Study On Construction Security Evaluation Of Subsea Tunnel With Large Cross-Section

Monitoring measurement and deformation control criteria of road tunnels with large cross-section which excavated by CRD method has been one of focal points for expressway tunnel engineering. Focused on Xiang'an subsea road tunnel, making use of the data of monitoring measurement and 3D numerical calculation, this paper analyzes the distribution law of crown settlement, convergence of tunnel inner perimeter, deformation of temporary support,effect of removal temporary support. Furthermore, the deformation control criteria of large cross-section tunnel which excaved by CRD method has been studied further and the accuracy of result of data analysis proved by 3D numerical calculation.Focused on Xiang'an subsea road tunnel, the deformation distribution law of different excaved method of CRD method has been concluded and the crown settlement regression curve has been concluded by regression analysis firstly, then combined with practical situation of tunnel model has been built to 3D numerical calculation. Fanally, established control criteria of crown settlement in accordance with the data of monitoring measurement.The paper presents the data analysis method of monitoring measurement to large cross-section tunnel which excaved by partial excavation method,the analysis method of temporary supportion deformation,the principle of establishing control criteria in fortes road tunnels which excaved by CRD method, the deformation control criteria of crown settlement and the deformation control criteria of temporary supportion.