高岩温铁路隧道温度应力场耦合研究
发布时间：2018-07-27 09:13
【摘要】：随着西部大开发战略的深入开展，作为交通线路中的常见结构物，隧道在西部地区越修越多。由于西部属于多山且复杂地质地区，因此，这些隧道都不同程度的受到各种地质灾害的影响，其中高岩温便是较为突出的一种地质灾害。地温较高不仅影响隧道的建设和运行，而且对隧道衬砌结构的安全性产生不利影响。 本文以高海拔、高岩温地区隧道—吉沃希嘎隧道工程为依托，通过现场实测、结合传热学理论基础，采用ANSYS有限元软件进行数值模拟计算，研究了高海拔、高岩温地区隧道所在山体初始温度场分布规律，并以此为初始条件，对二次衬砌在温度场和应力场耦合作用下的应力分布进行了较为细致的研究。最后，通过在初支和二次衬砌之间设置隔热层，研究了隔热层对二次衬砌温度场分布的影响。论文主要工作及成果如下： （1）运用ANSYS有限元软件数值模拟了隧址区初始地温场分布规律，得知地表以下25m左右为恒温层，恒温层温度约为26℃，恒温层至地表之间为变温层，变温层温度受外界影响较大，恒温层往下为增温层。 （2）比较隧道开挖初始实测的岩温与数值模拟计算出的岩温，发现两者最大温度差仅为4.6℃，两者数据基本吻合，从而检验了数值模拟的精确性与可靠性。 （3）以隧址区初始地温场为初始条件，模拟了隧道二次衬砌在温度场和应力场耦合下的应力分布情况。就断面二而言，结果显示，仅有重力载荷作用时，仰拱承受的拉应力为2.09MPa，最大压应力分布在拱脚处，为12.3MPa；当同时施加重力和温度载荷后，仰拱承受的拉应力增大到2.14MPa，变化较大，最大压应力仍分布在拱脚处，为8.66MPa。 （4）对于断面二，同时施加温度载荷及重力后，仰拱承受的拉应力随时间的推移逐渐减小；拱脚处的压应力持续增大，但变化幅度很小，由加载一个月后的8.42MPa增大到加载五年后的8.66MPa。 （5）由ANSYS有限元软件数值模拟计算结果可知，无隔热层时，衬砌施作五天后的最大温度为45.976℃，分布在衬砌外边缘，最小温度分布在仰拱处，为28.342℃。在初支和二次衬砌之间设置了10cm厚的隔热层，加载五天后，衬砌的最大温度为30.226℃，同样分布在衬砌外边缘，最小温度为28.024℃，，分布在仰拱处。由此可见，隔热材料在很大程度上抑制围岩的高温向隧道内传递。
[Abstract]:With the development of the western development strategy, as a common structure in the traffic lines, more and more tunnels are being built in the western region. Due to the mountainous and complex geological area in the west, these tunnels are affected by various geological hazards to varying degrees, among which the high rock temperature is a more prominent geological hazard. The high ground temperature not only affects the construction and operation of the tunnel, but also adversely affects the safety of the tunnel lining structure. In this paper, based on the tunnel engineering in high altitude and high Yanwen area, the high altitude is studied by using the ANSYS finite element software, based on the field measurement and the theory of heat transfer. The distribution law of initial temperature field of the mountain in which the tunnel is located is studied in detail under the coupling of temperature field and stress field. Finally, the influence of thermal insulation layer on the temperature field distribution of secondary lining is studied by setting insulation layer between primary and secondary lining. The main work and results are as follows: (1) the distribution of initial ground temperature field in tunnel area is numerically simulated by using ANSYS finite element software. It is known that there is a constant temperature layer about 25 m below the ground surface and a constant temperature layer temperature of about 26 鈩
本文编号：2147322
[Abstract]:With the development of the western development strategy, as a common structure in the traffic lines, more and more tunnels are being built in the western region. Due to the mountainous and complex geological area in the west, these tunnels are affected by various geological hazards to varying degrees, among which the high rock temperature is a more prominent geological hazard. The high ground temperature not only affects the construction and operation of the tunnel, but also adversely affects the safety of the tunnel lining structure. In this paper, based on the tunnel engineering in high altitude and high Yanwen area, the high altitude is studied by using the ANSYS finite element software, based on the field measurement and the theory of heat transfer. The distribution law of initial temperature field of the mountain in which the tunnel is located is studied in detail under the coupling of temperature field and stress field. Finally, the influence of thermal insulation layer on the temperature field distribution of secondary lining is studied by setting insulation layer between primary and secondary lining. The main work and results are as follows: (1) the distribution of initial ground temperature field in tunnel area is numerically simulated by using ANSYS finite element software. It is known that there is a constant temperature layer about 25 m below the ground surface and a constant temperature layer temperature of about 26 鈩
本文编号：2147322
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