Author : Shinde Rohit Vijay 1
Date of Publication :4th April 2017
Abstract: In Civil Engineering, it is well known that the packing density of the particles in a concrete mix has great impact on the performance of concrete. High performance concrete (HPC) has become more and more popular in recent years. However, the various required performance attributes of HPC, including strength, workability and durability, often impose paradox requirements on the mix parameters to be adopted, thereby making the concrete mix design a very difficult task. This paper introduces the concept of packing density for increasing the performance of HPC. The concept is based on the belief that the performance of concrete mix can be optimized by maximizing the packing densities of the aggregate particles with manufactured sand (Type VSI) and fine particles. This paper involves the various mix proportions of aggregate particles with manufactured sand and study the behaviour of concrete and other parameters. Mix proportion includes the insertion of manufactured sand from 0% to 50% along with aggregates, thus to get the optimum packing density of the aggregate particles, the optimum packing density was obtained at proportion of 25% coarse aggregates (20mm downsize), 25% coarse aggregates (12.5mm downsize) and 50% manufactured sand. By using the optimum packing density combination in mix design of HPC and study the behaviour of concrete and its performance parameters. Using manufactured sand to fill the voids of coarser aggregates has increased the packing density thus by decreasing void ratio and making the structure dense and stiff. Thus increasing the packing density gives significant results on performance of HPC.
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