Equivalent Axle Load Calculator
A 100 kN single axle does 2.44141 times the damage of the 80 kN standard axle, by the fourth-power law.
IRC and AASHTO: 80 kN (8.16 t) single axle with dual wheels.
2.44140625
Full answer, then cut to fewer decimals (not rounded):
- 2.44140625
- 2.4414062
- 2.441406
- 2.44140
- 2.4414
- 2.441
- 2.44
- 2.4
- Load ratio W/Ws
- 1.25
Step-by-step solution
- EF = (W/Ws)⁴ = (100/80)⁴ = 2.44140625
Equivalent Axle Load Formula
N = 365 A [(1 + r)ⁿ − 1]/r × D × F
damage factor = (W/80 kN)⁴; N in standard axles (÷10⁶ for msa)
Worked Example
A 100 kN single axle compared with the 80 kN standard axle:
- EF = (W/Ws)⁴ = (100/80)⁴ = 2.44140625
GATE tip
A is the traffic in the year the road opens: project survey traffic forward with (1 + r)^x for the construction period first.
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Frequently asked questions
Why the fourth power?
The AASHO Road Test found pavement damage rises roughly with the fourth power of axle load, so overloaded trucks dominate design traffic.
What lane distribution factor does IRC 37 use?
1.0 for a single lane, 0.75 for a two-lane single carriageway, and 0.6–0.75 per lane for dual carriageways.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures .
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Equivalent Axle Load Calculator. Retrieved October 29, 2026, from https://scientificconverters.com/calculators/equivalent-axle-load-calculator/
IEEE
Scientific Converters, "Equivalent Axle Load Calculator," scientificconverters.com. Accessed: Oct. 29, 2026. [Online]. Available: https://scientificconverters.com/calculators/equivalent-axle-load-calculator/