University of Surrey

Test tubes in the lab Research in the ATI Dance Research

Modal analysis of pile-supported structures during seismic liquefaction

Bhattacharya, S and Lombardi, D (2014) Modal analysis of pile-supported structures during seismic liquefaction Earthquake Engineering and Structural Dynamics, 43 (1). pp. 119-138.

[img] Other
Restricted to Repository staff only

Download (3MB)


The purpose of this paper is to investigate the effects of liquefaction on modal parameters (frequency and damping) of pile-supported structures. Four physical models, consisting of two single piles and two 2 × 2 pile groups, were tested in a shaking table where the soil surrounding the pile liquefied because of seismic shaking. The experimental results showed that the natural frequency of pile-supported structures may decrease considerably owing to the loss of lateral support offered by the soil to the pile. On the other hand, the damping ratio of structure may increase to values in excess of 20%. These findings have important design consequences: (a) for low-period structures, substantial reduction of spectral acceleration is expected; (b) during and after liquefaction, the response of the system may be dictated by the interactions of multiple loadings, that is, horizontal, axial and overturning moment, which were negligible prior to liquefaction; and (c) with the onset of liquefaction due to increased flexibility of pile-supported structure, larger spectral displacement may be expected, which in turn may enhance P-delta effects and consequently amplification of overturning moment. Practical implications for pile design are discussed.

Item Type: Article
Divisions : Surrey research (other units)
Authors : Bhattacharya, S and Lombardi, D
Date : 1 January 2014
DOI : 10.1002/eqe.2336
Depositing User : Symplectic Elements
Date Deposited : 28 Mar 2017 13:49
Last Modified : 24 Jan 2020 12:03

Actions (login required)

View Item View Item


Downloads per month over past year

Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800