Concrete creep and shrinkage strain obtained in constant temperature and constant humidity rooms are different from those observed under actual conditions. Most creep and shrinkage strain prediction equations predict constant temperature and constant relative humidity. The effects of temperature history and relative humidity changes in the atmosphere are not considered in these equations. In this study, the effect of a change in atmosphere on creep and shrinkage strain is discussed. It is shown that concrete creep and shrinkage strain in actual ambient conditions are influenced by the concrete casting season. Creep and shrinkage strain of concrete cast in winter are much bigger than those of concrete cast in summer. The significance of considering the effect of environmental change on concrete creep and shrinkage strain is emphasized in this paper.
{"title":"Effect of Temperature and Relative Humidity on Concrete Creep and Shrinkage","authors":"K. Sakata, T. Ayano","doi":"10.14359/6085","DOIUrl":"https://doi.org/10.14359/6085","url":null,"abstract":"Concrete creep and shrinkage strain obtained in constant temperature and constant humidity rooms are different from those observed under actual conditions. Most creep and shrinkage strain prediction equations predict constant temperature and constant relative humidity. The effects of temperature history and relative humidity changes in the atmosphere are not considered in these equations. In this study, the effect of a change in atmosphere on creep and shrinkage strain is discussed. It is shown that concrete creep and shrinkage strain in actual ambient conditions are influenced by the concrete casting season. Creep and shrinkage strain of concrete cast in winter are much bigger than those of concrete cast in summer. The significance of considering the effect of environmental change on concrete creep and shrinkage strain is emphasized in this paper.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125436691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The authors have proposed a partially pre-cooling system for massive structures, such as gravity concrete dams. In this paper the effectiveness of the proposed method is discussed using finite element analysis. In the ordinary pre-cooling system, pre-cooled concrete is placed in the entire region (width and depth) of a massive structure. In the proposed system, pre-cooled concrete is placed only in the surface layer. In order to evaluate the effectiveness of this system, a thermal stress analysis was conducted by the finite element method. The key parameters were the dimensions of the cooling system and cooling temperatures. The results show that the proposed system is rather more effective than the conventional cooling system in terms of the thermal stress condition of massive concrete structures. In addition, a cost benefit is expected, as the cost of the pre-cooling system is in proportion to the volume of concrete to be cooled.
{"title":"Effectiveness of Partially Cooling System for Massive Concrete Structures","authors":"M. Eto, K. Maruyama, S. Ono","doi":"10.14359/10135","DOIUrl":"https://doi.org/10.14359/10135","url":null,"abstract":"The authors have proposed a partially pre-cooling system for massive structures, such as gravity concrete dams. In this paper the effectiveness of the proposed method is discussed using finite element analysis. In the ordinary pre-cooling system, pre-cooled concrete is placed in the entire region (width and depth) of a massive structure. In the proposed system, pre-cooled concrete is placed only in the surface layer. In order to evaluate the effectiveness of this system, a thermal stress analysis was conducted by the finite element method. The key parameters were the dimensions of the cooling system and cooling temperatures. The results show that the proposed system is rather more effective than the conventional cooling system in terms of the thermal stress condition of massive concrete structures. In addition, a cost benefit is expected, as the cost of the pre-cooling system is in proportion to the volume of concrete to be cooled.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126280205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
About 20 million cubic meters of used timber are discharged every year from demolished buildings, mainly wooden houses, in Japan. The authors have carried out a study on recycling used timber as wood-chip concrete. The experiment was carried out as follows. First, the wood chips were filled into a steel mold to achieve the desired packing ratio with a compressive stress of 0.5-1.0 MPa. Then, fresh cement paste was injected into the mold to make the specimens. The densities of the wood-chip concrete in this case generally fall into the range of 920 kg/cu m to 1250 kg/cu m. To evaluate the performance of the wood-chip concrete, bending strength, compressive strength, drying weight loss and shrinkage, thermal conductivity, and thermal expansion were tested. Furthermore, two types of artificial lightweight aggregate were added to the wood-chip mold and cement paste simultaneously to reduce the densities of the concrete, and the compression of the wood chips for packing was not needed in the production process. The densities of the wood-chip concretes with the lightweight aggregates were about 780 kg/cu m to 920 kg/cu m. After these tests, it became clear that the wood-chip concrete will be suitable for use as a building material for partition walls, floor joists, floor boards, etc.
{"title":"Study on Wood Chip Concrete with Used Timber","authors":"Y. Kasai, M. Kawamura, Jiandong Zhou","doi":"10.14359/6079","DOIUrl":"https://doi.org/10.14359/6079","url":null,"abstract":"About 20 million cubic meters of used timber are discharged every year from demolished buildings, mainly wooden houses, in Japan. The authors have carried out a study on recycling used timber as wood-chip concrete. The experiment was carried out as follows. First, the wood chips were filled into a steel mold to achieve the desired packing ratio with a compressive stress of 0.5-1.0 MPa. Then, fresh cement paste was injected into the mold to make the specimens. The densities of the wood-chip concrete in this case generally fall into the range of 920 kg/cu m to 1250 kg/cu m. To evaluate the performance of the wood-chip concrete, bending strength, compressive strength, drying weight loss and shrinkage, thermal conductivity, and thermal expansion were tested. Furthermore, two types of artificial lightweight aggregate were added to the wood-chip mold and cement paste simultaneously to reduce the densities of the concrete, and the compression of the wood chips for packing was not needed in the production process. The densities of the wood-chip concretes with the lightweight aggregates were about 780 kg/cu m to 920 kg/cu m. After these tests, it became clear that the wood-chip concrete will be suitable for use as a building material for partition walls, floor joists, floor boards, etc.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130871622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Green Concrete is a concrete on which plants such as grasses and bushes directly grow up. It is utilized for increasing the amount of the green around buildings and civil structures. It consists of no-fines concrete, water retentive material in the voids and a thin soil layer sprayed on the surface. The no-fines concrete is made of single size crushed stone and low alkaline cement paste. Chopped peat moss which retains water and fertilizer is used to fill in the voids. Seeds mixed with the soil germinate, take root into the voids and grow up. In this paper the results of studies of the relationship between the strength and the void ratio of concrete, and the effects of cement types on the alkalinity leached from hardened cement are presented. Plant growth performance of the Green Concrete is also presented based on planting tests using lawns and actual applications. The optimum void ratio of concrete was approximately 25-30% when the compressive strength was approximately 10-15 N/sq mm. In this condition of concrete, it is demonstrated that herbaceous plants and some kinds of trees sufficiently grow on the Green Concrete.
{"title":"Properties and Performance of Green Concrete","authors":"K. Yanagibashi, T. Yonezawa","doi":"10.14359/6036","DOIUrl":"https://doi.org/10.14359/6036","url":null,"abstract":"Green Concrete is a concrete on which plants such as grasses and bushes directly grow up. It is utilized for increasing the amount of the green around buildings and civil structures. It consists of no-fines concrete, water retentive material in the voids and a thin soil layer sprayed on the surface. The no-fines concrete is made of single size crushed stone and low alkaline cement paste. Chopped peat moss which retains water and fertilizer is used to fill in the voids. Seeds mixed with the soil germinate, take root into the voids and grow up. In this paper the results of studies of the relationship between the strength and the void ratio of concrete, and the effects of cement types on the alkalinity leached from hardened cement are presented. Plant growth performance of the Green Concrete is also presented based on planting tests using lawns and actual applications. The optimum void ratio of concrete was approximately 25-30% when the compressive strength was approximately 10-15 N/sq mm. In this condition of concrete, it is demonstrated that herbaceous plants and some kinds of trees sufficiently grow on the Green Concrete.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130396778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Nakamoto, Togawa, T.Miyagawa, M. Fujii, S. Nagaoka
It is essential that concrete structures should withstand the conditions for which they have been designed for long periods of time. The lack of durability may be caused either by the environment to which the concrete is exposed or by the concrete itself. In this study, the resistance to freezing and thawing of high-slag content concrete (HSC concrete) is discussed for the purpose of utilizing ground granulated blast furnace slag (GGBS) as an ingredient of cement. The slag content in cement ranged from 0 to 95% by weight of total cementitious materials and the fineness of slag was 816 sq m/kg. The resistance of air entrained (AE) concrete with a slag content of 70% was superior or comparable to that of slag free concrete, whereas AE concretes had questionable performance in the case of slag content of 85%, and had less ability in the case of 95% slag content with respect to freezing and thawing resistance. HSC concretes could have satisfactory high resistance to freezing and thawing by using an air-entraining high range water-reducing admixture (AEHW admixture), even if the slag content was 95%. Thus, the concrete with AEHW admixture, which are called SP concretes, would be recommended for freezing and thawing conditions with respect to the use of HSC concrete.
{"title":"Freezing and Thawing Resistance of High Slag Content Concrete","authors":"J. Nakamoto, Togawa, T.Miyagawa, M. Fujii, S. Nagaoka","doi":"10.14359/6086","DOIUrl":"https://doi.org/10.14359/6086","url":null,"abstract":"It is essential that concrete structures should withstand the conditions for which they have been designed for long periods of time. The lack of durability may be caused either by the environment to which the concrete is exposed or by the concrete itself. In this study, the resistance to freezing and thawing of high-slag content concrete (HSC concrete) is discussed for the purpose of utilizing ground granulated blast furnace slag (GGBS) as an ingredient of cement. The slag content in cement ranged from 0 to 95% by weight of total cementitious materials and the fineness of slag was 816 sq m/kg. The resistance of air entrained (AE) concrete with a slag content of 70% was superior or comparable to that of slag free concrete, whereas AE concretes had questionable performance in the case of slag content of 85%, and had less ability in the case of 95% slag content with respect to freezing and thawing resistance. HSC concretes could have satisfactory high resistance to freezing and thawing by using an air-entraining high range water-reducing admixture (AEHW admixture), even if the slag content was 95%. Thus, the concrete with AEHW admixture, which are called SP concretes, would be recommended for freezing and thawing conditions with respect to the use of HSC concrete.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129297597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The pressure of expansive concrete under confinement was investigated by the finite element method (FEM). It was found that it was possible to estimate the pressure of expansive concrete by simple elastic calculation using FEM where the elastic modulus was assumed to be 1-3 GPa, which was an order of magnitude lower than that of normal concrete. Experimental data giving the pressure of expansive concrete under confinement was successfully explained by the FEM calculation. It is demonstrated that FEM analysis is a useful tool to estimate the pressure of expansive concrete under various confinement conditions.
{"title":"FEM Pressure Estimation of Confined Expansive Concrete","authors":"K. Yamada, T. Harada, K. Soeda, A. Watanabe","doi":"10.14359/6077","DOIUrl":"https://doi.org/10.14359/6077","url":null,"abstract":"The pressure of expansive concrete under confinement was investigated by the finite element method (FEM). It was found that it was possible to estimate the pressure of expansive concrete by simple elastic calculation using FEM where the elastic modulus was assumed to be 1-3 GPa, which was an order of magnitude lower than that of normal concrete. Experimental data giving the pressure of expansive concrete under confinement was successfully explained by the FEM calculation. It is demonstrated that FEM analysis is a useful tool to estimate the pressure of expansive concrete under various confinement conditions.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130823831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Fujiki, K. Kokubu, T. Hosaka, T. Umehara, N. Takaha
One method of confirming in a laboratory the resistance of concrete to frost damage is freezing and thawing testing. The Japan Society of Civil Engineers (JSCE) established a standard method, JSCE G 501, in line with American Society for Testing and Materials (ASTM) C 666 Procedure A. However, whether this method accurately evaluates the resistance of actual concrete structures to frost damage should be open to further discussion. The test method needs modifications particularly for lightwieght aggregate concrete. With aggregate being prewetted in the production process, lightweight aggregate concrete in Japan is doomed to be evaluated as having low durability by the JSCE-specified laboratory tests, as such concrete tends to break up during testing by the freezing expansion of water in critically saturated aggregate. However, a number of actual structures, such as bridge decks where drying proceeds after placing, have exhibited sufficient durability. The authors verify the durability of lightweight aggregate concrete against frost damage by freezing and thawing tests on specimens containing lightweight aggregate with the degree of saturation being modified by drying, as well as by the measurement of the degree of drying and frost resistance of concrete specimens exposed to an outdoor environment in winter.
在实验室中确认混凝土抗冻破坏的一种方法是冻融试验。日本土木工程师学会(JSCE)根据美国材料试验学会(ASTM) C 666程序a，制定了JSCE G 501标准方法。然而，该方法是否能准确评估实际混凝土结构的抗冻损能力，还有待进一步讨论。试验方法需要修改，特别是对于轻骨料混凝土。由于骨料在生产过程中被预湿，日本的轻骨料混凝土在jsce指定的实验室测试中注定要被评为耐久性低，因为这种混凝土在测试过程中容易因临界饱和骨料中水的冻结膨胀而破裂。然而，一些实际的结构，如桥面，在放置后进行干燥，已经表现出足够的耐久性。作者通过对含有轻骨料的试件进行冻融试验，并通过干燥改变其饱和度，以及测量冬季暴露在室外环境中的混凝土试件的干燥程度和抗冻性，验证了轻骨料混凝土的抗冻损伤耐久性。
{"title":"Freezing and Thawing Resistance of Lightweight Aggregate Concrete","authors":"E. Fujiki, K. Kokubu, T. Hosaka, T. Umehara, N. Takaha","doi":"10.14359/6074","DOIUrl":"https://doi.org/10.14359/6074","url":null,"abstract":"One method of confirming in a laboratory the resistance of concrete to frost damage is freezing and thawing testing. The Japan Society of Civil Engineers (JSCE) established a standard method, JSCE G 501, in line with American Society for Testing and Materials (ASTM) C 666 Procedure A. However, whether this method accurately evaluates the resistance of actual concrete structures to frost damage should be open to further discussion. The test method needs modifications particularly for lightwieght aggregate concrete. With aggregate being prewetted in the production process, lightweight aggregate concrete in Japan is doomed to be evaluated as having low durability by the JSCE-specified laboratory tests, as such concrete tends to break up during testing by the freezing expansion of water in critically saturated aggregate. However, a number of actual structures, such as bridge decks where drying proceeds after placing, have exhibited sufficient durability. The authors verify the durability of lightweight aggregate concrete against frost damage by freezing and thawing tests on specimens containing lightweight aggregate with the degree of saturation being modified by drying, as well as by the measurement of the degree of drying and frost resistance of concrete specimens exposed to an outdoor environment in winter.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124976941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It is anticipated that coal-fired thermal power stations will increase in Japan and that the discharged amount of coal ashes, which are industrial by-products, will rapidly increase in the future. In order to effectively use the bottom ash discharged from coal-fired thermal power stations, concrete which substitutes bottom ash from 0 to 40% by volume for fine aggregate was investigated in this study. The compressive strength, tensile strength, freezing and thawing resistance, and abrasion resistance of the concrete were examined. The results of the concrete strength tests indicate that the compressive strength and tensile strength of bottom ash concrete generally increases with the increase of replacement ratio of fine aggregate and curing age. The freezing and thawing resistance of concrete using bottom ash is lower than that of ordinary concrete and the abrasion resistance of bottom ash concrete is higher than that of ordinary concrete. The use of bottom ash in amounts of 10 to 40% as replacement for fine aggregate is effective in improving the concrete properties except for the freezing and thawing resistance.
{"title":"Strength and Durability of Concrete Using Bottom Ash as Replacement for Fine Aggregate","authors":"T. Bakoshi, K. Kohno, S. Kawasaki, N. Yamaji","doi":"10.14359/6037","DOIUrl":"https://doi.org/10.14359/6037","url":null,"abstract":"It is anticipated that coal-fired thermal power stations will increase in Japan and that the discharged amount of coal ashes, which are industrial by-products, will rapidly increase in the future. In order to effectively use the bottom ash discharged from coal-fired thermal power stations, concrete which substitutes bottom ash from 0 to 40% by volume for fine aggregate was investigated in this study. The compressive strength, tensile strength, freezing and thawing resistance, and abrasion resistance of the concrete were examined. The results of the concrete strength tests indicate that the compressive strength and tensile strength of bottom ash concrete generally increases with the increase of replacement ratio of fine aggregate and curing age. The freezing and thawing resistance of concrete using bottom ash is lower than that of ordinary concrete and the abrasion resistance of bottom ash concrete is higher than that of ordinary concrete. The use of bottom ash in amounts of 10 to 40% as replacement for fine aggregate is effective in improving the concrete properties except for the freezing and thawing resistance.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125343343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper describes a basic study on the development of a new method to judge the saturated surface-dry condition of fine aggregates. The new method is based on the idea that the electric resistance of a sample depends on the moisture content of the sample. The relationship of the electric resistance with the moisture content of a sample is directly and radically changed by the existence of water on the surfaces of the particles. This becomes clearer when an electrolyte is added to the sample. The relationships between the electric resistance and the moisture content of a sample were investigated for various types of fine aggregates when an electrolyte was added. This relationship shows radical changes in the electric resistance near the saturated surface-dry condition. The chemical compositions of a sample do not influence the relationship of the electric resistance with the total moisture content of the sample. The applicability of the electric resistance test will be confirmed if the data of specimens with various physical properties will be investigated statistically.
{"title":"Basic Study on the New Testing Method of Judging the Saturated Surface Dry Conditions of Fine Aggregates","authors":"A. Ueno, K. Kokubu, H. Ohga","doi":"10.14359/6057","DOIUrl":"https://doi.org/10.14359/6057","url":null,"abstract":"This paper describes a basic study on the development of a new method to judge the saturated surface-dry condition of fine aggregates. The new method is based on the idea that the electric resistance of a sample depends on the moisture content of the sample. The relationship of the electric resistance with the moisture content of a sample is directly and radically changed by the existence of water on the surfaces of the particles. This becomes clearer when an electrolyte is added to the sample. The relationships between the electric resistance and the moisture content of a sample were investigated for various types of fine aggregates when an electrolyte was added. This relationship shows radical changes in the electric resistance near the saturated surface-dry condition. The chemical compositions of a sample do not influence the relationship of the electric resistance with the total moisture content of the sample. The applicability of the electric resistance test will be confirmed if the data of specimens with various physical properties will be investigated statistically.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114238771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper discusses the mechanism of the setting shrinkage of polymer concrete with liquid resin mainly composed of methyl methacrylate (MMA-PC) and reports the study results on the method for reducing the setting shrinkage. The setting shrinkage is classified into two large categories, that is, shrinkage due to polymerization and shrinkage caused by temperature decrease after the maximum temperature is reached. The shrinkage amount due to temperature decrease is in proportion to the liquid resin content. The authors demonstrated that the shrinkage due to polymerization significantly varies with the formation state of matrix of liquid resin with filler. For reducing the shrinkage, it is effective to confine the shrinking strain by adding fibers and modifying the filler properties to limit the volume change due to polymerization.
{"title":"Evaluation of the Setting Shrinkage of MMA Polymer Concrete","authors":"A. Kawamura, M. Kuromoto, T. Iwai","doi":"10.14359/6070","DOIUrl":"https://doi.org/10.14359/6070","url":null,"abstract":"This paper discusses the mechanism of the setting shrinkage of polymer concrete with liquid resin mainly composed of methyl methacrylate (MMA-PC) and reports the study results on the method for reducing the setting shrinkage. The setting shrinkage is classified into two large categories, that is, shrinkage due to polymerization and shrinkage caused by temperature decrease after the maximum temperature is reached. The shrinkage amount due to temperature decrease is in proportion to the liquid resin content. The authors demonstrated that the shrinkage due to polymerization significantly varies with the formation state of matrix of liquid resin with filler. For reducing the shrinkage, it is effective to confine the shrinking strain by adding fibers and modifying the filler properties to limit the volume change due to polymerization.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126856693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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