The portal steel frame structure is widely used in large buildings, such as industrial plants, warehouses, stadiums, etc., because of…
Steel building installation is one of the essential links of steel structure buildings, and the quality of installation is directly related to the safety and durability of the building. Therefore, a series of precautions must be taken while installing steel structures. Below, we will introduce the precautions for steel structure installation in detail.
Steel building installation process:
Construction layout → Embed bolts in foundation concrete → Steel column installation → Steel beam installation → Purlin, roof panel, and eaves panel installation → Wall panel installation → Steel structure painting.
The construction sequence of the independent foundation is the excavation of the foundation pit → foundation pit finishing →, cushion pouring → bottom plate construction →, beam and column construction, → earth backfilling.
Drain, debris cleaning, and steel bar rust removal should be done well.
Column foot anchor construction process:
Steel bar binding → positioning and laying out → installation and fixing of positioning steel plate → installation of column foot anchor → welding and fixing → anchor thread protection;
After the column foot is in place, micro-expansion grouting material should be used for secondary pouring. The thickness should be at least 50mm to delay the corrosion of the column foot anchor and improve the structure’s durability.
Steel Building Installation for Bracing and Purlin
The bracing should be installed simultaneously with the main structure. After forming a stable spatial system, the adjacent structural components should be installed in sequence to prevent continuous collapse due to instability during installation.
When friction-type high-strength bolts connect beam-column and beam-beam, effective measures should be taken to clean the dirt (floating rust, protective coating, etc.) on the connection end surface to achieve the required surface roughness.
The purlin should be installed from the ridge or eaves position. The remaining parts should be installed sequentially after forming a stable system through (struts + diagonal braces + purlins).
The installation of wall girt should consider the position of door and window frames. The opening should be facing away from the door frame or window frame, or double wall beams should be used.
Before spraying the anti-corrosion and fire-proof coating, the surface of the structural components should be degreased and rusted to ensure adequate bonding between the coating and the base layer. During the spraying process, attention should be paid to controlling the uniformity of the thickness to avoid problems such as missing coating and bubbling.
Attention Issues For Steel Building Installation
1. Strictly control the quality of materials.
The quality of materials used when installing steel buildings is essential and must be strictly controlled. Check whether the variety, model, specification, etc., meet the design requirements, and randomly sample the materials for retesting.
They can be used only after the retest is qualified. You can choose matching welding rods, welding wires, and flux according to the steel grade, but all must have certificates.
2. Strictly control the quality of personnel.
When installing steel structures, in addition to paying attention to the quality of materials, you must also pay attention to the quality of the installers.
They must be equipped with technical teacher qualifications. Welding, rivets, and other connections are generally used for steel building installation.
Particular types of work, such as welders and crane operators, must be strictly tested to ensure the operating system’s safety. At the same time, construction personnel’s certificates must be tested to see whether the issuing unit issues them and whether their service life has expired.
3. Pay attention to the connection of steel structures
During the installation of steel building, you must also pay attention to the connection. The components or parts used are all made of steel.
Attention should be paid to the connection quality during installation because if this aspect is not well controlled, it will directly affect the safety of the overall economic structure. It is essential to know the standard connection method selection and connection method, and its reasonable design is a critical part of the steel building installation.
4. Positioning measurement
According to the steel structure installation project planning materials, the horizontal elevation of the root, axis, and column distance should be re-measured.
The cross lines of the vertical and horizontal axes displayed on the top surface of the pipeline are used as the positioning reference for the equipment’s main column.
5. Column installation
To eliminate the influence of the error in producing the column length on the column height, measuring the cross-section of the theoretical height one meter downward before hoisting and displaying prominent symbols as the reference for adjusting the bracket’s height is necessary.
The top surface of the column bottom plate coincides with the cross line of the longitudinal and transverse axes passing through the column base.
The column’s height should be calibrated according to the symbol at its theoretical height, and then it should be laid firmly with a pad to fix the anchor bolts. Use a table theodolite to calibrate the pillars’ verticality in the two-axis directions.
After reaching the request, tighten the bolts with double nuts. For columns with a single unstable structure, temporary protection measures can be taken by adding wind cables.
6. Crane beam installation
Check it before installing the crane beam. It can be manufactured and installed only when the deformation is not excessive.
The crane beam single-piece hoisting should be timely engaged with the corbel with bolts, the connecting plate between the connecting beam and the column should be adjusted with the level, and the light of the theodolite, and the screws should be tightened after meeting the requirements.
7. Roof beam installation
Before the roof beam is assembled on the floor, the assembly must be observed, the component must not be deformed, the high-strength bolt must not have debris such as mud and sand on the impact surface, and the collision surface must be judged flat and dry.
When assembling, sleepers support the assembly, and wooden strips support both sides to improve stability.
The roof beam should be assembled in units between two columns, and the unit should be checked after assembly. After the adjustment inspection reaches the request, the high-strength bolts are tightened.
8. Accessory installation
The roof purlin and wall purlin installation are carried out together. Before using the purlin equipment, check the component’s deformation state, and if there is an over-limit, please deal with it. Remove debris such as oil and sediment from the component’s surface together.
After cross-installation, take multiple purlins as a group and confirm the purlin slope. The straightness of the purlins must be within the allowable deviation range.
9. Re-inspection, adjustment, welding, and repainting
After the hoisting is completed, all components are re-inspected and adjusted, and then on-site welding is performed to repair component paint damage.