地铁隧道围岩的热危害越来越明显,其中围岩中的传热起着至关重要的作用。由于埋深浅,在地面大气周期性温度波动和隧道风周期性温度变化的双重作用下，地铁隧道会遇到更复杂的热交换，但是这个问题还没有得到充分解决。在这项工作中,建立了基于双周期温度边界的隧道围岩瞬态传热模型。开发了求解器来估算围岩的温升和传热。然后通过与先前的经验值和半经验方程的比较，验证了该模型的正确性。结果表明,不同深度的围岩温度仍随简谐波波动,有一些地区受到重复效应的严重影响，例如隧道的上覆地层。围岩一般表现为年循环蓄热,但是总储热量逐年减少，直到趋于稳定。此外，隧道越埋越浅，地温的影响越大,隧道围岩温升越高。该研究为确定隧道围岩的储热量和评价地铁热灾害表现过程提供了一种替代方法。
Thermal hazards of the surrounding rock of subway tunnels are becoming apparent, in which the heat transfer in the surrounding rock plays a crucial role. Due to the shallow buried depth, the subway tunnel encounters a more complicated heat exchange under the duplicate effects of periodic temperature fluctuation of ground atmosphere and periodic temperature variation of tunnel wind, but this issue has not been fully addressed. In this work, a transient heat transfer model of tunnel surrounding rock based on dual periodic temperature boundaries was established. A solver was developed to estimate the temperature rise and heat transfer of surrounding rock. The correctness of this model was then verified by comparing with previous empirical values and semi-empirical equations. The results show that the temperatures of the surrounding rock at different depths still fluctuate following the simple harmonic waves, and there are some regions that are heavily affected by the duplicate effects, such as the overlying strata of the tunnel. The surrounding rock generally exhibits heat storage in annual cycle, but the total heat storage decreases year by year until it tends to stabilize. Furthermore, the shallower the tunnel is buried, the greater the influence of ground temperature and the higher the temperature rise in the tunnel surrounding rock. This research provides an alternative approach to determine the heat storage of tunnel surrounding rock and evaluates the process of thermal disaster manifestation of subway.
