AS 1538-1988

1 - AS 1538-1988 COLD-FORMED STEEL STRUCTURES CODE
4 - PREFACE
5 - CONTENTS
6 - SECTION 1. SCOPE AND GENERAL
6 - 1.1 SCOPE.
6 - 1.2 NEW MATERIALS OR METHODS.
6 - 1.3 REFERENCED DOCUMENTS.
6 - 1.4 DEFINITIONS.
7 - 1.5 NOTATION.
11 - 1.6 DESIGN AND SUPERVISION.
11 - 1.7 MATERIALS.
11 - 1.7.1 Structural steel.
11 - 1.7.1.1 Standards.
11 - 1.7.1.2 Other steels.
11 - 1.7.1.3 Acceptance of steels.
11 - 1.7.1.4 Unidentified steel.
11 - 1.7.2 Fasteners and electrodes.
11 - 1.7.2.1 Steel bolts,
11 - 1.7.2.2 Electrodes.
11 - 1.7.3 Delivered minimum thickness.
11 - 1.8 CORROSION PROTECTION.
12 - SECTION 2. DESIGN REQUIREMENTS AND SECTION PROPERTIES
12 - 2.1 LOAD COMBINATIONS.
12 - 2.2 DESIGN METHODS.
12 - 2.2.1 Basis of methods.
12 - 2.2.2 Application of AS 1250-1981.
12 - 2.3 OTHER DESIGN CONSIDERATIONS.
12 - 2.4 SECTION PROPERTIES.
12 - 2.4.1 Properties of stiffened and unstiffened compression elements.
12 - 2.4.1.1 General.
13 - 2.4.1.2 Flat elements with low b/t.
13 - 2.4.1.3 Flat elements with medium b/t
13 - 2.4.1.4 Stiffened compression elements with high b/t.
13 - 2.4.2 Stiffeners for compression elements.
13 - 2.4.2.1 Edge stiffeners.
14 - 2.4.2.2 Intermediate stiffeners.
14 - 2.4.2.3 Arched compression elements.
14 - 2.4.3 Maximum permissible flat-width ratio.
15 - 2.4.4 Maximum permissible web depth and web stiffener requirements.
15 - 2.4.4.1 Maximum ratio d /t.
15 - 2.4.4.2 Transverse stiffeners for beam webs.
16 - 2.4.5 Unusually short spans resisting concentrated loads.
16 - 2.4.6 Flexural members subjected to positive and negative bending.
16 - 2.4.6.1 General.
16 - 2.4.6.2 Load-carrying capacity.
16 - 2.4.6.3 Deflections.
16 - 2.4.6.4 Limitations.
17 - SECTION 3. MAXIMUM PERMISSIBLE DESIGN STRESSES
17 - 3.1 MAXIMUM PERMISSIBLE DESIGN STRESS.
17 - 3.1.1 General.
17 - 3.1.2 Yield stress
17 - 3.1.3 Cold-forming.
17 - 3.1.3.1 General.
17 - 3.1.3.2 Methods and limitations.
18 - 3.2 INELASTIC RESERVE CAPACITY OF FLEXURAL MEMBERS.
18 - 3.3 LATERALLY UNBRACED AND INTERMEDIATELY BRACED BEAMS.
18 - 3.3.1 Scope.
18 - 3.3.2 Maximum permissible stress.
18 - 3.3.3 Elastic critical stress.
18 - 3.3.3.1 Doubly symmetric I- and box-beams and monosymmetric I- and T-beams.
18 - 3.3.3.2 Channel and Z-beams.
19 - 3.3.3.3 Minimum values of C m .
19 - 3.4 MAXIMUM PERMISSIBLE STRESSES IN WEBS OF BEAMS.
19 - 3.4.1 Shear stress in webs.
19 - 3.4.2 Bending stress in webs.
19 - 3.4.2.1 Beams having stiffened compression flanges.
19 - 3.4.2.2 Beams having unstiffened compression flanges.
19 - 3.4.3 Combined bending and shear stress in webs.
19 - 3.5 WEB CRIPPLING OF BEAMS.
19 - 3.5.1 Permissible reactions and concentrated loads.
22 - 3.5.2 Combined bending and web crippling.
22 - 3.6 AXIALLY LOADED COMPRESSION MEMBERS.
22 - 3.6.1 Maximum permissible stress.
22 - 3.6.2 Load factor
22 - 3.6.3 Determination of form factor (Q).
22 - 3.6.4 Determination of elastic buckling stress (Foc ).
22 - 3.6.4.1 Doubly symmetric or point symmetric sections.
23 - 3.6.4.2 Monosymmetric sections.
23 - 3.6.4.3 Asymmetric sections.
23 - 3.6.5 Effective lengths
23 - 3.6.5.1 Flexural buckling.
23 - 3.6.5.2 Torsional buckling.
23 - 3.6.6 Maximum slenderness ratio.
23 - 3.7 COMBINED BENDING AND COMPRESSION.
23 - 3.7.1 Doubly symmetric sections.
24 - 3.7.2 Sections which are prevented from twisting.
24 - 3.7.3 Monosymmetric sections.
24 - 3.7.3.1 Sections bent in a plane of symmetry.
24 - 3.7.3.2 Sections bent about a plane of symmetry.
24 - 3.7.4 Other sections.
24 - 3.7.5 Moment coefficients.
24 - 3.8 CIRCULAR HOLLOW MEMBERS IN COMPRESSION OR BENDING.
24 - 3.9 STRESS IN COMPOUND MEMBERS MADE OF DISSIMILAR STEELS.
25 - SECTION 4. DESIGN OF CONNECTIONS
25 - 4.1 FASTENING SYSTEMS.
25 - 4.2 WELDED CONNECTIONS.
25 - 4.2.1 General.
25 - 4.2.2 Fusion welds.
28 - 4.2.3 Resistance welds.
28 - 4.3 CONNECTING TWO CHANNELS TO FORM AN I-SECTION.
28 - 4.3.1 Maximum permissible longitudinal spacing of connectors.
29 - 4.3.2 Uniform spacing of connections.
29 - 4.4 SPACING OF CONNECTIONS IN COMPRESSION ELEMENTS.
29 - 4.5 BOLTED CONNECTIONS.
29 - 4.5.1 General.
29 - 4.5.2 Holes.
29 - 4.5.3 Tension stress on net section.
30 - 4.5.4 Bearing stress on cold-formed steel in bolted connections.
30 - 4.5.5 Permissible stresses in fasteners.
30 - 4.5.6 Friction joints.
31 - SECTION 5. BRACING REQUIREMENTS
31 - 5.1 WALL STUDS.
31 - 5.2 CHANNELS AND Z-SECTIONS USED AS BEAMS.
31 - 5.2.1 Bracing when one flange is connected.
31 - 5.2.1.1 General.
31 - 5.2.1.2 Type and spacing of braces.
31 - 5.2.2 Bracing when neither flange is braced.
32 - 5.2.3 Maximum permissible stresses.
33 - SECTION 6. TESTING
33 - 6.1 COMPRESSION TESTING.
33 - 6.2 TESTS FOR SPECIAL CASES.
33 - 6.2.1 General.
33 - 6.2.2 Evaluation of tests for determining structural performance.
33 - 6.2.3 Tests for determining mechanical properties of formed sections or flat material.
33 - 6.2.3.1 Tests on the full section.
33 - 6.2.3.2 Tests of flat elements of formed sections.
34 - 6.2.3.3 Compliance and control tests for mechanical properties of virgin steel.
35 - APPENDIX A - SECTION PROPERTIES
35 - A1 SHEAR CENTRE DISTANCE (m), TORSION CONSTANT (J) AND WARPING CONSTANT (Iw ).
35 - A2 MONOSYMMETRY SECTION CONSTANTS.
38 - APPENDIX B - PROTECTION
38 - B1 SCOPE.
38 - B2 PROTECTION AGAINST CORROSION.
38 - B2.1 Members to be protected.
38 - B2.2 Protective coating.
38 - B2.3 Members made from uncoated steel.
38 - B2.4 Members made from coated steel.
38 - B3 PROTECTION DURING TRANSPORT, HANDLING AND STORAGE.
38 - B3.1 General.
38 - B3.2 Transport and handling.
38 - B3.3 Storage.
38 - B4 REPAIRS TO COATINGS.
39 - APPENDIX C - MINIMUM VALUES OF YIELD STRESS AND TENSILE STRENGTH FOR STEELS TO AS 1163, AS 1397, AS 1594 AND AS 1595
40 - APPENDIX D - REFERENCES

Sets out rules for the use of structural members of cold-formed steel. This Standard is intended to be complementary to AS 1250-1981, and includes requirements for material less than 3 mm thick. While the technical requirements of this revision are essentially those of the 1974 edition, a number of significant amendments have been made. These include unstiffened compression elements, provision for web stiffeners, introduction of inelastic reserve capacity of flexural members, elastic critical stress of laterally unbraced beams, permissible bending stresses in web, stiffened and unstiffened flanges, web crippling of beam and axially-loaded compression members.

This Standard specifies requirements for the design and protection of structures or structural members made by cold-forming carbon and low alloy steel strip or sheet. The Standard is intended to supplement AS 1250-1981.

Under Revision See DR 95246