Effects of Soil-Pile-Structure Interaction on Seismic Response of Sdof Structures

Abstract eng:
The interaction between soil, foundation and structure during earthquake shaking is a complex phenomenon in which several mechanisms are involved. Soil-structure interaction (SSI) is formed by two main mechanisms: kinematic and inertial interaction, involving wave scattering and impedance problems, respectively. Theoretical studies in the subject abound in the literature and show that the effects of SSI on the earthquake response of structures involve mainly an elongation in fundamental natural period and a change (usually an increase) in damping. Nonetheless, the experimental validations of such studies are still scarce. Such validations can be efficiently investigated with physical scaled model in 1-g or n-g devices. In the present paper the soil-pile-structure interaction (SPSI) is investigated by utilizing a set of data selected from a comprehensive experimental test program carried out using 1-g shaking table tests. The scaled model adopted in the tests comprises a group of five piles embedded in a bi-layer deposit with or without a single-degree-of-freedom oscillator mounted on the piles, with or without a rigid connection (cap) between them. The present work focused on the response of the scaled model when subjected to both harmonic input motions and the strong motion recorded at Tolmezzo Station during the 1976 Friuli (Italy) earthquake. The experimental outcomes are compared with some theoretical formulations from the literature. It is found that: (i) the SPSI effects are, as expected, more evident in the system without a stiff connection between the piles and (ii) the theoretical formulae are not able to predict in an accurate manner the above quantities, due to a variety of factors discussed in the paper.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket