Source: https://guthlabs.ai/docs/instruments/beam-deflection-propped-cantilever/implementation/

instrument implementation / implementation-contract

# Beam Deflection — Propped Cantilever implementation

A source-bound implementation contract for Beam Deflection — Propped Cantilever; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t2-046

**Effect**: Computation or source lookup only

## Input and validation requirements

The specification has an undefined deflection result when E or I is zero and does not provide the required formulas for the advertised point-load P branch. A robust instrument should reject zero stiffness and explicitly reject or separately implement point-load inputs.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "load_type": "full-span UDL",
    "w": 10000,
    "w_unit": "N/m",
    "L": 4,
    "L_unit": "m",
    "E": 200000000000,
    "E_unit": "Pa",
    "I": 0.000008,
    "I_unit": "m^4"
  },
  "expected_outputs": {
    "R_prop": 15000,
    "R_prop_unit": "N",
    "R_fixed": 25000,
    "R_fixed_unit": "N",
    "M_fixed": 20000,
    "M_fixed_unit": "N*m",
    "Mmax": 20000,
    "Mmax_unit": "N*m",
    "delta_max": 0.00864864865,
    "delta_max_unit": "m"
  },
  "working": "R_prop=3wL/8=3×10000×4/8=120000/8=15000 N. R_fixed=wL−R_prop=10000×4−15000=40000−15000=25000 N. |M_fixed|=wL²/8=10000×4²/8=10000×16/8=160000/8=20000 N·m. For this UDL, Mmax=|M_fixed|=20000 N·m. δmax=wL⁴/(185EI)=10000×4⁴/(185×200000000000×0.000008)=10000×256/(185×1600000)=2560000/296000000=0.00864864865 m."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/beam-deflection-propped-cantilever/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/beam-deflection-propped-cantilever/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/beam-deflection-propped-cantilever/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche2/tranche2-results.json`