Freezing–thawing behavior of fine-grained soils reinforced with polypropylene fibers

Abstract

A number of studies have been conducted recently to investigate the influence of randomly oriented fibers on some engineering properties of cohesive and cohesionless soils. However, very few studies have been carried out on freezing–thawing behavior of soils reinforced with discrete fiber inclusions. This experimental study was performed to investigate the effect of randomly distributed polypropylene fibers on strength and durability behavior of a fine-grained soil subjected to freezing–thawing cycles. For strength behavior, a series of unconfined compression tests were conducted. Mass losses were also calculated after freezing–thawing cycles as criteria for durability behavior. The content of polypropylene fiber was varied between 0.25% and 2% by dry weight of soil in the tests. The test results for the reinforced specimens were compared with that for the unreinforced sample. It was observed that the mass loss in reinforced soils was almost 50% lower than that in the unreinforced soil. It was also found that the unconfined compressive strength of specimens subjected to freezing–thawing cycles generally increased with an increasing fiber content. On the other hand, the results indicated that the initial stiffness of the stress–strain curves was not affected significantly by the fiber reinforcement in the unconfined compression tests.