Hydro-mechanical Behavior of Polypropylene Fiber Reinforced Expansive Soils

Abstract

This paper presents a series of laboratory tests and evaluates the effect of polypropylene fiber inclusion on volume change behavior and soil-water characteristics of expansive soils. Specimens were statically compacted at maximum Proctor dry density and optimum moisture content with 0%, 0.5% and 1% polypropylene fiber inclusions by dry weight of the soil, and their volume change behavior was studied through swell-shrinkage and consolidation tests. The soil-water characteristic behavior, which is the most significant aspect of soils, was also obtained by a series of matric suction measurements using filter paper technique. It was concluded that polypropylene fiber inclusion is very effective in reducing the compression and swell indices and swell pressures as well as one-dimensional swell amount in saturated condition. Upon desiccation, shrinkage of reinforced soil reduced considerably, as the shrinkage limit increased by more than 50%. Therefore, fiber reinforcement can effectively reduce swell-shrink movement of expansive soils.