Experimental Study on Temperature Field Distribution of Tunnel Lining Structure in Fire Accidents
Zhu He-hua · Journal of Tongji University · 2012
An experimental study was made of the temperature field distributions of tunnel lining structure under high temperature.The content of research includes variation of temperature of lining structure with time,temperature field distribution along thickness of lining structure and effect of boundary condition on temperature field distribution.HC curve with about 60 min period of duration of heating and testing lining segments casted by C50 concrete are employed in the experiments.The results indicate that due to water evaporation of concrete,temperature of lining structure stops increasing when its temperature reaches to 100~115 ℃.With the increase of distance from the heating face of the lining structure,the phenomenon of stopping increasing temperature occurs later and the period of duration increases.Furthermore,the temperature field distribution along the thickness of lining structure can be described by exponential decay curve.Finally,due to heat absorption by surrounding soil the temperature of lining structure is lower than the ones exposed to atmosphere,and the closer to the boundary,teh larger the difference.