Dynamic Interaction Factors for Floating Pile Groups

Abstract

A comprehensive set of dimensionless graphs of complex‐valued dynamic interaction factors versus frequency is presented for vertical, horizontal, and rocking harmonic excitation at the head of each pile. These readily applicable graphs have been developed with a rigorous analytical‐numerical formulation for two idealized soil profiles (a homogeneous half‐space and a half‐space with modulus proportional to depth) and three pile separation distances (3, 5, and 10 pile‐diamcters). A wide range of values has been parametrically assigned to pile slendcrncss and pile‐to‐soil stiffness ratios. The results are discussed at length to gain valuable insight into the nature of dynamic pile‐soil‐pile interaction. Gcotcchnical and earthquake engineers can use the presented graphs exactly as they use the classical interaction factors for static deformation analysis of pile groups.