高温热害水工隧洞支护结构受力分析数值模拟研究

摘要

为得到高温热害水工隧洞支护结构的受力机理,以新疆某引水隧洞为例,通过理论计算并使用ANSYS建立热-固耦合模型,对高温热害隧洞支护结构的受力特征进行了计算和分析.结果表明:在围岩与混凝土间设置隔热层能显著改善一期混凝土衬砌的受力情况,衬砌平均应力减小约46％,对二期混凝土无明显影响;隔热层会使支护结构的平均位移增大约14％;隔热层能显著提高一、二期混凝土的安全系数,其均值＞1.对隧洞进行喷锚支护并对二期混凝土进行配筋后,隔热层+一期混凝土+二期钢筋混凝土组成的支护结构可以满足工程安全性的要求,可应用于实际工程中.%In order to obtain the stress mechanism of hydraulic tunnel lining under high geothermal condition,we calculated and analyzed the mechanical characteristics of a diversion tunnel in Xinjiang through theoretical calculation and ANSYS within established hot-solid coupling model.Interrelated analyses conclude that heat insulation layer between surrounding rock and concrete could obviously improve the stress situation of the primary concrete lining by reducing the average stress by about 46％,but had no significant effect on the secondary concrete lining;also the average displacement of the lining structure increased about 14％;the thermal insulation layer could also significantly improve the safety factor of primary concrete lining and secondary concrete lining,with the mean value greater than 1.The supporting system together with heat insulation layer,primary concrete lining and secondary reinforced concrete could meet the safety requirements,and can be used in practical engineering.