The entrance of Meiziao tunnel on Xiang-Gui railway passes through a long, unstable slope with shallow cover. Through the construction option comparison and security identification, it was detemined to excavate firstly the surface layer of the slope body and to reinforce the surface by wire-meshed shotcreting. On the section of main tunnel the ground was consolidated by grouting through steel tubes, changing the physico-chemical structure of soils and surrounding rocks, enhacing their strength and integrity. Main tunnel excavation adopted long pipe-roofing and CRD method (I. E. Overlapped intermediate walls method) , further reducing the disturbance to the surrounding rocks in the construction process, thereupon the excavation through the long, unstbale, uneven-pressured and shallow slope was smoothly completed.%湘桂铁路梅子坳隧道进口段穿越长大不稳定斜坡体,此斜坡体为严重浅埋、偏压地段,施工难度大.经施工方案比较及安全性论证,施工中采取先对偏压山体进行刷坡并采取锚网喷防护,并对开挖洞身范围内地表和岩体进行钢化管注浆预加固处理,改变土体和围岩物理化学结构,强化围岩自身强度和整体性；洞身开挖采取长管棚加CRD工法(即交叉中隔壁法)施工,进一步减小施工过程中对围岩的扰动,顺利穿越浅埋偏压长大不稳定斜坡体.
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