Lateral stiffness of hybrid foundations: field investigations and 3D FEM analysis

The paper presents stability problems of horizontally loaded pile–soil interaction in the three-dimensional (3D) state of strain. The results obtained are based on full-scale tests and numerical 3D finite-element method analyses including an evaluation of the interaction between the soil and a pile with a cantilever plate. The research and analyses carried out resulted in a better specification of the current methods calculation for a single pile with cap. An analysis of the 3D pile–soil interaction enabled development of the basis for a more precise determination of the lateral stiffness of a pile with cap in cohesionless soil. A better understanding of the problem is of vital importance for designing bridge abutments, retaining walls founded on single rows of piles, foundations supporting structures, and offshore wind turbines subjected to large lateral loads.