Variables
Description
What is this formula?
Haul Road Grade Resistance estimates the additional resistance experienced by a haul truck when traveling on an inclined road.
In mining haulage engineering, grade resistance is commonly expressed in kilograms of resistance per tonne of vehicle weight. A widely used approximation states that each 1% of road gradient produces approximately 10 kg/t of additional resistance.
This parameter is fundamental for estimating truck performance, speed, fuel consumption, and required engine power.
When to use it
Use this formula when:
- Designing haul roads.
- Evaluating truck performance.
- Estimating total haulage resistance.
- Calculating fuel consumption.
- Planning mine transportation systems.
Example
A haul road has a gradient of 8%.
Data:
G = 8%
Formula:
GR = 10 × G
Substitution:
GR = 10 × 8
Result:
GR = 80 kg/t
The road generates an additional grade resistance of 80 kg/t.
Applications
- Open-pit mining
- Haul road design
- Truck performance analysis
- Fleet planning
- Fuel consumption studies
- Mine transportation engineering
Note
This formula is an engineering approximation widely used in mining and earthmoving operations. It assumes moderate road grades and is intended for vehicle performance calculations. More detailed analyses may consider rolling resistance, vehicle dynamics, tire characteristics, acceleration, and road surface conditions. The coefficient of 10 kg/t per 1% grade is a commonly accepted industry approximation.