On January 10, the left tunnel of the Luotuoshan Tunnel of the Taiyuan Northwest Second Ring Expressway, which China Railway Sixth Group constructed, was completed.
Luotuoshan Tunnel is located in Beishan Village, Nitun Town, Yangqu County, and Xilingjing Village, Xilingjing Township. It is designed with two tunnels and four lanes. The left tunnel is 7158 meters long, and the right tunnel is 7172 meters long. It is the control project of the whole line. The geological conditions of the tunnel are complex, with Grade IV and V surrounding rocks accounting for 45. 8% and 10. 7% respectively. The terrain is undulating, the surface weathering is severe, and there are dissolution cracks on the local trench wall. The construction is complex, and the safety risk is high.
The whole section of the project is constructed by the bench and reserved core soil methods. After the inclined shaft enters the main tunnel, the maximum number of working faces is 7. Faced with the problems of soft surrounding rock and complex geological conditions, the project department, after many investigations, adopted the construction of a pipe shed into the tunnel, strengthened the advanced support, and enhanced the self-stabilization ability of the surrounding rock. To ensure the safety and efficiency of construction, the project department has an anti-collapse detection and early warning system and advanced tooling such as a three-arm drilling jumbo.
The tunnel is located in a nature reserve with high environmental protection requirements. The project department conducts environmental impact assessments, formulates special construction plans, and strictly implements ecological protection measures to ensure that construction noise, dust, and wastewater discharge meet the standards.
