Bearing capacity of cone pile under action of negative friction resistance

Development of special-shaped pile is one of the important measures to reduce the negative friction, the types and characteristics of the current special-shaped pile reducing the negative friction were analyzed and summarized, and the authors introduced a state authorized invention patent——The thread at the end of the X shaped precast pipe pile and its construction method. Distribution of circular section pile and tapered special-shaped pile on the same surface load under the condition of axial force of pile were simulated respectively by FLAC^3D software. Results show that the effect of longitudinal section of tapered settings can effectively reduce the negative friction. The mechanism of the thread at the end of the X shaped precast pipe pile which can significantly reduce the negative friction was elaborated. The theoretical foundation for design and application of research results for the thread at the end of the X shaped precast pipe piles was provided.