临近导热断层高岩温隧道施工环境温度控制技术研究

Study on the Ambient Temperature Control Technology for Construction of a Tunnel Near Heat-conducting Fault and with High Rock Temperature

为研究临近导热断层高岩温隧道施工环境温度控制技术,依托某高岩温隧道工程,对机械通风、机械通风+冰块、机械通风+喷雾、机械通风+冰块+喷雾等方案的降温效果进行研究。结果表明,机械通风量越大,降温速度越快,降温温差越大;当机械通风量增加到一定程度后,隧道环境降温效果提升不再明显,需采取其他辅助措施进行进一步降温;冰块辅助降温时用冰量越大,降温速度越快,降温效果越明显;机械通风+冰块+喷雾控温方案平均降温速度为5.37℃/min,降温温差为53.74℃,稳定环境温度为26.26℃,对隧道施工环境温度的控制效果最好;现场采用该控温方案后,掌子面岩温降至46.1℃,洞内环境温度在25~27℃间,符合规范要求。

In order to investigate the ambient temperature control technology for construction of a tunnel near heatconducting fault and with high rock temperature,the cooling effectiveness of the solutions including mechanical ven⁃tilation+ice,mechanical ventilation+mist spray and mechanical ventilation+ice+mist spray has been studied under different mechanical ventilation rates by using a tunnel project with high rock temperature as the study case.The results indicate:greater mechanical ventilation rate enables faster cooling rate and greater temperature drop;when mechanical ventilation rate is increased to a certain level,the tunnel cooling effectiveness is no longer im⁃proved notably,and other auxiliary measures are needed to further reduce temperature;in cooling by ice,consump⁃tion of more ice will bring faster cooling rate and better cooling effectiveness;in the mechanical ventilation+ice+mist spray solution,the average cooling rate is 5.37°C/min,temperature drop is 53.74°C and the stable ambient temperature is 26.26°C,so this solution is the most effective solution for ambient temperature control in tunnel con⁃struction;when this temperature control solution is applied on site,the rock temperature at tunnel face is reduced to 46.1°C and the ambient temperature in tunnel is 25~27°C,which meets the applicable standard.