The Effect of Jet Grouting on Enhancing the Lateral Behavior of Piled Raft Foundation in Soft Clay (Numerical Investigation)

Soft clay soils cannot usually support large lateral loads, so clay soils must be improved to increase lateral resistance. The jet grouting method is one of the methods used to improve weak soils. In this paper, a series of 3D finite element studies were conducted using Plaxis 3D software to investigate the lateral behavior of piled rafts in improved soft clay utilizing the jet grouting method. Parametric models were analyzed to explore the influence of the width, depth, and location of the grouted clay on the lateral resistance. Additionally, the effect of vertical loads on the lateral behavior of piled rafts in grouted clay was also investigated. The numerical results indicate that the lateral resistance increases by increasing the dimensions of the jet grouting beneath and around the piled raft. Typical increases in lateral resistance are 11.2%, 65%, 177%, and 35% for applying jet grouting beside the raft, below the raft, below and around the raft, and grouted strips parallel to lateral loads, respectively. It was also found that increasing the depth of grouted clay enhances lateral resistance up to a certain depth, about 6 to 10 times the pile diameter (6 to 10D). In contrast, the improvement ratio is limited beyond 10D. Furthermore, the results demonstrate that the presence of vertical loads has a significant impact on sideward resistance.