ATTEN: Manager Liu
ADD: Longhua Development Zone, Jing County, Hengshui City, Hebei Province
2,1 nodes require more interfaces. Some joints of braced frames are in the shape of "meter". On the one hand, as the joints of the external braced frame, there are eight pairs of joints, all of which are square pipe butt joints and welded joints. On the other hand, as the joints of the internal steel frame beam, there are three pairs of joints, all of which are H-shaped steel butt joints. How about the irregular high-strength screw joints and welding deformation that easily lead to the change of the spatial position of the butt joints? In the process of installation, it is a difficult problem to ensure that multiple pairs of interfaces meet the installation accuracy at the same time. Fig. 6 nodal axis measuring chimney 2.2 internal member arc beam installation technology is difficult. Fig. 7 arc beam closure schematic diagram shows that the diameter of the inner ring is 47 M. Because the external oblique frame and internal force of the upper end of the hole are transmitted through the arc beam of the hole. The steel frames on both sides are installed at a height of 89m, and can not be erected with external vertical support. The construction method of "unsupported connection" is adopted to support the steel frames. It is necessary to ensure the stress requirement of the structure itself in the construction process and the safety of the construction operation, as well as the configuration and design-conformity of the inclined structure after completion of construction.
How to form a stable structure system during installation is a difficult problem for the installation of 23 inner circle upper suspension structure in this project. The installation height is 89m, the transverse span is 28.8m, the cross section of transverse frame beam is H400 *300, and the cross section of suspension column is 600 *600. With the steel column suspended from the inner frame as the main force transfer structure, the lower load is transferred to the outer inclined steel frame through the transfer truss of 25-28 storeys. Because of the high installation height, the external vertical brace can not be erected for installation. For example, according to the structural characteristics, the reverse construction method will lead to a series of problems, such as difficult lifting of steel structure, low installation efficiency, high risk factor of construction operation, etc. How to install the inner circle upper suspension structure and control the installation deformation of the structure within the installation accuracy range is a difficult point in the installation and implementation of this project. 3. The determination of 31 Construction Schemes Fig. 8 The layout of tower crane indicates that considering the structure condition, the actual situation of construction site and the requirement of the total construction period, the overall construction and installation scheme of the main building steel structure is determined as follows: two TC7052 tower cranes are arranged in the main building area, and divided into two construction areas according to the location and working radius of the two tower cranes. Taking the core tube corresponding to the suspension as the center, according to the method of joint installation and part-by-part installation, on the elevation, there are cantilever structures in the outer and inner circles of the skew-braced steel frame of the tower because of the layer-by-layer and from the bottom to the top. When installing, it is necessary to install the stress system of the structure when the alkali actinide junction in the non-cantilever area has been installed for two stories. Requirement.
Installation sequence is as follows: part of the core tube is constructed in five days and one floor, steel structure is constructed in three days and one floor, core tube is constructed five stories faster than steel structure, floor slab is constructed four stories slower than steel structure, and installation of steel structure is carried out at the same time. Outer diagonal bracing frame hoisting is carried out in the order of "column, joint, diagonal bracing". Steel column underneath 25 stories is hoisted by one floor and steel column above 25 stories is hoisted by two stories and one floor. Diagonal bracing is hoisted by "column" between joints and one floor.