The freezing and thawing durability of Norway's first Roller Compacted Concrete (RCC) dam was studied using the Scandinavian slab test (European/CEN test method for freezing and thawing durability) and ASTM C671 freezing dilation test. RCC with W/(C+FA) = 0.53 and FA/(C+FA) = 0.67 had some scaling and severe internal cracking in the wet freezing and thawing exposure of the slab test. The period of freezing and thawing immunity of RCC in the separated absorption and sealed freezing procedure of the dilation test was shorter than that of the conventional facing concrete (FC). Air entraining improved the RCC's freezing and thawing resistance, although not to be as good as that of FC with W/(C+FA) = 0.50 and FA/(C+FA) = 0 and 0.40. The FC had low scaling and no sign of internal cracking in the slab test, and the RCC's period of freezing and thawing immunity was longer than the 120 days of absorption used in the dilation test. The air voids of the RCC were coarser and the protective share of voids (= voids that are not filled by capillary suction but filled by 10 MPa pressure head) was lower than in the FC. Critical degrees of saturation were determined for service life prediction by combining dilation- and degree of saturation measurements.
{"title":"High Volume Fly Ash RCC for Dams: Freezing and Thawing Durability","authors":"S. Jacobsen, O. Lahus","doi":"10.14359/10791","DOIUrl":"https://doi.org/10.14359/10791","url":null,"abstract":"The freezing and thawing durability of Norway's first Roller Compacted Concrete (RCC) dam was studied using the Scandinavian slab test (European/CEN test method for freezing and thawing durability) and ASTM C671 freezing dilation test. RCC with W/(C+FA) = 0.53 and FA/(C+FA) = 0.67 had some scaling and severe internal cracking in the wet freezing and thawing exposure of the slab test. The period of freezing and thawing immunity of RCC in the separated absorption and sealed freezing procedure of the dilation test was shorter than that of the conventional facing concrete (FC). Air entraining improved the RCC's freezing and thawing resistance, although not to be as good as that of FC with W/(C+FA) = 0.50 and FA/(C+FA) = 0 and 0.40. The FC had low scaling and no sign of internal cracking in the slab test, and the RCC's period of freezing and thawing immunity was longer than the 120 days of absorption used in the dilation test. The air voids of the RCC were coarser and the protective share of voids (= voids that are not filled by capillary suction but filled by 10 MPa pressure head) was lower than in the FC. Critical degrees of saturation were determined for service life prediction by combining dilation- and degree of saturation measurements.","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133999847","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}
{"title":"Reducing CU Emission into the Atmosphere-Achievement Experience of Croatian Cement Industry","authors":"K. Popović","doi":"10.14359/10774","DOIUrl":"https://doi.org/10.14359/10774","url":null,"abstract":"","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"538 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124264692","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 utilizes electrical methods to follow the early hydration characteristics of a range of materials activated with calcium hydroxide at room temperature (20 degrees C). The electrical response is measured in terms of the in-phase (i.e. resistance) and quadrature (i.e. capacitance) components of the sample admittance. A number of presentation formalisms are exploited in identifying the stages of hydration and studying reaction kinetics in alkali-activated systems. It is also shown that the electrical response of the material displays a frequency dependence, which is particularly evident in the measure capacitance. The work highlights the applicability of the electrical method as a non-invasive, non-destructive technique in evaluating the reactivity of supplementary materials.
{"title":"Reactivity of lime Activated Pozzolans","authors":"W. McCarter, G. Starrs, T. Chrisp","doi":"10.14359/10796","DOIUrl":"https://doi.org/10.14359/10796","url":null,"abstract":"This paper utilizes electrical methods to follow the early hydration characteristics of a range of materials activated with calcium hydroxide at room temperature (20 degrees C). The electrical response is measured in terms of the in-phase (i.e. resistance) and quadrature (i.e. capacitance) components of the sample admittance. A number of presentation formalisms are exploited in identifying the stages of hydration and studying reaction kinetics in alkali-activated systems. It is also shown that the electrical response of the material displays a frequency dependence, which is particularly evident in the measure capacitance. The work highlights the applicability of the electrical method as a non-invasive, non-destructive technique in evaluating the reactivity of supplementary materials.","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"419 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132490610","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}
R. Filho, B. Americano, Emr Fairbairn, J. Rolim, J. F. Filho
This paper evaluates the potential of crushed waste calcined clay brick as cement replacement material. The crushed waste was characterized physically, chemically and mineralogically through fineness test, density, chemical composition and X-ray analysis and the consumption of calcium hydroxide determined using differential thermal analysis. The influence of the partial replacement of portland cement by calcined clay on the strength development was evaluated until the age of 365 days. The percentage of cement replacement, by weight, ranged from 20 to 42% whereas the water/cement ranged from 0.37 to 0.45. The carbon dioxide emissions associated with portland cement production were determined as well as the emissions that can be avoided replacing portland cement by the calcined-clay brick. The results show that the crushed waste presented a good pozzolanic activity and that the compressive strength of the blended mortars was higher than that observed for the control mixture for all levels of cement replacement. The reductions in carbon dioxide emissions can be achieved if pozzolanic materials such as calcined-clay brick is adequately used as cement replacement.
{"title":"Potential of Crushed Waste Calcined-Clay Brick as a Partial Replacement for Portland Cement","authors":"R. Filho, B. Americano, Emr Fairbairn, J. Rolim, J. F. Filho","doi":"10.14359/10779","DOIUrl":"https://doi.org/10.14359/10779","url":null,"abstract":"This paper evaluates the potential of crushed waste calcined clay brick as cement replacement material. The crushed waste was characterized physically, chemically and mineralogically through fineness test, density, chemical composition and X-ray analysis and the consumption of calcium hydroxide determined using differential thermal analysis. The influence of the partial replacement of portland cement by calcined clay on the strength development was evaluated until the age of 365 days. The percentage of cement replacement, by weight, ranged from 20 to 42% whereas the water/cement ranged from 0.37 to 0.45. The carbon dioxide emissions associated with portland cement production were determined as well as the emissions that can be avoided replacing portland cement by the calcined-clay brick. The results show that the crushed waste presented a good pozzolanic activity and that the compressive strength of the blended mortars was higher than that observed for the control mixture for all levels of cement replacement. The reductions in carbon dioxide emissions can be achieved if pozzolanic materials such as calcined-clay brick is adequately used as cement replacement.","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127277141","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}
Fly ash is increasingly used on a worldwide scale in cement and concrete because of reduced cost, material and energy savings, and improved resistance and durability of the fly ash concrete. One of the drawbacks of (Class F) concrete is its potentially relatively low early strength. Highly reactive pozzolanas such as silica fume and metakaolin can be used to enhance the properties of fly ash concrete. However, silica fume and metakaolin are relatively scarce and expensive. Rice husk is an active pozzolana produced by controlled burning of rice husks, hitherto an agricultural waste. This paper describes the combined use of rice husk ash (RHA) and fly ash in high-performance concrete. The high-performance concrete was based on a gap-graded concrete aggregate with fine sand. Further, a superplasticizer was applied. These ternary blended cement concretes showed greater strength gain than the fly ash concrete.
{"title":"Gap-Graded Concrete Blended with Rice Husk Ash and Fly Ash","authors":"D. Bui, P. Stroeven","doi":"10.14359/10794","DOIUrl":"https://doi.org/10.14359/10794","url":null,"abstract":"Fly ash is increasingly used on a worldwide scale in cement and concrete because of reduced cost, material and energy savings, and improved resistance and durability of the fly ash concrete. One of the drawbacks of (Class F) concrete is its potentially relatively low early strength. Highly reactive pozzolanas such as silica fume and metakaolin can be used to enhance the properties of fly ash concrete. However, silica fume and metakaolin are relatively scarce and expensive. Rice husk is an active pozzolana produced by controlled burning of rice husks, hitherto an agricultural waste. This paper describes the combined use of rice husk ash (RHA) and fly ash in high-performance concrete. The high-performance concrete was based on a gap-graded concrete aggregate with fine sand. Further, a superplasticizer was applied. These ternary blended cement concretes showed greater strength gain than the fly ash concrete.","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123678753","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}
N. J. Coleman, D. C. Johnson, O. Shtepenko, C. Hills
The crushing of reclaimed concrete-based demolition waste in the production of recycled aggregate produces a large volume of fine material which is rich in hydrated cement paste phases, the coarser fraction being predominantly composed of aggregate. It is the coarse fraction which is of use in construction and the fine fraction which is destined for landfill. Heavy metal-bearing wastewater and sludge arise from a number of industrial processes including electroplating, galvanizing, metal finishing and battery production. Treatment procedures for aqueous heavy metal-contaminated waste streams include precipitation, adsorption, ion exchange, membrane filtration and solidification/stabilization using cement or lime-based materials. The removal of heavy metal species from aqueous media by the cement-rich fraction of ordinary portland cement-based waste concrete is demonstrated herein. Crushed concrete waste in the particle size range 1 - 2 mm is shown to be effective in the exclusion of a range of heavy metal nitrates from solution. The leaching characteristics of the metal-impregnated cement matrices are also reported.
{"title":"The Stabalization of Aqueous Heavy Metal Species Using Recycled Concrete Fines","authors":"N. J. Coleman, D. C. Johnson, O. Shtepenko, C. Hills","doi":"10.14359/10783","DOIUrl":"https://doi.org/10.14359/10783","url":null,"abstract":"The crushing of reclaimed concrete-based demolition waste in the production of recycled aggregate produces a large volume of fine material which is rich in hydrated cement paste phases, the coarser fraction being predominantly composed of aggregate. It is the coarse fraction which is of use in construction and the fine fraction which is destined for landfill. Heavy metal-bearing wastewater and sludge arise from a number of industrial processes including electroplating, galvanizing, metal finishing and battery production. Treatment procedures for aqueous heavy metal-contaminated waste streams include precipitation, adsorption, ion exchange, membrane filtration and solidification/stabilization using cement or lime-based materials. The removal of heavy metal species from aqueous media by the cement-rich fraction of ordinary portland cement-based waste concrete is demonstrated herein. Crushed concrete waste in the particle size range 1 - 2 mm is shown to be effective in the exclusion of a range of heavy metal nitrates from solution. The leaching characteristics of the metal-impregnated cement matrices are also reported.","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116946417","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}
Cement manufactured from incinerator ash has been developed in Japan. This cement contains 15-20% of C3A and 0.02-0.1% of chlorine. Since the chlorine content of this cement is higher than that of normal portland cement in Japan, there is a concern whether steel bars embedded in concrete using this cement would become rapidly corroded. In this study, the behavior of chlorine in cement hydrates is investigated in terms of the contents of chlorine accommodated by Friedel's salt. The compositions of pore solution in cement hydrates at early ages and the water-soluble and acid-soluble compositions of cement hydrates are analyzed. As a result, it is found that the concentration of chloride ion in pore solution of cement hydrates using cement manufactured from municipal wastes is not too high. It means that many chloride ions could be accommodated by Friedel's salt because of high C3A content.
{"title":"Behavior of Chlorine in Cement Manufactured from Municipal Wastes","authors":"K. Kawai, E. Tazawa, S. Tanaka, S. Yokoyama","doi":"10.14359/10789","DOIUrl":"https://doi.org/10.14359/10789","url":null,"abstract":"Cement manufactured from incinerator ash has been developed in Japan. This cement contains 15-20% of C3A and 0.02-0.1% of chlorine. Since the chlorine content of this cement is higher than that of normal portland cement in Japan, there is a concern whether steel bars embedded in concrete using this cement would become rapidly corroded. In this study, the behavior of chlorine in cement hydrates is investigated in terms of the contents of chlorine accommodated by Friedel's salt. The compositions of pore solution in cement hydrates at early ages and the water-soluble and acid-soluble compositions of cement hydrates are analyzed. As a result, it is found that the concentration of chloride ion in pore solution of cement hydrates using cement manufactured from municipal wastes is not too high. It means that many chloride ions could be accommodated by Friedel's salt because of high C3A content.","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124680964","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}
For the practical use of granulated blast-furnace slag as a clinker substitute, the addition of an activator is necessary, in order to ensure that a sufficient early and ultimate strength will be reached. Up to now, portland cement has been the most common type of activator for granulated blast-furnace slag. The addition of portland cement leads to the activation of the granulated blast-furnace slag either on an alkaline or, to a minor extent, on a sulfate basis. Materials which prevent the obstruction of the latent hydraulic reaction by a close gel layer of reaction products work as an activator. In this paper, the influence of different fine-grained additives, e.g. fly ash or cement kiln dust, on the granulated blast-furnace slag reaction and the strength development is discussed. The investigations showed that it is basically possible to manufacture composite cement with a high content of granulated blast-furnace slag by using industrial by-products. These cements show particularly a higher early strength than the reference cement, dependent on the composition respectively to the addition. The reactivity of the blast-furnace slag is strongly influenced by the chemical composition of the addition or activator but also by the mineralogical and chemical composition of the blast-furnace slag.
{"title":"Influence of Different Secondary Raw Materials on the Granulated Blast-Furnace Slag Reaction","authors":"W. Brameshuber, P. Schroder","doi":"10.14359/10786","DOIUrl":"https://doi.org/10.14359/10786","url":null,"abstract":"For the practical use of granulated blast-furnace slag as a clinker substitute, the addition of an activator is necessary, in order to ensure that a sufficient early and ultimate strength will be reached. Up to now, portland cement has been the most common type of activator for granulated blast-furnace slag. The addition of portland cement leads to the activation of the granulated blast-furnace slag either on an alkaline or, to a minor extent, on a sulfate basis. Materials which prevent the obstruction of the latent hydraulic reaction by a close gel layer of reaction products work as an activator. In this paper, the influence of different fine-grained additives, e.g. fly ash or cement kiln dust, on the granulated blast-furnace slag reaction and the strength development is discussed. The investigations showed that it is basically possible to manufacture composite cement with a high content of granulated blast-furnace slag by using industrial by-products. These cements show particularly a higher early strength than the reference cement, dependent on the composition respectively to the addition. The reactivity of the blast-furnace slag is strongly influenced by the chemical composition of the addition or activator but also by the mineralogical and chemical composition of the blast-furnace slag.","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133398847","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 cement manufacturing technology that utilizes incinerator ash up to 50% of raw materials has been developed. This cement is called Eco-cement. Eco-cement is a new type of Portland cement being developed not only to solve the municipal and industrial waste problem caused by limited availability of landfill sites, but also to contribute to the protection of the environment by providing a complete recycling system of wastes that would otherwise be dumped. There are two types of Eco-cements. One is rapid hardening type that contains about 0.5 to 1.5% of chlorine. The other is normal type that contains relatively low chlorine and shows similar properties to normal Portland cement. In this study, strength development, mechanical properties and drying shrinkage, autogenous shrinkage and crack resistance of concrete made with normal type of Eco-cement was compared with that of concrete made with normal Portland cement and low-heat Portland cement. Drying shrinkage of concrete made with normal type of Eco-cement is not very different from that made with normal Portland and low-heat Portland cements. However, cracking resistance of concrete made with normal type of Eco-cement is remarkably higher than that made with normal Portland and low-heat Portland cements.
{"title":"Mechanical Properties and Shrinkage of Concrete Made with Eco-cement","authors":"S. Tanaka, H. Tanaka, S. Yokoyama","doi":"10.14359/10790","DOIUrl":"https://doi.org/10.14359/10790","url":null,"abstract":"A new cement manufacturing technology that utilizes incinerator ash up to 50% of raw materials has been developed. This cement is called Eco-cement. Eco-cement is a new type of Portland cement being developed not only to solve the municipal and industrial waste problem caused by limited availability of landfill sites, but also to contribute to the protection of the environment by providing a complete recycling system of wastes that would otherwise be dumped. There are two types of Eco-cements. One is rapid hardening type that contains about 0.5 to 1.5% of chlorine. The other is normal type that contains relatively low chlorine and shows similar properties to normal Portland cement. In this study, strength development, mechanical properties and drying shrinkage, autogenous shrinkage and crack resistance of concrete made with normal type of Eco-cement was compared with that of concrete made with normal Portland cement and low-heat Portland cement. Drying shrinkage of concrete made with normal type of Eco-cement is not very different from that made with normal Portland and low-heat Portland cements. However, cracking resistance of concrete made with normal type of Eco-cement is remarkably higher than that made with normal Portland and low-heat Portland cements.","PeriodicalId":106585,"journal":{"name":"SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131184004","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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