张玉洁， 李晓哲， 姜海波， 侍克斌.热-力作用下水工隧洞围岩-支护结构耦合力学特性及相互作用机制Journal of Water Resources and Water Engineering[J].,2022,33(3):191-201
热-力作用下水工隧洞围岩-支护结构耦合力学特性及相互作用机制
Coupling mechanical properties and interaction mechanism of surrounding rock-supporting structure of a hydraulic tunnel under thermal-mechanical action
The interaction between the surrounding rock and supporting structure is an important factor affecting the stability of hydraulic tunnel structure in high altitude cold regions, it is of practical significance to study the temporal and spatial evolution of the interaction between surrounding rock and supporting structure of hydraulic tunnels under thermal-mechanical actions. Based on the field monitoring data of a hydraulic tunnel in a cold region of Xinjiang, the finite element simulation was used to calculate the elastic-plastic solution of the interaction between the surrounding rock and tunnel lining under thermal effect, so as to analyze the spatio-temporal variation characteristics of temperature field and stress field of the tunnel coupling structure under thermal effect. The results show that the low temperature in the tunnel has a great influence on the temperature field and stress field of the coupling structure. The implementation of insulation measures should be conducted to ensure that the temperature along the radial direction of the structure (with in 2.7 m ) is not less than 0 ℃ under extreme weather conditions. In the early stage of ventilation, the temperature stress plays a leading role in the stress change of the coupling structure. After 21 days, the joint coupling effect of lining support reaction, surrounding rock passive support reaction and surrounding rock boundary constraint should be considered. 48 days before the convection, the inner side of the structure was strained, and the maximum tensile stress of 155 kPa occurred in the inner side of the arch waist. After 48 days, the compressive stress of the structure increased rapidly, and the coupling stress increased at the highest rate from 48 to 60 days. With the decrease of the temperature, the tensile stress of arch roof and bottom increased sharply at -1.95 ℃, and then started to decrease slowly at -3.5 ℃. This study reveals the whole dynamic process of surrounding rock-supporting structure interaction under thermal action, which can provide a technical support for the safe construction of tunnels in cold regions.