D. AS 3600 Beam Design Principles

Design is performed per AS 3600-2001. Steel Strength reduction factors are taken from Table 2.3. Characteristic strength of materials are used based on section 6

Strength of Beams

Beams are designed for flexure, and shear. The main (longitudinal) reinforcement is calculated for both sagging and hogging moments on the basis of the section profile and parameters defined in the Design Brief. Lateral bending can be considered if user selects the option. Compression reinforcement is provided where required.

Flexure design is done based on the rectangular stress block defined in clause 8.1.2.2

γ = [0.85 = 0.007(fc - 28)]

Minimum Strength requirement as per 8.1.4

$A s t b ⋅ d ≥ 0.22 ( D d ) 2 f ′ c f f s f$

Requirements for shear reinforcement Clause 8.2.5

Where V* ≤ φVuc , no shear reinforcement is required , except that where the overall depth of the beam exceeds 750 mm, minimum shear reinforcement shall be provided in accordance with Clause 8.2.8

Where V* > φVu,min . Shear reinforcement shall be provided in accordance with clause 8.2.10

Shear strength limited by web crushing : Maximum shear force resisted by element as per the clause 8.2.6

Vu,max = 0.2 f'cbvd0

Shear Strength of a beam excluding shear reinforcement

Vuc = β1β2β3bvd0(Astfc/bvd0)1/3

Strength of beams in shear 8.2 section