Copyright 2025 by Space Gass Pty Ltd
Sections considered
AS3600-2018 Concrete Structures Code (incorporating amendment 1)
SECTION 1 SCOPE AND GENERAL
1.1 SCOPE AND APPLICATION
1.1.2 Application
(a)(i)
SECTION 2 DESIGN PROCEDURES, ACTIONS AND LOADS
2.2 DESIGN FOR STRENGTH
2.2.2 Strength check procedure for use with linear elastic methods of analysis
(ii) Table 2.2.2
2.3 DESIGN FOR SERVICEABILITY (Advisory only)
2.3.2. Deflection
SECTION 3 DESIGN PROPERTIES OF MATERIALS
3.1 PROPERTIES OF CONCRETE
3.1.1 Strength
3.1.1.1 Characteristic compressive strength
(a)
3.1.1.3 Tensile strength
3.1.2 Modulus of elasticity
(c) Table 3.1.2
3.1.4 Stress-strain curve
(a)
3.1.7 Shrinkage (Used for deflection calculation - Advisory only)
3.1.7.1 Calculation of design shrinkage strain
(c)
3.1.7.2 Design shrinkage strain
3.1.8 Creep (Used for deflection calculation - Advisory only)
3.2 PROPERTIES OF REINFORCEMENT
3.2.2 Modulus of elasticity
(a)
SECTION 6 METHODS OF STRUCTURAL ANALYSIS
6.2 LINEAR ELASTIC ANALYSIS
6.2.3 Critical sections for negative moments (optional)
6.2.7 Moment redistribution in reinforced and prestressed members for strength design
SECTION 8 DESIGN OF BEAMS FOR STRENGTH AND SERVICEABILITY
8.1 STRENGTH OF BEAMS ON BENDING
8.1.1 General
8.1.2 Basis of strength calculations
8.1.3 Rectangular stress block
8.1.6 Minimum strength requirements
8.1.6.1 General
8.1.9 Spacing of reinforcement and tendons
8.2 STRENGTH OF BEAMS IN SHEAR (See "Assumptions" below)
8.2.1 General
8.2.1.1 Combined flexure, torsion and shear
8.2.1.2 Consideration of torsion
(b) For solid section
8.2.1.6 Requirements for transverse shear reinforcement
8.2.1.7 Minimum transverse shear reinforcement
8.2.1.9 Effective shear depth
8.2.3 Sectional design of a beam
8.2.3.1 Design shear strength of a beam
8.2.3.2 Maximum transverse shear near a support
8.2.3.3 Shear strength limited by web crushing
8.2.3.4 Combined shear and torsion strength limited by web crushing
(b) Other section
8.2.4 Concrete contribution to shear strength (Vuc)
8.2.4.1 General
8.2.4.3 Determination of kv and ɵv for non-prestressed component (simplified method only)
8.2.5 Transverse shear reinforcement contribution (Vus)
8.2.5.1 General
8.2.5.2 Transverse reinforcement for shear
8.2.5.3 Transverse reinforcement for combined shear and torsion
8.2.5.4 Transverse reinforcement for torsion
8.2.5.5 Minimum torsional reinforcement
8.2.5.6 Torsional resistance
8.2.7 Additional longitudinal tension forces caused by shear
SECTION 10 DESIGN OF COLUMNS FOR STRENGTH AND SERVICEABILITY
10.1 GENERAL
10.1.1 Design Strength
10.1.2 Minimum bending moment
10.1.3 Definition
10.1.3.1 Braced column
10.1.3.2 Short column
10.1.3.3 Slender column
10.2 DESIGN PROCEDURES
10.2.1 Design procedure using linear elastic analysis
10.2.2 Design procedure incorporating secondary bending moments
10.2.4 Design for shear
10.3 DESIGN OF SHORT COLUMNS
10.3.1 General
10.4 DESIGN OF SLENDER COLUMNS
10.4.1 General
10.4.2 Moment magnifier for a braced column
10.4.3 Moment magnifier for an unbraced column
10.4.4 Buckling load
10.5 SLENDERNESS
10.5.1. General
10.5.2. Radius of gyration
10.5.3. Effective length of a column (the user must enter kx and ky)
10.6 STRENGTH OF COLUMNS IN COMBINED BENDING AND COMPRESSION
10.6.2 Strength of cross-sections calculated using the rectangular stress block
10.6.2.2 Squash load
10.6.2.3 Decompression point
10.6.2.4 Transition from decompression point to squash load
10.6.2.5 Transition from decompression point to bending strength
10.6.4 Design for biaxial bending and compression
10.7 REINFORCEMENT REQUIREMENTS FOR COLUMNS
10.7.1 Limitations on longitudinal steel
10.7.2 Functions of fitments
10.7.3 Confinement to the core
10.7.3.1 (a) General requirements
10.7.4 Restraint of longitudinal reinforcement
10.7.4.1 (a) General requirements
10.7.4.3 Diameter and spacing of fitments and helices
Assumptions
The 2018 version of AS3600 uses the compressive strut method in which the shear and torsion is carried by both the transverse reinforcement and the longitudinal reinforcement. This means that extra longitudinal reinforcement for shear and torsion is sometimes required in addition to the reinforcement required for axial force and bending. When operating in "Design mode" the stirrup spacing is initially set so that minimum shear and torsion requirements are satisfied and the stirrup capacity alone is sufficient to resist twice the design shear (ie. ϕVus ≥ 2V*eq with no allowance made for the shear strength of the concrete). Any extra longitudinal reinforcement required for shear and/or torsion is then calculated in accordance with clause 8.2.7 and added to the requirement for axial force and bending. Further checks are then done with the stirrup spacing and longitudinal reinforcement adjusted if necessary to satisfy those checks. When operating in "Check mode" if extra longitudinal reinforcement is required for shear and/or torsion it is calculated in accordance with clause 8.2.7 and the remaining longitudinal reinforcement is used to calculate the axial and bending capacity.
Clause 3.1.1.3 - f'ct.f is taken as 0.6(f'c)^0.5.
Clause 3.1.2 - Ec is taken from Table 3.1.2 for standard f'c values, where f'c is taken from the material properties of the member in the SPACE GASS model. For non-standard f'c values, Ec is taken from the material properties of the member in the SPACE GASS model.
fsy and reinforcement ductility is taken from the SPACE GASS reinforcing bar library. If the section contains a mixture of bars with different fsy and ductility values, the fsy and ductility of the first bar on the bottom layer is used.
Clause 8.2.1.2 - Closed fitments are assumed for columns, the users can also specify number of shear legs in each direction
Clause 8.6.1 - Crack control is advisory only. No crack control limit checks control the results.
Copyright 2025 by Space Gass Pty Ltd