The steel frame construction process involves installing steel components into a frame. Lifting and positioning components and then joining them together are all part of the process. Bolting is the most common method. However, site welding is also employed on occasion. Before bolting together the steel structure and handing it over to the main contractor, the constructed frame must be aligned.
Pre-engineered steel buildings have revolutionized the construction industry, and it is a uniform approach where every step is connected. Let’s discuss the steel frame construction process in detail:
Repetition and standardization are two design considerations that contribute to buildability. The recurrence of the same structure type (e.g., the portal shed) and common/standard connection features are two elements of standardization. Tolerance is another point of discussion. Extra controls and perhaps specially-engineered features will be required if “tight” tolerances are required (i.e., tighter than those defined in the National Structural Steelwork Specification – NSSS).
Braced frames or continuous frames are the main options here.
The choice of floor system for multi-story frames will impact the erection sequence since it determines the stability of the partially constructed building.
The piece count is the most crucial factor when planning an erection. An average of 39 items were lifted and placed per hook every shift, with a peak of 60. With a single hook and component weights average of approximately 500 kg, an erection rate of over 100 tonnes per week is achieved, resulting in the release of over 1200 square meters of the deck each week. This is a somewhat hefty component weight for a medium-rise structure, although the area objective is determined by piece count rather than weight. These calculations play an important role in designing the steel frame construction process. The number of pieces built is determined by the crane used and its availability for steel erection rather than other types of buildings.
Erection of pre-engineered steel buildings comprises mainly four tasks:
How the frame is to be attached to its supports is the fundamental structural interface that affects steel erection. Showing bolts cast-in-place with lateral adjustability are often used in Calgary and other areas. Cast-in-place bolts have the benefit of being able to contribute to the steel superstructure’s stability right away – assuming proper packing and wedging. The foundation contractor, not the steel erector, is primarily responsible for the problem of casting in bolts without adjustment.
Attachment points and penetrations are frequent non-structural interfaces in steel-framed structures. The process includes the following things:
The fit-up between the constructed steelwork and components that need strict tolerances is the most common source of trouble during erection. Lift installations, “high-tech” wall cladding panels, and façade glazing are all common examples.
Bolting site connections are preferable to site welding because it is speedier, less sensitive to bad weather, and have fewer access and inspection requirements.
Property class 4.6 and 8.8 non-preloaded bolts to BS EN 15048 are often used in 2 mm clearance holes in structural bolting procedures (for buildings). M20 8.8 completely threaded bolts, the recommended solution, are widely accessible. Bolts with property class 4.6 are often used only for fastening lightweight components like purlins or sheeting rails when 12 mm or 16 mm bolts can be used instead.
Early design decisions made long before erection often considerably impact the capacity to safely, rapidly, and inexpensively accomplish these pre-engineered steel buildings’ preparation and erection procedures. A project that runs smoothly will benefit from good site coordination. Steel shipping, unloading, and erection require adequate access from the steelwork contractor, on-site and on nearby or adjacent access roads. A single look at the steel structure detail section will make you realize the importance of an expert construction company.