Experimental study of drained behavior of drilled shafts during static inclined loading

This report presents the results of an experimental study of the behavior of model drilled-shaft foundations in cohesionless soils under static inclined loading. It offers criteria for evaluating the influence of inclined loading on shaft capacity and displacements, as well as guidelines for drilled-shaft foundation design. Researchers constructed model drilled-shaft foundations in three depth-to-diameter ratios in uniform cohesionless soils ranging from loose to dense. They used seven load inclinations, ranging from axial uplift to axial compression. All of the tests were loaded monotonically to failure and beyond. For convenience, the results were normalized by the test results in axial uplift. Test results showed that the capacity of drilled-shaft foundations is influenced significantly by load inclination. The normalized capacity generally increases with increasing shaft depth and soil density. On the basis of these results, design guidelines were developed to address loading combinations.