考虑隧洞充水过程的衬砌裂缝宽度计算

分析压力隧洞实际充水过程中的衬砌工作性态,给出稳定渗流状态下的裂缝宽度方程以及考虑充水过程的衬砌裂缝宽度计算方法,以此大体反映钢筋应力(sσ)和裂缝宽度(2a)的发展史,认为其最大值与充水过程有关,其长期稳定值与过程无关。实例计算表明:稳定渗流、衬砌、围岩分开工作状态下的最大钢筋应力σs′及2a值与不透水衬砌常用公式的计算值相比差别很大,而两者联合工作时差别不大。

Calculation of crack width of linings considering loading procedure of pressure tunnels

Considering the loading procedure of hydraulic pressure tunnels,the variation of working states of concrete linings was analyzed,and the formulas for the crack width under steady flows were proposed.A computational method considering the loading procedure of tunnels was presented.It could roughly reflect the development of the reinforcement stress σs and the crack width 2a.The maximum values were dependent on the loading procedure,and the stable values were independent of the loading procedure.The results of an example indicate that the maximum values of the reinforcement stress σs′ and the crack width 2a under independent working states of linings are much smaller than those of impervious concrete linings calculated by commonly-used formulas.However,the differences are small when the linings and sunoanding rock mass work together.