Manufactured by China Railway Construction Heavy Industry Corporation Limited(CRCHI), the TBM "Jinghua" was off the assembly line on September 27th, 2020 at CRCHI Changsha headquarters, with an excavation diameter of 16.07m. This 4,300-tonne, 150m-long slurry TBM is the first set of its kind to have been made in China.
The Beijing East Sixth Ring Road Reconstruction Project extends from the south, starting at the Beijing-Harbin Expressway, to the north, ending at Luyuanbei Street. It is designed with a speed limit of 80 kilometers per hour and has a total length of approximately 16 kilometers. The underground section of the project is about 7.4 kilometers and is constructed by TBM tunneling method. The tunnels are arranged in a separated dual-tunnel configuration, divided into three layers. The upper layer serves as a smoke extraction channel, the middle layer accommodates a three-lane expressway, and the lower layer serves as an evacuation and rescue channel. With a maximum burial depth of 75 meters, it is the deepest underground tunnel in Beijing.
This TBM tunnel construction of this project has numerous construction challenges, including "mega large diameter, super long distance, ultra deep burial depth, and extra sensitive environment". The machine has a series of advanced innovative technologies and numerous independent core technologies aimed to ensure the rapidity and safety of tunneling in complex geological conditions, which is mainly composed of sandy soil, water-rich and high-density sand, interactive layers of silt and cohesive soil.
Since the launching of the TBM "Jinghua "in May 2021, it created outstanding performance with a maximum daily advance rate of 24 meters and a maximum monthly advance rate of 542 meters. On September 25th, 2022, the TBM reached the intermediate air shaft with precise breakthrough and no problems.
Beijing East Sixth Ring Road Reconstruction Project is a landmark project in the construction of Beijing's sub-center. After the opening to traffic, the project will promote the integration of Tongzhou District and the administrative office area of the sub-center, significantly improve Beijing's transportation services, promote the integration of transportation in the Beijing-Tianjin-Hebei Region, and build a comprehensive transportation system.