Utilization of Sustainable Materials for Soil Stabilization: State-of-the-Art

Most of the challenging soil deposits necessitate their stabilization either by adopting mechanical modification, which includes soil replacement, compaction, surcharge loading and piling or chemical alteration by using lime, cement, and chemical additives. These methods of stabilization are oriented towards improving certain defined properties such as plasticity, swell potential, strength, and density of the soil mass. Besides, one of the most crucial challenges that is faced is "stabilization induced cracking of the fine-grained soils," which turns out to be the basic reason for the failure of the soil mass and subsequent failure of the structures. However, concerns such as non-availability of the ideal soil for replacement of the native soil and even inaccessibility of the site and laborious soil-stabilizer mixing methods necessitate exploring suitable alternatives for stabilization of such soil deposits that adds up to the vows of the practicing engineers. A few other pressing issues which need to be addressed are the adverse effects caused by these additives on the environment (viz., release of greenhouse gases and/or subsequent leaching of chemicals into the ground water). In such a scenario, application of industrial by products (viz., fly ash, cement kiln dust, blast furnace slag, rice husk ash, silica fumes, red mud, and textile waste), which could be defined as "sustainable materials," find a special place in the modernday soil stabilization and modification exercise. Keeping this in view, a critical synthesis of the literature has been presented in this paper, which showcases superiority of the sustainable materials over the conventionally used soil stabilizers and the need for conducting further research to make these materials an easy and choicest replacement over the former.