TBM施工引水隧洞降温技术研究

TBM施工时，岩温和机械发热所产生的大量热量会导致隧洞内的温度环境恶化，TBM掘进面附近的温度控制是影响连续长距离掘进的重要因素之一。为制定合理的TBM施工段降温措施，采用传热学理论，对采用压入式独头通风的TBM施工隧洞内的温度分布规律进行研究，并以引汉济渭岭北段TBM 5#斜井工区为例进行验证。通过引入空调工程中焓值的概念，确定TBM隧洞人工降温的冷负荷，对常见的降温措施进行对比讨论，进而确定TBM施工隧洞的降温措施。研究表明： 隧洞内的空气温度与隧洞壁温、通风风温、通风风量、盾构的发热功率、隧洞周长、通风长度、风管侧壁传热系数和隧洞侧壁的换热系数等参数有关；对于TBM掘进面附近高温、高湿的环境，只能采取人工制冷降温措施进行降温

Study of Cooling Technology for Long TBM Water Diversion Tunnel

During the construction of TBM tunnel, the temperature environment inside the tunnel will deteriorate due to the large amount of heat generated by the rock temperature and the mechanical heating. The temperature control near the TBM excavation face is one of the important factors influencing continuous long distance excavation. In order to formulate reasonable cooling measures for TBM section construction, the heat transfer theory is adopted to study the temperature distribution law with dead end forced ventilation tunnel. The law is certificated by the test data of work area of TBM inclined shaft #5 in the north section of Hanjiang River Weihe River Water Conveyance project. By introducing the concept of enthalpy in air conditioning engineering, the load of artificial cooling of TBM tunnel is determined, and common cooling measures are compared and discussed, so as to determine the cooling measures of TBM tunnel construction. The study results show that: (1) The air temperature in the tunnel is associated with the tunnel wall temperature, ventilation air temperature, ventilation air volume, heat generation power of shield in the tunnel, tunnel circumference, ventilation length, heat transfer coefficient of the sidewall of the air duct and heat transfer coefficient of the sidewall of the tunnel. (2) For the environment of high temperature and high humidity near the tunneling face, only artificial refrigeration cooling measure can be used to reduce the temperature.