Vertical bearing capacity of inner-digging prestressed piles

To solve the disadvantages of the traditional construction methods for prestressed pipe piles like squeezing effect and noise and to expend their application, a new construction method, inner-digging method is studied. The static load test and other series field tests on hammer piles and inner-digging piles and are discussed, the vertical compressive properties and rules of load transfer of different kinds of piles are investigated. The test results show that the rules of load transfer of inner-digging pipe piles is the same as those of other kinds of piles. The inner-digging method will reduce the pile side resistance and make it lower than that of hammer-piles, but the post-grouting technology can effectively develop the ultimate bearing capacity. The ultimate bearing capacity of inner-digging piles is close to that of hammer piles, which can meet the requirements of construction and will have a good population and application value in the future.