Modeling Dynamics of Laterally Impacted Piles in Gravel Using Erosion Method

Abstract

Understanding the dynamic interaction between piles and the surrounding soil under vehicular impacts is essential for effectively designing and optimizing soil-embedded vehicle barrier systems. The complex behavior of pile–soil systems under impact loading, attributed to the soil’s nonlinear behavior and large deformation experienced by both components, presents significant simulation challenges. Popular computation techniques, such as the updated Lagrangian finite element method (UL-FEM), encounter difficulties in scenarios marked by large soil deformation, e.g., impacts involving rigid piles. While mesh-free particle and discrete element methods offer another option, their computational demands for field-scale pile–soil impact simulations are considerable. We introduce the erosion method to bridge this gap by integrating UL-FEM with an erosion algorithm for simulating large soil deformations during vehicular impacts. Validation against established physical impact tests confirmed the method’s effectiveness for flexible and rigid pile failure mechanisms. Additionally, this method was used to examine the effects of soil mesh density, soil domain sizes, and boundary conditions on the dynamic impact response of pile–soil systems. Our findings provide guidelines for optimal soil domain size, mesh density, and boundary conditions. This investigation sets the stage for improved, computationally efficient techniques for the pile–soil impact problem, leading to better pile designs for vehicular impacts.

A State-of-the-Art Review on Computational Modeling of Dynamic Soil–Structure Interaction in Crash Test Simulations

“…However, soil can more realistically be considered as a continuum in the context of pile-soil impacts. The mesh-based finite element method, a numerical tool extensively referenced in studies [8][9][10][11][12][13]29,30,33,34,[71][72][73][74][75][76], adopts this continuum perspective, offering a more comprehensive representation of soil behavior.…”

“…However, the direct method generally falls short in accurately simulating large soil deformations, such as those encountered in scenarios involving rigid piles [76]. In these cases, where stiff piles embedded in soil are subjected to impact loading, substantial soil deformations occur due to pile rotation through the soil, often resulting in fluid-like soil behavior.…”

“…However, this study did not provide details regarding the selection and determination of input parameters for these soil constitutive models. As outlined in studies [76,77], the jointed rock model is designed to simulate the behavior of jointed and stratified rock layers. This model conceptualizes the rock material as being intact with distinct principal joint directions and stratification.…”

“…The application of the jointed rock model in crash simulations involving pile-soil systems is particularly pertinent in scenarios where the rock mass comprises families of parallel joints without fault gouge filling, and the joint spacing is relatively small compared to the structural dimensions. However, given its specific focus on rock-like materials with As outlined in studies [76,77], the jointed rock model is designed to simulate the behavior of jointed and stratified rock layers. This model conceptualizes the rock material as being intact with distinct principal joint directions and stratification.…”