Friday, October 18, 2019
Policy memo to the President on Sino-American relationships Essay
Policy memo to the President on Sino-American relationships - Essay Example One of the greatest challenges facing the US is possibility of nuclear attacks from defiant North Korea and similar attacks on US allies such as South Korea and Japan. The United States bilateral partnerships with East Asia nations like Japan aim at defending such nations in case of military confrontation from hostile neighbors (Shambaugh, 2013). Another challenge facing the US in East Asia is the increased integration and cooperation of East Asia countries in trade and formation of regional economic blocs that determine the trade flows in the region (Lin & Roy, 2010). The rise of China as an economic and military power has dwindled the influence of United States in geopolitical issues affecting East Asia. China has the potential to influence East Asia trading activities and determine the capacity of the US to find strategic partners and allies in the region (Shambaugh, 2013). Nationalism, unresolved historical issues and territorial borders is another challenge that limits the abili ty of the US to interfere with East Asia issues (Lin & Roy, 2010). Territorial border tensions have fueled military confrontation and led to high military build-up and spending by some East Asia nations thus limiting their capability to focus on trade and investment spending. In this case, the US must use a careful and diplomatic approach in its comments relating to territorial disputes in order to avoid diplomatic tensions in the region (Shambaugh, 2013).
Gangs and gang behavior - week 5 Essay Example | Topics and Well Written Essays - 250 words - 1
Gangs and gang behavior - week 5 - Essay Example disruptive conduct disorders before entry into school system (Kalb &Loeber, 2003) and, according to Loeber and Farrington (2001), these problems develop later during growth. The later theory is backed by Vaughn and colleagues (2009), who argue that children become more exposed to an array of risks during the elementary period and onward and also argue that children get more vulnerable to bad peer influences outdoor. In other cases, some theories do not highlight other potential causes of this problem of gang involvement, for example, Loeber, Farrington and Petechuk (2003) including Tremblay (2003) discover that concentrated disadvantages obstruct socialization of juveniles. Loeber and Farrington (2001) talk about relevant family variables present at the preschool level, low social resources and a number of family hitches inclusive. On another account, Pogarsky, Lizotte and Thornberry (2003) identified broken families, parental delinquency, poor child management, abuse, grave matrimonial conflicts and inexperienced young motherhood. With regards to the above, it is vivid to see that other theories actually forget to put into account other relevant factors. In another analysis, theories contend for example Kroneman, Loeber and Hipwell (2004) who strongly assimilate societal poverty with behavioral problem and specifically girls, Hipwell (2002) as well as Wei (2005) make a conclusion regarding the same theory highlighting girls become the most affected in disadvantaged neighborhoods. Some factors are common across all the four developmental stages as well as the theories, therefore, this means that a single theory can be developed out of all the theories with respect to the developmental stages of a
Thursday, October 17, 2019
Personal development and ethics Assignment Example | Topics and Well Written Essays - 2500 words
Personal development and ethics - Assignment Example One develops these over time and many factors influence how theyââ¬â¢re crafted. However good and bad or right and wrong are very broad terms and differ from society to society and within different cultures, races and peoples. There are a whole lot of grey areas and overlapping nuances between the rigidity of good and bad or right and wrong. Perhaps the meaning of these terms may even vary depending on our own experiences. For example we have all been taught that taking another personââ¬â¢s life is wrong. When a murderer who is convicted of mass murder is brought to book many of us may think that he deserves the death penalty, yet somewhere in our hearts we may find the compassion to allow him the option of a life sentence that would possibly allow him to repent and do some good. Consider however that the victim is a loved one, would you then feel any compassion for the murderer? Here then is the difference in each oneââ¬â¢s ethics. So, we may define them as a personal code of conduct or those principles by which one makes choices in life regarding what is right or wrong, good or bad. The process of personal development begins long before we even understand the meaning of the term in its entirety. A baby needs love and care and deprived of these the baby may suffer ill effects that can irreparably warp his/her personal development and lead to personality problems in later life. A young childââ¬â¢s personal development begins, in the home and he/she usually has a role model in whose image the child would like to transform him/her. This image changes as one grows and is usually different at different times in oneââ¬â¢s life. A childââ¬â¢s earliest role model is a parent ââ¬â a picture of a young boy comes to mind proudly proclaiming his fatherââ¬â¢s physical strength or his prowess in sport or his intellectual abilities and vowing to grow up to be just like him. However as the child is exposed to powerful influences
Wednesday, October 16, 2019
Problems of Managing Joint Ventures in China Essay
Problems of Managing Joint Ventures in China - Essay Example The enterprises are busy in making their products and services more and more attractive for the consumers all around the world. They make changes in their products and services in order to meet the requirements of their culture and society. The cultural changes, throughout the world, act as a strong challenge to the enterprises. Efficient cross culture management can guarantee flourishing worldwide operation of international enterprises in the multi-culture and region. The worldwide business dealings are also flourishing in Chinese enterprises. Chinese enterprises have made it an aim to progress and make their name all around the world. Chinese enterprises are making progress in their fields of expertise to promote their abilities and talents throughout the world market. Foreign companies have been working in China for many years, frequently by joint ventures with local firms and usually in the more developed coastal areas. Nowadays, however, Government is now developing the areas with poor infrastructure and encouraging investment in those areas. The poor infrastructure, illiterate public and employers with less knowledge about market economy concepts made it very difficult for the firms existing there and even for th e firms making joint ventures to progress. In the central Shaanxi province, fifty four interviews were planned with the managers in twenty four join ventures clearly shows the prospective hazard in the way of a thriving join venture. As Chinese market is becoming the centre of attention of more and more foreign investors the pitfalls of Chinese market, management and hurdles in its way to success are given proper thought and suggestions are made to solve these problems (Ahlstrom et al. 2003; Beamish, 1993; Child, 1994; Goodall and Warner, 1999; Peng, 2000). It is already known that in the previous twenty five years, almost 85 percent foreign firms, located in China, are sited along the Coastal belt of China (SSB, various years). Since late 1990s, the Chinese government is busy in the developmental process of the areas with weak infrastructure and poor growth rate in order to get rid of the local regional differences. "The Great Western Development Strategy (xibu da kaifa)" was commenced in 1999 with a motive to encourage local and international investment in the country. It was a categorical effort to increase investment in those regions of China, mainly in need but least likely to attract support on their own. U nder its persuasion, an increasing number of foreign firms and joint ventures entered in the underdeveloped hinterland. In 2002, 31,822 foreign ventures had been set up in China's 18 interior districts and one municipality (SSB, 2003, p.678). All the regions carry some importance. In the same way, China's interior is of great importance, without development of those regions China wouldn't be able to progress in the international market. All facilities and technologies must be equally provided in the underdeveloped regions. For this reason, under the 7th Five Year Plan (FYP) (1981-1985), China's economies were separated in to three regions, namely, the Eastern region, the middle region and the Western region (Linge and Forbes, 1990, p.68 and Chen, 2000, pp.9-10; Wei. 2000, p. 1). Traditionally, the Middle and the Western areas have been considered as one large part, the interior (Chen, 2000, p. 10 and Wei, 2000, p. 1). As stated in the 7th Five Year
Personal development and ethics Assignment Example | Topics and Well Written Essays - 2500 words
Personal development and ethics - Assignment Example One develops these over time and many factors influence how theyââ¬â¢re crafted. However good and bad or right and wrong are very broad terms and differ from society to society and within different cultures, races and peoples. There are a whole lot of grey areas and overlapping nuances between the rigidity of good and bad or right and wrong. Perhaps the meaning of these terms may even vary depending on our own experiences. For example we have all been taught that taking another personââ¬â¢s life is wrong. When a murderer who is convicted of mass murder is brought to book many of us may think that he deserves the death penalty, yet somewhere in our hearts we may find the compassion to allow him the option of a life sentence that would possibly allow him to repent and do some good. Consider however that the victim is a loved one, would you then feel any compassion for the murderer? Here then is the difference in each oneââ¬â¢s ethics. So, we may define them as a personal code of conduct or those principles by which one makes choices in life regarding what is right or wrong, good or bad. The process of personal development begins long before we even understand the meaning of the term in its entirety. A baby needs love and care and deprived of these the baby may suffer ill effects that can irreparably warp his/her personal development and lead to personality problems in later life. A young childââ¬â¢s personal development begins, in the home and he/she usually has a role model in whose image the child would like to transform him/her. This image changes as one grows and is usually different at different times in oneââ¬â¢s life. A childââ¬â¢s earliest role model is a parent ââ¬â a picture of a young boy comes to mind proudly proclaiming his fatherââ¬â¢s physical strength or his prowess in sport or his intellectual abilities and vowing to grow up to be just like him. However as the child is exposed to powerful influences
Tuesday, October 15, 2019
Difference Between Romanticism and Transendinlalism in American and British Writers Essay Example for Free
Difference Between Romanticism and Transendinlalism in American and British Writers Essay Difference Between Romanticism and Transendinlalism in American and British Writers The expression Romantic gained currency during its own time, roughly 1780-1850. However, the Romantic era is to identify a period in which certain ideas and attitudes arose, gained the idea of intellectual achievement and became dominant. This is why , they became the dominant mode of expression. Which tells us something else about the Romantic era which expression was perhaps everything to do with them expression in art, music, poetry, drama, literature and philosophy. Romantic ideas arose both as implicit and explicit criticisms of 18th century Enlightenment thought. For the most part, these ideas were generated by a sense of being unable to deal with the dominant ideals of the Enlightenment and of the society that produced them. Which characterized Transendinlalism very differently from that of Romanticism. The difference of Transendinlalism was that it was a literary and philosophical movement, associated with Ralph Waldo Emerson and Margaret Fuller, asserting the existence of an ideal spiritual reality that transcends the empirical and scientific and is knowable through intuition. However, the Romantics thought differently because they that, that romanticism was an artistic and intellectual movement originating in Europe in the late 18th century and characterized by a heightened interest in nature, emphasis on the individuals expression of emotion and imagination, departure from the attitudes and forms of classicism, and rebellion against established social rules and conventions. The Romantics felt all the opinions of the Enlightment were fraught with dangerous errors and oversimplification. Romanticism may then be considered as a critique of the inadequacies of what it held to be Enlightened thought. The difference between these two eras are the British and American writers that have chosen either the path of romanticism or transendinlalism. The characteristics of Romanticism are different to those of Transendinlalism. Romanticism results in part from the libertarian and egalitarian ideals of the French Revolution, the romantic movements had in common only a revolt against the prescribed rules of classicism. The basic aims of romanticism were various: a return to nature and to the belief in the goodness of humanity; the rediscovery of the artist as a supremely individual creator; the development of nationalistic pride; and the exaltation of the senses and emotion over reason and intellect. In addition, romanticism was a philosophical revolt against rationalism. Another difference between those of Romanticism and Transendinlalism are itââ¬â¢s themes that it represents. One of the many themes of romanticism are dreams and visions. The most notable example of the emphasis on dreams and visions in romantic literature is Coleridgeââ¬â¢s poems is ââ¬Å"Kubla Khanâ⬠written in 1816, he claims to have written is during a dream while deeply asleep . While transcribing the lines from his dream, he was interrupted by a visitor, and later claimed that if this interruption had not occurred, the poem would have been much longer. The idea that a person could compose poetry while asleep was a common amongst romantics. Although critics at the time were not particularly enthusiastic about Kubla Khan. Nature had a overwhelming influence during the Romantic Era. In Kubla Khan describes the nature that he is surrounded by; Walls and towers were raised around twice five miles of fertile ground, filled with beautiful gardens and forests. A deep romantic chasm slanted down a green hill, occasionally spewing forth a violent and powerful burst of water, so great that it flung boulders up with it like rebounding hail. The river ran five miles through the woods, finally sinking in tumult to a lifeless ocean. Amid that tumult, in the place as holy and enchanted / As eer beneath a waning moon was haunted / By woman wailing to her demon-lover, Kubla heard ancestral voices bringing prophesies of war. The pleasure-domes shadow floated on the waves, where the mingled sounds of the fountain and the caves could be heard. It was a miracle of rare device, the speaker says, A sunny pleasure-dome with caves of ice! Coleridges is inspired by the beauty and charmingness that nature gives them during the romantic era. Before this period of time another era had began called The Age Of Enlightenment. In the 18th century ââ¬Å" The Enlightenment,â⬠made this movement advocated rationality as a means to establish an authoritative system of ethics, aesthetics, and knowledge. Which then gave the transendinlalism itââ¬â¢s place in this movement. Transendinlalism is a literary and philosophical movement, associated with Ralph Waldo Emerson and Margaret Fuller, asserting the existence of an ideal spiritual reality that transcends the empirical and scientific and is knowable through intuition. It is no coincidence that this movement took off just as the American literary tradition was beginning to blossom. Transcendentalismââ¬âthough inspired by German and British Romanticismââ¬âwas a distinctly American movement in that it was tied into notions of American individualism. In addition to the theme of American democracy, transcendentalist literature also promotes the idea of nature as divine and the human soul as inherently wise. Transcendentalism also had a political dimension, and writers such as Thoreau put their transcendentalist beliefs into action through acts of civil disobedience to the government. The nineteenth century was a volatile one, beginning with the hope and promise of democracy and the development of an American identity and moving towards mass devastation and division by the middle of the century. Slavery and the Civil War, womenââ¬â¢s rights, growing industrialism and class division ââ¬âall of these events were influential and each had a role to play in the transcendentalist movement. Transendinlalism had many themes to those of the Romantics at their time like self- wisdom. Quite simply, Transcendentalism is based on the belief that human beings have self-wisdom and may gain this knowledge or wisdom by tuning in to the ebb and flow of nature. Transcendentalism revolves around the self, specifically the betterment of the self. Where Emerson and his followers differed from earlier philosophical and religious beliefs was in the idea that human beings had natural knowledge and could connect with God directly rather than through an institution such as organized religion. Transcendentalism celebrated the self, an important step in the construction of American identity, better understood as the notion of American individualismââ¬âone of the cornerstones of American democracy. Nature played an important role in the Transcendentalist view. Nature was divine and alive with spirit; indeed, the human mind could read the truths of life in nature. To live in harmony with nature and to allow ones deepest intuitive being to communicate with nature was a source of goodness and inspiration. In fact, writers not only celebrated Americas great landscape, but also constructed the wilderness as a type of dramatic character that illustrated moral law. The desire for an escape from the evils of society and a return to nature became a permanent convention of American literature. Transcendentalist thought emphasized individualism. Only by rejecting the irrelevant dogmas in place and searching for inner truth could one experience the deep intuition of spiritual reality. In relation, Transcendentalism is also very democratic, asserting that the powers of the individual mind and soul are equally available to all people. These powers are not dependent on wealth, gender, background, or education, but on the individuals willingness to release their own imaginative power to realize his or her place in the Oversoul. The obvious results from Transcendentalist efforts are manifest in the intense moral enthusiasm that characterized Transcendental thinkers. Society, with its emphasis on material success, was often seen as a source of corruption. To combat this evil, many Transcendentalists were associated with such moralist groups as the anti-slavery group, the march for womens rights, and other aid societies. Ultimately, some Transcendentalists hoped to reform society by creating an American utopia with a perfect social and political system. The Transcendentalists can be exasperatingly vague in their prescriptions for spiritual transformation, a vagueness which derives principally from their distrust of all forms of ritual and inherited religious forms. The transcendent individual is often a solitary figure, contemplating his soul (and by analogy, the soul of all humanity), and contemplating other souls through the reading of serious literature. But the central recurring theme that emerges is a return to nature, where the artifice and depravity of society cannot reach. Thus Thoreau leaves Concord and heads for Walden Pond to explore the great truths of the natural world. Thus Jones Very, in his poem The Silent, distinguishes between the sounds that strike the ear and those that strike the soul when one walks in the woods: Tis all unheard; that Silent Voice, Whose goings forth unknown to all, Bids bending reed and bird rejoice, And fills with music Natures hall. And in the speechless human heart It speaks, whereer mans feet have trod; Beyond the lips deceitful art, To tell of Him, the Unseen God. â⬠Thus the similarities in the Romantic and Transendinlalism era are ver closely together. For the writers of these eras believed in different yet similar things. For example, nature was one of the similarities of both eras they had marked the world in believing that nature is something that will keep you clam and feel safe like all writers at the time believed in. For romantics believed in intellectual and artistic belief in their writing. Thus they also had many differences for reason over belief this is one of the subjects that the romantics and transcendentalist did not agreed in. During the 18th century their truly was no difference in both the romantic and Transendinlalism era. The only difference was those of the peopleââ¬â¢s writings of this period who made this era last for years.
Monday, October 14, 2019
Crystalline Concrete for Sub Structure Waterproofing
Crystalline Concrete for Sub Structure Waterproofing Crystalline Concrete for Sub Structure Waterproofing: A Literature Review Abstract In recent years, numerous urban areas have suffered flooding. The flood in urban area comes with even more disastrous effects such as health catastrophise in addition to damage to the properties and financial loss. The urban flood leaves behind the flooded basement of houses and other public infrastructures which needs professional attention to solve the problem. Number of techniques are available in the market for the post construction water proofing solutions. However, this review article is focused on current method of integral concrete water proofing method using crystalline waterproofing materials and preventing the sub structure flooding. This article reviews various causes of basement flooding and gives an overview of proprietary characteristics of crystalline materials such as doping quantity, influence on concrete and mortar compressive strength, degree of water tightness/impermeability, reformation of inner structural matrix etc. The benefits of using crystalline materials are illustrated followed by a case study. This literature review article revealed more favourable features of crystalline waterproofing which cannot be ignored. Crystalline waterproofing was came out as the most cost efficient and easy to operate with solution. It does not impart any significant change on the structural properties of the concrete and can be used with varied types of concrete and mortar at different locations. The crystalline concrete is meant to be the future of water proof construction industry and is currently used at many large-scale construction hydro projects to the multi-level basements of high rise structures. Introduction Various metropolitans and small urban areas across the world has suffered from flooding in recent years due to global warming effect. Cities across Canada are no exceptions from such disasters. Metros such as Winnipeg, Toronto, Montreal, Calgary are the victims of severe urban flood disasters. Floods causes millions of dollars damage to the country and leaves financial and health catastrophes behind. In recent years, Canada has suffered most expensive floods in the history in the City of Calgary in Alberta and Greater Toronto Area in Southern Ontario. Flood in the city of Calgary costed almost 5-Billion-dollar loss to the government with 1.7-billion-dollar loss of insured properties [1]. Numerous homes were flooded in Greater Toronto Area in July 2013 and damaged properties worth 940$ million. In 2012, Insurance bureau of Canada revealed very astonishing fact that, almost 51% claims paid to the property owners due to flooded houses were related to the basement flooding. In addition t o financial catastrophes, Severity of flooded basements to the human health cannot be ignored. Damp walls and floors pooled with sewer waters are the best breeding places for various pathogens and hazardous bacteria which can lend damage to respiratory and immunity system. There are several reasons for flooding of basements such as ground water ingress due to water table rise, infiltration of water during heavy rains, sewer back up, drainage failure, etc. which leads to deterioration of basement structure. Soil aggression due to presence of chemicals are added source of active degradation of concrete constituents [2] [3].Ãâà Such added risk of structural degradation of basement structure should be overcome by implying various changes into construction methods and post construction rehabilitation measures. By maintaining the sound structural condition of basement walls and ceiling/floor slabs, risk of basement flooding due to ground water ingress (Pluvial flooding) can be minimized. Chew and De Silva [2] carried out 61 face to face interviews and survey of 987 cases with basement flooding sue to water seepage. The severity of the problem was categorized on Likert scale on 1 to 5 scale where 1 represented very mild, 3 moderate and 5 very severe con dition. Poor joint detailing, cracks and porosity was identified as the main cause of water seepage during construction and after construction stage. I. H. Wong [3] studied the wetness of basement walls due to water seepage in various building of Singapore. it was found that in case of multi-level basement, the bottom most basement was significantly affected by moisture penetration. Numerous techniques have been developed through years for waterproofing of sub surface walls. During construction stage, Chemicals are sprayed on structural components for damp proofing and various membrane sheets are applied on the surface post construction. All of these methods requires extensive supervision, expertise and care during the installation and there are extensive chances of system failure during the installation and due to higher hydrostatic pressure. Post construction waterproofing techniques are more complex as they are employed on late detection and hence requires excavation, temporary retention or even possibly underpinning of adjacent structures and thus such measures cannot be employed while flowing waters [4]. Most dwelling are constructed with sub surface drainages directed towards sum pits where pumps are installed to draw out percolated water to exterior sewer or storm water channels. In case of failure of pump or overflow of exterior system, drainages help wa ter to seep through the walls. Mechanics of Moisture Migration Same as in the case of concrete slab, water/moisture penetrates through the walls due to hydrostatic pressure or capillary action [5]. Hydrostatic water pressure is build up due to presence of high ground water table on the backfill side of the wall. Capillary pores are developed in the soil or the wall itself. Capillary pores help water to elevate from lower to higher heights which is known as the capillary action. Concrete and especially mortar is more vulnerable to capillary action due to presence of already available micro cracks. Third but an uncommon way of the moisture migration is due to water vapour. Water in depth of soil or concrete turns into vapour due to subsequent change in the temperature. This helps vapour to travel through the sub structure walls once enough difference in the vapour pressure is established on both sides. For the prevention of moisture migration, integral crystalline waterproofing can be used with the use of chemical in the concrete mix. Crystalline Concrete Many researchers are working for the complete solution for a water proof concrete which can be applied during the construction process such as an additive mixture in concrete batching plant or can be used as a surface treatment method like a membrane but easy to install. However, the quest of finding an all in one solution is partially over with the development of crystalline concrete which is an integral concrete waterproofing method. The crystalline concrete waterproofing was developed in early 40s and was designed for repairing of concrete. However, the extensive research and product development has made integral crystalline waterproofing as the future of waterproof construction industry. This tested technology of crystalline admixture contains organic and cementitious compounds which gets activated when comes in contact with the water and reacts with unhydrated cement [4]. This reaction develops a needle like structures (As shown in Figure 1) filling the concrete pores or voids otherwise may have acted as capillary pores for the water ingress. In case if the concrete goes further cracking or crack is opened due to movement, the activated material forms crystals to fill these voids and again seals the pores. This hydrophilic admixture also helps unhydrated cement particles to stabilize through the course of time and prevents future existence of capillary pores. Figure 1 Crystalline concrete needle like structures (Courtesy: The National Academic Press) Properties and Characteristics The crystalline admixture is composed of Portland cement, specially treated quartz and active chemicals. The composition of active chemical is kept secret by the manufacturers. However, the waterproofing effect of crystalline material is confirmed in laboratory by using various chemical mixtures. Zhang Yong et al. [6] carried out experimental study to determine the quantity of the doping chemical agent to be used in concrete for crystalline waterproofing effect. Various chemical agents such as complexing agent (denoted as B), Calcium aluminium composite salt (denoted as C), Calcium hydroxide (denoted as D) and Calcium aluminium composite salt 2 (denoted as E) were used throughout the experiment. To determine the water resistivity, two seepage tests were conducted at 14 day and 28 day of casting specimen. Specimen with doping agent denoted as D and B performed the best at 14 and 28 days respectively. These two specimens were further investigated for optimization of doping quantity. Fo llowing Figure 2 shows optimization tests results for doping agents D and B. Zhang Yong et al. [6] also carried out experiments to determine the compressive strength, breaking strength and bonding strength of coating paste and observed increase of compressive and breaking strength with increase in sand-cement ratio however bonding strength decreases with increase in sand-cement ratio (See Figure 3-5). Figure 2 Optimization test results [6] Figure 3 Compressive strength [6] Figure 4 Breaking strength [6] Figure 5 Bond strength [6] The influence of crystalline concrete admixture on the compressive strength of concrete was also studied by Pazderka[7]. The experiments were divided in to two phases, one for concrete and one for mortar. The compression resistance of concrete and mortar has been the topic of discussion since long as the elements in the substructures are designed for load bearing. The investigation of concrete compression test subjected to crystalline admixture added by 2% of cement weight showed no change in the compressive strength result of concrete cubes however, slight deceleration in the hardening process of concrete was observed. In the case of cement mortar, an increase of 25% in compressive strength was observed on 41st day of casting. Figure 6 shows the trend of growth in compressive strength of cement mortar subjected to same weight of crystalline admixture. Figure 6 Growth trend of compressive strength of cement mortar [7] The speed of waterproofing by crystalline admixture is also a subject of claims by various manufacturers as there are no credible research has been carried out to measure the waterproofing speed of crystalline admixtures. Pazderka and Hajkova [8] studied the speed of waterproofing while using the crystalline admixtures. The experiment involved carrying out water pressure tests at different time intervals during the early hydration stage of cement. Xypex Admix C-1000 NF was used as crystalline admixture as it is widely available in the market. Cube specimen casted were subjected to 0.5MPa water pressure for 72 hours and cubes were broken to determine seepage afterwards. The test result data showed that, complete water proofing is achieved on 12th day of curing and seepage boundary was measured at 15 mm from the surface. The concrete was declared ready to carry the water load. Following Figure 7 shows seepage boundaries at various day of intervals. Figure 7 Seepage shapes at various days of intervals [8] W. Keliang et al. [9] studied the impermeability of permeated crystalline concrete by performing impermeability tests. The results showed that use of permeated crystalline material decreases fine cracks in in the mortar matrix and reduces the distribution of pores with diameters larger than 200nm and reduced the distribution of smaller pores having diameter 20nm-100nm. This in turn reduces the most probable diameter of pores available in matrix without permeated crystalline material and hence improves water tightness. Following Figure 8 shows the distribution curve for pores with differential diameter subjected to different dosage of permeated crystalline material. Figure 8 distribution curve for pores with differential diameter subjected to different dosage of permeated crystalline material [9] Reiterman and Baumelt [10] investigated the long-term sorption properties of concrete with crystalline admixture. It was observed that, in the initial stage of curing (7 days), the dosage of crystalline material in concrete mix does not make any change in water tightness as it retards 50% water with 0.5% and 1.0% content of crystalline material. The research suggests matured effectivity of crystalline material on 90 days and suggests past data with more than 50% and 80% reduction in capillary water transportation with same 0.5% and 1.0% content. Crystalline mixtures can also be used as a surface treatment tool as a post construction water proofing measure. In case, the optimum thickness or depth of the crystalline cover is necessary to protect the element from further degradation. Reiterman and Pazderka [11] studied the influence of crystalline coating depth on water transport in concrete structure by electrical resistivity method, water absorption and reliability affected due to construction joints and. The researchers observed significant change in the inner formation of the concrete matrix and confirmed water tightness of the crystalline material particularly in construction joint areas. Benefits There are several benefits of using crystalline concrete waterproofing can be drawn from studying the literature. It can be used during construction and after construction measure. Crystalline material easily penetrates in to the concrete pores and becomes an inherent part of the concrete which cannot be detached like membrane sheets. Being a hydrophilic material, it gets activated when come to contact with water or moisture. Crystalline materials are readily available from different manufacturers and are easy to store and install. Crystalline materials can be applied on different types of concrete and mortars from outside or inside. Crystalline waterproofing is a cost effective long term solution for the substructure water proofing and hence being a successful and sustainable solution, it is increasingly used in large hydro projects around the world. Case study: AIG headquarters London The American International Group Inc. (AIG) is located on Fenchurch Street London. The building consists of 14 storey structure with two levels of basements. The first level was meant to host mechanical and electrical facilities and second level was supposed to be used for car parking and document storage [12]. The construction of the building was followed by a very tight time schedule and hence, the sub-contractor Duffy construction Ltd. used the integral concrete waterproofing technique and saved a moth. Pudlo concentrated integral concrete waterproofing powder was used with C40 grade of concrete, cement content of 350 Kg/m3, water/cement ratio of 0.4 and slump height was 100mm. The concrete was supplied by London Concrete. Water proofing agent with concentration of 8 Kg/m3 was used and alkali content was kept below 2.45 Kg/m3 reducing the alkali silica reaction. The modified concrete was used to construct a 1.2m thick raft for basement and located 7m below ground supported on pile foundation. High density bentonite based sealer was used in joint as an added measure for water tightness. These modifications in concrete resulted into 90% reduction in water absorption and more than 50% reduction in water penetration under pressure while improving freeze-thaw, chloride and oxygen diffusion and sulphate resistance. Mixture also developed increased compressive and flexural strength with reduced shrinkage/wetting expansion, efflorescence, leaching and carbonation rate. Conclusion Flooded basements are the most common property claims filled by home owners and costs millions of dollars loss to the insurance industry and the economy of the country. there are various types of post construction techniques are available for water proofing such as membrane sheets or chemical sprays etc. out of which crystalline concrete water proofing method of integral water proofing was observed to serve best. Crystalline materials are available in various mixtures which can be used during construction as an additive to the mortar or concrete mix and it can also be used as chemical spray for post construction water proofing. It is observed that, crystalline concrete when comes in contact with water or moisture, it gets activated and forms needle like structure inside the structural matrix. These formation fills harmful pores of diameter larger than 200nm and increases the distribution of smaller diameter pores ranging from 20nm-100nm. The influence of crystalline material on compr essive strength of concrete is almost negligible. However, Compressive strength of mortar gets increased by 25 on 41st day of casting. The structural matrix achieves full water tightness on 7th day of casting and becomes ready to bear the water load. The long-term effects of crystalline waterproofing are observed more favourable than short term effect neglecting the misconception of increased dosage requirement. [1] D. Sandlink, Urban flooding and ground-related homes in canada: An overview, in Journal of flood risk management 6th international conference on flood management, Sao Paulo Brazil, 2016. [2] M. Chew and N. De Silva, Benchmarks to minimize water leakages in basements, Structural Survey, Vol. 21, no. 4, pp. 131-145, 2003. [3] I. Wong, Experience with waterproofness of basements constructed of concrete diaphragm wall in singapore, Tunneling and underground space technology, Vol. 12, no. 4, pp. 491-495, 1998. [4] C. Deckard, Rethinking waterproofing for subsurface structures, in Fifth Forensic Engineering Congress, Washington D.C., 2009. [5] R. W. Day, Moisture penetration of concrete floor slabs, basement walls and flat slab ceilings, Practice periodical on structural design and construction, Vol. 1, no. 4, pp. 104-107, November 1996. [6] Y. Zhang, X. Du, Y. Li, F. Yang and Z. Li, Research on cementitious capillary crystalline waterproofing coating for underground concrete works, Advanced Materials Research, Vols. 450-451, pp. 286-290, 2012. [7] J. Pazderka, The crystalline admixture effect on concrete and cement mortar compressive strength, Key Engineering Materials, Vol. 722, pp. 87-91, 2017. [8] J. Pazderka and E. Hajkova, The speed of the crystalline admixtures waterproofing, Key Engineering Materials, Vol. 722, pp. 108-112, 2016. [9] K. Wang, T. Hu and S. Xu, Influence of permeated crystalline waterproof materials on impermeability of concrete, Advanced Material Research, Vols. 446-449, pp. 954-960, 2012. [10] P. Reiterman and V. Baumelt, Long-term sorption properties of mortars modified by crystallizing, Advanced Material Research, Vol. 1054, pp. 71-74, 2014. [11] P. Reiterman and J. Pazderka, Crystalline coating and its influence on the water transportat in concrete, Advances in civil engineering, Vol. 2016, pp. 1-8, 2016. [12] M. Phenna, A waterproof basement for AIG headquarters London, London: Concrete Magazine, 2004.
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