金盆拱坝深厚砂砾石地基处理方法及效果

拱坝对建基面要求相对较高,一般要求建基面开挖至弱风化至新鲜基岩处,而建基面处于非岩石基础上的拱坝则较少。金盆拱坝坝基河床深厚砂砾石基础不能深挖清除,拱坝需直接座于经处理的深厚砂砾石地基上。根据实际地形地质及工程特点,采用多道地下连续墙及高压旋喷桩综合处理的方法对金盆拱坝深厚砂砾石基础进行处理。整体有限元分析结果及试运行期间观测资料均表明,该处理方法安全有效,可为类似工程提供参考。

Treatment Methods and Effects of Deep Gravel Foundation of Jinpen Arch Dam

Arch dams have relatively high requirements on the foundation surface, and generally requires weak weathering to fresh bedrock. At present, there are few arch dams built on non-rock foundation at home and abroad. For Jinpen arch dam, deep excavation is not allowed for the deep gravel foundation of the river bed, and the arch dam should act on the treated deep gravel foundation. According to the actual topographic, geological and engineering characteristics, the method of comprehensive treatment of multi-channel concrete diaphragm wall and high-pressure jet grouting pile is adopted to treat the deep gravel foundation of Jinpen arch dam. The results of finite element analysis and observation data during trial operation show that the modified method is safe and effective, and can be used as a reference for similar projects.