The influence of the soil constitutive models on the seismic analysis of pile-supported wharf structures with batter piles in cut-slope rock dike

Abstract

<jats:title>Abstract</jats:title><jats:p>In coastal regions, earthquakes caused severe damage to marine structures. Many researchers have conducted numerical investigations in order to understand the dynamic behavior of these structures. The most frequently used model in numerical calculations of soil is the linear-elastic perfectly plastic model with a Mohr-Coulomb failure criterion (MC model). It is recommended to use this model to represent a first-order approximation of soil behavior. Therefore, it is necessary to accommodate soil constitutive models for the specific geotechnical problems.</jats:p><jats:p>In this paper, three soil constitutive models with different accuracy were applied by using the two-dimensional finite element software PLAXIS to study the behavior of pile-supported wharf embedded in rock dike, under the 1989 Loma Prieta earthquake. These models are: a linear-elastic perfectly plastic model (MC model), an elastoplastic model with isotropic hardening (HS model), and the Hardening Soil model with an extension to the small-strain stiffness (HSS model).</jats:p><jats:p>A typical pile-supported wharf structure with batter piles from the western United States ports was selected to perform the study. The wharf included cut-slope (sliver) rock dike configuration, which is constituted by a thin layer of rockfill overlaid by a slope of loose sand. The foundation soil and the backfill soil behind the wharf were all dense sand. The soil parameters used in the study were calibrated in numerical soil element tests (Oedometer and Triaxial tests).</jats:p><jats:p>The wharf displacement and pore pressure results obtained using models with different accuracy were compared to the numerical results of Heidary-Torkamani et al.<jats:sup>[28]</jats:sup> It was found that the Hardening Soil model with small-strain stiffness (HSS model) gives clearly better results than the MC and HS models.</jats:p><jats:p>Afterwards, the pile displacements in sloping rockfill were analyzed. The displacement time histories of the rock dike at the top and at the toe were also exposed. It can be noted that during the earthquake there was a significant lateral ground displacement at the upper part of the embankment due to the liquefaction of loose sand. This movement caused displacement at the dike top greater than its displacement at the toe. Consequently, the behavior of the wharf was affected and the pile displacements were important, specially the piles closest to the dike top.</jats:p>

Parameter Sensitivity Analysis of the Seismic Response of a Piled Wharf Structure

“…Su et al [17] conducted a refined Three-Dimensional (3D) Finite Element (FE) model, including the refined modeling of free-field boundaries and soil-pile interaction, and the seismic performance of the wharf-ground system was systematically explored. Deghoul et al [18] proposed three soil constitutive models: a linear-elastic perfectly plastic model (MC model), an elastoplastic model with isotropic hardening (HS model), and the Hardening Soil model with an extension to the small-strain stiffness (HSS model) with different accuracy to study the behavior of a pile-supported wharf embedded in a rock dike. Meng et al [19] noted that the peak acceleration, spectral characteristics, and ground vibration input direction significantly affected the seismic demand of each performance index by analyzing the critical dynamic response characteristics of piled wharfs under earthquake action.…”

Parameter Determination Method of Soil Constitutive Model Based on Machine Learning

“…The soil is complex in nature and highly variable and is extremely susceptible to external factors such as environment and weather. It was found that there are 3% of accidents caused by design errors [1,2]. Instead, the soil itself is the cause of accidents in geotechinical engineering.…”