The process of vacuum preloading method is to lay a sealing membrane on the surface of the foundation, and use vacuum equipment to evacuate, creating negative pressure in the sand cushion layer under the sealing membrane and in the vertical drainage channel of the soil, creating a pressure difference between the soil and the drainage channel and cushion layer. Under this pressure difference, the pore water in the soil is continuously discharged through the drainage channel, and the pore water pressure decreases, the effective stress increases, and the pore water is accelerated to discharge, thereby consolidating and improving the strength of the soil. This is a soft soil foundation reinforcement method, which ultimately achieves the goal of reinforcing the foundation. Suitable for reinforcing foundations in areas with silt, silty soil, and other soft clay that can be drained and consolidated, and can form negative excess hydrostatic pressure boundary conditions.