STABILIZATION OF EXPANSIVE SOILS – EVALUATION OF THE BEHAVIOUR WITH LIME

In geotechnical engineering practice the soils at a given site are often less than ideal for the intended purpose. It would seem reasonable in such instances to simply relocate the structure or facility. However, considerations other than geotechnical aspects often govern the location of a structure, and the engineer is forced to design for the site at hand. One possibility is to adapt the foundation to the geotechnical conditions at the site. Another possibility is to try to stabilize or improve the engineering properties of the soils at the site. Depending on the circumstances, this second approach may be the most economical solution for the problem. Stabilization is usually mechanical or chemical, but even thermal and electrical stabilization have occasionally been used or considered [7]. One method to improve expansive soils is chemical stabilization. Chemical stabilization includes the mixing or injecting of chemical substances into the soil. Portland cement, lime, asphalt, calcium chloride, sodium chloride, and paper mill wastes are common chemical stabilization agents. The effectiveness of these additives depends on the soil conditions, stabilizer properties, and type of construction (i.e., houses, roads, etc.). The selection of a particular additive depends on costs, benefits, availability, and practicality of its application.