Abstract:  Gypsum rock is found in the power house foundation of Jianzishan navigation and hydropower project on Minjiang river during investigation and construction, mainly consisting of slightly weathered to fresh calcareous mudstone interbedded with gypsum. The construction process would destroy the origi ⁃ nal closed hydrogeological environment, and the gypsum is easily soluble in water. The dissolution of gypsum rock is harmful to the structure and foundation, so corresponding engineering measures should be taken. This study introduces the distribution and the physical and mechanical properties of the gyp ⁃ sum rock, assesses impacts of the dissolution of gypsum rock on the dam foundation stability and struc ⁃ tural safety of power house and proposes treatment measures.

Key words:  , gypsum rock, dissolution, seepage prevention, foundation treatment

摘要： 岷江干流尖子山航电枢纽工程在勘察及实施过程中发现厂房坝基存在含膏层，主要为微风化至新鲜钙质 泥岩夹石膏。工程建设过程会破坏原有封闭的水文地质环境，而石膏属于易溶盐，含膏层的溶蚀对建筑物本身结 构及基础危害较大，需采取相应的工程措施。本研究介绍了含膏层的分布情况和物理力学性质，分析了石膏溶蚀 后对坝基稳定性和厂房结构安全性的影响，并提出了相应的处理措施。

关键词: 含膏层, 溶蚀, 防渗, 基础处理