PSEUDO-STATIC ANALYSIS OF PILES IN LIQUEFIABLE SOILS: PARAMETRIC EVALUATION OF LIQUEFIED LAYER PROPERTIES

In this paper, pseudo-static analysis of piles in liquefying soils is applied to a case study of a bridge foundation. The response of piles is separately evaluated for the cyclic phase during the intense shaking and development of liquefaction, and for the subsequent lateral spreading phase. With regard to the considerable uncertainties involved in predicting liquefaction and lateral spreading phenomena the effects of key parameters influencing the pile response are examined through parametric analyses. Particular attention is given to the variation in stiffness and residual strength of the liquefied soil, the magnitude of lateral ground displacement and the magnitude of inertial loads from the superstructure. The results shed light on the relative importance of key parameters for different combination of loads and ground conditions, and allow comparative evaluation between loads on the pile exerted by the crust layer and the liquefied layer.