Sections considered

B. DESIGN REQUIREMENTS

B3. Design Basis

1. Design for Strength Using Load and Resistance Factor Design (LRFD)

2. Design for Strength Using Allowable Strength Design (ASD)

B4. Member Properties

1. Classification of Sections for Local Buckling

1a. Unstiffened Elements

1b. Stiffened Elements

3. Gross and Net Area Determination

3a. Gross Area

3b. Net Area

D. DESIGN OF MEMBERS FOR TENSION

D2. Tensile Strength

D3. Effective Net Area

E. DESIGN OF MEMBERS FOR COMPRESSION

E1. General Provisions

E2. Effective Length

E3. Flexural Buckling of Members without Slender Elements

E4. Torsional and Flexural-Torsional Buckling of Single Angles and Members Without Slender Elements

Only E4.(a), E4.(b) and E4.(c) are used

E5. Single Angle Compression Members

E7. Members with Slender Elements

1. Slender Element Members Excluding Round HSS

2. Round HSS

F. DESIGN OF MEMBERS FOR FLEXURE

F1. General Provisions

F2. Doubly Symmetric Compact I-Shaped Members and Channels Bent About Their Major Axis

1. Yielding

2. Lateral-Torsional Buckling

F3. Doubly Symmetric I-Shaped Members With Compact Webs and Noncompact or Slender Flanges Bent About Their Major Axis

1. Lateral-Torsional Buckling

2. Compression Flange Local Buckling

F4. Other I-Shaped Members With Compact or Noncompact Webs Bent About Their Major Axis

1. Compression Flange Yielding

2. Lateral-Torsional Buckling

3. Compression Flange Local Buckling

4. Tension Flange Yielding

F5. Doubly Symmetric and Singly Symmetric I-Shaped Members With Slender Webs Bent About Their Major Axis

1. Compression Flange Yielding

2. Lateral-Torsional Buckling

3. Compression Flange Local Buckling

4. Tension Flange Yielding

F6. I-Shaped Members and Channels Bent About Their Minor Axis

1. Yielding

2. Flange Local Buckling

F7. Square and Rectangular HSS and Box Members

1. Yielding

2. Flange Local Buckling

3. Web Local Buckling

4. Lateral-Torsional Buckling

F8. Round HSS

1. Yielding

2. Local Buckling

F9. Tees and Double Angles Loaded in the Plane of Symmetry

1. Yielding

2. Lateral-Torsional Buckling

3. Flange Local Buckling of Tees and Double Angle Legs

4. Local Buckling of Tee Stems and Double Angle Leg Webs in Flexural Compression

F10. Single Angles

1. Yielding

2. Lateral-Torsional Buckling

3. Leg Local Buckling

F11. Rectangular Bars and Rounds

1. Yielding

2. Lateral-Torsional Buckling

F12. Unsymmetrical Shapes

1. Yielding

2. Lateral-Torsional Buckling

3. Local Buckling

F13. Proportions of Beams and Girders

1. Strength Reductions for Members With Holes in the Tension Flange

2. Proportioning Limits for I-Shaped Members

G. DESIGN OF MEMBERS FOR SHEAR

G1. General Provisions

G2. I-Shaped Members and Channels

1. Shear Strength of Webs without Tension Field Action

G3. Single Angles and Tees

G4. Rectangular HSS, Box-Shaped Sections and Other Singly and Doubly Symmetric Sections

G5. Round HSS

G6. Weak Axis Shear in Doubly Symmetric and Singly Symmetric Shapes

H. DESIGN OF MEMBERS FOR COMBINED FORCES AND TORSION

H1. Doubly and Singly Symmetric Members Subject to Flexure and Axial Force

1. Doubly and Singly Symmetric Members Subject to Flexure and Compression

2. Doubly and Singly Symmetric Members Subject to Flexure and Tension

3. Doubly Symmetric Rolled Compact Members Subject to Single Axis Flexure and Compression

H2. Unsymmetric and Other Members Subject to Flexure and Axial Force

H3. Members Subject to Torsion and Combined Torsion, Flexure, Shear and/or Axial force

1. Round and Rectangular HSS Subject to Torsion

2. HSS Subject to Combined Torsion, Shear, Flexure and Axial Force

3. Non-HSS Members Subject to Torsion and Combined Stress

H4. Rupture of Flanges With Holes Subject to Tension

Limit state equations used

D. DESIGN OF MEMBERS FOR TENSION

D2-1 Pg 16.1-32 - section, member

D2-2 Pg 16.1-33 - section, member

E. DESIGN OF MEMBERS FOR COMPRESSION

E3-1 Pg 16.1-40 - member

E4-1 Pg 16.1-41 - member

E7-1 Pg 16.1-48 - member

F, DESIGN OF MEMBERS FOR FLEXURE

F2-1 Pg 16.1-53 - section, member

F2-2 Pg 16.1-53 - member

F2-3 Pg 16.1-53 - member

F3-1 Pg 16.1-55 - section, member

F3-2 Pg 16.1-55 - section, member

F4-1 Pg 16.1-56 - section, member

F4-2 Pg 16.1-56 - member

F4-3 Pg 16.1-56 - member

F4-13 Pg 16.1-59 - section, member

F4-14 Pg 16.1-59 - section, member

F4-15 Pg 16.1-59 - section, member

F5-1 Pg 16.1-60 - section, member

F5-2 Pg 16.1-60 - member

F5-7 Pg 16.1-61 - section, member

F5-10 Pg 16.1-61 - section, member

F6-1 Pg 16.1-62 - section, member

F6-2 Pg 16.1-62 - section, member

F6-3 Pg 16.1-62 - section, member

F7-1 Pg 16.1-63 - section, member

F7-2 Pg 16.1-63 - section, member

F7-3 Pg 16.1-63 - section, member

F7-6 Pg 16.1-63 - section, member

F7-7 Pg 16.1-64 - section, member

F7-8 Pg 16.1-64 - section, member

F7-9 Pg 16.1-64 - section, member

F8-1 Pg 16.1-65 - section, member

F8-2 Pg 16.1-65 - section, member

F8-3 Pg 16.1-65 - section, member

F9-1 Pg 16.1-65 - section, member

F9-6 Pg 16.1-66 - member

F9-7 Pg 16.1-66 - member

F9-13 Pg 16.1-67 - member

F9-14 Pg 16.1-67 - section, member

F9-15 Pg 16.1-67 - section, member

F9-16 Pg 16.1-67 - section, member

F10-1 Pg 16.1-69 - section, member

F10-2 Pg 16.1-69 - member

F10-3 Pg 16.1-69 - member

F10-6 Pg 16.1-70 - section, member

F10-7 Pg 16.1-70 - section, member

F11-1 Pg 16.1-71 - section, member

F11-2 Pg 16.1-71 - member

F11-3 Pg 16.1-71 - member

F11-4 Pg 16.1-71 - member

F12-1 Pg 16.1-71 - section, member

F13-1 Pg 16.1-72 - section, member

G. DESIGN OF MEMBERS FOR SHEAR

G2-1 Pg 16.1-75 - section, member, shear

G3-1 Pg 16.1-80 - section, member, shear

G4-1 Pg 16.1-80 - section, member, shear

G5-1 Pg 16.1-81 - section, member, shear

G6-1 Pg 16.1-81 - section, member, shear

H. DESIGN OF MEMBERS FOR COMBINED FORCES AND TORSION

H1-1a Pg 16.1-82 - section, member

H1-1b Pg 16.1-82 - section, member

H1-3 Pg 16.1-84 - member

H2-1 Pg 16.1-84 - section, member

H3-1 Pg 16.1-85 - section, member

H3-6 Pg 16.1-86 - section, member

H4-1 Pg 16.1-87 - section

Assumptions

GENERAL

The root radius for square and rectangular tubes is taken as the inside radius.

Flange bolt holes equally divided between flanges.

Web bolt holes equally divided between webs where applicable.

If the design calculates a high Ultimate Load Factor then a default failure equation (Yield about xx axis) will be returned.

Warning - If a value has exceeded a limit related to a warning, the value is NOT adjusted to be within that limit, its actual value is used in the calculation.

Section B4.2 Design Wall Thickness for HSS

Some steel manufacturers produce HSS sections
with a wall thickness at the very low end of what the specifications allow.
To account for this, the US section libraries supplied with SPACE GASS
12.27 and later include adjustments to the HSS section properties (depending
on the type of HSS section) and no extra adjustments are made to their
properties during an AISC 360 design or check. In SPACE GASS 12.26 and
earlier, the US section libraries contained non-adjusted properties for
HSS sections and so to allow for this their wall thickness was multiplied
by 0.93 during an AISC 360 design or check. *It is therefore important
that you match the version of the US library with the same version of
SPACE GASS, otherwise unsafe designs of HSS sections could result. It
is also important that you don't use HSS sections from SPACE GASS 12.26
and earlier with other non-US design codes.*

Section B4.3b Net Area

1/16" or 2 mm allowance for hole diameter already assumed to be allowed for in the design data input.

No allowance for chain holes made.

Chapter D Design of Members for Tension

Pin connected members not checked.

Block shear strength not checked.

Eyebars not checked.

Section D3 Effective Net Area

A number of factors are unknown ie the length of the connection, number of bolts in line and the type of the weld used. The user has the choice to leave U as 1.0 via the U flag or turn it on and use the conservative approach as detailed in the Commentary Page 16.1-250 where the net area of the connected elements are used as Ae. A U value is returned to indicate the reduction from the net area ie U = Ae/An.

Circular, square or rectangular solid sections plus circular tubes use a worst case assumption of U = 0.75.

Section E4 Torsional and Flexural-Torsional Buckling of Single Angles and Members Without Slender Elements

Section E4.(d),(e),(f) - Lateral bracing offset not considered.

Section E5 Single Angle Compression members

Section E5.(a) and E5.(b) used - group length used as they are individual members or web members.

Section F

Outstands on box girders treated as tee flanges.

No allowance made for loads placed above or below the centroid.

No allowance for cantilevers in calculation of Cb.

Section F7.3 Box Sections

Box sections with slender web and slender flange will return a zero web local buckling capacity.

Section F10 Single Angles

Bending about principal axis only.

Section F13.2 Proportions limits for I shaped members

Warning given if limits exceeded, calculations still done even though limits have been exceeded.

Section G

No reduction in shear areas for bolt holes.

No web transverse stiffeners assumed.

No shear tension field action is considered (Sect G2.2).

Solid circle shear done same as CHS with wall thickness equal to radius.

Section G3 Single Angles

Star shapes have double shear capacity of equivalent single angle.

Section G4 Rectangular HSS and Box shaped members

Box sections with different thickness flanges and possibly outstands, the element that produces the worst Cv2 value is used as the controlling Cv and the sum of all of the contributing shear elements is used for Aw.

If there is a flange outstand on the box girder these are treated like a T stem kv = 1.2.

Section H1.3

Applied if section is rolled compact in flexure about major axis (axial class ignored).

Section H3.2

If Pr, Mrx and Mry are zero, the shear and torsion interaction is not squared (refer AISC360 Commentary Section H3.2).