Cross-Section of a Road – Geometric Design of Highways

Cross-section of a road gives some of the important design elements and features that is observed in a highway. A general cross-section of a highway in a cutting as well as on an embankment is shown in Figure 1 below. 

Fig.1:  Cross-Section of a Road – Geometric Design of Highways 

These features in the cross-section of the highways vary depending on the type of pavement. The pavement can be flexible or rigid pavement. 

Also Read: What is Geometric Design of Highways? Objectives and Design Elements

Cross-Section of a Flexible Pavement 

Consider a flexible pavement as shown in the figure-2 below. The cross-sectional elements of flexible pavement in the order of their construction are: 

Fig.2. Cross-Section of a Flexible Pavement

1. Embankment 
2. Subgrade 
3. Subbase 
4. Base 
5. Wearing Course or Surfacing 
6. Carriage Way 
7. Treated Shoulder 
8. Earthen Shoulder 

Read More: Difference between Subbase and Subgrade

Cross-Section of Rigid Pavement 

The cross-section of a rigid pavement involves (Figure 3) 

Fig.3. Cross-Section of Rigid Pavement

1. Embankment 
2. Subgrade 
3. Sub-base 
4. Concrete Pavement 
5. Carriage Way 
6. Treated Shoulder 
7. Earthen Shoulder 

Also Read: What is Camber in Road Construction?