An experimental investigation on geotechnical properties of a clayey soil stabilised with lime and zeolite in base and subbase courses

Abstract

Zeolite is often exploited to reduce the consumption of lime in the treatment of problematic clays and to help further enhance the soil stabilisation process in pavement base and subbase courses. For the mix design of the proposed pavement materials, 8% lime was first opted, according to pH tests, as the optimum content and its different portions were then replaced by zeolite inclusion. A comprehensive set of Atterberg limits, standard Proctor, unconfined compression and unconsolidated undrained (UU) triaxial tests was performed on lime and zeolite stabilised specimens. Zeolite addition into the mixture increased the maximum dry unit weight and decreased the optimum moisture content. The least plasticity index and the highest unconfined compressive strength were attained at 25% of lime replacement with zeolite, deemed to be the optimum mixing content. Results of UU triaxial tests on the optimum mixtures also confirmed the marked improvement of shear strength parameters.