金家庄螺旋隧道施工通风方案优化数值模拟

Numerical Simulation of Scheme optimization of Construction Ventilation of Jinjiazhuang Spiral Tunnel

本文以金家庄特长螺旋隧道为依托,运用三维数值计算方法,采用风仓与隔板风道组合式通风方案对既有压入式进行优化。研究表明:(1)采用既有方案,第一、二阶段均不能满足供风量要求,采用优化方案可满足要求,且风机总功率最大降低58%;(2)第二阶段通风,既有方案最多同时向两个掌子面供风,优化方案最多同时向三个掌子面供风,加快施工进度;(3)第三阶段通风,既有方案出现回流,通风120min,隧道中CO仍未降至控制标准以下,采用优化方案通风90min,CO浓度降至控制标准以下。

Based on the Jinjiazhuang super long spiral tunnel,this paper uses the three-dimensional numerical calculation method to optimize the existing forced ventilation scheme.The results show that:(1) the existing scheme can not meet the air supply requirements in the first and second stages.After the optimized scheme is adopted,the air supply requirements can be met,and the total power of fans can be reduced up to 58%compared with the existing scheme.(2) In the second stage of ventilation,the existing scheme can supply air to two working faces at most,and the optimized scheme can supply air to three faces at most at the same time.(3) In the third stage of ventilation,the existing scheme has reflux problem,and the CO in the tunnel can not be reduced below the control standard for 120 min.With the optimized scheme,the CO in the whole tunnel can be reduced below the control standard for 90 min.