Question

Draw a typical cross section for a two-lane highway and explain the principal components.

Answer 1

Typical cross section for a two-lane highway.

Principal components are:

Right of way: right of way or land with is the width of land acquired for the road along its alignment.

It should be adequate to accommodate all the cross-sectional elements of highway and may reasonably provide for further development.

Width of formation: It depends on the category of the highway and the roadway width and roadway margins and for two Lane roads it is 7 metre and after accounting for kerb it is 7.5 metre.

Camber: Ca​​mber or cant the cross slope provided to raise middle of the road in the transverse direction to drain of water from the road surface. The objective of providing camber area are:

-surface protection especially for gravel and bituminous road.

- subgrade protection by proper drainage

-quick drying of payment which in turn increases safety.

Shoulder: shoulders are provided along the road is and is intended for accommodation of stopped vehicles ,serve as an emergency land for vehicles and provides lateral support for base and surface courses

the crossfall for each shoulder should be at least 0.5% steeper than the slope of the pavement subject to a minimum of 3%.

Catch basin: It's purpose is to drain rain water from the highway into the sewerage system. A highway drain is the pipe connecting the highway gully to the surface water sewer.