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

采用有效应力迭代算法来性点的位置和计算拉荷载值,并通过一个实来说明迭代试算的过程。

The diagnosis principle and diagnosability conditions are proposed, and the normal tolerance network test nede voltage interval are given by interval iterative algorithm.

该方法给出了容差情断的原理和可断性条件，并利用区间迭代算法，给出了容差网络无故障情的测试节点电压范围。