基于监测资料反演土坝渗流安全分析

Seepage safety analysis of earth dam based on monitoring data

当大坝运行多年后,测压管监测数据与初始设计中的浸润线存在差异时,可建立数学模型,根据运行过程中的上下游水位等实际边界条件,由实测数据反演出土坝各岩土材料的水力特性,重新复核大坝的渗流安全。本文以观音塘水库大坝为例,通过实测资料进行反演,得出水库大坝下游堆石体的渗透系数在运行多年后有变小趋势,与监测资料反映的结果相符,并在此基础上计算了大坝在设计工况下的渗流稳定。结果表明,该大坝目前仍处于安全稳定状态,今后应继续加强监测和分析。

A mathematical model can be established when there is a difference between the monitoring data of the piezometric pipe and the infiltration line in the initial design after the dam has been in operation for many years. The hydraulic features of all rock and soil materials in the earth dams can be inverted according to measured data according to the actual boundary conditions such as the water level in the upper and lower reaches of the dam during operation, and the dam seepage safety can be rechecked. Guanyintang Dam is adopted as an example in the paper, it is concluded through reversion of measured data that the seepage coefficient of rockfill on the lower reaches of the reservoir dam is decreased after operation for many years, which is consistent with the results reflected in the monitoring data. The seepage stability of the dam under the designed condition is calculated on the basis. The results show that the dam is still in a safe and stable state.