by Author: The Steel Structure Business Unit of the Third Construction Co., Ltd.
of China Construction Fifth Engineering Bureau (He Jie, Zhu Qiwu, He Guiyuan, Zeng Qihai) With the improvement of steel structure construction technology, the design of steel structure nodes has become increasingly complex and strangely shaped, and the phenomenon of steel components being overweight, overlength, and ultra wide is common.
The design of giant overweight components has brought higher requirements to lifting equipment, and how to scientifically and economically segment and lift overweight components under the conditions of predetermined lifting equipment is a challenge.
During the implementation of the Changsha Shimao Plaza super high-rise project, the use of steel components in the inevitable segmented positions during production to split the huge overweight components effectively reduces the weight of single hanging components, while ensuring structural quality and construction safety.
Project Overview: Changsha Shimao Plaza is an urban complex composed of super high-rise office buildings and commercial podiums.
There are 4 underground floors, 5 overground podiums, and 75 tower floors, with a total height of 348.5m and a total construction area of approximately 230000 square meters.
The project address is located in the center of the city, and there are other ongoing construction projects on the adjacent north and southeast sides, resulting in extremely small construction sites.
Steel components can only be transported to the construction site through temporary construction roads on the northeast side.
Heavy steel components are stacked in the northeast steel component yard, while the southwest steel components are only used for stacking light components.
A boom tower crane is used for unloading and lifting the steel components.
The structural form of the tower in the layout plan is a steel pipe concrete frame+concrete core tube+extended arm truss system, with the extended arm truss located at 21-24F, 37-39F, and 51-54F respectively.
Conventional cylindrical column diameter of outer frame φ 900～ φ 2500mm, wall thickness 18-32mm.
After the installation of on-site lifting equipment is completed, the wall thickness of the steel pipe column at the position of the bending constraint support and chord connection nodes with the extended arm truss is changed to 55-60mm, and the designed node vertical plate runs through the steel pipe column.
The reinforced section outer frame steel pipe column is segmented into layers and sections, and the weight of the components still exceeds the lifting performance of the existing tower crane, which cannot meet the lifting requirements.
The principle of node splitting: The components after splitting must meet the structural safety requirements of the original design and meet their functional requirements; The disassembled components can meet the requirements of long-distance transportation; The weight of the disassembled components can meet the lifting performance requirements of the lifting equipment on the construction site; After the component is disassembled, try not to increase the number of original welds as much as possible to reduce the safety and quality risks of the structure
.
