AS3600-2018 Concrete Column

Name: ULS Rectangular Stress Block
Brand: Community
SKU: bcd417cf-b418-4e64-b82a-2d7f41bb3a7a

A calculation to perform design checks of concrete sections according to AS3600-2018. Circular and rectangular sections with symmetrical reinforcement are implemented.

Community

Maximum LF about X

1 ≤ 1

Maximum LF about Y

1 ≤ 1

Reinforcement Ratio

Design Assumptions

Uniaxial strength is checked about the horizontal X-axis and vertical Y-axis. Rectangular sections also receive the biaxial bending and compression check of AS 3600:2018, Clause 10.6.4, using φ = 0.65.
Columns are assumed braced in each plane of bending. Single curvature is assumed with M₁^*/M₂^* = −1, giving k_m = 1.0 for the braced-column moment magnifier δ_b (Clauses 10.3.1 and 10.4.2).
Section strength uses the rectangular concrete stress block of Clause 10.6.2.
For compression, the moment magnitude about each principal axis is at least 0.05DN^* before magnification, where D is the overall section depth in that plane.
Concrete cover is measured to the face of the longitudinal reinforcement.

Section Preview

svg

Figure:

Concrete Section Preview

Bending about X-axis

Slenderness checks — AS 3600:2018

Braced-column check with M₁^*/M₂^* = −1, following the design assumptions. Under this assumption the short-column limit is 25 (AS 3600:2018, Equation 10.3.1(1)). At L_e/r = 25 the calculation conservatively retains magnification.
For L_e/r > 120, Clause 10.5.1 requires rigorous analysis under Clauses 6.4, 6.5 or 6.6 and design under Clause 10.2.3.

Moment-Axial Capacity Diagram about X-axis

Each point corresponds to a Loads row, using the moment magnitude after the minimum moment 0.05DN^* and member magnification.
The curve is for the governing strength row; point labels show each row's strength check.
Loads at or above the buckling limit are plotted at their unamplified moment and labelled.

Loads and capacity factors about X

Rows match the Loads input and chart.
Design moment includes the minimum moment 0.05DN^* and member magnification.
Buckling shows "Short column" for short columns and the calculated ratio N^*/N_c otherwise.

Bending about Y-axis

Slenderness checks — AS 3600:2018

Braced-column check with M₁^*/M₂^* = −1, following the design assumptions. Under this assumption the short-column limit is 25 (AS 3600:2018, Equation 10.3.1(1)). At L_e/r = 25 the calculation conservatively retains magnification.
For L_e/r > 120, Clause 10.5.1 requires rigorous analysis under Clauses 6.4, 6.5 or 6.6 and design under Clause 10.2.3.

Moment-Axial Capacity Diagram about Y-axis

Each point corresponds to a Loads row, using the moment magnitude after the minimum moment 0.05DN^* and member magnification.
The curve is for the governing strength row; point labels show each row's strength check.
Loads at or above the buckling limit are plotted at their unamplified moment and labelled.

Loads and capacity factors about Y

Rows match the Loads input and chart.
Design moment includes the minimum moment 0.05DN^* and member magnification.
Buckling shows "Short column" for short columns and the calculated ratio N^*/N_c otherwise.

Biaxial bending and compression — Clause 10.6.4

Equation 10.6.4 uses φ = 0.65 and capacities at the same design axial force. Interaction at or below 1 passes this check.
Design moments include the minimum moment 0.05DN^* and directional member magnification.
Rows outside the rectangular compression method are explicitly identified. A summary card is shown only when every row has a finite applicable result.

Validation against RAPT 01/11/2026

Verification Method:Diagram comparison

Verified by:DZ

Verification date:01/11/2026

Number of Checks:20

Validation against Inducta RCC and RAPT 17/07/2025

Verification Method:Comparison of diagram points, buckling loads, moment amplification

Verified by:DZ

Verification date:17/07/2025

Number of Checks:12