Supporting structures are widely used in the foundation pit construction of railways, highways, water conservancy projects, and other types of infrastructure. A significant effect of spatial variability in soil parameters on retaining wall behavior has been reported in many studies. However, relatively little research has been conducted on composite systems consisting of retaining walls and struts. This work primarily investigates how soil spatial variability influences the stability of composite structures composed of retaining walls and struts. First, COMSOL Multiphysics is used to establish a supported excavation model, simulating the interaction between the wall-soil support system. Second, the Karhunen–Loève (KL) expansion is used to capture the variation in the internal friction angle in sandy soil and construct the random field. Then, the random field is exported to COMSOL Multiphysics. Probabilistic analysis of the wall deflection and strut force is performed using the Monte Carlo method. According to the results, spatial variability associated with the internal friction angle of soil significantly affects strut force, wall deflection, and probability of failure in composite structures. Probabilistic analysis indicates that as spatial variability increases, the mean values of maximum wall deflection and strut force can vary by up to 6%.
(423471) et al. (Sun,) studied this question.