Press release - In September 2022, the Beijing East Sixth Ring Road Reconstruction Project reported more good news. The CRCHI mega slurry TBM "Jinghua" reached the intermediate air shaft smoothly with no problems, marking that the project has achieved another great success.
The maximum excavation diameter of the slurry TBM "Jinghua" is 16.07 m, the length of the whole machine is 150 meters, and the total weight is 4300 tons. “Jinghua”, which is the largest shield machine in China has implemented a series of targeted optimal design and system integrations such as :-
- - the fourth-generation accessible cutter exchange technology
- - telescopic main drive
- - extreme high pressure auto-compensation
- - large power slurry circulation system
- - and synchronous double-liquid grouting
The successful application of synchronous double-liquid grouting technology has realized the millimeter-level control of ground settlement, ensured zero disturbance to existing buildings on the ground during TBM construction, and filled the gap of synchronous double-liquid grouting in mega slurry TBM construction in China.
The tunnel length is 7,338 meters and its complex geology is mainly composed of sandy soil, water-rich and high-density sand, interactive layers of silt and cohesive soil. The project also faced construction difficulties such as super-deep soil cover, and a super-sensitive environment.
The slurry TBM has successfully excavated 4,772 meters and reached the intermediate air shaft after 16 months since it began its initial excavation. The slurry TBM has successively overcome technical difficulties such as the initial excavation with shallow overburden and long-distance crossing high-density sand layers. The slurry TBM continuously crossed the Beijing-Harbin Railway and Beijing sub-center comprehensive transportation hub with micro-settlement and non-disturbance. It created 542 meters excavation record in a single month.
The Slurry TBM "Jinghua" will carry out a second excavation after finishing a TBM inspection and maintenance in the intermediate air shaft, and will continue to excavate a further 2.6 kilometers forward to reach the receiving well in Wansheng South Street. At that time the tunnel excavation work will be completed.
For further information on this project please visit the CRCHI website https://en.crchi.com//. 41/22.
