Ground Improvement by Granular Anchor Pile Foundation in Cohesive Soil Under Axial Pullout Loads

Due to rapid urbanization and increase of population, the demand of construction has increased significantly during the last few decades and thus resulting in scarcity of land. So, to eradicate this problem, geotechnical engineers are using several ground improvement techniques such as use of geosynthetics, stabilization of soil, vibro-compaction, stone column, blasting, compacting piles and granular anchor pile foundation to construct buildings on weak subsoil strata for the optimum usage of land. These techniques are used to improve the soil bearing capacity to withstand compressive as well as uplift forces imposed on the structure. The adoption of suitable type of foundation technique will depend upon various factors such as nature of soil, type of loading and type of structure. Granular anchor pile foundation is the innovative technique used to sustain the compressive and pullout loads over weak subsoil. In this paper, the laboratory experiments were conducted to understand the behavior of axial pullout load of granular anchor pile foundation in cohesive soil. The parameters studied were length of the pile, diameter of the pile, L/D ratio and size of the granular fill material. The test results indicate that the pullout capacity decreases with the increase in L/D ratio from 7.5 to 12.5. There was an increase in the pullout load resistance, when the diameter of the pile increases. Moreover, pullout load capacity increases when size of the granular fill increased.