Automated production of precast polymer concrete construction components is presented. Both batchwise and continuous production are discussed, and examples of both techniques are shown. Automated on-site application and execution systems allow benefits to be taken of the specific features of polymer-cement concrete. Automated execution of overlays, tunnels, porous polymer-cement concrete pavements and polymer-cement shotcrete are presented as examples.
{"title":"Developments in Automated Production Application Systems for Polymer Concrete","authors":"D. Gemert, K. Leuven","doi":"10.14359/6072","DOIUrl":"https://doi.org/10.14359/6072","url":null,"abstract":"Automated production of precast polymer concrete construction components is presented. Both batchwise and continuous production are discussed, and examples of both techniques are shown. Automated on-site application and execution systems allow benefits to be taken of the specific features of polymer-cement concrete. Automated execution of overlays, tunnels, porous polymer-cement concrete pavements and polymer-cement shotcrete are presented as examples.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"103 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":"132065707","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}
A comprehensive experimental program was designed in order to investigate the mechanical and durability properties of high performance lightweight concrete. The concrete mixture was prepared in order to obtain a specific value of the compressive strength at 28 days of age (75 MPa). Testing was carried out on a large number of lightweight concrete specimens. The following properties were investigated: compressive, flexural and splitting-tensile strength, modulus of elasticity, fracture parameters, concrete-steel bond properties, drying shrinkage and durability properties. The test results show that high-performance lightweight concrete has considerable potential for the precast/prestressed industry.
{"title":"High-Performance Lightweight Concrete for the Precast Prestressed Concrete Industry","authors":"F. Curcio, D. Galeota, A. Gallo, M. M. Giammatteo","doi":"10.14359/6051","DOIUrl":"https://doi.org/10.14359/6051","url":null,"abstract":"A comprehensive experimental program was designed in order to investigate the mechanical and durability properties of high performance lightweight concrete. The concrete mixture was prepared in order to obtain a specific value of the compressive strength at 28 days of age (75 MPa). Testing was carried out on a large number of lightweight concrete specimens. The following properties were investigated: compressive, flexural and splitting-tensile strength, modulus of elasticity, fracture parameters, concrete-steel bond properties, drying shrinkage and durability properties. The test results show that high-performance lightweight concrete has considerable potential for the precast/prestressed industry.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"228 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":"129568143","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}
Two aspects of research concerning the self compacting concrete techniques have been extensively carried out in Japan. One aspect is to find a systematic way to evaluate the consistency experimentally. The other is to seek a theoretical way to predict the properties. Thus for the first goal, in this paper three kinds of methods including the dragging ball viscometer test, the slump flow test and the O75 funnel test were proposed to investigate the influence of concrete mixture proportions on the consistency of viscous agent series self compacting concrete. For the second goal, a numerical approach was initially proposed to simulate the behavior of self compacting concrete called Modified Distinct Element Method (MDEM). The applicability of MDEM is verified by comparing the simulation results with the experimental results of the above three types of tests.
{"title":"Experimental Evaluation and Theoretical Simulation of Self Compacting Concrete by the Modif ied Distinct Element Method (MDEM)","authors":"H. Chu, A. Machida","doi":"10.14359/6068","DOIUrl":"https://doi.org/10.14359/6068","url":null,"abstract":"Two aspects of research concerning the self compacting concrete techniques have been extensively carried out in Japan. One aspect is to find a systematic way to evaluate the consistency experimentally. The other is to seek a theoretical way to predict the properties. Thus for the first goal, in this paper three kinds of methods including the dragging ball viscometer test, the slump flow test and the O75 funnel test were proposed to investigate the influence of concrete mixture proportions on the consistency of viscous agent series self compacting concrete. For the second goal, a numerical approach was initially proposed to simulate the behavior of self compacting concrete called Modified Distinct Element Method (MDEM). The applicability of MDEM is verified by comparing the simulation results with the experimental results of the above three types of tests.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"168 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":"116592492","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}
A new method is proposed for the preparation of specimens of high fluidity concrete with excellent flowability and segregation resistance that can not be fully controlled by the current Japanese Industrial Standard. Procedures recommended are: (1) Slump cone should be filled in three equally divided volumes followed by rodding of 5 strokes at each layer; (2) Flow time recommended for quality control should be in 5 to 10 seconds; and (3) Cylinder mold phi 10 x 20 cm for the compressive strength test should be filled in two equally divided volumes followed by a rodding of five strokes at each layer, considering coarse aggregate content and stability of mechanical properties.
{"title":"Effects of Specimen Preparation on the Properties of Fresh and Hardened High Fluidity Concretes","authors":"H. Takenaka, M. Kakizaki, Y. Abe, M. Okada","doi":"10.14359/6063","DOIUrl":"https://doi.org/10.14359/6063","url":null,"abstract":"A new method is proposed for the preparation of specimens of high fluidity concrete with excellent flowability and segregation resistance that can not be fully controlled by the current Japanese Industrial Standard. Procedures recommended are: (1) Slump cone should be filled in three equally divided volumes followed by rodding of 5 strokes at each layer; (2) Flow time recommended for quality control should be in 5 to 10 seconds; and (3) Cylinder mold phi 10 x 20 cm for the compressive strength test should be filled in two equally divided volumes followed by a rodding of five strokes at each layer, considering coarse aggregate content and stability of mechanical properties.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"21 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":"128532904","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}
A. Yasumoto, Y. Edamatsu, M. Mizukoshi, S. Nagaoka
This study looked at the effects of powdered additives used in conjunction with self-compacting concrete and the varying resistance levels to shrinkage crack due to autogenous and drying shrinkage. Resistance was estimated by comparing the cracking ages of the concrete under restrained conditions. The powdered materials used were normal portland cement, low-heat portland cement, portland blast furnace slag cement, and two blends of normal portland cement and limestone powder (the blending volume ratios of limestone powder were 30% and 55%). From the results of the experiments, it became clear that the resistance level of self-compacting concrete to shrinkage crack was quite different depending on the type of powdered materials used.
{"title":"A Study on the Shrinkage Crack Resistance of Self-Compacting Concrete","authors":"A. Yasumoto, Y. Edamatsu, M. Mizukoshi, S. Nagaoka","doi":"10.14359/6066","DOIUrl":"https://doi.org/10.14359/6066","url":null,"abstract":"This study looked at the effects of powdered additives used in conjunction with self-compacting concrete and the varying resistance levels to shrinkage crack due to autogenous and drying shrinkage. Resistance was estimated by comparing the cracking ages of the concrete under restrained conditions. The powdered materials used were normal portland cement, low-heat portland cement, portland blast furnace slag cement, and two blends of normal portland cement and limestone powder (the blending volume ratios of limestone powder were 30% and 55%). From the results of the experiments, it became clear that the resistance level of self-compacting concrete to shrinkage crack was quite different depending on the type of powdered materials used.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"51 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":"129634943","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 durability and strength characteristics of high-volume fly ash concrete were studied in order to utilize fly ash, an industrial by-product from coal fired thermal power plants, as a typical admixture for concrete. The results of this study are as follows: (1) The strength development of high-volume fly ash concrete is higher than that of conventional concrete; (2) There is an optimum mixing ratio of fly ash, in which the compressive strength reaches a maximum level; (3) Freezing and thawing resistance of high-volume fly ash concrete is almost the same as that of conventional concrete; (4) Abrasion resistance, durability in marine environment, and water-tightness are improved by the use of high-volume fly ash; and (5) Adiabatic temperature rise can be reduced compared with that of concrete without fly ash.
{"title":"Investigations on Durability of High-Volume Fly Ash Concrete","authors":"N. Kawaguchi, K. Kohno, Y. Kurose, T. Bakoshi","doi":"10.14359/6069","DOIUrl":"https://doi.org/10.14359/6069","url":null,"abstract":"The durability and strength characteristics of high-volume fly ash concrete were studied in order to utilize fly ash, an industrial by-product from coal fired thermal power plants, as a typical admixture for concrete. The results of this study are as follows: (1) The strength development of high-volume fly ash concrete is higher than that of conventional concrete; (2) There is an optimum mixing ratio of fly ash, in which the compressive strength reaches a maximum level; (3) Freezing and thawing resistance of high-volume fly ash concrete is almost the same as that of conventional concrete; (4) Abrasion resistance, durability in marine environment, and water-tightness are improved by the use of high-volume fly ash; and (5) Adiabatic temperature rise can be reduced compared with that of concrete without fly ash.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"17 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":"114370163","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 development and evaluation of chemical admixtures requires experimental verification of many admixture samples in the laboratory prior to testing the most promising formulations in concrete. Since quantities of new admixture formulations are usually limited, it is necessary to carry out small-scale tests on fresh cement pastes and mortars. The large number of test methods used by individual researchers makes it difficult to compare results from different laboratories. In an attempt to solve this comparability problem, an advanced methodology for testing of water-reducing admixtures has been developed and is discussed in this paper. This methodology is based on studying the properties of fresh cement-water systems, namely pastes and mortars, with or without the addition of a chemical admixture. It includes and modifies some traditional tests such as the Vicat test for cement pastes and the flow test for cement mortars plus some more recently developed tests such as the mini-slump test. It also includes some new test methods such as the torque test and the mini-flow test. The applicability of the new set of test methods was examined during the evaluation of lignosulphonates as water-reducing admixtures for concrete. The determination of rheological properties, air entrainment and set retardation was conducted on cement pastes and mortars. The values describing the plasticity/fluidity, air content, and time of setting were obtained by different methods and under different conditions. The results were then compared and their interpretation is discussed. The methodology presented here is suitable for preliminary evaluation of concrete admixtures. Incorporation of these test methods into national and international standards is suggested.
{"title":"Advances in Evaluation of Lignosulphonates as Concrete Admixtures","authors":"J. Zhor, T. Bremner","doi":"10.14359/6084","DOIUrl":"https://doi.org/10.14359/6084","url":null,"abstract":"The development and evaluation of chemical admixtures requires experimental verification of many admixture samples in the laboratory prior to testing the most promising formulations in concrete. Since quantities of new admixture formulations are usually limited, it is necessary to carry out small-scale tests on fresh cement pastes and mortars. The large number of test methods used by individual researchers makes it difficult to compare results from different laboratories. In an attempt to solve this comparability problem, an advanced methodology for testing of water-reducing admixtures has been developed and is discussed in this paper. This methodology is based on studying the properties of fresh cement-water systems, namely pastes and mortars, with or without the addition of a chemical admixture. It includes and modifies some traditional tests such as the Vicat test for cement pastes and the flow test for cement mortars plus some more recently developed tests such as the mini-slump test. It also includes some new test methods such as the torque test and the mini-flow test. The applicability of the new set of test methods was examined during the evaluation of lignosulphonates as water-reducing admixtures for concrete. The determination of rheological properties, air entrainment and set retardation was conducted on cement pastes and mortars. The values describing the plasticity/fluidity, air content, and time of setting were obtained by different methods and under different conditions. The results were then compared and their interpretation is discussed. The methodology presented here is suitable for preliminary evaluation of concrete admixtures. Incorporation of these test methods into national and international standards is suggested.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"112 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":"124770738","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}
Flowing concrete is a highly flowable and segregation resistant concrete. Shrinkage of the concrete at early ages up to 24 hours under a constant air flow of 8 m/s starting at the age of 2 hours, and crack propagation of the concrete in a restricted form with a thickness of 50 mm have been studied. The experiments were done by controlling the following four mixture parameters: (1) Water-cement ratio: 0.60, 0.45, 0.35, 0.30 and 0.27; (2) Unit amount of water: 185, 175 and 170 kg/cu m; (3) Type of cement: normal, high early strength and belite portland cement; and (4) Type of inorganic admixture: a ground granulated blast furnace slag and a fly ash and their respective mixture proportions. Effects of the above parameters on crack propagation at early ages were investigated on the basis of the authors' crack evaluation criteria.
{"title":"Shrinkage and Crack Propagation of Flowing Concrete at Early Ages","authors":"S. Hiraishi, K. Yokoyama, Y. Kasai","doi":"10.14359/6067","DOIUrl":"https://doi.org/10.14359/6067","url":null,"abstract":"Flowing concrete is a highly flowable and segregation resistant concrete. Shrinkage of the concrete at early ages up to 24 hours under a constant air flow of 8 m/s starting at the age of 2 hours, and crack propagation of the concrete in a restricted form with a thickness of 50 mm have been studied. The experiments were done by controlling the following four mixture parameters: (1) Water-cement ratio: 0.60, 0.45, 0.35, 0.30 and 0.27; (2) Unit amount of water: 185, 175 and 170 kg/cu m; (3) Type of cement: normal, high early strength and belite portland cement; and (4) Type of inorganic admixture: a ground granulated blast furnace slag and a fly ash and their respective mixture proportions. Effects of the above parameters on crack propagation at early ages were investigated on the basis of the authors' crack evaluation criteria.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"50 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":"126602653","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}
Concrete is an essential material for creating infrastructures. However, with the growing awareness of environmental problems in recent years, concrete is now required to function in harmony with nature and help preserve ecosystems. Porous concrete has received a great deal of recent attention. It is believed that porous concrete has water purification functions in flowing water through organism membranes created in a series of inner voids, and that it also creates a new environment for organisms because aquatic organisms and algae adhere to the insides and surface of porous concrete. This paper describes changes over time in the type and number of organisms adhering to porous concrete placed in streams of a river. In addition, the physical properties of porous concrete exposed in a river are discussed. It was concluded that porous concrete can be used as an environmentally-friendly concrete.
{"title":"Porous Concrete for Underwater Organisms in a River","authors":"K. Sakai, K. Shindoh, M. Atohda","doi":"10.14359/6078","DOIUrl":"https://doi.org/10.14359/6078","url":null,"abstract":"Concrete is an essential material for creating infrastructures. However, with the growing awareness of environmental problems in recent years, concrete is now required to function in harmony with nature and help preserve ecosystems. Porous concrete has received a great deal of recent attention. It is believed that porous concrete has water purification functions in flowing water through organism membranes created in a series of inner voids, and that it also creates a new environment for organisms because aquatic organisms and algae adhere to the insides and surface of porous concrete. This paper describes changes over time in the type and number of organisms adhering to porous concrete placed in streams of a river. In addition, the physical properties of porous concrete exposed in a river are discussed. It was concluded that porous concrete can be used as an environmentally-friendly concrete.","PeriodicalId":255305,"journal":{"name":"SP-179: Fourth CANMET/ACI/JCI Conference: Advances in Concrete Technology","volume":"18 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":"126173212","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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