东西关水电站闸坝及厂房基础开挖

东西关水电站闸坝及厂房基础开挖施工工期短，强度高，难度大，特别是工程建基面是泥质砂岩和砂质粘土岩层上，因此对施工组织设计，钻爆工艺选择，开挖后对建基岩石的保护等提出了很高的要求，针对施工特点，采取“主攻闸坝，拼抢厂房，全面完成施工”的原则进行施工组织；并在施工中采取预裂爆破，深孔微差爆破，柔性垫层爆破等工艺，保证了施工的顺利进行，取得了较显著的成果。

Foundation excavation of dam and Powerhouse in Dongxiguan Hydropower Station

The excavation of dam and powerhouse foundations in Dongxiguan Hydropower Station is characterized by short period, high strength and difficulty, particularly for the structure foundations which lie on the layers of theargillaceous sandstone and arenaceous clay rock. Therefore, high requirement is made in the design of constructionorganization, the selection of drill blasting techniques, the protection of the surface rock in the structure foundationafter the excavation. On the basis of the construction features, the principles of "taking the construction of dam asthe key work, quickening the power house desperately and then completing the all construction works" have beentaken in the construction organization. Meanwhile, under the construction of the Station, the techniques of presplitblasting, deep hole millisecond blasting and soft cushion blasting have been used to guarantee the smooth construction and the outstanding achievements have been obtained.