Types of Roads - Design & Functional Classification of Roads

Road classification system groups roads into a limited number of clearly defined road types:

Purpose of Road Classification

A road network is composed of various types of roads, each of which performs a particular service in facilitating vehicular travel between points of trip origin and destination, and in providing access to property. Road classification is the orderly grouping of roads into systems according to the type and degree of service they provide to the public.

Also See: Typical Road Structure

Factors Affecting Classification of Roads

Many different classification systems have been introduced and used for particular purpose. The basis for some of these classifications is:

1. Legal control
2. Surface type
3. Function
4. Geometric elements
5. Location
6. Traffic volume

Seldom do these classification system differentiate between different types of roads on basis of service which is is essential for road designer.

Classification of Roads on the Basis of Design

This system separates roads:

• On the basis of differences in traffic service and land services.
• On the basis of geometric design features.

The eight primary divisions in this system are:

1. Rural and urban:

It refers to predominant characteristic of the adjacent land use and not only to jurisdictions boundaries or features of typical cross-section.

2. Geometric design:

For geometric design purposes it is essential to divide each of these divisions. For a given road geometric design elements are affected by traffic volume. However it is significant for classification only in determining the number of lanes and whether road should be divided or undivided.

3. Other variables

Affecting geometric design are:

Development characteristics of the land surrounding, the road and the travel habits of the local population.

1. The type of terrain road passes through
2. Financial resources available
3. Population density
4. Design speed is the measure of quality and is therefore the final sub division.

Types of Roads on the basis of Function

* UAD100:- Urban, Arterial, Divided, 100km/h (design speed)

Freeway is preferred because it is more descriptive of the type of the traffic movement.

Classification of Roads Video