The use of local materials is an important part of sustainability for the concrete industry. The declining availability of aggregate resources in many areas has the potential to result in the use of alternative aggreg...The use of local materials is an important part of sustainability for the concrete industry. The declining availability of aggregate resources in many areas has the potential to result in the use of alternative aggregates of lower quality, which can require higher cementitious materials contents, or the use of aggregates shipped from greater distance. In some markets, manufactured sands are replacing natural sands, which can adversely impact the rheology of cementitious mixtures. The use of certain chemical admixtures has been found to often minimize the need to increase cement and water contents in order to overcome the loss of workability that can accompany aggregate sources which feature flat, elongated, angular, and rough particles. In this study, a wide range of natural and manufactured sands were characterized for gradation, mineralogy, shape, texture, and cleanliness, and also evaluated for their effect on mortar rheology with and without a VMA （viscosity modifying agent） type chemical admixture. Use of the VMA is shown to mitigate the rheological effect of certain sands, and in some cases can allow for optimizing the mixture to lower paste contents. In the case of PCP （polycarboxylate）-based superplasticizers, attention is drawn to the increased dose required to achieve target workability versus superplasticizers based on NSFC （naphthalene sulfonate condensate） when swellable clays are present in the very fine fraction of certain aggregate sources. The use of sands with higher fines contents are also shown to increase the workability provided the fines are of appropriate quality.展开更多
The author＇s Process of Cold Fusion firstly was announced at the International Conference on Emerging Nuclear Energy Systems in 2007, after that it was presented at the International Conference on Emerging Nuclear En...The author＇s Process of Cold Fusion firstly was announced at the International Conference on Emerging Nuclear Energy Systems in 2007, after that it was presented at the International Conference on Emerging Nuclear Energy Systems in 2009. The product has already been applied since June, 2007. It was developed as a large Module of 300 cm x 40 cm, producing energy at 600 megawatts per hour, with unique waste of about 300 cubic meters of pure drinkable instant water a day. There is also a Portable Module, producing about 1 megawatt per hour, having in waste about 1 cubic meter of pure drinkable instant water a day. The important details： （1） we have the ability to stop the Module at any time; （2） the civil applications of this process is mentioned at the articles, published on the website of the European Scientific Parliament in the year of 2010; （3） the diverse modules became the object of special protocols, signed with a number of countries all over the world.展开更多
文摘The use of local materials is an important part of sustainability for the concrete industry. The declining availability of aggregate resources in many areas has the potential to result in the use of alternative aggregates of lower quality, which can require higher cementitious materials contents, or the use of aggregates shipped from greater distance. In some markets, manufactured sands are replacing natural sands, which can adversely impact the rheology of cementitious mixtures. The use of certain chemical admixtures has been found to often minimize the need to increase cement and water contents in order to overcome the loss of workability that can accompany aggregate sources which feature flat, elongated, angular, and rough particles. In this study, a wide range of natural and manufactured sands were characterized for gradation, mineralogy, shape, texture, and cleanliness, and also evaluated for their effect on mortar rheology with and without a VMA （viscosity modifying agent） type chemical admixture. Use of the VMA is shown to mitigate the rheological effect of certain sands, and in some cases can allow for optimizing the mixture to lower paste contents. In the case of PCP （polycarboxylate）-based superplasticizers, attention is drawn to the increased dose required to achieve target workability versus superplasticizers based on NSFC （naphthalene sulfonate condensate） when swellable clays are present in the very fine fraction of certain aggregate sources. The use of sands with higher fines contents are also shown to increase the workability provided the fines are of appropriate quality.
文摘The author＇s Process of Cold Fusion firstly was announced at the International Conference on Emerging Nuclear Energy Systems in 2007, after that it was presented at the International Conference on Emerging Nuclear Energy Systems in 2009. The product has already been applied since June, 2007. It was developed as a large Module of 300 cm x 40 cm, producing energy at 600 megawatts per hour, with unique waste of about 300 cubic meters of pure drinkable instant water a day. There is also a Portable Module, producing about 1 megawatt per hour, having in waste about 1 cubic meter of pure drinkable instant water a day. The important details： （1） we have the ability to stop the Module at any time; （2） the civil applications of this process is mentioned at the articles, published on the website of the European Scientific Parliament in the year of 2010; （3） the diverse modules became the object of special protocols, signed with a number of countries all over the world.
