粤赣高速公路龙祖山隧道洞口浅埋段施工

粤赣高速公路龙祖山隧道左、右洞上陵端浅埋且为软弱的全风化花岗闪条岩地段，施工采取了明、暗挖方案，洞外采用套拱、护拱、钢花管注浆加固岩体以及对洞前边坡、洞口仰坡采用钢花管注浆加固措施，洞内采用多台阶短开挖、加强支护、改变传统砂浆锚杆为注浆锚管等施工技术，这些措施控制了全风化花岗闪长岩遇水崩解坍塌的地质病害，成功地开通了浅埋软岩地段，至今山体稳定，隧道结构安全。

Construction of Shallow-Buried Section of Longzu Mountain Tunnel Entrance on Yue-Gan Expressway

On the basis of the construction of the shallow-buried section of the Shangling end entrance of Longzu Mountain Tunnel on Yue-Gan Expressway, some construction methods are introduced, including open cut and covered cut methods, uses of lag arch and protection arch on the outside of the tunnel,steel pipe grout for stabilizing the round rock and slope, adopting much and short benches for the tunnel driving, strengthing bracing, and changing traditional mortar anchor rods into grouting anchor rods. The practice shows that the techniques control the devolution of the decayed granite and diorite, make the tunnel passes through the shallow-buried soft rock section successfully and ensure stability of the piedmont and salty of the tunnel structure.