Strength and Deformation Properties of Soils Reinforced With Fibrillated Fibers Available to Purchase

The results of preliminary laboratory tests on a clay and a sand reinforced with randomly distributed fibrillated fibers are presented. The results of compaction, direct shear, unconfined compression and California Bearing Ratio (CBR) tests are described. The influence of test parameters such as normal stress, the amount of reinforcement, specimen size, and moisture content is addressed. The tests show that fibers significantly increase the peak compressive strength of clay and sand. The addition of fiber reinforcement in the sand and clay specimens resulted in substantial increases in the peak friction angle and cohesion values. The increase in strength is a function of fiber content and moisture content. The Mohr-Coulomb failure envelopes for the clay specimens are described by a combination of curvilinear and linear sections. The CBR values for the clay and sand specimens were also significantly improved using fiber reinforcement. This preliminary study suggests that for the soils tested and reinforced with 25 mm long polypropylene fibrillated fibers, the optimum fiber content is approximately 0.3% of the dry unit weight of the soil.