Sustainable Binders Stabilizing Dispersive Clay

AbstractDispersive clays are characterized by deflocculation in the presence of relatively pure and still water, which can lead to erosion, piping, and other earth instability problems. These can be addressed by stabilization with calcium-based materials (e.g., lime), which are nonetheless environmentally harmful, sometimes inefficient, and cannot guarantee the requested performance. Thus, this technical note intends to examine the performance of a dispersive clay amended with two residues: grounded glass powder (from glass waste recipients), and carbide lime (a by-product of the acetylene gas production). The present study is innovative in that it considers the stabilization of a dispersive soil using these sustainable binders. More specifically, it assesses the effect of the following controllable factors in the strength, stiffness, and more importantly durability of compacted dispersive clay-binder blends: ground glass and lime contents, dry unit weight, curing temperature, and molding moisture content. The statistical analysis of the results has shown that curing temperature was the most influential factor regarding strength and stiffness responses, followed by dry unit weight. Regarding the durability results, the dry unit weight and the amount of carbide lime were the most impacting variables. Likewise, such results could be successfully correlated to the adjusted porosity/lime index, thus yielding a series of equations to predict the blends behavior with great coefficients of determination (R2).