Experimental Investigation of the Effect of Microsilica on the Uniaxial Compressive Strength and Rupture Strain of Fine Sand

Abstract

In many areas, natural soil does not have necessary resistance, some additives such as cement and microsilica are added to increase their resistance. In this research, the effect of microsilica on the strength and physical characteristics of fine sand stabilized with cement in sand samples containing cement and microsilica will be discussed. For this purpose, samples of fine sand with three different ratios of cement (2, 4, and 6 percent of soil weight) and four different ratios of microsilica (0, 0.5, 1, and 1.5 percent of soil weight) were mixed with optimal moisture, after Two curing periods of 1 and 7 days were subjected to compression and uniaxial compressive strength tests. The results of the experiments indicate that with the increase in the amount of cement and microsilica, the optimum moisture content in the density increases, the specific weight of the mixture of sand, cement and microsilica increases by adding these materials up to a certain amount, but after that it begins to decrease. . With increasing processing time, uniaxial compressive strength and rupture strain both increase. With a curing time of 1 day, for a fixed cement ratio, the compressive strength of sand-cement increases with the increase of microsilica up to about 20% of the cement weight, but after that, the resistance ratio decreases.
 With a curing time of 7 days for a constant cement ratio, the compressive strength increases with the increase of microsilica. It is also observed that in both curing times for different cement ratios, with the increase in the amount of microsilica, the relative deformation of the fracture increases.