Recently, Nepal Sunkoshi Marin Diversion Tunnel Project Department completed 1136 meters of TBM excavation in May, and the production of segments broke through 620 rings in a single month, which once again refreshed the previous record of 1069 meters of TBM tunnel excavation and 615 rings of segment production in a single month set by the project department.
In the process of TBM excavation, weak surrounding rocks such as strongly weathered, fragmentized gneiss and schist continue to appear in the tunnel geology. Faced with the harsh geological conditions, the TBM team of the project has achieved the goal of sustained, balanced, and rapid TBM excavation and created the highest daily footage by strengthening geological advance prediction, rationally adjusting cutters, installing over-excavation cutters, increasing grouting volume, refining organizational processes, maintaining equipment maintenance, and supporting the supply of materials and equipment—the tunneling record of the highest weekly footage 296.23 meters.
To fully guarantee TBM tunnel excavation and efficiently complete the goal of ensuring supply, a set of complete and smooth production procedures has been established around personnel input, material entry, equipment maintenance, and so on. Through a series of measures, the monthly output of segment production in the project department has soared from 525 rings at the beginning of the year to 620 rings, reaching 124% of the design capacity of 500 rings.