A Review on Stabilizing Clayey Soil Using Waste Materials

Abstract

Infrastructural development on unstable clayey soil has resulted to the damage of buildings and roads, the loss of lives, and financial instability in many projects including both vertical and horizontal structures due to the incapability of clayey soil to withstand certain magnitude of loadings. Furthermore, the deposit of materials that are left-over in open areas has also become an environmental challenge for residents in many communities. This review elaborates on the effect of waste materials—SDA (sawdust ash), FA (fly ash), and RHA (rice hush ash)—on the shearing strength of clayey soil as agents for stabilization. The study covers significant books on stabilizing clayey soil with additives as well as high indexed research articles that were published from 1998 to 2023. The findings show that, mixing the ash of sawdust with natural clay soil at the peak values of four (4) percent to seven point five (7.5) percent carries up the UCS (Unconfined Compressive Strength), the MDD (Maximum Dry Density), the CBR (California Bearing Ratio), and lowers the soil’s swelling, Optimum Water Content or OMC and Liquid Limit (LL). Similarly, the mixture of FA and clay soil at the optimum values ranging from 9 to 25%, raises the clayey soil’s UCS, MDD, and CBR while lowering its swelling potential, OMC, and LL. Additionally, the UCS, MDD and CBR increases, and the swelling, OMC, and LL reduce at the optimum value of added rice hush ash ranging from 10 to 20%. Thus, it is established that the addition of sawdust, fly, and rice hush can enhance clayey soil’s engineering properties.