Analysis of the effect of tunnel construction on frame structure buildings in Xiamen Airport Road

Wu Cun Shan Tunnel in Xiamen Airport Road Phase I Project is a shallow-buried, large-span and hidden-digging tunnel which passes through high-density building cluster under complicated geological conditions. 67 buildings are being influenced by tunnel construction along the tunnel. In order to ensure the safety of surface buildings in the tunnel construction, CRD excavation method are adopted in some sections which initiates a precedent of construction of double-arch tunnel with CRD method in China. The effect of tunnel construction on frame structure buildings is analyzed through site monitoring of surface building settlement, crack development in this paper. The results show that excavation of tunnel face CRD1~5 has the most important influence on the building settlement. The longer the construction period is, the greater building settlement and crack width change, and vice versa. Grouting in the tunnel can decrease building settlement caused by tunnel excavation effectively. The main reason that causes building cracking and development of cracks existed is uneven settlement. And the ability of the building to resist down concave deformation is stronger than that to upper convex deformation. While width variation of cracks lags behind variation of uneven settlement. Cracks caused by tunnel construction mainly distribute around the door and window openings in the longitudinal filler wall and the connection part between frame beam-column and filler wall.