高水头水工隧洞钢筋混凝土衬砌承载特性分析

An Analysis of the Bearing Behavior of Reinforced Concrete Lining in High Head Hydraulic Tunnel

针对高压水工隧洞普遍采用的透水衬砌设计原则,总结了钢筋混凝土衬砌不同阶段的承载行为和损伤演化,模型能够描述损伤开裂后钢筋与混凝土之间的黏结滑移行为,通过耦合计算的方式分析了内水压力增加过程中水工隧洞衬砌的损伤演化过程及渗流场和围岩破坏区的分布形式。结果表明,考虑损伤开裂后部分内水压力由衬砌转为围岩承担,导致围岩破坏范围增大;考虑黏结滑移的刚化效应,开裂后的衬砌更不容易产生新的裂缝,符合水工隧洞的实际规律。

Based on the permeable lining design principle commonly used in high-pressure hydraulic tunnels,the bearing performance and damage behavior of reinforced concrete lining in different stages are summarized.The model can describe the bond slip between steel and concrete after damage cracking.The damage evolution process of the hydraulic tunnel lining and the distribution pattern of the seepage field and the surrounding rock failure zones are analyzed by using the coupling calculation method.The results show that after the damage cracking part of the water pressure is transferred from the lining to the surrounding rock,which leads to the increase in the surrounding rock damage range.Considering the stiffening effect of the bond slip,the cracked lining is less prone to new cracks,in line with the actual law of the hydraulic tunnel.