development of bearing capacity equation for rectangular footing under inclined loading on layered sand

This study provides an equation of bearing capacity for a rectangular footing placed on dense sand overlying loose sand and subjected to inclined concentric loading using the limit equilibrium followed by projected area method. the parameters varied were thickness ratio (0.00 to 2.00) of the upper dense sand layer, embedment ratio (0 to 2), friction angle of upper dense (41° to 46°) sand and lower loose (31° to 36°) sand layer, and applied load inclination (0° to 30°) for the parametric study. the highest and lowest increase in the bearing capacity were observed for a friction angle combination of 46°-36° and 41°-31°, respectively, at different thickness ratios. the bearing capacity obtained from the proposed equation was approximately 4.97 and 10.5 times its initial value at embedment ratios of 1 and 2, respectively. bearing capacity was reduced by 20.55%, 54.58% and 87.90% for load inclinations of 5°, 15°, and 30° for friction angles of upper dense and lower loose sand layer combinations of 46° and 36° and at a thickness ratio of 2. the bearing capacity obtained from the proposed equation decreased by 99.89%, 66.04%, and 61.5% as the load inclination increased from 0° to 30° for embedment ratios of 0, 1, and 2. with respect to finite element results, the average deviation of the bearing capacity obtained from the proposed equation at embedment ratios 0, 1, and 2 was 14.56%, 18.71% and 23.56%, respectively. the proposed bearing capacity equation produced results that were consistent with those reported in the literature, with an average deviation of 10.71% .