QN. What are the basic requirements of road alignment? What do you mean by superelevation? How it is different from camber? Write down the significance of the superelevation?
Solution:
Alignment
of the road is defined as the planed centerline of the road where the road will
be constructed.
Requirement
of Road Alignments
- · As
possible as road alignment should be straight
- · Should
be short
- · Should
be economical
- · Road
alignment should balance the cut and fill
- · It
should not passe through the swampy area and populated area
Superelevation:
Superelevation
is the raised portion of the outer edge of the road on the horizontal curve
with respect to inner edge.
e+f= v2/127R
For
Mixed Traffic,
e= V2/225R
Camber
Camber
is the raised portion of the center of road for the drainage purpose
Types
1.
Straight
Camber
2.
Parabolic
camber
3.
Composite
camber
So, Camber
is used for the drainage purpose and superelevation is used to overcome the centrifugal
force on horizontal curve.
Significance
of superelevation
- v It
is provided to overcome the centrifugal force on the horizontal curve of road.
- v Sometimes
it is used as a drainage purpose at horizontal curve.
- v Extra-widening is provided to the curve for
comfort of driver to turn the vehicle.
Finally,
Superelevation and camber are
very important component of the road. So, proper design is required to protect
the road layer and reduce the road accident at horizontal curve of the road.
