Analysis and Prediction of Heave Behaviour for Treated and Non Treated Expansive Soils

Abstract

Expansive soil is considered a worldwide problem that causes extensive damage to civil engineering structures. The problems with foundations on expansive soils have included heaving, cracking and breakup of pavements, building foundations, slab on grade members, channel and reservoir linings.

This research work aims at studying the effect of soil treatment on heave reduction of expansive silty clay soil at three different cases of initial water contents and dry densities. Two treatment methods of expansive soil were studied by adding sand homogeneously or as a separate top cushion.

Laboratory tests in the form of Atterberg limits, grain size analysis, specific gravity, Free swell, swelling pressure and heave measurements were carried out for natural soil and for three mixtures of soil with sand. Each of the natural compacted soil and the three soil-sand mixtures were prepared at three different water contents. Model experiments were done for only natural compacted soil. The model was designed and constructed for measuring the value of maximum heave. At different percentages of loading area ratios, water content percentages and sand cushion thicknesses, model specimens were prepared. The specimens were also statically compacted by 200 ton Newton compression machine.