基于差分法的双排抗滑桩结构内力计算

Internal force calculation of double row anti-slide pile structure based on finite difference method

为研究有连梁双排抗滑桩快速有效的内力计算模型,在对有连梁双排桩进行受力分析的基础上,将有连梁双排抗滑桩结构简化为在桩顶连系梁零弯矩处断开的2根单桩结构,通过对双排桩受力进行叠加得到前后排桩桩顶连梁传递的弯矩与剪力,基于有限差分法建立了有连梁双排抗滑桩受荷段、嵌固段全桩内力计算模型,进而对有连梁双排抗滑桩桩体内力进行了计算。同时,通过大型室内模型试验内力实测结果对所计算结果进行了对比验证。结果表明:(1)模型试验结果与所建计算模型得到的桩顶位移与桩身弯矩值吻合较好,说明简化计算模型具有一定的适用性;(2)二者的后排桩最大弯矩出现位置略有偏差,计算得到的最大弯矩位置更接近实际桩体破坏位置,进一步验证了全桩内力计算模型的可靠性;(3)所建有限差分计算模型避免了将受荷段与嵌固段利用连续条件进行迭代的复杂运算过程,大大提升了计算效率,为实际工程提供了一种快速高效的有连梁双排桩内力计算方法。

To develop an efficient internal force calculation model for double row anti-slide piles with connecting beams,the finite difference method was used to calculate the internal force of all piles at the load section and embedded end of double row piles.The structure of double row anti-slide pile with connecting beam was simplified to two single piles disconnected at the zero bending moment of the connecting beam at the pile top;the bending moments and shear forces at the top of the front and back piles were obtained by superposition of the forces on the double row piles.The structural model tests were carried out to check the effectiveness of the calculation model based on the finite difference method.The results show that the model test results are consistent with the data of pile top displacement and pile body bending moment obtained from the calculation model,indicating that the simplified calculation model is effective.There is a slight deviation between the positions where the maximum bending moment calculation is for the rear pile.The calculated maximum bending moment position is close to the real pile failure position,further proving the reliability of the entire pile internal force calculation model based on the finite difference method.The finite difference calculation model avoids the complex calculation process of iterating the loaded and embedded sections using continuous conditions,and provides a fast and efficient method for calculating the internal forces of double row piles with connecting beams in practical engineering.