A case of a frame building in Guangzhou was employed for investigating the effect of tunnel construction on adjacent buildings

including foundation total settlement

differential settlement

and building torsion and inclination.A tunnel-soil-structure numerical model was established by using the software FLAC3 D

and a total of 11 cases were calculated with the building middle axis being parallel to the tunnel axis while their horizontal distance varying between 0 m and 20 m.The numerical results show that both the maximum foundation settlement and the maximum building torsion decrease from their maximum values to zero with the increase of the horizontal distance between the building and the tunnel.Meanwhile

the maximum building torsion decreases rapidly and becomes negligible when the horizontal distance is greater than the depth of the tunnel axis.However

the building inclination and the differential settlement of two adjacent footings increase initially

then reach their peak values at the inner edges of the settlement trough

and finally decrease to zero.The numerical results indicate that the footing settlement and building torsion

caused by tunnel construction

should be monitored for frame structure buildings located above the underground tunnel;in contrast

the building inclination and differential settlement should be monitored for those located at the edges of the settlement trough.