In this article, we will learn about the summit curve.
Normally there are two types of vertical curves that are used in surveying.
- Summit curve
- Valley curve
Definition of Summit Curve
A summit curve is a type of vertical curve. It is given as a road or railroad when crossing a ridge or valley.
Usually, this curve is defined by the parabolic equation. There are basic conditions that the summit curve must meet.
- There must be a constant rate of change in grade.
Parabola fulfills this condition hence the summit curve is mainly a parabolic type.
Some important types of the summit curve are shown in the below figure.
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- Summit curves are vertical curves with convexity upward & concavity downward.
- It can be formed by two gradients when the rising grade joins the falling grade.