Defects exist in vertical reinforcement

such as drainage capacity and large bearing capacity cannot be achieved at the same time. This study developed a new type of porous pipe pile with drainage function. It is assumed the tube flow for pore fluid

and the continuous pore pressure according to Poiseuille equation. Then

the analytical solution of strain consolidation is deduced. The drainage pile presents the best consolidation capacity compared to sand drain

gravel pile and undrained pile. The effect of pile modulus

mattress modulus and radius ratio on consolidation are also analyzed. Drainage capacity and modulus are two main factors that affect the consolidation performance. The drainage capacity is the most important. Within the same drainage capacity

greater the modulus of the pile produces faster consolidation process.