以京珠复线长沙至湘潭高速公路邓家湾隧道为依托,针对该隧道左线进口端位居山谷地带、开挖断 面大、覆盖层薄、围岩破碎等特点,提出在洞身开挖范围内采用地表竹管注浆,而在边坡外侧采用倾斜地表钢管注浆预加固方案.暗挖实施效果表明:通过地表注浆预加固,改善了围岩的物理力学性能,缩小了开挖变形产生的松弛区范围,加快了施工进度,确保了施工安全,取得了较好的经济和社会效益.%Taking Changsha-Xiangtan highway of a double track from Beijing-Zhuhai Expressway Dengjiawan-tunnel as an example, based on the left route entrance of the tunnel in the valley region, excavation section large, covering layer thin, rock crushing, etc,this thesis puts forward excavation scope within the body in the tunnel with the bamboo tube grouting, and in the outer slope by tilting the grouting steel pipe pre-reinforcement scheme. After the implementation of ground grouting pre-reinforcement, implement results show that the physical and mechanical performances of the rock were improved, the scope of the relaxation area due to excavation narrowed, construction progress quickened . It ensure the construction safety and good economical and technical results were obtained.
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