The effective stress iterative method of estimating neutral point and downdrag on a single pile was presented in this paper.

采有应力迭代算法来确定中性点的位置和计算下拉荷载,并通过一个实例来说迭代试算的过程。

Analysis results show that location of pile neutral point is the lowest and downdrag caused by NSF is maximal if neglecting working load on pile top.

分析结果表，虑桩顶荷载的中性点位置是最低的，下拽力是最大的。