Bearing Capacity of Eccentrically Loaded Embedded Square Footing on Geogrid Reinforced Sand

Abstract

Although lot many research works have been conducted on shallow foundations, still eccentric loadings under geogrid reinforced sand bed for different overburden depths are manifested very less. In this thesis, a sharp look has been given to the behavior of square footings under different loading conditions. Here, a number of tests have been carried out on square footing ,of dimension, 10cm x 10cm, on reinforced sand bed. The eccentricities of the footing are varied from 0.05B to 0.15B,with an increment of 0.05B. The biaxial geogrid used here is TGB-40, placed in varying number of layers as 0, 2, 3, 4. The embedment depth is also varied as 0.5B to 1.0B (where B is the width of the footing). The distance between the consecutive geogrids is maintained in a constant manner for all the experiments. A relative density of 69% is achieved during all the tests. The Settlement occurred at increasing loading rate is plotted on graphs, from where the load carrying capacity is found out using tangent intersection method. From the limited experiments conducted in the laboratory, an empirical equation has been developed to determine the load carrying capacity of square embedded footing under eccentric load resting over geogrid-reinforced sand by knowing the bearing capacity of the same footing under similar conditions but under centric load. This is achieved by use of reduction factor. Keywords – load carrying capacity, eccentricity, embedment depth, settlement, number of geogrid layers