Bearing Capacity of Skirted Ring Footing on Dense Sand Overlying Loose Sand

Abstract

Introduction: The ultimate bearing capacity of an unskirted/skirted ring foundation on dense sand overlying loose sand is estimated using finite element analysis in this study. Method: The range of thickness ratio (thickness of top dense sand layer divided by external diameter of ring) was kept between 0.25 and 1.5. The friction angle of the upper dense and bottom loose sand layers was maintained between 40° and 44° and 30° and 34°, respectively. In the case of skirted ring footing, the skirts are attached at the inner edge, outer edge, and both the edges, respectively. Result: According to the results, the bearing capacity increases with an increase in either the friction angle of upper dense and lower loose sand layers or the thickness ratio. A double-skirted ring footing was observed to provide the greatest bearing capacity, followed by footing with skirts attached at the outer and inner edges, respectively. Conclusion: To sum up, the bearing capacity of the ring footing was higher than the circular footing for the given friction angle of the top and bottom layer and thickness ratio.