This is how the steel frame structure of the 25-meter deep foundation pit was born

//This is how the steel frame structure of the 25-meter deep foundation pit was born

This is how the steel frame structure of the 25-meter deep foundation pit was born

The Jifu building consists of four floors of basement, five floors of podium building and 14 floors of tower above ground. The total floor area is 59559.3 square meters, 30625.49 square meters on the ground and 28933.81 square meters under the ground. The main building and skirt room are made of steel frame structure, while the basement is concrete frame structure. The project is expected to be completed in June 2019.

Steel Frame Structure

All-steel construction
Compared with those of other site, Jifu building did not erect scaffolding structure at construction stage, project director said: “The scaffolding main role is operating platform and peripheral. When conventional high-rise reinforced concrete structure construct, every type of workers need certain operating space and ensure the safety protection in place, so you must set up the scaffolding. The superstructure of the jifu building project is all steel frame structure, and the steel frame structure can be quickly hoisted into shape. During the hoisting operation, life rope and horizontal isolation are set up according to the standard requirements, and the protective railings are set up timely, so there is no need to set up the outer scaffold when the safety measures are in place.

Steel Frame Structure
Compared with the traditional reinforced concrete structure, the steel frame structure has the advantages of light weight, high reliability of structure, high degree of mechanization of manufacture and installation, and good seismic performance. And because the components can be manufactured and installed on site, the construction period can be reduced. Because of the reusable steel, and also can greatly reduce construction waste, more green and energy-saving, it is widely adopted and has become the mainstream construction technology.
The steel frame structure of this project has a large lifting capacity, and a total of 6,500 tons of steel structure is adopted. One steel frame structure tower crane is installed in the tower and the podium area respectively. Under the condition of limited site operation conditions, the project department successfully completed all lifting tasks within less than 3 months. Meanwhile, floor pressing steel plate laying and concrete pouring were completed before July 10, indicating that the main structure of jifu building was successfully capped, indicating that the project was about to enter the subsequent construction stage of secondary structure, electro-mechanical installation and curtain wall.

When I first saw the jifu building, I always felt that it was different from other buildings, which was not so neat. Other buildings in the expo area were mostly square and upright, while the jifu building was different. The outer boundary line of the building expanded gradually from bottom to top, and the outer contour of the building was circular. Understand after just know, the project design inspiration comes from the process of two grain of jelly landing and bouncing, architects capture the jelly pop instant rise and float in the sky of electromotive force, and the abstract for the tower and podium building form, embodies the smart building, but also show the uniqueness of this enterprise and vigorous upward momentum.
As a foreign investment, the owner of the building itself has a unique insight. In order to make the inside view of the floor more open, the owner wants the net height inside the floor to be as high as possible, which means that the mechanical and electrical pipeline should be rearranged and optimized, and even the structural parts should be optimized.
In view of the high standard requirements of the owner, the general contracting project department adopts BIM technology to realize the overall control of the project, and examines two-dimensional drawing problems through BIM 3d technology to make complex nodes visible and guide the site construction. At the same time, the comprehensive layout of pipeline was optimized through BIM model collision, and the arrangement of beam and plate of part of steel structure was optimized under the condition of design, which not only met the owner’s requirements on floor net height, but also achieved the purpose of resource saving.

Steel Frame Structure
As a four-storey deep foundation pit with a maximum depth of 25 meters, the foundation pit construction is also one of the major difficulties in the construction of jifu building. Face the complex geological conditions and surrounding environment, project department in accordance with the approved by the expert argumentation of foundation pit engineering special strict construction plan to organize the construction, also by adopting automatic monitoring technology, monitor the surrounding environment, buildings, pipes, Po into common pipe trench, Tibet south road tunnel, confined water as well as the deformation of the retaining structure, ensuring the safety of foundation pit engineering construction has always been controlled.
At the same time, the owner to the basement waterproof effect request is particularly high. In order to improve the overall waterproof effect of the project basement, the external wall of the 700mm thick reinforced concrete basement was specially designed inside the 1000mm thick underground continuous wall. In addition, in order to further improve the waterproof performance, the construction process of the 700mm thick structure wall was reasonably adjusted. Through the consultation of all parties, it was decided not to use the conventional form for pulling screw rods and to replace it with the truss-type single-side formwork system less used in civil buildings.

Because the basement floor height is above 4m and the highest height is up to 7.5m, the lateral pressure of the external wall of this structure is huge. The project department has prepared a special plan and passed the expert demonstration, which further improves the overall waterproof effect of the project basement under the guarantee of safety.
The Jifu building project covers only 7,587.9 square meters, while the foundation pit covers an area of 6,500 square meters. The outer boundary line of the foundation pit is highly overlapping with the building red line. This is the difficulty and challenge that accompany the construction of the project to the current top of the structure until the final completion.
Through the careful construction and management of the project team of the general contracting department of Shanghai construction industry, the jifu building project has won the honorary titles of Shanghai civilized construction site, Shanghai star construction site and Shanghai popular construction site in 2017.

2018-09-28T16:06:51+00:00