The largest diameter pipe jacking machine in China broke through in an urban underground common trench project recently. The machine named “Tiejun” was manufactured by CRCHI.
The project is the largest diameter circular pipe jacking project in China. It is an important part of the underground common trench in Nanjing. The infrastructure shall effectively improve the safety level of utilities pipelines and the city’s disaster prevention and resilience capability.
The geological conditions and surrounding environment of the project are extremely complex. It goes cross rivers, ancient city walls, municipal roads and railways. Multiple 220 kV high-voltage lines were relocated and reconstructed.
Geology: uneven soft and hard ground. Extremely high requirements for ground settlement control. Extremely high safety risks and huge difficulties of construction.
The excavation diameter of the slurry balanced pipe jacking machine is 5.47 meters, with 7m length primary machine and about 300 tons total weight. It is the first time to adopt jaw crusher system, advance geology forecast system, automatic bentonite grouting technology, and excavation chamber visualization technology.
Up to now, the hard rock pipe jacking machine, fast roofing machine, retractable piperoof machine, and pipe-jacking and shield TBM integrated machine developed by CRCHI have been widely used in diversion and drainage tunnels, power tunnels, oil pipelines, and underground common trenchs.
