Use this engineering calculation for a transparent preliminary estimate or independent arithmetic check when geometry, materials, loads, operating conditions, and units are defined consistently.

Axle Passes

Required integer input.

Equivalency Factor

Required number input.

Equivalent single-axle load count from traffic axle repetitions times a supplied equivalency factor; factor must come from a chosen method. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Equivalent Axle Loads

The resulting equivalent axle loads returned as a number.

• Road geometry, pavement loading, sight distance, superelevation, and traffic estimates depend on jurisdictional criteria, design speed, vehicles, grade, friction, climate, drainage, growth, human factors, and survey data. Apply the current road authority standard.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check assumptions against drawings, measurements, current material data, and the applicable design code. Apply required load combinations and safety factors, then obtain qualified review and testing for consequential designs.

• Ampacity Derated

  Adjusted current rating from a base ampacity times a supplied 0–1 derating factor; not a code sizing result.

• Bearing Life L10

  Basic bearing L10 rating life in revolutions: 10⁶(C/P)^p from dynamic load rating, equivalent load and chosen bearing exponent.

• Bolt Shear Capacity

  Nominal single-shear force from bolt shear area times a user-supplied allowable shear stress; not a code-rated connection capacity.