Simulation of excess pore pressure and vertical settlement of soil under cyclic loading using abaqus

Abstract

The generation of excess pore pressure and resulting settlement in clay soils subjected to cyclic loading is a critical factor influencing the stability and serviceability of foundations in civil engineering projects. This study investigates the mechanisms of pore pressure accumulation and deformation in clay soils when exposed to repeated loading, such as that from traffic or wave action, focusing on the soil's stress-strain response and long-term settlement characteristics. The research employs a series of laboratory cyclic loading tests on undisturbed and remolded clay samples to simulate real-world loading conditions. Parameters such as loading frequency, amplitude, and duration are systematically varied to assess their impact on pore pressure buildup and soil displacement. Data is analyzed to determine the relationship between excess pore pressure and factors like soil plasticity, water content, and initial stress state. Findings indicate that cyclic loading leads to a progressive accumulation of pore pressure, which reduces the effective stress in the soil, resulting in softening and increased settlement. The rate and extent of settlement are found to depend strongly on the cyclic loading characteristics and the soil’s intrinsic properties, with higher frequency and amplitude leading to greater settlement. The results provide a framework for predicting soil behavior under cyclic loads, aiding in the design of more resilient foundations in soft clay soils. This thesis contributes to the understanding of soil-structure interaction under cyclic loading and offers practical recommendations for engineers in predicting and mitigating settlement in clayey soils, improving the long-term stability and performance of infrastructure.