Reverse Curve Definition
A reverse curve, also known as a C-curve or a vertical reverse curve, is a compound curve formed by two circular arcs. These arcs connect points or segments that curve in opposite directions.
Key Characteristics of a Reverse Curve
Understanding the components of a reverse curve is crucial:
- Two Circular Arcs: It fundamentally consists of two distinct circular arcs joined together.
- Radii Options: These arcs can either have the same radius or different radii. This flexibility allows for adaptation to various site conditions.
- Center of Curvature Position: The defining feature is that the centers of curvature for these two arcs lie on opposite sides of the common tangent. The common tangent is the line that is tangent to both arcs at their point of connection (the Point of Reverse Curve or PRC).
Why Option 4 is Correct
Option 4 accurately describes a reverse curve:
- It correctly states the curve involves two circular arcs.
- It includes the possibility of both same or different radii for these arcs.
- Crucially, it specifies that the centers of curvature are on the opposite side of the common tangent, which distinguishes it from other types of curves and incorrect definitions.
Other options are incorrect because they either restrict the radii unnecessarily (options 2 and 3) or incorrectly place the centers of curvature on the same side of the tangent (options 1 and 2).
Important Questions from Curves
The difference in length between the arc and the subtended chord on the earth's surface is taken as 500mm in:
The length of a simple circular curve of radius R meters and deflection angle D degrees will be
The angle of intersection of a curve is the angle between the
The shift of a circular curve is given by __________
Where,
L = Length of transition curve and R = Radius of the circular curve
The point where the alignment changes from a straight line or tangent to a circular curve is called as-
