Experiments on the piping behavior of geofiber-reinforced soil

ABSTRACT: The objective of this paper is, through laboratory experiments, to examine the effect of discrete and randomly distributed fibers on the piping behavior of soil. A silty sand type of soil having 20% fines was selected in the present study. Two types of geofiber, polypropylene and polyester, were used. In this work, various experiments were carried out to determine the influence of geofibers with various dosages and lengths on the seepage velocity and piping resistance of soil. A fiber dosage up to 0.15% only was adopted. It was observed that geofibers increased the critical hydraulic gradient and caused a significant delay in piping phenomena. The observed piping behavior of soil with and without geofibers was verified by conducting constant-load tests in the laboratory. Based on the analysis and interpretation of these experiments, the mechanism of discrete fiber reinforcement in restraining piping of soil is explained.