高压水工隧洞钢筋混凝土衬砌开裂渗漏研究

 基于弹性损伤理论和等效连续介质渗流理论，提出一种可以在高压水工隧洞衬砌开裂后估算隧洞渗水量的方法。以不同水压力作用下钢筋混凝土衬砌的裂缝宽度变化作为考虑衬砌渗透性变化的主要因素，考虑衬砌裂缝与断层相交的情况和高压固结灌浆作用的影响，对水工隧洞充水、放空阶段的内外水渗漏做出相应探讨。将惠蓄高压隧洞的监测数据和数值模型计算结果进行对比得到，隧洞的渗水量与衬砌裂缝开度及洞周是否存在较显著的渗漏通道存在密切联系。在隧洞洞周没有或尚未形成显著渗漏通道的情况下充水或放空时，计算结果与实际监测结果吻合良好；在衬砌裂缝与断层连通的渗漏通道形成后，计算结果和监测结果则会存在一定的差距。研究结果可为水工隧洞充水期内水外渗和放空期外水内渗渗漏量计算提供一种有效的思路。

RESEARCH ON SEEPAGE OF HIGH PRESSURE HYDRAULIC TUNNEL WHEN REINFORCED CONCRETE LINING CRACKING

Based on the elastic damage theory and seepage theory of equivalent continuum media，a method for evaluating the seepage of high pressure hydraulic tunnel after the lining cracking is presented. Changes in crack width of reinforced concrete under different water pressures are considered as the main factors of permeability changes of the lining. The situations of the internal water exuding from the tunnel when water fills the tunnel and the outer water infiltrating into the tunnel when the tunnel is empty are studied respectively. The influences of consolidation grouting under high pressure and the situation when faults get touch with the lining are considered. The comparison between monitoring data of Huixu tunnel under high pressure and results from numerical calculation shows that the seepage of tunnel has a close relation to the crack width of lining and the existence of remarkable seepage channel nearby the tunnel. If there is no remarkable seepage channel nearby the tunnel，when water fills the tunnel or the tunnel is empty，the monitoring results agree better with the computation results. Otherwise，if the remarkable seepage channel which combines the concrete cracks with faults，the difference between monitoring and computation results will become larger. The research results provide an effective thought for the seepage discharge calculation of water flowing into and flowing out of the tunnel at different periods.