are usually not favorable for structural applications of PC. †¢ Polyester concretes are visco-elastic and will fail under a sustained compressive loading at stress levels greater than 50 percent of the ultimate strength. Sustained loadings at a stress level of 25 percent did not reduce ultimate strength capacity for a loading period of 1000 hr. 6. Polymer Cement Concrete (PCC) Polymer cement concrete is made by mixing cement, aggregates, water and monomer, such plastic mixture is cast in moulds. Cured, dried and polymerized. The monomers that are used in PCC are: a) Polyster-styrene. b) Epoxy-styrene c) Furans d) Vinylidene Chloride However, the results obtained by the production of PCC in this way have been disappointing and have shown relatively modest improvement of strength and durability. In many cases materials poorer than ordinary concrete are obtained. This behavior is explained by the fact that organic materials (monomers) are incompatible with aqueous systems and sometimes interfere with the alkaline cement hydration process. Recently Russian authors have reported the production of a superior Polymer cement concrete by the incorporation of furfural alcohol and aniline hydrochloride in the wet mix. This material is claimed to be specially dense and non-shrinking and to have high corrosion resistance, low permeability and high resistance to vibrations and axial extension. Washington State University in cooperation with Bureau of Reclamation tested the incorporation of several monomers into Wet Concrete for preparing PCC for fabrication of distillation units for water desalination plants. However, it is reported that only epoxy resin produced a concrete that showed some superior characteristics over ordinary concrete. †¢ The materials and the production technology for concrete in PCC are the same as those used in normal Portland Cement concrete except that latex, which is a colloidal suspension of polymer in water, is used as an admixture. †¢ Earlier latexes were based on polyvinyl acetate or polyvinylidene chloride, but these are seldom used now because of the risk of corrosion of steel in concrete in the latter case, and low wet strengths in the former. Elasto-meric or rubberlike polymers based on styrenebutadiene and polyacrylate copolymers are more commonly used now. Latex: †¢ A latex generally contains about 50 % by weight of spherical and very small (0. 01 to 1 m in diameter) polymer articles held in suspension in water by surface-active agents. †¢ The presence of surface-active agents in the latex tends to incorporate large amounts of entrai ned air in concrete; therefore, air detraining agents are usually added to commercial latexes. 10 to 25 percent polymer (solid basis) by weight of cement is used in typical PCC formulations †¢ The addition of latex provides a large quantity of the needed mixing water in concrete. †¢ The application of PCC is limited to overlays where durability to severe environmental conditions is of primary concern. †¢ PCC is made with as low an addition of extra mixing water as possible; the spherical polymer molecules and the entrained air associated with the latex usually provide excellent workability. Concrete Mix and Curing: †¢ Typically, water-cement ratios are in the range0. 40 to 0. 5, and cement contents are on the order of 390 to 420 kg/m3. †¢ The hardening of a latex takes place by drying or loss of water. †¢ Dry curing is mandatory for PCC; the material cured in air is believed to form a continuous and coherent polymer film which coats the cement hydration products, aggregate particles, and even the capillary pores. Properties: †¢ The most impressive characteristics of PCC are its ability to bond strongly with old concrete, and to resist the entry of water and aggressive solutions. †¢ It is believed that the polymer film lining the capillary pores and micro-cracks does an excellent job in impeding the fluid flow in PCC. These characteristics have made the PCC a popular material for rehabilitation of deteriorated floors, pavements, and bridge decks. 7. Polymer Impregnated Concrete (PIC) Polymer impregnated concrete is one of the widely used polymer composite. It is nothing but a pre-cast conventional concrete, cured and dried in oven, or by dielectric heating from which the air in the open cell is removed by vacuum. Then a low viscosity monomer is diffused through the open cell and polymerized by using radiation, application of heat or by chemical initiation. Mainly the following types of monomer are used: a) Methylmethacryl ate (MMA) ) Styrene c) Acrylonitrile d) T-butyl styrene e) Other thermoplastic monomers The amount of monomer that can be loaded into a concrete specimen is limited by the amount of water and air that has occupied the total void space. It is necessary to know the concentration of water and air void in the system to determine the rate of monomer penetration. However, the main research effort has been towards obtaining a maximum monomer loading in concrete by the removal of water and air from the concrete by vacuum or thermal drying, the latter being more practicable for water removal because of its rapidity. Another parameter to consider is evacuation of the specimen prior to soaking in monomer. This eliminates the entrapment of air towards the centre of the specimen during soaking which might otherwise prevent total or maximum monomer loading. The application of pressure is another technique to reduce monomer loading time. 8. Partially Impregnated (or Coated in Depth CID) and Surface Coated (SC) Concrete Partial impregnation may be sufficient in situations where the major requirement is surface resistance against chemical and mechanical attack in addition to strength increase. Even with only partial impregnation, significant increase in the strength of original concrete has been obtained. The partially impregnated concrete could be produced by initially soaking the dried specimens in liquid monomer like methyl methacrylate, then sealing them by keeping them under hot water at 70 C to prevent or minimize loss due to evaporation. The polymerization can be done by using thermal catalytic method in which three per cent by weight of benzoyl peroxide is added to the monomer as a catalyst. It is seen that the depth of monomer penetration is dependent upon following: a) Pore structure of hardened and dried concrete ) The duration of soaking, and c) The viscosity of the monomer The potential application of polymer impregnated concrete surface treatment (surface coated concrete, SC) is in improving the durability of concrete bridge decks. Bridge deck deterioration is a serious problem everywhere, particularly due to an abrasive wear, freeze-thaw deterioration, spall ing and corrosion of reinforcement. Excellent penetration has been achieved by ponding the monomer on the concrete surface. Due care should be taken to prevent evaporation of monomer when ponded on concrete surface. A 5 cms thick slab, on being soaked by MMA for 25 hours produced a polymer surface coated depth of 2. 5 cms. Significant increases in the tensile and compressive strengths, modulus of elasticity and resistance to acid attack have been achieved. The application of monomer for field application like in bridge decks poses more problems than laboratory application. A typical surface treatment in the field can be done in the following manner. a) The surface is dried for several days with electrical heating blanket. b) Remove the heating blanket and cover the slab with 0. 4 cum oven-dried light-weight aggregate per 100 sqm. c) Apply initially 2,000 to 3,000 ml of the monomer system per square meter. d) Cover the surface with polyethylene to retard evaporation. e) Shade the surface to prevent temperature increase which might initiate polymerization prematurely, that may reduce penetration into the concrete. f) Add periodically additional monomer to keep the aggregate moist for minimum soak time of 8 hours. g) Apply heat to polymerize the monometer: Heating blanket, steam or hot water can be used for this purpose. Some of the promising monomer systems for this purpose are: ) Methylmethacrystalate (MMA), 1% Benzoyl peroxide (BP), 10% Trimethylopropane thimethacrylate (TMPTMA). b) Isodecyl methacrystalate (IDMA), 1% BP, 10% TMPTMA c) Isobutylmethacrystalate (IBMA), 1% BP, 10% TMPTMA BP acts as a catalyst and TMPTMA is a cross linking agent which helps in polymerization at low temperature of 52%C. 9. Properties of Polymer Impregnated Concrete Since polymer impregnated concrete (PIC) is one of the most important category of polymer concrete, the properties of PIC are discussed below. Stress – Strain Relationship The stress strain curve for MMA –impregnated concrete tested to failure is shown in fig. elow.. PIC has a nearly linear stress strain relationship to failure. There is very little departure from linearity upto 90% of ultimate strength and there is no abrupt change at the proportional limit. The stress strain curves for Styrene TMTMPTMA impregnated concrete also show the same characteristics as for MMA impregnated concrete. The modulus of elasticity increased from 27 GPa for un-impregnated specimen to 49 GPa for MMA impregnated specimens. [pic] Compressive Strength The effect of polymer loading on the compressive strength in PIC is given in the following figure. Using methylemethacrystalate as monomer and with a polymer loading of 6. 4%, strength of the order of 144 MPa have been obtained using radiation technique of polymerization. (The control specimen had compressive strength of 38 MPa). The compressive strength obtained with thermal catalytic process was 130 MPa. [pic] [pic] Styrene impregnated specimens exhibit similar trends, except that the strength levels were somewhat lower. The polymerization by radiation method produced a concrete of higher strength than the produced by thermal catalytic method. Perlite concrete impregnated with MMA and polyester styrene have also shown considerable increases in compressive strengths. It is found the higher strengths are obtained with MMA impregnated sample than with polyester styrene. The average compressive strength for a 1:8 non-air entrained perlite concrete samples, impregnated with MMA was 56 MPa for polymer loading of 63% compared to control specimen of compressive strength 1. 2 MPa. Tensile Strength The increase in tensile strength in the case of PIC has been observed to be as high as 3. times that of the control specimen for polymer loading of 6. 4% MMA i. e. impregnated concrete have shown tensile strength of the order of 11. 6 MPa compared to the strength of control specimen of 3 MPa using radiation process of polymerization. Thermal catalytically initiated polymerization, produced concrete with tensile strength 3. 6 times that of the control specimen and 7. 3% less than that of radiation produced concrete. Polymer Concrete : Poly ester resin concrete with binder continent varying from 20 to 25% have shown tensile strengths in the range of 9 to 10 MPa at 7 days. Polymer Cement Concrete: Polymer cement concrete using latex has given tensile strength of 5. 8 MPa with a latex / cement ratio of 0. 25; compared to the control specimen of 4. 4 MPa strength. The increase in tensile strength is very modest. Flexural Strength Polymer impregnated concrete with polymer loading of 5. 6% MMA and polymerized by radiation have shown flexural strength 3. 6 times more than that of the control specimen, i. e. the flexural strength was increased to 18. 8 MPa from 5. 2 MPa. Polymer Concrete (PC) Polymer resin concrete has been reported to give flexural strength of the order of 15 MPa at 7 days. Creep Compressive Creep deformation of MMA impregnated concrete and styrene-impregnated concrete has been observed to be in direction opposite to that of the applied road i. e, Negative Creep. After the typical initial movement during load application, these concretes expand under sustained compression. The reason for this negative creep in PIC is not very clear though it may be possible that it is due to residual stresses generated in the concrete after polymerization of monomers. The increased volume may also be due to phase changes induced by pressure. This behaviour has been noticed at a relatively loiw loading of 5. MPa. Otherwise creep deformation of PIC concrete is generally one-tenth of conventional concrete, when compared on a basis of deformation per unit load. Creep deformation generally stabilizes after two to three months. Shrinking due to Polymerisation Shrinkage occurs through two stages of impregnation treatment i. e. , through initial drying and through polymerisatio n. The shrinkage through polymerisation is peculiar to PIC and could be several times greater than the normal drying shrinkage. It has been seen that for the same base material, different monomer systems cause different amounts of shrinkage. It is expected that the shrinkage due to polymerisation will be less for a base that has higher modulus of elasticity. Durability The saturation of the hydrated cement with corrosion resistant polymer probably acts as a protective coating and results in excellent improvement in durability. a) Frees Thaw Resistance: Polymer impregnated concrete has shown excellent resistance to freeze-thaw MMA impregnated and radiation polymerized specimens have withstood 8110 cyclens of freeze-thaw compared to 740 cycles in case of unimpregnated concrete. Even partially impregnated concrete withstood 2310 cycles. ) Resistance to Sulphate Attack: Keeping a failure criteria of 0. 5% expansion, it has been observed that there is atleast 200 percent improvement in the resistance of polymer impregnated concrete and 89% improvement in the case of partially impregnated concrete over the conventional concrete. c) Acid Resistance: The acid resistance of PIC has been observed to improve by 1200 percent when ex posed to 15% HCI for 1395 days. Water Absorption A maximum reduction of 95 percent in water absorption has been observed with concrete containing 5. 9 percent polymer loading. Co-efficient of Thermal Expansion: Polymer impregnated concrete has higher co-efficient of thermal expansion compared to conventional concrete. Compared to the unimpregnated concrete having a value of 4. 02 X 10-6, a 5. 5% MMA, radiation polymerized concrete has a co-efficient of thermal expansion of 5. 63 X 10-6, and styrene impregnated specimens have shown a value of 5. 10 X 10-6. Resistance to Abrasion Polymer impregnated concrete has shown appreciable improvement in resistance to abrasion. A 5. 5% MMA impregnated concrete has been found to be 50 to 80 per cent more resistance to abrasion than the control specimen. Even surface impregnated concrete slabs have shown an improvement of 20 to 50%. Wear and Skid Resistance. Though there may be apprehension that polymer filled voids in polymer concrete might produce a slippery surface, on actual wear track test, it was found that the treated surfaces show excellent skid resistance compared to the unimpregnated surfaces. The wear after 50,000 simlated vehicular passes has been less than 0. 025cm. Fracture of Polymer impregnated Concrete Polymer impregnation of concrete changes its microstructure radically resulting in a change in the cracking behaviour of the impregnated concrete under load. Impregnation improves the strength of the mortar matrix and also the strength of the paste-aggregate interface by elimination of microcracks. Polymer probably enters the aggregates also and forms a network of polymer fibres across the interface, thus strengthening it. Radiographic studies have shown that micro cracking starts first around 70 to 80% of the ultimate load, very often in the mortar phase. When an advancing crack reaches an aggregate, it does not follow the aggregate boundary as in ordinary concrete, but usually propagates through the aggregate. This indicates that the paste aggregate interface bond is significantly improved by polymer impregnation. It has been observed that PIC indicates nearly linear behaviour to failure, which is typical of brittle material. The brittle nature of PIC presents a severe design limitation. It would be ideal to produce a material with the slow failure mode of normal concrete while retaining the high strength and modulus of elasticity of PIC. One method to achieve this ideal is to adjust the past aggregate bond so that the failure mode is through the interface like in ordinary concrete. In principle, this can be achieved by using a very strong and tough aggregate, so that the advancing crack is diverted round to the paste-aggregate interface. The fracture mode of PIC can also be altered by incorporating a small quantity (1% by volume) of fibres in the matrix. The fibres do not affect the modulus of elasticity of concrete due to their low concentration, but serve to inhibit crack propagation through the mortar by acting as crack arrestors. 10. Sequence of Operations Drying and evacuation: The time and temperature needed for removal of free water from the capillary pores of moist-cured products depend on the thickness of the elements. At the drying temperatures ordinarily used (i. e. , 105 C), it may require 3 to 7 days before free water has been completely removed from a 150- by 300-mm concrete cylinder. Temperatures on the order of 150 C can accelerate the drying process so that it is complete in 1 to 2 days. Soaking the dried concrete in a monomer: The in situ penetration of concrete in the field may be achieved by surface ponding, but precast elements are directly immersed in the monomercatalyst mixture. Commercial monomers contain inhibitors that prevent premature polymerization during storage; the catalyst serves to overcome the effect of the inhibitor. Sealing the monomer: To prevent loss of monomer by evaporation during handling and polymerization, the impregnated elements must be effectively sealed in steel containers or several layers of aluminum foil; In the rehabilitation of bridge decks this has been achieved by covering the surface with sand. Polymerizing the monomer: Thermal catalytical polymerization is the preferred technique. The time for complete polymerization of the monomer in the sealed elements exposed to steam, hot water or air, or infrared heat at 70 to C may vary from a few to several hours. In the case of a MMA-benzoyl peroxide mixture, no differences in strength were found between specimens polymerized at C with hot air for 16 hr or with hot water for 4 hr. 11. Application of Polymer Impregnated Concrete Keeping in view the numerous beneficial properties of the PIC, it is found useful in a large number of applications, some of which have been listed and discussed below: a) Pre-fabricated structural elements. ) Pre-stressed Concrete c) Marine works d) Desalination Plants e) Nuclear Power plants f) Sewage works-pipe and disposal works. g) Ferro cement products h) For water proofing of structures i) Industrial applications a) Pre-fabricated Structural Elements: For solving the tremendous problem of Urban Housing shortage, maintaining quality, economy and speed, builders had to fall back on pre-fabr icated techniques of construction. At present due to the low strength of conventional concrete, the pre-fabricated sections are large and heavy, resulting in costly handling and erection. These reasons have prevented wide adoption of pre-fabrication in many countries. At present, the technique of polymer impregnation is ideally suited for pre cast concrete, it will find unquestionable use in industrialization of building components. Owning to higher strength, much thinner and lighter sections could be used which enables easy handling and erection. They can be even used in high rise building without much difficulties. b) Pre-stressed Concrete: Further development in pre-stressed concrete is hindered by the inability to produce high strength concrete, compactable with the high tensile steel available for pre-stressing. Since PIC provides a high compressive strength of the order of 100 to 140 MPa, it will be possible to use it for larger spans and for heavier loads. Low creep properties of PIC will also make it a good material for pre-stressed concrete. c) Marine Works: Aggressive nature of sea water, abrasive and leaching action of waves and inherent porosity, impair the durability of conventional concrete in marine works. PIC possessing high surface hardness, very low permeability and greatly increased resistance to chemical attack, is a suitable material for marine works. ) Desalination Plants: Desalination of sea water is being resorted to augment the shortage of surface and ground water in many countries. The material used in construction of flash distillation vessels in such works has to withstand the corrosive effects of disilted water, brine and vapour at temperature up to 1430 C. Carbon steel vessels which are currently in use are comparatively costly and deteriorate after prolonged use. Pr eliminary economic evaluation has indicated a savings in construction cost over that of conventional concrete by the use of PIC. ) Nuclear Power Plants: To cope up with the growing power requirements for industrial purposes, many countries are resorting to nuclear power generation. The Nuclear contained vessel (Pressure vessel) is a major element, which is required to withstand high temperatures and provide shield against radiations. Another attendant problem of nuclear power generation is the containment of spent fuel rods which are radioactive over long period of time to avoid radiation hazards. At present heavy weight concrete is being used for this purpose, which is not very effective. PIC having high impermeability coupled with high strength and marked durability provides an answer to these problems. f) Sewage Disposal Works: It is common experience that concrete sewer pipes deteriorate due to the attack of effluents and when buried in sulphate infested soils. Further in the sewage treatment plant, concrete structures are subjected to severe attack from corrosive gases particularly in sludge digestion tanks. Polymer-impregnated concrete due to its high sulphate and acid resistance, will prove to be a suitable material in these situations. ) Impregnation of Ferro-cement products: The ferro-cement techniques of construction is being extensively used in the manufacture of boats, fishing trawlers, domestic water tanks, grain storage tanks, man hole cover, etc. , Ferro cement products are generally this (1 to 4 cms) and as such are liable to corrode. Application of polymer impregnation techniques should improve the functional efficiency of ferro-cement products. h) Wat er Proofing of Structures: Seepage and leakage of water through roof and bathroom slabs, it a nagging problem and has not been fully over come by the use of conventional water proofing methods. The use of polymer impregnated mortar should solve this problem. i) Industrial Applications: Concrete has been used for floor in tanneries, Chemical Factories, dairy farms and in similar situations for withstanding the chemical attack, but performance has not been very satisfactory. The newly developed PIC will provide a permanent solution for durable flooring in such situations. 12. Case Studies: Two case studies are presented as follows: 1. Properties of Fiber Reinforced Polymer Concrete studied by Marinela Barbuta and Maria Harja 2. Polymer Concrete for Structural Restoration and Corrosion Protection of Concrete Support Columns. I. Properties of Fiber Reinforced Polymer Concrete studied by Marinela Barbuta and Maria Harja The experimental results of studies regarding polymer concrete with cellulose fibers are presented. The compositions used in the present study derive from a previous one which investigated a large number of compositions using different dosages of resin and filler. The mechanical characteristics such as: compressive strength, flexural strength and split tensile strength were investigated on fiber reinforced polymer concrete made with different dosages of resin and filler, the fiber dosage being constant for all mixtures. Materials The experimental researches on polymer concrete were made by using the following materials: polymer, fly ash as filler, crushed aggregates and fiber type ARBOCEL. The polymer was type epoxy resin, called ROPOXID, made in Romania by POLICOLOR Bucharest . The hardener was type ROMANID 407, also made by POLICOLOR Bucharest. The fly ash (FA) from the power plant CET Holboca, Jassy, was added to the fine aggregates. The fly ash is an inorganic waste produced by burning pulverized coal in power stations. Fly ash consists of many small, glass-like particles ranging in size from 0. 01 to 100 ? m. Chemically FA contains oxides, hydroxides, carbonates, silicates, and sulphates of calcium, iron and aluminum. The content in carbon is given from loss ignition. FA is a heterogeneous mixture of amorphous and crystalline phases and is generally considered to be a ferroaluminosilicate element. The mineralogical, physical and chemical properties of FA depend on the nature and composition of the coal, conditions of combustion, type of emission control devices, storage and evacuation methods. Storage methods may affect weathering rates, especially under humid conditions where soluble constituents may be leached. The principal characteristics of FA are: colour gray to black, function of carbon unburned, particles sizes between 0. 01 to 100 ? m; the shape of particles is spherical, specific surface is between 4,800. . . 5,200, the density is between 2,400 and 2,550 kg/m3 [ The aggregates were used in two sorts: 0. . . 4 mm and 4. . . 8 mm, with continuous granulosity, obtained from crushed river gravel by S. C. EMBERON SRL Jassy. The ARBOCEL fibers are natural cellulose fibers, produced by J. Rettenmaier S? ohne GMBH. ARBOCEL is produced from cellulose in various qualities (fiber lengths, thicknesses, purities, etc. The properties of ARBOCEL cellulose fibers are: mean fiber length of 10 ? m, completely safe, insoluble in water and organic solvents, resistant to dilute acids and bases. The fiber was used in proportion of 3% from the mass of resin plus the hardener. Experimental Samples For the study of polymer concrete properties nine compositions (BPFF) were prepared in the experimental progr am (Table 1). [pic] The polymer concrete with different compositions as is given in Table 1, was prepared by mixing firstly the resin with hardener, then after complete homogenization the fibers were introduced in the mixture as shown in fig below [pic] Fig 1. Cellulose fiber mixing with resin. The fly ash was added to the mix of aggregates and the resin and aggregates were mixed by the mechanical mixer. After complete mixing, the polymer concrete was poured in formworks. For each composition the density was determined. The following mechanical characteristics were experimentally tested: compressive strength on cube sample of 70. 7 mm sizes, flexural strength and split tensile strength on prismatic samples of sizes 210? 70? 70 mm, according to standard prescriptions. [pic] Fig. 2. – Samples of polymer concrete with fibers. Results and Discussions According to EN 12390/2001 the mechanical characteristics of polymer concrete with cellulose fiber, experimentally determined namely: compressivestrength (fc), flexural strength (fti) and split tensile strength (ftd) are given in Table below . [pic] From the experimental results the following observations can be made: a) The values of compressive strengths for polymer concrete with fibers (Fig. 3) vary between 62. 62 MPa (for BPFF7) and 46. 41 MPa (for BPFF2). Fig. 3. – Variation of compressive strength for polymer concrete with fiber. [pic] Fig. 3. – Variation of compressive strength for polymer concrete with fiber. ) With the increasing of resin and fly ash dosage the compressive strengths increase (Figs. 4 and 5). [pic] Compressive strength, MPa Fig. 4. – Variation of compressive strength for polymer concrete with fiber vs. the resin content, for 6. 4% FA. [pic] Fig. 5. – Variation of compressive strength for polymer concrete with fiber vs. the FA conte nt, for 12. 4% resin. d) The values of flexure strengths for polymer concrete with fibers (Fig. 6)vary between 17. 57 MPa (for BPFF9) and 13. 55 MPa (for BPFF8), so, the decrease of resin dosage results in the increase of flexure strength. pic] Fig. 6. – Variation of flexural strength for polymer concrete with fiber. [pic] [pic] Fig. 7. – Variation of split tensile strength for polymer concrete with fiber: a – vs. the resin content; b – vs. the sample number. d) The values of split tensile strengths for polymer concrete with fibers (Fig. 7) vary between 6. 94 MPa (for BPFF9) and 4. 29 N/mm2 (for BFF7); the increase of resin dosage results in the increase of split tensile strength. The experimental researches lead to the following observations: a) For the maximum epoxy resin dosage (16. %) compressive strength is reduced near minimum value, the flexure strength is medium, but the split tensile strength has high value. b) For the minimum epoxy resin dosage (12. 4%) compressive strength is reduced under the medium value, the flexure strength is also reduced, and the split tensile strength has value over the medium. c) For the maximum fly ash dosage (12. 8%) compressive strength and flexurestrength are medium, but the split tensile strength is near the highest value. d) For the minimum fly ash dosage (6. 4%) compressive strength and flexure strength are under the medium and the split tensile strength is near medium value. ) For the same dosage of epoxy resin the maximum compressive strength and flexure strength were obtained for maximum fly ash dosage. It results that for increasing the compressive strength and flexure strength at same dosage of resin and fiber, it must be used the maximum dosage of fly ash. f) For the split tensile strength it must be used a medium fly ash dosage; The values of mechanical characteristics of polymer concrete are smaller then those of mechanical characteristics obtained for polymer concrete with silica f ume and polymer concrete with fly ash . The author concluded that The experimental researches concerning the polymer concrete had investigatedthe mechanical characteristics of epoxy polymer concrete prepared with cellulose fibers and fly ash as filler. †¢ When the same dosage of cellulose fibers is used, the content of resin must be increased. Also for obtaining good mechanical properties the filler is used with higher dosages. †¢ The experimental values of mechanical strengths for polymer concrete with cellulose fibers were smaller then that for polymer concrete without fibers. This type of fibers is not a good choice for polymer concrete reinforcement. II. Polymer Concrete for Structural Restoration and Corrosion Protection of Concrete Support Columns by David E. Snider and Heather M. Ramsey of Sauereisen Inc. A large copper mine and refinery in the western United States had a dilemma. Their cell house, which contains over 1,500 cells, each holding more than 20,000 gallons of electrolyte, had experienced severe corrosion and structural degradation of the support columns for the tanks. These columns support the cells in their solvent extraction and electrowinning process. This process entails immersion of a stainless steel cathode or â€Å"starter plate† into the electrolyte. Pure copper is deposited onto the starter plate during this 10-day digestion process. The collected copper is then further refined at a separate location. Over time, highly acidic leakage from the cells had corroded the support columns to the point that their ability to adequately withstand the imposed load was in doubt. Additionally, the refinery desired to upgrade the facility’s ability to withstand seismic activity. The leakage, primarily copper sulfate and 25% sulfuric acid at a pH of 1. 0 or less, corroded not only the concrete but more significantly the reinforcement bar (rebar) encased in the concrete. Corrosion of the rebar resulted in an increase of internal pressure due to expansion of the corrosion products, therefore putting the concrete in high tensile stress. The direct effect of this stress was cracking and spalling of the concrete. Figure 1 shows a typical degradated column requiring restoration. [pic] The original construction of the columns used the rebar spaced 6-inches on center vertically and 18-inches on center horizontally. The refinery’s standard repair procedure was to remove corrosion products from the concrete and steel and then to top them with a polymer-modified portland-cement mortar. This standard repair method requires two (2) to three (3) days per column, and although temporarily affective, did not meet the company’s desire for a long-term solution. They decided upon a new approach using a polymer concrete (PC), which is a bisphenol A based-epoxy. This material is designed for maximum flowability, mechanical properties and chemical resistance. The PC repair system utilizes the polymer concrete for encapsulation, chemical protection, mechanical support and resistance to physical abuse. Figures 2 illustrates the method by which the stainless steel rebar was attached to the columns after surface-preparation. Stainless steel rebar was imbedded into the concrete floor using an epoxy mortar. Channels were saw-cut vertically in the concrete column. These channels provided a recess into which the rebar was bent and then secured into place with the epoxy mortar. Grouting of the rebar with this high strength epoxy mortar also served to provide tensile stress relief. By lowering stress relief, corrosion rates are reduced. [pic] Figure 2. Stainless steel rebar bent and grouted into the channels. To further ensure structural integrity and to upgrade seismic capabilities, the company chose to use fiberglass reinforcement (FRP) strips and wraps nder the PC. The strips were installed vertically on the columns and a fiberglass fabric was wrapped around the columns horizontally. The columns were formed and the polymer concrete was poured into place completely encapsulating the columns, the rebar and the FRP. This method required two (2) days per column. To date, 75 columns have been repaired using this method. Figures 3 and 4 show the forming and pouring of the PC. Figure 5 shows the PC after the form has been removed and the FRP that was applied to the columns. [pic] Figure 3. The forms placed around the column. . [pic] As mentioned earlier, an important property of the PC is the flowability. The test for this property is ASTM C-143 and measures the â€Å"slump† of the polymer concrete. (Figure 6). A slump of 6 inches is considered to be flowable. This particular polymer concrete exhibits a slump of 8-inches, which is very flowable. Figures 6, 7 and 8 illustrate the flowability of the polymer concrete mixture. Table 1 lists some of the other physical properties of the polymer concrete used on this repair that were important considerations. [pic] Property at 7-days Value Property at 7- Days | Value | |Density |135 pounds/cft (2. 2gm/sq. cm) | |Compressive Strength |12,000 psi (84. 4 N/sq mm) | |Flexural Strength |3,000 psi (21. 1 N/ Sq. mm) | |Modulus of Elasticity |1. 08x 10(6)psi 7600 N/Sq mm | |Shrinkage` |0. 9 % | |Tensile Strength |2,400 psi (16. 9 N/Sq. mm) | The PC is roughly three times as strong as a portland cement mix (about 4,000 psi (281 kg / sq. cm. 28. 1 N/sq mm)) and is not chemically affected by the electrolyte. These properties make it an ideal product for the column restoration. As expected, none of the 75 columns repaired to date have exhibited any signs of failure and have required no maintenance since the repair program commenced in early 2007. Coatings will typically have a service life of 8 to 15 years depending upon the exposure and physical abuse. However, in this case, typical service life of coatings was six months. Their service life is also affected and somewhat limited as a result of application thickness. Coatings are generally applied at thicknesses ranging from a few mils up to a few hundred mils. Polymer concretes, however, are applied at a minimum thickness of 1 inch and may be applied as thick as 18 inches. The thickness of barrier coatings determines the overall permeability, which is a measure of water vapor’s ability to pass through a material. If the coating is less than 250 mils, the method used to determine permeability is based on the water-vapor transmission (WVT) test ASTM E-96 or ASTM D-1653. Permeance is calculated from WVT. Permeability is obtained by multiplying permeance by thickness. A permeability of 10-8 (1. 49 x 10- 17 grams/Pa†¢s†¢m) or less is generally considered to provide a good barrier coating. Also due to the thickness, and other considerations, the service life of a polymer concrete is longer and requires far less maintenance. Experience with PCs by this manufacturer has shown no failures after 15 years of service. Laboratory evaluations coupled with field observations indicate the service life of PCs to be typically greater than 25 years. Figure 9 illustrates the completed column, including a protective topcoat for the FRP reinforced concrete. Although not needed for functionality, the topcoat was extended over the PC for aesthetics and coating integrity. [pic] Figure 9. Completed column repair. Many users of polymer concretes will entirely replace portland concrete with a full thickness of the polymer concrete. This is particularly true when extended downtimes are prohibitive. The lengthy cure time for standard portland based ement prior to receiving a protective coating is unacceptable for many facilities. After placement, polymer concretes may be placed into full chemical service after a 24-hour cure. Furthermore, with the strengths achieved with PC, it is usually possible to reduce the overall thickness to about ? of that commonly used with portland concretes. Typical thicknesses for PCs r ange from 1-inch to 4-inches. Polymer concretes may be engineered, formed and placed in the same manner that one would employ with a portland concrete structure. They also are reinforced in the same manner as portland concretes. Polymer concrete thicknesses are typically much less than that of the Portland concrete, therefore smaller diameter rebar is often used. At a thickness of 1 inch, one would use lesser thick rebar instead of a reasonably higher thick rebar commonly found with portland concrete constructions. Due to the ease of installation, the facility’s local preferred contractor was able to perform the work. The author concluded that Polymer concretes, which do not contain portland cement, have demonstrated tenacity as a protective barrier material in this difficult application and many others. This application required corrosion protection from a severely aggressive electrolyte, as well as protection from physical abuse. Other essential requirements were a system affording both ease of use and a quick turnaround time. Polymer concretes are also proving to be cost effective alternatives to using portland cement-based concretes with chemical-resistant topcoats for corrosion protection. The cost of maintenance for polymer concretes per year of service life is significantly less than that of concrete with applied barrier coatings, which may require multiple re-applications over the same number of years of service. Conclusion: 1. The major factor that has been responsible for the extensive use of polymer-based materials in civil engineering is their advantages, viz . increased tensile strength, compressive strength, freeze-thaw durability, and decreased water permeability to a negligible value. 2. Owing to its excellent resistance to chemical attack i. e sulphate attack, acidic attack, saline water, radiation from nuclear substances polymer concrete has great potential over Portland cement for the design of structures in such industries, desalination plants, nuclear plants, underwater structures, overlays in bridge decks. . There are many type of application of repairing material available such as grout, motar, concrete, sprayed concrete and cement based material. Among these, resin based materials are performed much better than the others. 4. The cost of maintenance for polymer concretes per year of service life is significantly less than that of concrete with applied barrier coatings, which m ay require multiple re-applications over the same number of years of service. 5. Extended use of pre stressed elements could be permitted with the reduced permeability possible. 6. The incorporation of dyes with the plastics used for polymerization opens another aesthetic aspect of concern to civil engineers and architects, as does the potential size decrease for greater span/depth ratios. 7. The only barrier to be focussed on is its higher cost in comparison to OPC and further research for economic production of polymer concrete would help to overcome this problem. References 1. â€Å"Properties of Fiber Reinforced Polymner Concrete†, Msrinela Barbuta and Maria Harja, Univerisity Technica, Tomul LIV(LVIII) Fasc,3, 2008, Constructii Architectura. . Muttukumar M. , Mohan D. J. , Polymer Res. 12, (2004) 3. â€Å"Polymer Concrete for Structural Restoration and corrosion protection of Concrete Support Columns† of David E. Snider and Heather M. Samsey of Sauereisen Inc. , 4. â€Å"Polymer concrete and its potential in the Construction industry†, Luke M. Snell,1 H. Aldridge Gillespie, and Robert Y. Nelson, Department of Civil Engineering, West Vi rginia University, Morgantown, West Virginia, and School of Civil Engineering and Environmental Science, University of Oklahoma Norman