AXIAL EXPERIMENTAL STUDY OF PHC PIPE PILES IN DEEP SOFT SOIL FOUNDATION

摘要

Based on the experimental study of different length's prestressed high strength concrete (PHC) pipe piles subjected to axial load in deep soft soil in Zhuhai free trade zone, the bearing capacity behavior and load transfer mechanism are discussed. Results show that in deep soft soil foundation, the failure mechanism and the feature of Q-S curves are different when the bearing stratum is different, and the super-long PHC pipe piles behave as end-bearing frictional piles. The modulus of compressibility of pile tip's soil affects the exertion of the shaft resistance along the pile. For the different soil and the different depth of the same layer of soil, shaft resistance and pile-soil relative displacement are different. It is also important to consider the strength of the pile besides the bearing capacity and the settlement in the design of the super-long pipe piles. Furthermore, the settlement owing to the compression of pile should be considered in the calculation of the settlement. The experimental study method and analyses provide the guidance for design and further research.