Numerical Study of Load Distribution in Piled Raft Foundations Under V-H-M Loading
摘要
The piled raft foundation (PRF) system is highly regarded as an efficient foundation choice for high-rise buildings, primarily because it substantially reduces settlement and differential settlement, thereby improving the stability of the building. Extensive research has been conducted on load distribution within the PRF system under static vertical loads. However, the impact of combined vertical, horizontal, and moment (V-H-M) loads on load sharing is often neglected because of the complexities associated with modelling PRF systems. Despite this, it is essential to assess load distribution in PRF under combined vertical and lateral loads, as these foundations commonly experience horizontal loads and moments from various sources. This study investigates the impact of V-H-M loading on the load distribution in PRF. A three-dimensional (3D) numerical analysis is performed on a PRF with a 3 × 3 pile configuration embedded in sand using Finite Element Analysis (FEA). Soil is modelled as a 3D continuum using the Mohr–Coulomb constitutive model, employing critical state-based soil parameters to simulate the elasto-plastic behaviour of sand. The piles are represented using three-dimensional solid elements, and the raft is modelled with plate elements. After successful validation of the proposed numerical model with data obtained from laboratory test, the model was then evaluated under various loading conditions. The study evaluates load distribution under both vertical and V-H-M loading conditions. Finally, design recommendations are provided based on the findings.