Natural Rubber Latex for Improving Ductility Characteristics of Soil: A Preliminary Experimental Investigation

A novel concept of applying natural rubber latex (NRL) to improve the ductility characteristics of soil is addressed in this paper. A preliminary study has been conducted by analysing the load-deformation behaviour of three soils with different plasticity characteristics by performing unconfined compression strength tests. Various quantities of NRL, in liquid form, were admixed with dry soil keeping the water content of soil-NRL mix less than the optimum moisture content of that soil. Three parameters viz. deformability index, energy absorption index and brittleness index have been evaluated to quantify the ductility enhancement in NRL-treated soil. An appreciable increase has been observed in the deformability index and energy absorption index of NRL-treated soil. The brittleness index has decreased with an increase in NRL content. In addition to the ductility enhancement, even if not so significant, NRL induced an overall strength improvement of soil. The load-deformation behaviour of NRL-treated soil was compared with that of cement stabilised soil. NRL treatment results in lower strength and substantially higher ductility than cement treatment. Introductory studies on volume change characteristics, resilient modulus (M-r) and damping characteristics of NRL-treated soils are also presented. From the experiment results, it is recommended that NRL-treated soil can be used for ductility improvement and energy absorption. At the same time, as NRL causes a reduction in elastic modulus, it should be used in combination with any other soil strengthening admixture in scenarios where the strength of soil is a major concern.