针对现有预应力锚索抗滑桩计算模型及其相应计算理论存在的问题，基于有限差分法的原理，提出了改进的锚索桩计算模型并进行了详细的理论推导。根据实际的施工和受力过程，该模型包括预应力施加和滑坡推力作用两个阶段，通过滑坡推力分布形式的改进和桩锚协调变形方程的修正来真实反映预应力锚索抗滑桩的主动式受力特点。同时利用Matlab编制成相应的计算程序进行算例验证，并同目前普遍采用的计算理论进行对比分析。结果表明，该改进计算方法及其相应的计算程序充分考虑了预应力施加这一锚索桩特有的过程所带来的影响，且在计算中不必将锚索拉力等效为在桩顶处施加的剪力和弯矩。另外还可对桩前滑面以上存在任意厚度滑体和任意复杂地基条件的情况进行合理地设计计算，相对于目前已有的计算理论，该改进方法更加合理、可靠。

To resolve the deficiencies of the calculation model for anti-sliding pile with prestressed anchor cable, an improved model is presented with detailed derivations based on the finite difference theory. According to the actual construction process and loading conditions of pile and anchor cable, the model includes two stages, i.e. applying prestress and landslide thrusting. By improving the distribution of landslide thrust and revising the pile-anchor deformation compatibility equation, the actual active mechanical characteristics of anti-sliding pile with prestressed anchoring cable are properly taken into account. The proposed procedure is implemented into a Matlab code and used to analyze practical examples. The results are compared with those of the conventional theories. It is shown that the influence of prestress application on anchor-pile can be properly taken into account in the proposed procedure and its corresponding code, and it is not necessary to equate the anchor cable tension with the shear force and the bending moment at the top of pile. In addition, it can also be used in the design calculation for the cases that the sliding body with arbitrary thickness above the sliding surface exists in front of the piles and for the arbitrary complex foundations. Compared to the conventional theories, the improved procedure is more reasonable and reliable.