中文摘要：

隧道掘进过程中,掌子面和碎屑流地层之间的距离小于安全距离时,在高水压和高地应力的共同作用下,掌子面会由于经受不住其后方的水土压力而发生碎屑流.基于摩尔-库伦准则和极限平衡法,推导出隧道碎屑流安全距离的计算公式,并分析了各参数的影响.分析结果表明,安全距离随碎屑流地层水头高度、隧道洞径的增大而增大,随岩盘处和碎屑流地层处的内摩擦角和黏聚力的增大而减小.通过引硫济金引水隧洞和祁连山铁路隧道典型实例对公式进行了验证与分析.

英文摘要：

In the process of the excavation of tunnel,when the distance between working face and debris flow strata is less than the safe distance,the tunnel debris flow will happen,because the working face cannot withstand high water pressure and high ground stress. Based on Mohr-Coulomb criterion and limit equilibrium method,the formula for the safe distance of tunnel debris flow was deduced,and influence on various parameters were analyzed. The results show that safe distance increases with the increase of the water head and diameter of tunnel in debris flow strata,and decreases with the increase of angle of internal friction and cohesion in both laccolith area and debris flow strata. Yinliujijin diversion tunnel and Qilianshan railway tunnel are used as typical examples to verify the formula.