AS3600 2018 code specific items for beams

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

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 IN 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

8.2.4.2 Determination of kv and ɵv (general method)

8.2.4.3 Determination of kv and ɵv for non-prestressed component (simplified method)

8.2.4.5 Reversal of loads (the users can set Vuc = 0 if desired)

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

8.2.8 Proportioning longitudinal reinforcement

8.2.8.1 General

8.2.8.2 Flexural tension side

8.2.8.3 Flexural compression side

8.5 DEFLECTIONS OF BEAMS

8.5.1 General

8.5.3 Beam deflection by simplified calculation

8.6 CRACK CONTROL OF BEAMS

8.6.2 Crack control for tension and flexure in reinforced beams

8.6.2.2 Crack control without direct calculation of crack widths

8.8 T-BEAMS AND L-BEAMS

8.8.1 General

8.8.2 Effective width of flange for strength and serviceability

SECTION 14 DESIGN FOR EARTHQUAKE ACTIONS

14.5 INTERMEDIATE MOMENT-RESISTING FRAMES (IMFRs)

14.5.2 Beams

14.5.2.1 Longitudinal reinforcement

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 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 the design shear (ie. ϕVus ≥ V*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 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 bending capacity.

Serviceability and deflection results are advisory only. No serviceability or deflection limit checks control the results.

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 6.2.3 - Optional preference to reduce maximum negative bending moment at support.

Clause 8.2.4.5 - A zone setting is provided to set Vuc to be equal to zero, else Vuc will be calculated as per normal code requirements.

Clause 8.2.1.2 - Closed fitments are assumed if torsion is to be considered. Only spacing check is considered.

Clause 8.6.1 - Crack control is advisory only. No crack control limit checks control the results.