某水库土坝地层渗透系数确定

Determination of Formation Permeability Coefficient of An Earth Dam

从大坝填筑施工过程、土层特性和大坝渗透系数的概念和意义出发,以某水库病险大坝为例,深入分析了室内土工实验和原位渗透实验与实际发生偏差的原因。在此基础上,综合前人经验资料,初步提出渗透系数值,再将其带入有限元模型分析大坝渗流场的分布及其演化趋势。把数值模拟的结果和实测资料进行了对比分析,来验证、调整渗透系数值。采用此方法确定的渗透系数进行加固设计,技术可行,经济合理,得到了业主和审查专家的普遍好评。

Taking the weak dam of a reservoir for example, the paper makes an analysis on the reason of the deviation between the laboratory geotechnical test and the in-situ permeability test based on the study of the construction pro- cess, soil characteristics and the conception of permeability coefficient. On that basis, a preliminary permeability co- efficient is obtained based on the former experiences. Then, the distribution and development trend of dam seepage field are observed by using of the finite element model. Finally, the simulation values and the observed results are compared and analyzed for verifying and adjusting the permeability coefficient. The obtained coefficient by the above method is technical feasible and economical reasonable, which is praised by owner and experts.