Effects of Discrete Fibers on the Stress-dilatancy and Micromechanics of Fiber-reinforced Sand

摘要

The stress-dilatancy relationship plays a very important role in understanding of the mechanical behavior of granularrnsoils. Numerous experiments on fiber-reinforced uncemented and cemented granular materials have been carried outrnover the last two decades. However, the effects of fiber, cement, and confining pressures on the stress-dilatancyrnbehavior have seldom been investigated, especially at high confining pressures and at micro level. In this paper, thernstress-dilatancy relations and micromechanics of fiber-reinforced uncemented and cemented sand at a wide range ofrnconfining pressures are investigated. Results obtained from drained triaxial compression tests carried out on sand withrnvarious fiber and cement contents are compared and analyzed. The effects of high confining pressure and fiber contentrnon the stress-dilatancy behavior of cemented sand reinforced with polypropylene fibers are discussed. Scanning ElectronrnMicroscopy analysis of the effects of particle, bond and fiber damage on the stress-dilatancy behavior of the sand isrnpresented.