丰沙铁路8号隧道内落石分析及处理措施

丰沙铁路8号隧道由于修建时间较早,部分段落为无衬砌隧道,经过长时间的风化、振动及地下裂隙水等因素影响,无衬砌段发生了围岩脱落,严重威胁行车安全。经过地质勘察,分析围岩脱落的形成原因,通过地质雷达无损探测结合理论分析,确定围岩松动圈的厚度,结合铁路的实际运营、宽度限界条件、施工条件等,通过方案对比,采用TECCO柔性防护网、注浆等方式对无衬砌段进行防护,长短锚杆结合的方式稳定防护网,并通过有限元分析长锚杆注浆对围岩位移、应变的改善作用。通过这些加固措施,最终达到了防止围岩脱落,加固无衬砌隧道的目的。

Rock-fall Analysis and Treatment Measures for No.8 Tunnel on Fengtai to Shacheng Railway

The railway of Fengtai to Shacheng No.8 Tunnel was constructed in an early time and some sections of it are without lining. Due to the lone time weathering,vibration and underground fissure water erosion,surrounding rock-fall is encountered in those sections,which imposes threat to the traffic. After a detailed geological survey and the analyses of the causes of surrounding rock-fall,the thickness of rock loose zone is determined via geological radar non-destructive detection and theoretical analysis. Based on the actual operation,tunnel clearance,construction condition and other factors,TECCO flexibility protect system and grouting are employed to treat the unlined sections together with anchor bolts of long and short,and the stability of surrounding rock is analyzed with the finite element calculation. All these reinforcing measures are proved successful in preventing rock-fall and reinforcing unlined tunnel.