Applied Technology Research For Machine-made Sand Self-Compacting Concrete Prepar-ation Method

Self-compacting concrete (SCC), with high fluidity and good ability of anti-segregation and bleeding, can fill the mold uniformly and densely, only rely on its own gravity without vibrations, and meet the forming requirements of modern concrete with complicated structure and intensive reinforcement. The traditional SCC use natural sand as the fine aggregate, but with the reducing of the natural sand increasingly, and the importance of the resources and environmental protection by the government, the supply of the natural sand has been shrinking, and the quality is getting worse. It has a long history of using machine-made sand to prepare SCC in the foreign countries, and it is being common in China also. With the technological progress of the machine-made sand manufacturing, the quality of machine-made sand is fully capable to meet the requirements of making concrete.Using the machine-made sand to prepare SCC is different from the natural sand, due to the differences of the morphological characteristics, particle size and the size distribution of machine-made sand. It has to take the corresponding technical measures according to the morphological characteristics of machine-made sand, if you want to make the SCC whose working performances meet all the requirements. Based on the morphological characteristics of machine-made sand, the article studied the allocation mechanism of SCC, and analyzed the morphological characteristics of machine-made sand particles, particle size, size distribution, and other physical properties. Taking into account of the technical characteristics of the SCC by machine-made sand, the orthogonal test and the design theory of mix proportion of overall calculation method are adopted to analyze the influence law of the machine-made sand SCC caused by fineness modulus, powder content, mineral admixture content, water-binder ratio, sand ratio. We can get the optimum dosage of the various raw materials, thus we can make the self-compacting concrete by machine-made sand.