Simple approach for including foundation–soil–foundation interaction in the static stiffnesses of multi-element shallow foundations

In common engineering practice, foundation–soil–foundation interaction of shallow foundations is frequently ignored. This presumably for cost/benefit reasons, since computationally demanding finite-element and/or boundary element models are required that purpose, and its effects usually assumed to be negligible. this sense, the present paper provides a simple inexpensive way incorporating through numerically explicit stiffness matrix formulation. The necessary ingredients homogeneous non-homogeneous (shear modulus power-law variation with depth) half-spaces given. proposed approach then applied offshore wind turbines’ multiple suction caisson (tripod tetrapod), where it observed significant. Its range validity also established, valuable ready-to-use closed-form formulas correction factors stiffnesses tripod tetrapod groups derived. methodology applicable as long spacing between somewhat greater than foundation depth.