AISC ASD 1989

AISC ASD 1989 - an American national standard "Specification for Structural Steel Buildings" Allowable Stress Design and Plastic Design, released in June 1, 1989.

AISC ASD 89

This Standard implements checks for the design of members for tension, compression, bending, shear and combined. Checks are performed for I-beams, Channels, Tee, Circular and Rectangular tubes, Circular and rectangular bars.

To add AISC ASD 89 standard execute StandardAISC ASD 89 (9th, Jul 1989) from the main menu. Alternatively, use the Standard context menu:

Standard AISC ASD 89

To see what elements are not verified for all checks or bending checks according to AISC ASD 1989 press Preview Not Supported.

Press Button_set_section_build_type to set Section Build Type (rolled or built-up).

Standard AISC ASD 89

Lateral-torsional buckling modification factor (Cb) can be calculated based on moment diagram of beam member or defined manually. By default user defined option is used and Cb is set to 1 (conservative):

Standard AISC ASD 89

Standard_AISC_ASD_89_calculate_Cb_formula

Where M1 is the smaller and M2 the larger bending moment at the ends of the unbraced length, taken about the strong axis of the member.

Press to set Cb manually.

By default clear distance between transverse stiffeners are set to torsional member length. (It means there are no transverse stiffeners). Stiffener distance is used to calculate allowable shear stress:

Standard AISC ASD 89

According to the calculation procedure, Beam Length for Y and Z direction is required. Data from Beam Member Finders is used automatically:

API_beam_member_finder

If beam members are not recognized press .

The formulas of AISC ASD 89 standard use Yield Stress from materials. It is important to set this value for each material.

If count > 0 then press to edit Yield Stress:

It is possible to take into account second order effects (see explanation in AISC ASD 89 , Appendix 8):

Standard_AISC_ASD_89_appendix8

When all settings are defined, press OK to create standard.

Standard_AISC_ASD_89_crreate

The standard contains 13 checks: 1 - beam characteristics, 2-7 - calculation dimensions and factors for shapes, 8-10 - classification, axial and bending strength checks, 11 - Tension and Compression check, 12 - Shear Check, 13 - Bending Check, 14 - Geometry checks, 15 - utilization factors for shear and combined axial with bending checks.

To verify the model create a table for Overall Check:

Standard_AISC_ASD_89_overall_check

All Checks have Utilization Factor parameter = (Force, Moment, etc.) / Design Strength. It should be below one (<1) then the check passes.

The value 12345678 is used when the calculations cannot be performed due to geometrical limitations or calculations are out of scope.