STRENGTHENING OF CLAY BY GEOGRID REINFORCED GRANULAR PILE

Abstract

Granular piles are being installed for reinforcing the soft ground over the last few decades. Current methods for calculating the loadcarrying capacity of granular piles still remain essentially based on the behaviour of single pile observed in the laboratory. Most popular analytical and numerical approaches tend to consider only a typical pile and surrounding soil to represent the situation of a group of piles working together. This dissertation deals with the behaviour of a single pile surrounded by soft clay. A limited number of laboratory tests have been conducted in laboratory to study the behaviour of a granular pile, reinforced with geogrid layers, supporting a rigid circular footing. The influence of spacing between geogrid layers and the depth of the bottom most geogrid layer, on the performance of reinforced pile, has been investigated through model tests. Geogrid reinforced granular pile has been found to result in significant increase in load carrying capacity. The bulge diameter has been found to reduce due to the incorporation of geogrid layers as reinforcement. Finite element numerical analyses have also been performed using rocscience, Phase z, Version 6. Comparison of numerical analyses has been carried out with the experimental results. Results from relevant published literatures have also been studied in order to validate the general findings from the present study