What is the main purpose of applying grade compensation on a horizontal curve?

Explanation:

Grade Compensation:

1. The main purpose of applying grade compensation on a horizontal curve is to counteract the effects of both the curve and the gradient.
2. This is done by adjusting the cross-slope (cant) of the road, ensuring that vehicles experience less resistance due to friction, especially when navigating through curves on sloped surfaces.
3. Grade compensation helps in maintaining better vehicle control and reducing the likelihood of skidding or slipping.

 Additional Information

Grade compensation is a critical design feature in road engineering, particularly when horizontal curves are combined with inclines (or gradients). Here's a more detailed explanation:

1. Purpose: When vehicles travel on a curve, they experience a centrifugal force that pushes them outward, away from the center of the curve. On sloped roads (gradients), this force is further complicated by gravity, which can either aid or hinder the vehicle's motion depending on whether the slope is ascending or descending. Grade compensation addresses these issues by modifying the cross-slope of the road to balance the forces at play, ensuring the vehicle remains stable while navigating the curve.

2. How It Works: In a typical curve, the outer edge of the road surface is raised to counteract the centrifugal force. This is known as the cant or superelevation. On a curve with a gradient, this cant may need to be adjusted to account for the additional gravitational pull, which would otherwise increase friction between the tires and the road surface, making the turn more difficult and less safe.