Road Patterns Meaning:
When the road is constructed in different shapes for proper management of traffic like rectangular, radial, hexagonal, etc, and also for connecting branch roads with main roads it is called road pattern.
The main principle of road patterns is to reduce the time and distance taken by the vehicle to reach the destination. It also focuses on the interconnection of branch roads.
It enhances the response time for normal vehicles as well as emergency vehicles like ambulances, fire brigades, etc. to reach the destination.
Road pattern also plays an important role in the management of traffic but it is neglected by most the countries.
Different Types of Road Patterns:
1. Rectangular or Block Pattern Road:
In this pattern, the whole area is divided into rectangular blocks. Streets roads intersect with each other at the right angle and the main roads always pass through the center and it should be wide enough. Branch roads may be narrow as compared to main roads.
this pattern is adopted in Chandigarh where the connection between the roads is continuous and the traffic jam condition does not exist.
Advantages of Rectangular or Block Pattern Road:
- Rectangular blocks can be further subdivided into smaller rectangles that can be used to construct back-to-back buildings that have roads in front.
- It is widely adopted on city streets.
- Construction and maintenance are quite easy.
Disadvantages of Rectangular or Block Pattern Road:
- This is not convenient as the roads are perpendicular to each other. This increases the rate of accidents due to poor visibility at the vertical junction.
2. Star and Block Pattern of Road:
The entire area is divided into a radial network of roads leading out from the centre, with a block pattern network of roads between the radial main roads. It is a combination of star and block patterns.
Advantages of Star and Block Pattern of Road:
- It reduces the level of congestion at the primary bottleneck location.
- If one radial road is blocked then another can be used as an alternative.
- Less risky as compared to the rectangular pattern.
Disadvantages of Star and Block Pattern of Road:
- This is effective only if the two-lane ramp traffic does not have to merge at the downstream end of the ramp.
- Lack of safety equipment like rail transition, crash attenuators, and post support base.
3. Star and Grid Pattern of Road:
star and grid pattern is adopted in India. this pattern is formed by the combination of Star and Grid Pattern.
Like the others, a radial network of roads runs out from the center. Then, the main radial roads are interconnected providing a grid pattern.
this pattern was an eye doctor in Nagpur road plan their road are interconnected such that a star shape grid
Advantages of Star and Grid Pattern of Road:
- It improves the traffic flow in both directions utilizing Savannah’s cellular structure.
- It reduces the cut-through traffic.
- It provides high safety to vehicular traffic with a high proportion of 3-way intersections.
- It increases the efficiency of land usage and unit density.
disadvantages of Star and Grid Pattern of Road:
- Higher construction costs due to the need for additional traffic signals, road markings, and lighting.
- Splitter islands should be extended far enough.
4. Star and Circular Pattern of Road:
This is the pattern in which the main roads (radial roads) originate from the central point and are connected by concentric roads (ring roads) which also radiate outward.
Advantages of Star and Circular Pattern of Road:
- The roundabouts present in this pattern improve the efficiency of the traffic flow. It also reduces fuel consumption and vehicle emissions.
- Using a circular pattern in place of traffic signals reduces the possibility of rear-end crashes.
- It is safe as compared to the above patterns because vehicles travel in the same direction.
Disadvantages of Star and Circular Pattern of Road:
- There is necessary proper provision of the traffic signal, road markings and lighting to alert the drivers that they are approaching a roundabout.
- Splitter Islands should be extended far enough to provide pedestrian refuge (crosswalk) and to delineate(describe ) the roundabout.
5. Hexagonal Pattern of Road:
In this pattern entire area is divided into hexagonal patterns. The three roads meet at each corner of the hexagon along the boundary of the area formed by the sides of the hexagon which can be further subdivided into suitable sizes.