What is the summit curve in surveying?

There are two types of the vertical curve, we use in surveying calculation.

1. Valley curve
2. Summit curve

Now, let's see Definition of the curve.

What is the Summit curve? 
The summit curve is one type of the vertical curve. It is provided on the highway or railway when it crossed ridge or valley.

Generally, we determine this curve by parabolic equation.

Summit Curve need to satisfy the basic Condition. The condition is as follow

• There must be constant rate of change of grade.

Parabola fulfill this and so shape of summit curve is mainly parabolic type.

As we see that there is two types of vertical curve, in that the curve that is convexity of upward that is known as the summit curve.

There is some type of this curve that is shown in fig.

Types of summit curve (source:nptel)

For zoom: CLICK on the image

A vertical summit curve is provided when the rising grade join the falling grade.