IMPROVING THE ENGINEERING PROPERTIES OF CLAYEY SOIL USING SILICA FUME AND SISAL FIBER

Abstract

Building on soft soils continues to be a challenge for civil engineers in the modern world, despite the rapid development of infrastructure projects and advancements in construction technology. They exhibit a large volumetric change upon contact with water, which is the cause of their limited bearing capacity. Various stabilization strategies can be used to handle the soft clay's shear strength issue. In this experiment, sisal fibers and silica fumes were added in different amounts to the clay soil in order to determine the ideal moisture content and strength parameters for reaching the maximum dry density of the soil. By adjusting the amount of sisal fiber for each amount of silica fume, the Unconfined Compressive Strength (UCS) test has been used to examine the strength of both natural clay and clay modified with silica fume (6%, 12%, 18%) and sisal fibers (0.5%, 1.0%, 1.5%) separately, as well as the combination of all the materials. Using a small compaction device, standard proctor test was used to determine the ideal moisture content and maximum dry density. According to the test results, the maximum dry density falls with increasing silica fume content likewise, the maximum dry density increases with increasing sisal fiber content. The addition of 12% silica fume and 2.0% sisal fiber to the clay sample results in a maximum strength when taking the strength parameter into account. Key Words: Compaction test, CBR, UCS, Silica fume, Sisal Fiber