If the width of carriage way is 12.5 metres outer edge 50 cm higher than the inner edge, the required super elevation is:

Concept:

Super Elevation:

• To counteract the effect of centrifugal force and to reduce the tendency of the vehicle to overturn or skid, the outer edge of the pavement is raised with respect to the inner edge, thus providing a transverse slope throughout the length of the horizontal curve. This transverse inclination to the pavement surface is known as superelevation or cant.

If the pavement is rotated about the inner side,

Then the rise of the outer edge = e × W.

If the pavement is the rotated about center line,

Then rise of the outer edge = \(\frac{e × W}{2}\)

Where,

e = Superelevation

W = Width of Pavement

Calculation:

Given,

 Rise of outer edge with respect to inner = 40 cm, W = 10 m = 1000 cm

It is given outer edge is 40 cm higher with respect to the inner edge

∴ 40 = e × 1000

e = \(\frac{40}{1000} = \frac{1}{25}\)

The required elevation is 1 in 25.