寒区隧道衬砌电加热试验研究

寒区隧道冬季易出现衬砌破损甚至滴水结冰等冻害，为此，除了做保温层外，主动加热系统也是必要的，主动加热系统主要由二次衬砌和保温层间的电热带组成.为了模拟隧道衬砌混凝土表面滴漏水结冰后从负温加热至正温的工况，对负温条件下的混凝土试件进行电加热模型试验研究，包括对单独试件及三联试件进行加热试验.结果表明:在采用长度2m、功率30W、埋置深度10mm的电热带，并选用40mm厚的聚氨酯板作为保温层时，混凝土试件表面温度能够在60min之内从-4℃升高至0℃以上.研究成果可为寒区隧道融冰防冻提供指导.

Experimental Study on Electric Heating of Tunnel Lining in Cold Region

In winter， frost damage of tunnel such as lining damaged or even dripping and freezing often occurs in cold region. Therefore， the active heating system is necessary except for the insulation layer. The active heating system is mainly composed of the electric heating belt between the secondary lining and the insulation layer. In order to simulate the heating process of freezing-dripping-water tunnel lining， electric heating model tests on concrete specimen， including single specimen and triple test piece， was conducted from a negative temperature to a positive temperature. The results show that the surface temperature of the concrete specimen can be increased from -4℃ to over 0℃ within 60 minutes， if the electric heating belt with a length of 2 m， power of 30W， embedded depth of 10 mm and the polyurethane board with a thickness of 40mm are used as insulation layer. The research results can provide guidance for ice melting and antifreeze of tunnels in cold regions.