The prestressed high strength concrete pipe pile (hereinafter referred to as PHC pipe pile) has been widely used in coastal areas such as Guangdong and Yangtze River Delta because of its high pile strength, fast production speed, stable quality and easy construction control. According to incomplete statistics, only the 2006 Shanghai PHC pipe pile use has more than 28 million meters, accounting for about 80% of the total amount of all prefabricated piles. With the application of PHC pipe piles in Shanghai extensive and in-depth, more and more designers use PHC pipe pile as an uplift pile to use.
PHC pipe pile as an uplift pile with other pile has an unparalleled advantage, especially in the effective pre-stress range of the pile body will not appear cracks, the prestressed steel bar protection is better, can play a better pile Strength, improve the pile bearing capacity. Compared with the conventional piles of concrete piles in the Shanghai area – concrete prefabricated piles or bored piles, the PHC pipe piles can not enhance the tensile strength of the piles because of the need to consider reinforcement due to strict crack control  PHC pipe pile as an uplift pile used in the economy increasingly prominent.
However, due to the design of the PHC pipe pile for the use of piles of different understanding of the PHC pipe pile in the pull design has produced a lot of problems. On the one hand, the tensile strength of PHC pipe pile is too small, leading to the determination of single pile vertical pull bearing capacity is far lower than the pile can provide a single pile bearing capacity; The pull-out design of the pipe pile also neglects the checking of the strength of the pile connecting member. Generally, the simple pile-soil interaction is calculated. The individual project also has a quality accident. This to some extent hindered the PHC pipe pile to further promote and use, serious impact on the basic engineering safety.