大量试桩资料表明,桩身荷载传递函数曲线多符合双曲线模型,故有必要对基桩荷载传递性状进行非线性分析.为此,文章首先讨论了桩侧摩阻力的主要影响因素和计算方法,然后引入双曲线模型,以荷载传递法建立桩身荷载传递基本微分方程.在此基础上,导得了考虑桩土相互作用及土体分层性质的幂级数解答,并将其用于实测试桩资料的数据分析.对比分析结果表明,基于双曲线模型的非线性计算方法能更准确的描述桩身荷载传递性状,且参数易于获取,是一种可行的计算方法.
Many static test data indicate that, the load-transfer curves can be well fitted with hyperbola, so nonlinear analysis on behavior of load transferring along pile shaft is necessary. Therefore, the primary influential factors and calculation methods of side resistant are first discussed in the paper, then, the differential equation is established based upon the hyperbola model by load transfer method.According to tiffs, considering the character of layered stratum and pile-soil interaction, the exact solution is obtained by power series. Lastly, the data of an engineering pile test is analyzed by the method and the result shows that the calculated values of pile-axial force agree well with the measurement. The conclusion can be drawn that, the nonlinear calculation method based on hyperbola model can accurately describe the load transferring process and the calculation parameters can be easily obtained, which is a feasible calculation method in engineering.