Material properties, shared by every verification. The cross-section is not shared: SIA 263 classifies it from the internal forces, so it belongs to each verification and appears with it.
Checks a solid rectangle under a shear force in its own plane, to SIA 263:2013: the shear area is the whole section and the plastic shear resistance follows from it. Every step shows its formula and the clause it comes from.
You enter fy,k and τy,k from table 1 of your copy of SIA 263, for the grade and the plate thickness, the width b across the shear and the depth h along it, γM1 (clause 4.1.3) and the design shear force VEd as a magnitude. Av is computed from the dimensions, or entered directly.
You get the section properties, the resistance model, the shear resistance and the utilisation with a pass or fail, each with its clause. With the Basic plan, it prints as an A4 calculation note.
A solid rectangle 100 mm wide and 300 mm deep in fy,k = 235 N/mm² and τy,k = 135 N/mm², under VEd = 1,500 kN. These are the module's own results for its worked example, computed when this page was built.
| Input | Value | Ref. |
|---|---|---|
| Characteristic yield strength fy,k | 235 N/mm² | § t.1 |
| Characteristic shear yield strength τy,k | 135 N/mm² | § t.1 |
| Width b | 100 mm | § 5.1.4.1 |
| Depth h | 300 mm | § 5.1.4.1 |
| Shear area Av | Computed from the dimensions | § 5.1.4.2 |
| Resistance factor γM1 | 1.05 | § 4.1.3 |
| Design shear force VEd | 1500 kN | § 5.1.4 |
| Step | Value | Ref. |
|---|---|---|
| Characteristic yield strength | fy,k = 235 N/mm² | § t.1 |
| Characteristic shear yield strengthEntered from table 1, not derived. | τy,k = 135 N/mm² | § t.1 |
| The definition in §1.2.3§1.2.3 defines τy as fy/√3 and table 1 then tabulates values that disagree with it in all eight cells. The table governs.not used | fy,k/√3 = 135.7 N/mm² | § 1.2.3 |
| Resistance factor | γM1 = 1.05 | § 4.1.3 |
| AreaThe sum of the rectangles, exactly. | A = 30,000 mm² | § 5.1.4.2 |
| Second moment of area | Iy = 225,000,000 mm⁴ | § 5.3.4 |
| First moment above the neutral axisWhat (57) needs. Wpl = 2·S for a doubly symmetric section, which is 2,250·10³ mm³ here. | S = 1,125,000 mm³ | |
| Elastic section modulusReported so the section can be recognised against a table row. Not used by this check.not used | Wel = 1,500,000 mm³ | § 5.1.4 |
| Section classNot asked for and not computed: a solid rectangle has no slender plate to classify. Tables 5a and 5b are about a plate buckling locally under its direct stress, and a solid section has no such element — so the class is 1 by construction and the plastic model of (41) is available without condition. | – = 1 | § t.4 |
| Resistance model | PLASTIC. §5.1.4.1 (41) takes the whole shear area at τy,k: the section is stocky enough to yield right through Av before anything buckles, so the stress is taken as uniform over it. | § 5.1.4.1 |
| Step | Value | Ref. |
|---|---|---|
| Shear areaThe whole of the rectangle, §5.1.4.1. | Av = 30,000 mm² | § 5.1.4.2 |
| Shear resistanceVR = τy,k·Av, the plastic model: the stress is taken as uniform over the area at τy,k. | VR = 4,050.0 kN | § (41) |
| Design shear resistanceVRd = VR/γM1 | VRd = 3,857.1 kN | § (41) |
| Shear area required(41) turned round: Av,req = γM1·VEd/τy,k. The sizing form, the one used to CHOOSE a section rather than to check one. | Av,req = 11,667 mm² | § (41) |
| Elastic shear resistance, for comparisonThe force that would bring the ELASTIC peak τ = V·S/(I·t) to τy,k. It is 1.50 times smaller than VR, and that ratio is the redistribution the plastic model of (41) relies on. On a rectangle it is exactly 3/2, the 50 % redistribution.not used | Vel = 2,700.0 kN | § (57) |
| Shear resistance of the sectionVEd ≤ VRd | η = 0.389 · Pass39 % of the capacity used | § (41) |
Verified clause by clause against SIA 263:2013 and against independent calculations used on real projects, before release.
On a rectangle the elastic peak is 1.5 · V/A at the neutral axis, so VR is exactly 3/2 of Vel: equation (41) relies on a 50 % redistribution, against roughly 10 to 20 % on a rolled I. It is what the norm allows.
Equation (42) is written for the web of an I or a U section. A solid rectangle has no such web, so the condition does not apply.
The full calculation is shown on screen, free and without an account. A print-ready A4 calculation note is part of the Basic plan.
Norm: SIA 263:2013 · Page updated: 27 October 2026