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What is Camber in Road - Types of Camber and Advantage of camber & Method of providing

Today discuss about camber in Road , the convexity Or slope provide to the cross section of the surface of carriage way to quickly drain off water. It's called as camber. The slope of the line joining the crown and the edge of the highway surface.

camber in road

A steep camber is preferred in areas of heavy rainfall and a flat camber in regions of low rainfall. Generally in heavy rainfall prprovideing 1in 50 and 1in 25.
The design values of cambers are primarily based on the type of pavement of r0ad and also on the average amount of rainfall in the particular area. Steep cambers are useful for eliminating surface water.

 But they are not recommended since they will wear down the road surface. Generally, cambers of slope 2 to 3% are arranged.

On straight sections of roads, they are shoulders with higher cross fall relating to that of the carriageway by 0.5 percantage.

 Types of camber-:
There are normally three types of cambers provided along the road surface, namely straight line or sloped camber, parabolic camber and composite camber.

  • Straight line or sloped camber
  • Parabolic camber
  • Composite camber


1) Straight line or sloped camber:-

These are provided with two equal uniform straight line slopes at two sides of the crown and are also known as the Plane cross slopes. They are normally adopted for very flat slopes such as RCC or PCC Pavement.

2) Parabolic Camber:-

In parabolic camber, the cross slope  in the shape of simple quadratic parabola. In this case, the ordinate Y varies as the square of abscissa X (simple parabola equation).
Parabolic cambers are designed for fast moving highways. A favourable condition for  the overtaking operation is provided due to the  cross sloped curve. As the slope decreases inward to the road edge, the flow of surface water away from the pavement is enhanced. One disadvantage of parabolic cambers is that they are very difficult to construct.

3) Composite camber:-

Composite camber may be composed of partly straight and partly parabolic line or two straight lines having different slopes. Normally central part of the road is made parabolic and provided with straight slopes near edges. This helps to decrease the intensity of pressure by increasing the contact area of the wheel .

Advantage of camber:-

This prevents rain water to accumulate at local  depressions or shrinkages and forming water pools around the road surface that are disagreeable to the public as well as to the road structure. Camber provides quick drainage of rain water and also saves the foundation course of this road structure from weakening from the percolation of rain water to it through the road surface.

Method of Providing Camber in Road:-

Normally, the camber is provided on the straight roads by raising the center of the carriageway with respect to these edges, forming a crown or highest point on the center-line.  At horizontal curves with superelevation, the surface drainage is effected by raising the outer edge of the pavement with respect to the inner edge while providing this desired superelevation.The rate of camber or cross slope is generally designed by 1 in n, which means the transverse slope is at ratio 1 vertical to”n” horizontal. Camber can be expressed in percentage. If the camber is n%, the cross slope is n in 100.

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