特高拱坝防渗帷幕幕体厚度及高压长期压水试验研究

Experimental Research on Thickness of Anti-Seepage Curtain and Long-Term Water Pressure Test Under High Pressure in Ultra-High Arch Dam

锦屏一级水电站为世界第一高双曲拱坝,坝顶高程EL1885m,最大坝高305m,在超高水头压力,对坝体轴线上防渗帷幕灌浆的防渗帷幕体厚度、强度、耐久性及抗疲劳性能指标提出了更高的要求.通过对坝基防渗帷幕进行高压长期压水试验,采用"五点法"反复交变的试验压力模拟大坝蓄水期间的水头压力,对防渗帷幕体进行非常规压水试验检测,并结合帷幕常规质量检查手段和方法,对坝体防渗帷幕在高水压力作用下的稳定性进行综合评价.

Jinping first stage hydropower station is the world's highest double-curved arch dam,with the crest elevation EL1885m and the maximum dam height 305m.At the pressure of ultra-high water head,higher requirements are put forward for the thickness,strength,durability and anti-fatigue performance indexes of the impermeable curtain grouting on the dam axis.Through dam foundation seepage prevention curtain for high pressure water pressure test for a long time,the water head pressure of the dam during the impoundment period is simulated by the"five-point method",and the non-conventional water pressure test of the impermeable curtain body is carried out.Combined with the conventional quality inspection method of the curtain,the stability of the dam's impermeable curtain under high water pressure was evaluated comprehensively.