Verification Summary: 51 Test Cases Across Three Modules
calcnote's ACI 318-19 column, beam, and footing engines are each verified against independent authorities: published textbooks, commercial software (spColumn), and first-principles hand calculations. This page consolidates all 51 test cases. The full column verification report (PDF) carries the complete per-case derivations for the column module.
Aggregate verdict
| Module | Test cases | Reference sources | Result |
|---|---|---|---|
| Columns | 15 | spColumn, Wight textbook, hand calc | All PASS |
| Beams | 30 | Independent hand calculations | All PASS |
| Footings | 6 | Independent hand calculations | 5 PASS, 1 INCOMPLETE* |
| Total | 51 | 50 PASS, 1 INCOMPLETE |
Column verification (15 cases)
The column engine is cross-checked against three independent authorities. Agreement with spColumn's published example is within 0.03%; with Wight's textbook examples within 1.17%; with first-principles derivations within 0.02%.
| Reference | Comparison | Agreement |
|---|---|---|
| StructurePoint spColumn v10.00 | 4 control points, 16×16 / 8-#9 | ≤ 0.03% |
| Wight, RC: Mechanics and Design, 7th ed. | Examples 11-1, 11-4, 12-2 | 0.47 to 1.17% |
| First-principles strain compatibility | All interaction-curve anchors | ≤ 0.02% |
Full column verification details (15 cases) →
Beam verification (30 cases)
Every beam design check (flexure, shear, deflection, crack control, T-beam geometry) is exercised by at least one witness test case with pinned intermediate and final values.
| Check | Witness cases | Result |
|---|---|---|
| Flexure (Whitney block, φ, As,min) | W1, W3, W6, W9, phi-transition, T1, T2 | All PASS |
| Shear (Vc, Vs, λs, spacing) | S1, S2, S3 | All PASS |
| Deflection (Ie, long-term) | D1, D2 | All PASS |
| Crack control (bar spacing) | C1, C2 | All PASS |
| T-beam geometry (effective flange width) | T1, T2 | All PASS |
Full beam verification details (30 cases) →
Footing verification (6 cases)
Every footing design check (bearing, flexure, one-way shear, punching shear, development length, interface bearing) is exercised by at least one witness test case with pinned intermediate and final values.
| Check | Witness cases | Result |
|---|---|---|
| Bearing pressure (§13.2.1) | TC-1, TC-3 | All PASS |
| Flexure (§13.2.7.1) | TC-1, TC-3 | All PASS |
| One-way shear (Table 22.5.5.1) | TC-1, TC-3 | All PASS |
| Punching shear (Table 22.6.5.2) | TC-1, TC-3 | All PASS |
| Development length (Eq. 25.4.2.4a) | TC-1, TC-3 | All PASS |
| Interface bearing (§16.3.4.1) | TC-1 | All PASS |
*TC-6 (eccentric loading) is INCOMPLETE: punching shear with moment transfer (γv/Jc stress distribution) is not yet implemented.
Full footing verification details (6 cases) →
Witness detail pages
Nine cases have dedicated HTML pages with the full derivation, intermediate values, and cross-checks:
- TC-1: Wight Example 11-1 (16×16 / 8-#9, four-way comparison)
- TC-2/3: Wight Example 11-4 (operating point)
- TC-11: Wight Example 12-2 (slender column)
- TC-12: StructurePoint circular spiral example
- TC-14: Bending axis rotated column (weak-axis Y)
- TC-15: Biaxial interaction surface
- W1: Beam rectangular flexure
- D1: Beam deflection (Bischoff Ie)
- C1: Beam crack control spacing
Continuous revalidation
All 51 reference cases are encoded as automated regression tests that run against the engine on every code change. A drift beyond the stated tolerances fails the build before it can deploy; the numbers on this page cannot silently rot as the engine evolves.