Reliability-based analysis and design of obliquely loaded footings

International audienceThis paper presents a reliability-based approach for the analysis and design of a shallow strip footing subjected to an inclined load. The deterministic model used is based on the upper-bound method of limit analysis. Both the punching and sliding modes of failure are considered. The random variables used in the analysis are the soil shear strength parameters and the vertical and horizontal components of the footing load. The reliability index of each mode and the system failure probability were calculated. It was shown that for small values of the vertical component of the footing load, the sliding mode is dominant. When this vertical component increases, the punching mode becomes more critical. The hypothesis of uncorrelated shear strength parameters was found to be conservative in comparison to the one of negatively correlated variables. The coefficients of variation of only the angle of internal friction and the horizontal footing load have a significant effect on the system failure probability. For design, an iterative procedure is performed to determine the breadth of the footing for a target failure probability