The foundation of the steel structure project is constructed by the civil construction team, but when the foundation short column reinforcement is completed, the formwork support is completed and reinforced firmly, the project department then immediately sends professional technicians and construction personnel to carry out the pre-burial work of steel structure bolts. To ensure the quality of the superstructure installation, it must also work closely with the civil construction unit and work together to keep the gate. Pre-embedded must strictly control the position and projection length of the foot bolt, the level and elevation of the foundation support surface, etc.
Bolt pre-buried construction points: for the convenience of the bolt in place, will be used in the factory prefabricated drilling steel mold to assist in the position. When the foundation template is firmly supported, the centerline point (cross-shaped) is measured on the template surface, and the position of the foot bolt is positioned according to the centerline point, then the centerline point on the template surface is adjusted to coincide with the cross line on the drilled steel mold, and the foot bolt is precisely placed in the design position. After the installation of the foot bolt, check the first wire buckle elevation of the lower end of the bolt is in line with the requirements, after passing the bolt will be welded firmly in the reinforcement network. To prevent the threads of the ground bolts from being damaged before or during installation, it is advisable to protect the threads with protective sleeves. And in order to ensure the correct position and elevation of the foundation bolts, watchful observation should be made when the concrete is poured in the civil construction, and if changes are found, the construction personnel should be notified immediately to deal with them in time. When all the foundation anchor bolts are constructed, report to the supervisory company for acceptance of foundation works, and make concealed works acceptance sheet and hand over to relevant units for signing and confirmation. If unqualified parts are found, timely return to repair and rectify to ensure all parts are fully qualified.
Steel Structure Lifting
(I) Preparation for lifting
All foundation anchor bolts of the project will be retested and original records will be made to ensure that the data of all foundation anchor bolts meet the design requirements and the requirements of relevant construction specifications. At the same time, all foundation anchor bolts will be cleaned, oiled, and reviewed for elevation, and all installation bolts will be in place. All overall axes and inter-column dimensions were reviewed.
According to the site road and material stacking situation, set and clean up the hoisting travel route to ensure all roads are unobstructed. Find out the reference points of each steel member separately and make obvious signs.
Before lifting the steel structure, check the incoming components according to the component list, check the quality certificate and design change documents, check and accept the deformation caused by the components in the transportation process, and record them, and correct the problems in time to meet the regulations. For the foundation and pre-buried parts, we should first check and review the axis position, height deviation, flatness and elevation, then pop out the cross center line and cite the elevation, and at the same time, we must obtain the qualified information of foundation acceptance. As it involves both steel structure fabrication and installation, and the relationship between civil construction and steel structure, the measuring tools between them must be unified.
(II) Lifting method
The project adopts two automobile cranes for flowing lifting (according to the actual situation, lifting equipment can be increased), the sub-components and plates are manually suspended and pulled, and the steel column lifting adopts the single machine rotation method for lifting. Each canopy beam is first assembled and corrected on the ground and then lifted, and if necessary, manually lifted to assist in assembling, the steel beam is righted and turned over to start the plate using the two-point starting plate method, and the single machine rotation method is used for lifting. In order to ensure the safety of hoisting and avoid the number of crane stops, the steel structure hoisting of the project was carried out according to the sequence of the route, and the vertical components were hoisted first and the flat components were hoisted later to reduce the accumulated error of the longitudinal length installation of the building.