Large surface settlement is often caused when there are tunnels constructing in the upper-soft lower-hard ground. Taking the antuo-mountain entrance/exit lines of Shenzhen subway line 7

which pass under the North ring Road

as an example

the essay combines numerical simulation with field monitoring to make researches. Based on the utilization of monitoring measurement

the essay analyses the surrounding rock and s stratum deformation law during the tunnel pass under the existed road. The result shows: The loading on road surface has significant impact on settlement of tunnel surrounding rocks. When the distance between twin tunnels is relatively small

the full-section grouting method obviously influenced the deformation of shallow strata above the grouting interval

and so is the deeper part near the tunnel. Full-section grouting method has positive effect on surface settlement controlling

while it is important to concern the upheaval. In this project

the full-section grouting method impact harder on the parts which is 8 meters beyond the reinforcing ring. And the full-section grouting method impact weaker on the parts which is 8-13 meters beyond the reinforcing ring. The comprehensive application of various monitoring methods ensures the construction safety.