白鹤滩水电站坝基岩体盖重固结灌浆研究

Suggestion and result analysis on rock-cover consolidation grouting test of dam foundation under complicated geological conditions

白鹤滩水电站是国内外首个利用柱状节理玄武岩作为基础的特高拱坝。为解决坝基柱状节理玄武岩开挖松弛问题,满足特高拱坝稳定、安全条件,研究提出了河床坝段岩体盖重固结灌浆方案。在左岸坝基高程650-630m开展生产性试验,灌浆后采用声波测试和压水试验,同时探索了保护层小梯段预裂爆破对已灌浆岩体的影响。试验结果表明,该方案对白鹤滩坝基复杂地质条件的处理是可行的,可用于下一步固结灌浆施工。

Baihetan Hydropower Station is the first high arch dam based on columnar joint basalt at home and abroad.In order to solve the problem of relaxation of columnar joint basalt after excavation,and meet the stability and safety conditions of super high arch dam,rock-cover consolidation grouting plan at dam section of riverbed is proposed.And large scale experiment was carried out at 650~630 meters of left dam foundation,proving the effect of rock-cover consolidation grouting and influence on grounted rock mass after protective layer excavation via sonic wave testing and water testing.The experimental expectation of the test was acheved and the feasibility of the plan was verified.Suggestions for strengthening treatment of the shallow rock mass after protective layer excavation.Rock-cover consolidation grouting plan is available for dam section of riverbed of Baihetan Hydropower Station.And the grounting method,the parameter as well as the test results all provide reference significance on consolidation of dam foundation of columnar joint basalt geological super high arch dam.