高地温引水隧洞衬砌结构温度应力现场监测与数值模拟

On-site Monitoring and Numerical Simulation of Lining Thermal Stress of High Ground Temperature Diversion Tunnel

为研究高地温引水隧洞支护结构的受力特性,利用有限元数值模拟对现场监测成果进行了分析论证。结果表明,施工期由于温度差异,最大拉压应力量值均较小,最大拉、压应力分别在0.67、0.45 MPa左右;运行期由于过水温度较低,全断面产生拉应力,最大拉应力在3.5 MPa左右;检修期由于隧洞排水,温度回升,由运行期的拉应力开始逐渐转化为压应力,最大压应力在0.35 MPa左右。

In order to study the stress characteristics of supporting structure of a diversion tunnel under high ground temperature environment, lhe finite element method is used to demonstrate the results of on-site monitoring data. The results show that： （a） during construction period, the maximum tensile and compressive stress are small due to temperature difference, and the maximum tensile stress and compressive stress are about 0. 67 MPa and 0. 45 MPa respectively; （b） during operation period, the tensile stress appears in full section due to lower water temperature and the maximum tensile stress is about 3.5 MPa; （c） during overhaul period, the tensile stress is gradually transformed into compressive stress as the rise of tunnel temperature and the maximum compressive stress is around O. 35 MPa.