Effect of coupling excess pore pressure and soil deformation on nonlinear SSI in liquefiable soil deposits

Abstract

The current seismic design philosophy is based on nonlinear behavior of structures where the foundation soil is often simplified by a modification of the input acceleration depending on the expected site effects. The latter are generally limited to depend on the shear-wave velocity profile or a classification of the site. Findings presented in this work illustrate the importance of accounting for both soil nonlinearity due to seismic liquefaction and for soilstructure interaction when dealing with liquefiable soil deposits. This paper concerns the assessment of the effect of excess pore pressure (#) and deformation for the nonlinear response of liquefiable soils on the structure's performance. For this purpose a coupled # and soil deformation (CPD) analysis is used to represent the soil behavior. A mechanical-equivalent fully drained decoupled (DPD) analysis is also performed. The differences between the analyses on different engineering demand parameters are evaluated. The results allow to identify and to quantify the differences between the analyses. Thus, it is possible to establish the situations for which the fully drained analysis might tend to overestimate or underestimate the structure's demand.

Microstructural Transformations and Prediction Models of an Expansive Soil Subjected to Simulated Rainfall Conditions

“…Changes in pore structure are considered a fundamental factor influencing the macroscopic mechanical properties of soils [15,16]. Skvortsova et al [17] contend that under external environmental influences, soil structure is complex and dynamic, making the geometry of the pore space a crucial indicator of the soil's structural state.…”

Effect of Soil Classification on Seismic Behavior of SMFs considering Soil‐Structure Interaction and Near‐Field Earthquakes

“…e first limitation has to do with the soil-structure interaction (SSI) phenomenon, which is disregarded by several seismic codes along with the regular everyday structural practice, presuming that lack of this phenomenon causes conservative outcomes [2][3][4][5][6]. In the related articles, several investigations approve the great impacts of SSI [7][8][9][10][11]. In this way, observations and examinations from real samples and also analyses have demonstrated that structures based on flexible soil display importantly other seismic responses than that of structures setup on solid rock caused by the substitution of the dynamic features of the system.…”