Laboratory investigation of the treatment effects by hydraulic binders on the physical and mechanical properties of an overconsolidated expansive clay

This paper presents and analyses a series of laboratory test results of physical and mechanical characterisation obtained on an overconsolidated expansive clay treated by locally manufactured hydraulic binders (composed Portland cement and extinct lime). Test results show that this clay is characterised by physical and mechanical properties sensitive to hydraulic binders, but more with cement than with lime. It can be noted an important reduction of its plasticity which becomes less sensitive to water, resulting in an appreciable mitigation of its potential of swelling. Also, a significant improvement of its bearing capacity and of its drained and undrained shear strength can be noted. It can be concluded that the best performances were obtained for a simple treatment dosage of 8% cement or lime content, and for a mix treatment dosages of 8% cement and 4% of lime contents. This last solution is most advantageous.