针对黏性土层的水库浸没评价公式改进

Formula revision of reservoir immersion evaluation for cohesive-soil layer

在平原、阶地地区修建低水头径流式电站,浸没问题是主要的工程地质问题之一。对水库浸没评价,传统的方法是按《水利水电工程地质勘察规范》进行,其中的地下水位壅高值一般按《水利水电工程地质手册》提供的公式来计算。在实际工作中,对砂性土地层,按手册预测的浸没面积与工程实际较吻合,但对黏性土地区,则其预测的浸没面积普遍偏大。在分析现行评价方法的基础上,指出手册给出的预测方法不适用于黏性土库区的原因,论证了采用承压水模式来计算黏性土饱和含水带厚度的可行性。

Reservoir immersion for run - off river hydropower stations, constructed at plain and terrace area, is the main geo- logical problem during construction. Generally, the evaluation on reservoir immersion should be conducted based on the geolog- ical exploring specification, during which the calculation for groundwater rising level is based on the engineering geological manu- al. For sandy -soil layer, the predicted immersion area calculated by groundwater rising formulas in the geological manual, is basically consistent with the measured value, but the prediction result is almost larger than the realistic value for cohesive - soil layer. We point out the causes of errors＇generation for cohesive - soil through studying all the immersion evaluation ways both at home and abroad. The feasibility of calculating width of saturation zone of cohesive - soil by confined water mode is discussed.