Study on effect of vacuum preloading method improving hydraulic filled soft clay

Vacuum preloading is an effective method to improve the soft soil foundation. After vacuum preloading, the bearing capacity of the ground can reach to 80 kPa, which meets the design requirement for most of goods yards, warehouse, low-rise industrial and civil constructions. Vacuum preloading method is widely used to improve hydraulic filled soft clay in Tianjin Port. During vacuum preloading, the ground settlement along the depth, the lateral deformation of the area boundary and the pore water pressure in the soil are all necessary reference parameters to control construction procedure. Carrying out vane tests before and after vacuum preloading is another important measure to evaluate the improvement effect of vacuum preloading. Based on the practical experience of Tianjin Port, the monitoring measures and reference parameters which are generally used in the vacuum preloading are concluded. The soil foundation deformation and the effective stress increase during the vacuum preloading are simulated by numerical methodology.