Monitoring and geological advance prediction for tunnel construction: A case study of shangzhuang tunnel

Abstract

During real-time tunnel construction in geologically complex areas, the settlement of rock formations with special physic-mechanical properties and freshly constructed tunnel segments have a serious impact on the progress and safety of the project. Therefore, the implementation of tunnel monitoring and advance geological prediction are important for tunnel construction. The mountain body where the Shangzhuang Tunnel is located is typically characterized by poor mechanical properties, rock fragmentation and weak stability. The vault subsidence, peripheral convergence inside the tunnel and surface settlement outside the tunnel were monitored by total station instrument; and the geo-radar was used to realize the geological advance prediction. The results show that, the change curves of vault subsidence and peripheral convergence with tunnel length have the same trend, which increase first and then decrease in general. Anomalous deformation of 8.7 mm was observed at the mileage of 683 m. The results of geological advance prediction are consistent with the on-site observation, which can provide reference for the safe, smooth and economic construction of the tunnel project.