Related Resources: calculators

Vehicle Hill Climbing Gradability Adhesion Equation and Calculator

Power Transmission Design and Engineering
Engineering and Design Applications

Vehicle Hill Climbing Gradability taking into Account Road Tire Adhesion Equation and Calculator

 

 

Where:

p_R = Hill-climbing performance taking friction into account, in %
µ = Tire to road surface coefficient of friction, on wet asphalt surface ≈ 0.5
f_R = Coefficient of rolling resistance, on wet asphalt road surface ≈ 0.015
G_an = Sum of the axle loads of the driven axles as mass, in kg
G_Z = Overall combined mass, in kg

Coefficients of Rolling Resistance

Table 1: Coefficients of Rolling Resistance

Road surface	Coefficient fR
Good asphalt road	0.007
Wet asphalt road	0.015
Good concrete road	0.008
Rough concrete road	0.011
Block paving	0.017
Poor road	0.032
Dirt track	0.15...0.94
Loose sand	0.15...0.30