As early as the engineering design stage, Qingdao Metro Line 6 took the lead in organizing and setting up a special scientific research team, invited a number of academicians of the Chinese Academy of engineering and authoritative experts in the industry to demonstrate and guide, comprehensively carried out technical innovation and optimization, realized the all-round assembly of beams, slabs, columns and walls, overcome the difficulties of small metro construction site, high waterproof requirements for underground structures, large load on the top of stations, and formed a complete set of construction technical standards, Lay a solid foundation for the prefabrication and assembly of subsequent stations.

Qingdao Metro Line 6 has also “customized” construction equipment for precast stations.

Compared with the traditional cast-in-place station construction method, a standard all-round precast station can reduce labor by 80%, save about 800 tons of steel and 800 cubic meters of wood, reduce 60% of construction waste and reduce 20% of carbon emissions.

The first phase of the line is 30.8km long, all of which are underground lines.

[produced by Qingdao Radio & TV • Lanjing] on the morning of April 27, with the fastening of the last bolt, the assembly of the main structure of keloshi station of Qingdao Metro Line 6, the first all-round precast metro station in China, was successfully completed.

Compared with the traditional process, all kinds of components of the omni-directional precast metro station are produced and processed in a special prefabrication plant, which is not limited by the site, climate, materials and other conditions of the construction site.

Qingdao Metro Line 6 is located in the West Coast new area of Qingdao.

The prefabrication production can be carried out synchronously in the foundation pit excavation stage.

Qingdao Metro Line 6 has thoroughly practiced the concept of green development, deeply explored the engineering potential, optimized the design scheme, established a special research team, carried out prefabrication and assembly research, and comprehensively promoted the application of prefabrication and assembly technology in metro construction.

The prefabrication plant comprehensively uses three-dimensional laser scanning technology and BIM Technology to quickly obtain the three-dimensional coordinates, textures and other information of component surface points.

Turnover materials such as formwork and scaffold are no longer used at the construction site, which avoids cutting and welding at the site, and helps to bid farewell to the traditional image of “dirty, disordered and poor” at the construction site.

Solid Lifting Socket

The heaviest base plate component is more than 20 meters long and weighs 113 tons.

17 precast production enterprises have served line 6, with an estimated output value of 1.3 billion yuan..

There are 21 stations, 6 of which are precast stations.

Up to now, through technical research and development, line 6 has obtained a total of 18 patented technologies for the construction of various precast stations, forming a complete set of all-round precast station prefabrication and assembly technologies with independent intellectual property rights.

The precast metro station, an industry technology innovation project with 18 patents, is a new type of precast building, that is, the station components are intensively produced in the prefabrication plant, and then the precast components are assembled in sequence like “building blocks” at the construction site.

After the assembly conditions are available on site, the intelligent gantry crane is used for lifting and assembly.

At the same time, BIM forward design, three-dimensional modeling, construction animation simulation and other technical means are widely used in construction drawing design, scheme research, site planning, process disclosure, progress management, etc.

In order to ensure the quality of subway structure, precast stations require very high precision in prefabrication and assembly of components.

Through cloud computing, it quickly constructs a solid three-dimensional model, which is compared with the design model to ensure the production, processing and assembly quality of precast components.

The prefabrication plant has good construction conditions and high degree of specialization of workers, which can effectively improve the structural construction quality.

It took more than 30 staff members six months to finally complete the assembly of the country’s first fully assembled subway station with a total weight of 23000 tons.

It has independently developed a full set of tooling and equipment such as “160t intelligent gantry crane + integral separated trolley” with multiple intelligent functions, such as rotation, precise automatic positioning, anti swing, attitude fine adjustment and deviation correction, which has solved the problems of prefabrication, turnover and hoisting of large components, and effectively ensured the assembly accuracy of components and the hoisting safety of large components.

The workers only need to guide and connect the “building blocks” in place, and the traditional “formwork plastering, covering and maintenance” is no longer required.

Keluoshi station is a standard station with two floors underground, with a total of 512 assembly components.

This requires that the “building blocks” should be done well and accurately.

Since the commencement of construction, prefabrication and assembly technology has been adopted in more than 10 aspects, such as enclosure, access road, plank house, box culvert, power pipe, segment, etc.

At the construction site of keluoshi station of Qingdao Metro Line 6, the most conspicuous are the precast components of the station with super large volume and weight.

Line 6 also innovatively designed the flow production and steam curing process of precast components, so that the precast components can be transported by means of automatic flow operation and roller table, and the technology of mold follow-up, station fixation and oil cylinder jacking transmission is adopted, so that the plant design, logistics moving line and flow production line planning and layout of large precast components are reasonable, and the automatic, information-based and intelligent production of component prefabrication is realized.

Since the end of October last year, more than 30 on-site workers have built this “giant building block” here.

The safety risk is effectively reduced, and the operation time on the assembly site is reduced by about 70%, saving the construction period of 4-6 months.

For example, BIM 3D simulation collision is used to demonstrate the whole process of assembly construction, identify and solve existing problems in advance, and through process simulation animation, the on-site technicians and workers can more intuitively understand the key points of construction technology, improve the quality of technical disclosure, ensure that the construction and installation accuracy is controlled within 2mm, and fully ensure the high-quality construction of the new technology of omni-directional precast station.

It has been rated as “urban rail transit technology innovation and promotion project” by the Chinese Society of civil engineering, and has contributed to accelerating the transformation of subway construction from a labor-intensive industry to a green and technology intensive industry.