The Effect of Polypropylene Fibers on the Mechanical Properties of Unstable Sand

Soil reinforcement is one of the techniques of dealing with problematic soils like sandy soils. Use of appropriate materials in soil reinforcement، improves the engineering properties and mechanical principles of soil such as strength، stiffness or elastic coefficient، ductility and bearing capacity. Materials for reinforcement include metal، polymer materials and even plants. The present study investigates the effect of poly propylene fibers (6 and 12 mm in length) with different percentages (% 0. 05، % 0. 1، % 0. 15 and % 0. 25) on shear parameters، density specifications and soil bearing capacity. The obtained results analyzed statistically in a completely randomized design، and their mean comparison organized in statistical level of %1 (P<0. 01). Results show that none of the poly propylene fibers have significant effect on optimum moisture and maximum weight per unit volume of soil adherence. While both lengths of mentioned fiber have a significant increase in angle of internal friction، bearing capacity of soil.