Author : Dr. Nagu P.S .Dr. S.Chandrakaran, & Dr. N.Sankar

Influence of randomly oriented discrete nylon fiber reinforcement (0.15mm diameter) on the properties of lime (CaO) treated clayey soil is investigated in the present study. The soil was artificially remoulded by adding lime and different percentages of short discrete nylon fibers with different aspect ratios. Different Laboratory Tests were conducted to examine the influence of nylon fibers on the strength behaviour of the lime stabilized clay. A novel specimen holder was fabricated to test 100mm diameter specimens in the conventional box shear test equipment.  The test results indicated marginal improvement in strength parameters of lime stabilized clayey soil with the nylon fiber reinforcement. The fiber addition significantly imparted the ductility to the soil which changed the mode of failure from brittle to ductile. The brittleness imparted by the lime in the stabilization of clayey soils can be countered by the fiber reinforcement. The results indicated the potential of nylon fiber reinforcement which is different from the proprietary (micro or fibrillated) fibers in improving the quality of lime stabilization of problematic soils like clay especially in reducing the brittleness imparted by lime stabilization, suggesting the usefulness of the technique for countering one of the constraints posed by lime stabilization.

Keywords: Fiber Reinforcement, Lime Stabilization,   Modified Box Shear Test, Subgrade Improvement.