On November 28th,突发新闻 with the completion of the last concrete pouring, Bid 03A2 of the comprehensive transportation hub project of Beijing City Sub-center Station, which was undertaken by China Construction First Bureau, successfully achieved the overall capping of the main structure. This bid is also the first "underground hub above the city" project to achieve the capping of the main structure of the comprehensive transportation hub project of Beijing City Sub-center Station, and fully promotes the people of the city sub-center to realize their expected ideal and convenient life as soon as possible. At the same time, it also marks that the sub-central station hub project of China Construction No.1 Bureau will enter a new construction stage in an all-round way. Next, the indoor secondary structural masonry and electromechanical installation work will be started in bid 03A2. It is estimated that by the second half of 2024, the rail transit, public service space, municipal supporting facilities and comprehensive transportation hub supporting projects with a construction area of 73,000 square meters will be fully completed.
The comprehensive transportation hub project of Beijing City Sub-center Station is located in Tongzhou District, Beijing, with the north canal bank in the west and the East Sixth Ring Road in the east. It is located at the intersection of the "One Belt and One Axis" spatial structure of the city sub-center. Upon completion, it will become the largest underground comprehensive transportation hub in Asia and an important link connecting Beijing Capital International Airport, Daxing International Airport, Tangshan, Tianjin Binhai New Area and xiong'an new area, providing more diverse, convenient and comfortable transfer passages for people in Beijing-Tianjin-Hebei region, greatly enhancing the influence of Beijing-Tianjin-Hebei economic circle.
How to prevent water and seepage in ultra-deep and super-large foundation pit
There is an ultra-deep and super-large foundation pit in the project, and the groundwater level within the site is about 13 meters, including one layer of diving and four layers of confined water. The project team used soil nailing wall-underground continuous wall-prestressed anchor cable as the foundation pit enclosure structure, and monitored the foundation pit in all directions. The monitoring data were connected to GIS platform and BIM management platform, and the settlement and displacement changes of the foundation pit supporting structure were analyzed, thus effectively avoiding the water seepage problem during construction.
How to "Be as Steady as Mount Tai" for Super-massive Steel Structure
The maximum weight of steel structure monomer in the project can reach 50 tons, and the construction of steel bar binding is complicated and the installation is difficult. The project team adopted Tekla model, optimized detailed nodes, made detailed disclosure with the help of BIM three-dimensional model, made clear the binding sequence and connection mode of steel bars at nodes, installed overweight members separately, and hoisted them with crawler cranes to ensure that the steel structure installation was "as stable as Mount Tai".
How to control the quality of high strength concrete
The project adopts high-strength concrete C60, and the concrete is widely distributed in the core tube shear wall and steel tube column of the tower. In order to ensure the compactness of concrete pouring, the project team tried to mix self-compacting concrete, prepared concrete with slump and expansion that can meet the requirements of self-compacting, and strictly controlled the pouring height of concrete by high throwing method to ensure the quality of structural entities.