Dynamic Behavior of Fibre Reinforced Sand

Abstract

Fibre reinforcement has more or less established itself as a composite civil engineering material having significant effect in improving the static strength characteristics of granular soil like sand. However the dynamic behavior of fibre reinforced sand as far as large scale model tests are concerned is rarely discussed in the literature. The present study illustrates the effect of randomly distributed polypropylene fibrillated fibre reinforcement in modifying the dynamic characteristics of locally available sand (Solani River, Roorkee, India). Block resonance tests (BRT) for low-medium strain levels and Cyclic plate load tests (CPLT) for high strain level have been conducted both on un-reinforced and fiber reinforced sand in the laboratory to study its dynamic characteristics. In BRT, the magnitude of resonant frequency and maximum amplitude of vibration of the test block have been recorded at different excitation levels in vertical mode of vibration at a particular percentage of fiber content, thus establishing the effect of dynamic loading or in turn the effect of strain level. The dynamic response was evaluated in terms of coefficient of elastic uniform compression and damping ratio. Where as, in CPLT, settlement and pressure values have been recorded to calculate coefficient of elastic uniform compression at two different strain levels. It was observed that there was no significant effect of fibre reinforcement on the dynamic behavior of sand contrary to the static loading condition.