Inputs
Enter current conditions and track details, then submit.
Result appears above this form after submit.
Example data table
Sample scenarios to illustrate how inputs influence risk. Replace with measured values for real decisions.
| Scenario | Rail Temp (°C) | Neutral (°C) | Rail | Unbraced (m) | Ballast | Alignment | Radius (m) | Months | Expected outcome |
|---|---|---|---|---|---|---|---|---|---|
| Hot tangent, strong restraint | 52 | 35 | 60 kg/m | 10 | Good | Good | 0 | 3 | Typically Low–Moderate |
| Hot curve, fair ballast | 58 | 34 | 60 kg/m | 12 | Fair | Fair | 800 | 9 | Often Moderate–High |
| Very hot curve, weak restraint | 62 | 32 | 50 kg/m | 14 | Poor | Poor | 450 | 18 | Commonly High–Critical |
| Warm day, high-stiffness track | 45 | 35 | 68 kg/m | 10 | Good | Good | 1200 | 6 | Often Low |
| Near-neutral temperature | 34 | 35 | 60 kg/m | 12 | Fair | Good | 0 | 12 | Usually Low |
Formula used
1 Thermal stress from temperature rise:
σ = E · α · ΔT
σ in MPa, E in MPa, α in 1/°C, ΔT in °C.
2 Thermal compressive force:
F = (σ · A) / 1000
A in mm². Result F in kN (screening-level).
3 Buckling capacity proxy (Euler-type):
Pe = (π² · E · I) / L²
I in mm⁴, L in mm. Converted to kN in the tool.
4 Adjustments for restraint and curvature:
Pcr = Pe · (1 + R/200) · fcurve · 0.90
R is estimated lateral restraint (kN). Factors represent fastening, ballast, alignment, and maintenance.
Important: This is a planning-level screening calculator. For final engineering decisions, follow your railway standards, inspections, and approved analysis methods.
How to use this calculator
- Measure or estimate rail temperature and confirm the neutral temperature from records.
- Select the rail profile and enter an unbraced length representative of the segment.
- Choose fastening, ballast condition, and alignment quality as observed on site.
- Enter curve radius (use 0 for tangent) and months since tamping.
- Click Calculate risk. Review category, score, and recommended actions.
- Use Download CSV or Download PDF for reporting.