锦屏二级电站引水隧洞围岩高压固结灌浆试验

The high-pressure consolidation grouting test for surrounding rock of diversion tunnel of Jinping Ⅱ Hydropower Station

以锦屏二级水电站引水隧洞为例,开展了薄衬砌非完全封闭条件下,围岩高压固结灌浆试验研究。为防止灌浆施工对已衬砌混凝土造成抬动破坏,固结灌浆前,在衬砌上钻设"防抬泄压孔",部分释放集中在混凝土衬砌与基岩接触面上的浆液压力。试验验证了"防抬泄压孔"在高压固结灌浆时可对薄衬砌起保护作用。试验效果表明,试验所采用的工艺可行、效果显著。

The diversion tunnel of Jinping II Hydropower Station was taken as an example to carry out high - pressure consoli- dation grouting test for surrounding rock under the thin and incomplete closed concrete lining. In order to avoid the lifting - fail- ure of the lining concrete caused by grouting pressure, the ＂ pressure relief holes for anti - lifting＂ were drilled on the lining be- fore grouting construction to partly release the slurry pressure at the interface of concrete lining and foundation rock. It was proved that the ＂pressure relief holes for anti -lifting＂ played an important role in protecting thin concrete lining in the high pressure consolidation grouting process, and the process was feasible and effective, which can speed up the construction and save con- struction cost.