TUTORIALS

How to Calculate Superelevation of Road Highways

Super elevation is provided on curves on road. When curve comes and when car turns and at the time of turn, centrifugal force acts on car, increasing the chances of slipping.

In order to resist centrifugal force, super elevation force is created by drawing super elevation.

Road has two edges. One is inner edge and the other is outer edge. Height of outer edge is increased, forming a shape of triangle.

Inner edge is at lower level. Super elevation force resist centrifugal force, hence the slipping chances of car turn out to be nullified/ineffective/null and void. Super elevation depends on height.

Some Super elevation components:

• Begin tangent run out [Super elevation starts, height starts increasing in points] L/3
• Begin runoff
• End runoff [Super elevation maximum]
• Full super elevation [Height maximum]
• When curve starts, full super elevation portion starts

In normal crown, normal slopes are there. When curve portion comes, slope becomes different for the reason that outer edge has to be provided super elevation. At reverse crown, elevation is above zero.

At level crown, slope is zero. Full super elevation is at curve centre portion.

For additional info view the video:

Lecturer: Civil Engineering - Shylus Updates