隔河岩水电站引水隧洞出口及厂房高边坡上部为灰岩、下部为页岩，页岩部位的钻孔测斜仪监测表明， 边坡地表位移的方向是朝山里， 而不是呈一般向坡外位移的规律。针对这种反常现象，采用了测斜仪导管管形线分析方法， 找到问题的原因是， 边坡下部位移大， 上部位移小， 且在整理孔口累计位移时， 采用了以孔底为参考点(不动点)的做法所引起。为此， 在选取位移参考点前， 须先作线分析， 然后以位移小的一端作为参考点， 得出的位移方向才是正确的。同时， 对管形线及其分析方法如何解决边坡位移方向问题作了简要介绍。

The top rock of exit of the diversion tunnel for turbines and the slope of Geheyan Hydropower Plant is limestone, and the underlying rock is shale. The monitoring data obtained by bore hole inclinometers arranged at the shale position showed that the direction of displacement of earth surface of slope is always toward the inside of mountain, and it isn't as usual toward the outside of mountain. This abnormal phenomenon once was a puzzling problem. For solving this problem, the method of pipeconfigurationline analysis was employed, and a satisfactory explanation was obtained at last. A brief introduction to the definition of pipe configuration line, the method of pipeconfigurationline analysis and how to use the method for solving the problems of displacement of slope is done.