动静荷载综合作用下桩土共同作用的机理研究

Research on the Mechanism of Interaction between Piles and Soil Layers Under the Dymamic and Static Loads

轴向荷载作用下桩与上体的相互作用理论日趋成熟．但是，迭加水平荷载作用后，桩土相互作用机理更复杂，研究面临新的课题 工程上断桩、裂桩的现象时有发生．针对这一问题，主要分析了静压桩施工过程中，由于压桩机运行荷载与轴向荷载的共同作用而产生桩体受损的原因，在轴向荷载作用下桩与土体相互作用模型的基础上，考虑了压桩机水平振动荷载的作用，建立了轴向静荷载与水平向动荷载共同作用下桩土相互作用模型，并初步进行了工程实例验证，结果尚令人满意．

The fracture mechanism of engineering piles is one of the important issuess in foundation engineering. Many quantitative studies have been carried out on the interaction of piles and soil layers. In the paper, based on the research of mathematical model of the interaction between piles and soil layers under axial loads, considerations are focused on the horizontal vibration force representing pile-pushing machine while it moves. Then, the mathematical model of interaction between piles and soil layers under the synthetic action of horizontal vibration load from pile - pushing machine and axial loads is established. The application of the model to a certain construction case in Guangzhou city shows that the position of stress concentration in prefabricates pile body is closed to the fractured location of the piles.