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The program is able to design steel beams that are sometimes used to support wooden members in typical structures.
Design Standard
The program designs steel beams according to the 2009 CSA-S16-14 design standard. Note that this standard is referenced by the National Building Code of Canada, and is the only reference in the NBC to steel structure design.
Member Types
Only beams are modified to allow for steel design. There are no steel columns, joists or wall studs.
Materials
The program implements a subset of W shapes that are listed for beams in the CISC Handbook of Steel Construction..
In Sizer, for steel design, Species is renamed “Strength” and has one selection corresponding to 300 Mpa steel. The designation “Grade” changes to “Shape”, and includes just one – “W”. “Width” and “Depth” are replaced by “Depth” and “Mass”, and includes the choices for nominal depth and mass from the W shapes.
The WoodWorks Database Editor allows for user modifications of the Steel Database file supplied with the program.
Loads Analysis
The load combinations used for shear and bending design are from in NBC table 4.1.3.2 for ultimate limit states (strength) design. Load combinations used for deflection are the generalised load combinations from NBC Commentary 12, with principal load factor equal to one as per Commentary 16.
Load combinations used for permanent and live deflection are these combinations with the appropriate non-permanent and non-live types removed. Permanent load combos use the loads types in Commentary Table A-3 that are permanent; live combos use the loads in the Table A-3 that are classified as variable. Live storage/fluid loads are classified as both.
Design
The program designs for shear, bending and deflection design criteria.
Design for steel beams is for vertical loading only; there are no axial or transverse components. The program does not allow for oblique angle beams and y-axis bending.
The values of Mr, Vr, and I needed for bending, shear, and deflection design are taken from the Beam Selection Tables in the CISC Handbook of Steel Construction using the values of unsupported length Lu input in the Beam Input View to select Mr. It interpolates for intermediate values of Lu .
The program does not include the effect of transverse stiffeners for shear design (S16-01 13. 4 and 14.5)
You have to manually change deflection limits if they are not appropriate for steel. There are no default deflection limits for steel materials.
Bearing design is for the supporting wood member only; neither the compressive strength of the steel contact area (S16-01 13.10) or web yielding (14.3.2) are checked.