# 📐 L2 Spec — Timoshenko Beam — shear-deformation thick-beam Mismatch-Only Spec
**ID:** `L2-209-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-209`](/artifact/l1/L1-209)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.48 · **Delta tier:** 5
> **⛓ On-chain block:** 41554013
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| Snr db | dB | 0 – 40 |
| Ei error | — | 0.0 – 0.1 |
| Ga error | — | 0.0 – 0.1 |
| Bc error | — | 0.0 – 0.2 |
| N sensors | — | 2 – 256 |
| N elements | — | 5 – 10000 |
| K shear error | — | 0.0 – 0.1 |
## 2. Tolerance (ε)
**Type:** `fn`
```
21.0 + 0.3*SNR_dB - 20.0*k_shear_error - 30.0*EI_error - 20.0*GA_error - 10.0*bc_error
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.48 |
| Delta tier | 5 |
## 4. Fingerprint
`0ed79f711295ae39eef4191a1a8f8744e0afc7ed5b0746cb2c8fb43c73326f72`
## 5. On-chain Registration
- **Chain hash:** `0x587f7b6b6705d98e0dfbed3347e547ebf37a0d7e9586e9f66a5e554d87fda7c4`
- **Chain tx hash:** `0x6178c140805f8d4a3fc78577cb5b12409d99746a0fc9892b13c43b8b6ece8959`
- **Chain block:** `41554013`
---
## File Mapping
This bundle consists of: `L2-209-001.md`, `L2-209-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-209-001.md` | Source of truth — edit this | Human or LLM |
| `L2-209-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |
**Prompt for your LLM after editing this Markdown:**
> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.
_This Markdown was auto-synthesized from the catalog row for `L2-209-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._