关角隧道大变形处理技术

Large Deformation Treatment Technology of Guanjiao Tunnel

关角隧道全长32.645 km,为目前国内在建的最长的单线铁路隧道。隧道通过区岩性极其复杂,沉积岩、岩浆岩、变质岩三大岩类均有出露,断裂构造极为发育,通过大小不等断层共17条,其中二郎洞断层束长达2 355 m,且具有一定的高地应力。受复杂地质的影响,关角隧道施工中发生了不同程度的大变形,最大变形达到了505 mm,现场对发生变形段采取了横撑、长锚杆、径向注浆、二次支护等措施进行加强,对未开段采取了加强初期支护、双层初期支护、调整初期支护曲率等措施来抑制变形并取得了成功。

Guanjiao tunnel is the longest single-track railway tunnel under construction in China,with a total length of 32.645 km.The geological conditions are extremely complicated.There are 17 major faults,among which Erlangdong fault（2 355 m） contains high earth stress,with sedimentary rocks,igneous rocks and metamorphic rocks included in this section.Large deformation occurs during construction because of complicated geological conditions,the maximum deformation being 505 mm.Crossbars,long bolts,radial grouting,secondary support and other measures are taken to strengthen surrounding-rock in deformation fields.Measures（strengthening primary support,using double primary support,revising the curvature of primary support,et al） are successfully taken to control the large deformation in non-excavation fields.