# Structural and Beam Calculators

Closed-form beam, section, column, stress, bolt and torsion formulas with typical material values, in SI or US units.

## How to pay

Machine-payable over x402. USDC on: Base (eip155:8453), Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp), Polygon (eip155:137), Arbitrum One (eip155:42161).
No accounts. No API keys. No signup. The paying wallet is the account.

## Machine-readable

- OpenAPI: https://structural-calc.x402tookit.com/openapi.json
- x402 manifest: https://structural-calc.x402tookit.com/.well-known/x402
- Catalog (free): https://structural-calc.x402tookit.com/catalog
- Health (free): https://structural-calc.x402tookit.com/health
- Uptime (free): https://structural-calc.x402tookit.com/uptime

## Endpoints (8)

### GET /beam-deflection — $0.02
Beam max deflection, end slope, reactions and max moment: simply supported or cantilever, point or uniform load. Educational.
Params: support: string, load: string, length: number, E: number, I: number, force?: number, udl?: number, position?: number, S?: number, units?: string
Example: https://structural-calc.x402tookit.com/beam-deflection?support=simply-supported&load=point&length=4000&E=200000&I=80000000&force=20000

### GET /beam-reactions-moments — $0.02
Simply supported beam: reactions, shear and bending moment at a point, and max moment, for point loads plus optional UDL.
Params: length: number, loads?: string, udl?: number, x?: number, units?: string
Example: https://structural-calc.x402tookit.com/beam-reactions-moments?length=10000&loads=3000%3A10000%3B7000%3A20000&x=5000

### GET /bolt-shear-bearing — $0.02
Screening shear and bearing capacity of one bolt from allowable stresses you state; not a code connection check.
Params: boltDiameter: number, allowableShearStress: number, allowableBearingStress: number, plateThickness: number, shearPlanes?: integer, boltCount?: integer, appliedLoad?: number, units?: string
Example: https://structural-calc.x402tookit.com/bolt-shear-bearing?boltDiameter=20&allowableShearStress=150&allowableBearingStress=300&plateThickness=10&shearPlanes=1&appliedLoad=40000

### GET /column-buckling — $0.02
Euler column buckling load with K factors 0.5/0.7/1.0/2.0, slenderness ratio, and a flag when Euler does not apply.
Params: length: number, E: number, I: number, A: number, endCondition?: string, K?: number, yieldStress?: number, units?: string
Example: https://structural-calc.x402tookit.com/column-buckling?length=3000&E=200000&I=8000000&A=2800&endCondition=pinned-pinned&yieldStress=250

### GET /material-properties — $0.02
Typical handbook E, density, strength, Poisson ratio and expansion for steel, aluminium, concrete, timber, copper, titanium.
Params: material: string, units?: string
Example: https://structural-calc.x402tookit.com/material-properties?material=steel

### GET /section-properties — $0.02
Cross-section area, centroid, moment of inertia, section modulus, radius of gyration; parallel axis theorem. Educational.
Params: shape: string, width?: number, height?: number, diameter?: number, innerDiameter?: number, flangeThickness?: number, webThickness?: number, wallThickness?: number, offset?: number, units?: string
Example: https://structural-calc.x402tookit.com/section-properties?shape=i-beam&width=150&height=300&flangeThickness=12&webThickness=8

### GET /stress-strain — $0.02
Axial stress, strain and elongation from load, area, E and length; thermal strain/stress; factor of safety vs yield.
Params: force: number, area: number, length?: number, E?: number, yieldStress?: number, alpha?: number, deltaT?: number, restrained?: boolean, units?: string
Example: https://structural-calc.x402tookit.com/stress-strain?force=100000&area=500&length=2000&E=200000&yieldStress=250

### GET /torsion-shaft — $0.02
Circular shaft torsion: max shear stress tau = T r / J and angle of twist TL/(JG), solid or hollow.
Params: torque: number, diameter: number, innerDiameter?: number, length?: number, G?: number, allowableShear?: number, units?: string
Example: https://structural-calc.x402tookit.com/torsion-shaft?torque=1000000&diameter=50&length=1000&G=80000

## Terms

EDUCATIONAL ESTIMATES ONLY, NOT ENGINEERING DESIGN. Textbook closed-form formulas with idealised assumptions; no code-compliance check, no load factors, no stability or fatigue checks beyond what is stated. Do not use for design, construction or safety decisions; have a licensed engineer verify.