The classification of roads based on the construction material is essential for understanding the design, durability, and maintenance requirements of different types of roadways. Here, we explore the main types of roads classified according to the materials used in their construction.

1. Bituminous Roads (Flexible Roads)

Bituminous roads, also known as asphalt roads, are constructed using bituminous materials. These roads have a layered structure where the top layers are flexible and can distribute the load over a wider area.

What are the Key Features:

• Flexibility: The bituminous surface can flex under traffic loads without cracking.
• Smooth Surface: Provides a smooth driving surface that reduces vehicle wear and tear.
• Easy Repairs: Damages such as potholes can be quickly and easily repaired.

Here are some Common Uses:

1. Urban and rural roads
2. Highways and expressways
3. Airport runways

Here are some Examples:

• Most city streets
• National and State Highways

2. Cement Concrete Roads (Rigid Roads)

Cement concrete roads, also known as rigid roads, are constructed using cement concrete, which provides a rigid and strong surface. These roads are designed to bear heavy loads without significant deformation.

What are the Key Features:

• Durability: Highly durable with a long lifespan, requiring less frequent maintenance.
• High Strength: Can support heavy traffic loads.
• Low Maintenance: Less prone to weather-related damage compared to bituminous roads.

Here are some Common Uses:

• Urban roads with heavy traffic
• Industrial areas
• Major highways

Here are some Examples:

• Urban arterial roads
• Certain segments of National Highways

3. Water Bound Macadam (WBM) Roads

WBM roads are constructed using crushed stone aggregates bound together with water. This type of construction creates a stable and relatively inexpensive road surface.

What are the Key Features:

Cost-Effective: Low initial construction cost.

Ease of Construction: Simple construction techniques using locally available materials.

Moderate Durability: Suitable for low to moderate traffic volumes.

Here are some Common Uses:

• Rural roads
• Secondary and feeder roads

Here are some Examples:

• Village roads
• Access roads in less trafficked areas

4. Gravel Roads

Gravel roads are unpaved roads with a surface made from compacted gravel. These roads are often found in rural areas where traffic volumes are low.

What are the Key Features:

• Low Cost: Cheaper to build compared to paved roads.
• Quick Construction: Can be constructed quickly with minimal resources.
• Basic Surface: Provides a basic driving surface, which can become rough and dusty.

Here are some Common Uses:

• Rural and agricultural access roads
• Temporary roads at construction sites

Here are some Examples:

• Farm roads
• Remote area access roads

5. Murrum Roads

Murrum roads are constructed using murrum, a type of laterite soil. This material is often used in rural areas where murrum is readily available.

What are the Key Features:

• Cost-Effective: Utilizes locally sourced materials, reducing transportation costs.
• Suitable for Rural Areas: Adequate for areas with low traffic volumes.
• Natural Appearance: Blends with the rural landscape.

Here are some Common Uses:

• Rural village roads
• Pathways in agricultural areas

Here are some Examples:

• Rural roads in regions with laterite soil

6. Earthen Roads

Earthen roads are the most basic type of roads, constructed using natural soil. These roads are often found in very rural or undeveloped areas.

What are the Key Features:

• Very Low Cost: The cheapest type of road to construct.
• Simple Construction: Requires minimal equipment and materials.
• High Maintenance: Prone to erosion and damage, especially during rainy seasons.

Here are some Common Uses:

• Temporary roads
• Low-traffic rural areas

Here are some Examples:

• Village paths/roads
• Temporary access roads in undeveloped regions