Effect of Pile Foundation Grouting in Karst Area Based on 3D Numerical Simulation

To study the grouting effect of the modified expansive grouting material developed according to the actual engineering requirements, the slurry parameters were collected through material performance tests such as compressive strength, and applied in the finite element software Midas GTS NX, and based on the three-dimensional cave model constructed by CATIA. The change of stress and deformation of the soil layer under the pile foundation in different states of the cave and modified slurry filling before and after, and the grouting effect was compared and analyzed by this standard. The study showed that the grouting reinforcement of the cave under the pile foundation can effectively avoid the occurrence of engineering accidents, and the overall strength of the modified grouting material was significantly improved, the deformation settlement and stress were reduced, and the structure was more uniform and dense compared with the ordinary cement slurry, which also proves that the numerical simulation analysis has certain guiding significance to determine the grouting effect of the cave, and provides reference for the design and construction of the project.