修建城际地下铁路隧道存在的步距问题与相关建议

以莞惠城际轨道交通工程松山湖隧道施工为例,通过对隧道各工序作业时间分析、隧道设计与施工类比和施工模型图说明,认为铁建设2010]120号文在修建城际地下铁路隧道方面尚存在一定的适应性和可操作性的问题,并提出以下建议:1)Ⅵ级围岩隧道,初期支护封闭成环位置距离掌子面由原35 m调整为50 m,二次衬砌距离掌子面由原70 m调整为85 m(除文中所述几种特殊情况外);2)Ⅴ级围岩隧道,初期支护封闭成环位置距离掌子面由原35 m调整为55 m,二次衬砌距离掌子面由原70 m调整为90m;3)Ⅳ级围岩隧道,初期支护封闭成环位置距离掌子面由原35 m调整为65 m,二次衬砌距离掌子面由原90 m调整为120 m。

Comments on Distance between Primary Support/Secondary Lining and Working Face of Inter-city Underground Railway Tunnels

In this article,the construction cycle time and construction model of Songshanhu tunnel on Dongguan-Huizhou inter-city railway are analyzed,and comparison and contrast is made between national railway tunnels and inter-city railway tunnel.It is believed that the requirements specified in Tiejianshe No.2010]120 are not applicable to the construction of inter-city railway tunnels.Proposals made are follows：1 ）For inter-city railway tunnels in Grade Ⅵsurrounding rock,the distance between the primary support and the working face should be optimized from 35 m to 50 m,and the distance between the secondary lining and the working face should be optimized form 70 m to 85 m;2）For tunnels in Grade Ⅴ surrounding rock,the distance between the primary support and the working face should be optimized from 35 m to 55 m,and the distance between the secondary lining and the working face should be optimized form 70 m to 90 m;3 ）For tunnel in Grade Ⅳ surrounding rock,the distance between the primary support and the working face should be optimized from 35 m to 65 m,and the distance between the secondary lining and the working face should be optimized from 90 m to 120 m.