A numerical and experimental study of bearing stiffness of drilled shafts socketed in heterogeneous rock

The objective of this study is to evaluate the effect of spatial variability of rock elasticity on the tip resistance of drilled shafts using experimental tests, finite element analysis (FEA) and geostatistical principles. A mathematical and computational model for simulating the multi-dimensional soil–structure interaction is developed using the ADINA FEA program and validated using data obtained from laboratory and centrifuge tests. Subsequently, the FEA model is used to quantify the spatial variability effect on the bearing stiffness of the deep foundation. Using geostatistical principles, a relationship is derived between deterministic and probabilistic end bearing stiffnesses of the rock conditions.