The first in the country! The assembly of the pile-support system assembly metro station of Qingdao Metro Line 6 is completed!

On December 31, with the precise placement of the last medium plate, the first pile-supported system assembly metro station of Qingdao Metro Line 6 was successfully assembled. Chaoyang Road Station of

Qingdao Metro Line 6 is an underground two-storey island station, which is divided into cast-in-place section and prefabricated section. The cast-in-place section is located at both ends of the station, with a length of 70 meters. The prefabricated section is located in the middle of the station, with a length of 148 meters. There are 74 rings and 410 pieces of assembly components. The heaviest roof component is more than 10 meters long and weighs 67 tons. The total assembly weight is 16,600 tons. The construction of assembled station

with pile-support system is the first case in China, and the station has carried out scientific research and tackling key problems from the aspects of assembly technology, disassembly and replacement of supports, research and development of tooling equipment, and application of BIM technology in the assembly process. It is necessary to overcome a series of major construction problems, such as the cooperative operation between the removal and replacement of the pile-support system and the assembly of large prefabricated components, the assembly trolley crossing the internal support of the pile-support system, the full prefabrication and assembly of structural components such as beams, slabs and columns, and the rotation and turning of the middle slab in a narrow space. Faced with a series of major problems, China Railway Eighth Bureau first proposed the application of ordinary gantry crane + separated integral assembly trolley to realize the assembly and construction technology under the pile-supported system in China, so as to realize the longitudinal walking of the trolley under the influence of the prefabricated central column and longitudinal beam of the assembled station, and automatically cross the steel support in the pile-supported support system; Realize the rotation, turning over, positioning and installation precision adjustment of the prefabricated member in a narrow space. It has developed a number of patents, such as prestressed jacking device, which is suitable for the connection support of the middle plate and side wall of the assembled station, and has independent intellectual property rights. There are 2 invention patents, 1 international patent, 16 utility model patents and 1 first prize of national QC achievement. Compared

with the cast-in-place station of the same scale, prefabricated assembly construction, centralized mass production and prefabrication of components, on-site assembly. The construction period can be shortened by 4-6 months, and the construction period can be shortened by 25% -30%; the number of construction personnel in peak period can be reduced from 160 to 20, and the number of construction personnel can be reduced by 85%; considering comprehensively, the construction cost of a single station can be saved by about 5 million yuan; The amount of temporary timber (formwork support) for construction is saved by about 800 cubic meters; the components are assembled and formed at one time, and the on-site construction waste such as concrete chiseling and concrete waste is reduced by about 50%; the carbon emission is reduced by 4157.9 tons, with a reduction of 20.33%, which is in line with the national double-carbon strategy.

It is reported that assembly and construction technology conforms to the concept of green low-carbon development, represents the future development trend of the industry, and lays a solid foundation for the realization of national carbon peak and carbon neutralization goals. It has broad prospects and important value to improve the quality of entities, reduce structural defects, improve production efficiency, shorten the construction period, save costs, and promote the deep integration of industrialization, informatization and intellectualization in the field of rail transit engineering through factory batch prefabrication. Through the research and application of intelligent gantry crane and separate integral assembly trolley, the key technology of prefabricated assembly construction of open-cut subway station realizes high-precision assembly control, high degree of mechanization, improves construction efficiency, significantly reduces the number of operators, and the tooling equipment can be reused to save costs.