Home
Back
Grade Formula:
| From: | To: |
Road grade is the slope or incline of a road surface, expressed as a percentage. It represents the vertical rise per unit of horizontal distance and is crucial for road design, construction, and vehicle performance assessment.
The calculator uses the grade formula:
Where:
Explanation: The formula calculates the ratio of vertical change to horizontal distance, multiplied by 100 to convert to percentage.
Details: Road grade calculation is essential for transportation engineering, construction planning, vehicle safety assessments, and determining appropriate road designs for different terrain conditions.
Tips: Enter rise (vertical distance) and run (horizontal distance) in meters. Both values must be positive numbers greater than zero for accurate calculation.
Q1: What is considered a steep road grade?
A: Grades above 7% are generally considered steep, while grades above 10% are very steep and may require special vehicle considerations.
Q2: How does grade affect vehicle performance?
A: Steeper grades increase fuel consumption, reduce vehicle speed, and require more engine power, especially for heavy vehicles.
Q3: What is the maximum grade for highways?
A: Most highway design standards limit maximum grades to 6-8% depending on terrain and design speed requirements.
Q4: How is grade different from angle?
A: Grade is expressed as percentage while angle is in degrees. A 45° angle equals 100% grade, and 100% grade equals 45°.
Q5: Why measure in meters?
A: Meters are the standard unit in the metric system for road engineering, but the calculation works with any consistent unit of measurement.