Effect of Static and Cyclic Loading on Behavior of Fiber Reinforced Sand

Abstract

Foundations are often constructed in various sub soil conditions and subjected to static loads due to various structures supported by the foundation. In some circumstances in addition to static loads the foundations are subjected to dynamic loads like machine loads, seismic loads and moving wheel loads. The static behaviors of foundations are explored in detail but not much work was reported on the cyclic behavior of foundations. In this paper an attempt is made to evaluate the static and cyclic behavior of circular footing resting on sand and clay subgrade by conducting plate bearing and cyclic plate load tests in large model box tests. The load-displacement characteristics were found from static plate bearing tests from which modulus of subgrade reaction was found which is used in pavement design and evaluation. Also from cyclic plate load tests coefficient of elastic uniform compression (C u) was evaluated which is a parameter used in the design of machine foundations. In the present study the plate bearing and cyclic plate load tests are conducted for layered soils such as sand overlain by BC soil. The dynamic response was evaluated in terms C u; it is increased from 0.70x10 6 kN/M 3 for unreinforced sand to 1.41x10 6 kN/M 3 for reinforced sand similarly, for BC soil it is increased from 0.21x10 6 kN/M 3 to 0.56x10 6 kN/M 3 for Stabilized BC soil.