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Dynamic Stiffness and Seismic Response of Pile Groups.
Kaynia, A. M.; Kausel, E.
National Science Foundation, Washington, DC., January 1982, 131 p.
Identifying Number(s)
A formulation for the analysis of pile groups in layered semi-infinite media is presented. The formulation is based on the introduction of a soil flexibility matrix as well as on dynamic stiffness and flexibility matrices of the piles to relate the discretized uniform forces to the corresponding displacements at the pile-soil interface. Pile group analyses revealed that behavior is highly frequency dependent as the result of wave interferences occurring between the various piles in the group. Large values for stiffnesses as well as large magnification factors for the groups essentially follow the low frequency components of the ground motion. The rotational component is negligible for typical dimensions of the foundation.
Dynamic response; Ground motion; Earthquake engineering; Pile structures; Earthquake resistant structures; Pile soil interactions; Soil properties; Pile foundations; Stiffness methods; Dynamic structural analysis