China's largest domestically developed and manufactured slurry balance shield tunneling machine, the "Yunhe," has recently been put into operation in the Beijing East Sixth Ring Road underground renovation project.

　　The East Sixth Ring Road renovation project starts from the Jingha Expressway interchange in the south and extends north to Luyuan North Street, with a total length of about 16 kilometers. The shield tunnel section is about 7.4 kilometers long, and the finished tunnel has an outer diameter of 15.4 meters, making it the largest-diameter shield tunnel in China at present.

　　The super-large-diameter shield tunneling machine "Yunhe," tailor-made for the East Sixth Ring Road renovation project, consists of a cutterhead, a shield body and five sets of trolleys, with a total weight of about 4,500 tons. It applies world-advanced technologies and equipment such as independently developed automated segment assembly technology and an intelligent remote safety monitoring and management system. It will pass through the core area of Beijing's Municipal Administrative Center, crossing over or under multiple roads, rail lines and rivers, and at its deepest point it will pass beneath the integrated hub of the Municipal Administrative Center Station at a maximum depth of about 59 meters.

　　At present, the daily advance is about 1 meter; after the trial excavation is completed, the daily advance can reach 10 meters.

　　The East Sixth Ring Road renovation project is a key project in Beijing and can effectively strengthen traffic connections on both sides of the East Sixth Ring Road, integrating the Tongzhou urban area with the administrative office area of the Municipal Administrative Center.