Building Foundations

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*Earthquakes - From Tectonics to Buildings*

pp. 1-34.

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**181**

requalification

**Chapter 8**

**Abstract**

The Dynamic Behaviour of

Liquefiable Soils: Failure

Mechanisms, Analysis,

*Rohollah Rostami, Slobodan B. Mickovski,* 

*Nicholas Hytiris and Subhamoy Bhattacharya*

response of pile foundation in liquefiable soil are provided.

**Keywords:** liquefaction, dynamic behaviour, pile, failure mechanisms,

**1. Introduction (Characterisation of liquefaction behaviour)**

The liquefaction of loose, saturated sands, particularly cohesionless soils is caused by earthquake shaking or cyclic (monotonically increasing) undrained loading. The early work in liquefaction soil in the laboratory apparently emerged from the experience of the Fukui earthquake in 1948 in Japan [1]. It was regarded as a milestone from researchers since its devastating failures were prevalent following the major earthquakes in Niigata, Japan and Alaska, USA, in 1964 [2–4].

Re-Qualification

Pile Foundations in Seismically

This chapter presents a concise overview of the mechanics of failure, analysis and requalification procedures of pile foundations in liquefiable soils during earthquakes. The aim is to build a strong conceptual and technical interpretation in order to gain insight into the mechanisms governing the failure of structures in liquefaction and specify effective requalification techniques. In this regard, several most common failure mechanisms of piles during seismic liquefaction such as bending (flexural), buckling instability and dynamic failure of the pile are introduced. Furthermore, the dynamic response commentary is provided by critically reviewing experimental investigations carried out using a shaking table and centrifuge modelling procedures. The emphasis is placed on delineating the concept of seismic design loads and important aspects of the dynamic behaviour of piles in liquefiable soils. In this context, using Winkler foundation approach with the proposed p–y curves and finite-element analyses in conjunction with numerical analysis methods, are outlined. Moreover, the feasibility of successful remediation techniques for earthquake resistance is briefly reviewed in light of the pile behaviour and failure. Finally, practical recommendations for achieving enhanced resistance of the seismic
