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Abstract The cement can not hydrate sufficiently and uniformly at low temperature，so it?s easy to arouse rise the problem with lack of strength and appearing penetration cracks for tunnel concrete lining in cold regions during winter. According to the temperature control equation including low temperature phase transition，beginning with the study of influence of excavation time on temperature distribution of surrounding rock，considering the heat of hydration of concrete，the heat transfer law between surrounding rock and concrete lining was analyzed，and the influence of environment temperature in tunnel，heating temperature and time on the change rule of concrete temperature was studied. The results show that the influence scope of environmental temperature on the temperature of surrounding rock increased with the increase of excavation time；after a period of heated time，the temperature of surface and deep surrounding rock became higher than the middle?s，formed a temperature distribution of hot at two head，cold in the middle；the lowest temperature of concrete lining in 24 hours increased with increasing of heating time，heating temperature and environmental temperature. Based on this，a concise and practical heating time calculation formula was put forward. The in-situ results show that the goals were realized about the lining concrete can continuously and efficiently constructing，its surface has no crack and the actual strength＞C30 by applying the proposed calculation formula.
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Received: 20 June 2012
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2013, Vol. 32 
