Abstract: Preloading is a common ground improvement method. The soft cohesive soils are improved by the dissipation of excess pore water pressures through the wick drain or sand/stone columns. The numerical analysis is performed on the preloading treatment of a soft ground for the riverside raw material stockyard of Shanghai Meishan Steel Company by using sand column method. The sand column is simplified as sand wall in the numerical model. The soil deformation and the pore water pressure distribution and development are simulated. The results indicate that the installation of the sand/gravel columns is in favorable to the dissipation of pore water pressures. Under loading stage, an obvious soft ground deformation can be found. At the end of each load stage, an approximate of 70% of the ultimate settlement can be achieved. After that, the deformation rate is slow and is approaching to a stable status. It is concluded that a safe operation can be achieved.

Key words: Preloading, Soft grounds, Numerical Simulations