Deformation features of high-pressure rotary pile reinforced strata by discrete lattice spring modeling (DLSM)

Tunnel excavation in weak surrounding rock areas is prone to landslide accidents, and the use of high-pressure rotary piles to pre-strengthen the soil in the local area can enhance the strength and bearing capacity of the surrounding rock. Discrete lattice spring model is established with the three-dimensional morphology modeling system of the rotary pile reinforcement. It is used to quantitatively characterize the reinforcement effects of high-pressure rotary piles, to analyze the influence of the reinforcement ratio and reinforcement function. The results show that compared with the deformation of unreinforced stratum, the high-pressure rotary pile can better control the ground surface settlement. The larger the reinforcement ratio is, the better the reinforcement effect of the rotary spray pile is, especially with the increase in reinforcement ratio, the contact between individual piles bites to form a row of piles, which can significantly improve the ability of the formation to resist deformation. Under the same reinforcement situation, the square root type reinforcement function has the best reinforcement effect, the line function has the middle reinforcement effect, and the quadratic type reinforcement function has the worst effect.