Must fabrication errors always be repaired?
No. Because the human element is involved in all phases of structural steel fabrication, material inadvertently may be cut to the wrong length, holes may be misplaced, parts may be located incorrectly or notches or gouges may occur. However, many such errors or deviations need not be altered or repaired and are acceptable without change or penalty to the structure or its end use.Furthermore,some repair work may be more detrimental than leaving the piece un repaired. In general, the structural engineer of record (SER) should evaluate the deviation and whether it would be detrimental to the end use of the product.
In some cases, repair will be required and can usually be made so that the member will meet all performance criteria. Corrective measures to meet the requirements of shop drawings and specifications may generally be made by the fabricator during the normal course of fabrication, using qualified personnel and procedures that meet AISC and AWS specifications. Such action is considered to be a part of the fabricator’s quality control program and should not require either notification of, or approval from, the owner or SER.However, in cases where major work is involved (cutting or removal of welded members from a welded assembly, modification of design, deviation from critical dimensions,etc.), the SER should be consulted and a plan of corrective action agreed upon.
What is BIM?
A Building Information Model as defined by buildingSMART® is a “digital representation of the physical and functional characteristics of a facility. As such, it serves as a shared knowledge resource for information about a facility forming a reliable basis for decisions during its life-cycle from inception onward.”
Shared data and collaboration by different stakeholders are basic premises of BIM. Collaboration and sharing of data is accomplished through interoperability across a variety of platforms. Sharing of data allows for coordination of not just 3D building elements, but scheduling and maintenance data as well.
How does Structural Steel fit into the BIM picture?
Structural steel has a unique position in the BIM world; The Structural Steel industry has been using BIM-capable tools such as 3D modeling and detailing systems since before the term BIM was even in common use. The structural steel model however, represents only one set of data required for constructing a whole building. The models produced by steel detailers and fabricators are essentially only a partial BIM. Detailers and fabricators have been using these tools for years simply out of necessity; it reduces costs, increases efficiency, reduces errors and accelerates schedules. Even when they can’t share their models, it still makes sense to use this technology alone.