Erection

The processes involve lifting and placing components into position, then connecting them together - generally using bolting but sometimes using site welding. The assembled frame needs to be aligned before bolting up is completed. Often the ability to complete these processes safely, quickly and economically is influenced significantly by early decisions made during design long before erection commences. It is important that designers clearly understand the impact that their decisions can have; "buildability" is a valid design objective.

The cost of erection is determined by the speed of erection which is dependent to a large extent on the connection design. Typically it can be 7 to 10% of the total project budget.  Its estimation requires careful consideration of all aspects of erection scheme. A structure may be subjected to temporary loads during its erection, which it will never again be asked to carry. This may happen before all structural members are in place.

Safety is a crucial consideration during steel erection. This is particularly the case as part-erected structures can be vulnerable to collapse, cranes can overturn or drop large components, and also because work on the frame requires erectors to access the structure at heights from which a fall could well be fatal.  Regulations lay down mandatory requirements regarding the provision of equipment and arrangements to minimise the risk of an accident.

The main aim during erection is the preservation of the stability of the structure at all times. Most structures which collapse do so during erection, and these failures are very often due to a lack of understanding on someone's part of what another has assumed about the erection procedure (ie. a communication problem).