Introduction:
Camber is the slight upward curve given to the road surface in the transverse direction. It is provided to counteract the effect of settlement and to ensure proper drainage of water from the pavement surface. The shape of the camber has a significant impact on the performance and durability of cement concrete pavements.

Straight Line Camber:
The straight line camber is the most suitable shape for cement concrete pavements. This type of camber is a simple upward slope from the center of the road towards the edges. It is also known as a superelevation camber. Here are the reasons why a straight line camber is preferred:

1. Uniform Drainage: A straight line camber ensures uniform drainage of water from the pavement surface. It promotes the flow of water towards the edges of the road, preventing the accumulation of water on the pavement. This helps in maintaining the structural integrity of the pavement and prevents the formation of potholes.

2. Minimal Impact on Ride Quality: A straight line camber provides a smooth transition for vehicles traveling along the road. It minimizes the impact on the ride quality and ensures a comfortable driving experience.

3. Economical: The construction of a straight line camber is relatively simple and cost-effective. It requires less effort and resources compared to other complex camber shapes.

4. Easy Maintenance: Straight line cambers are easy to maintain and repair. Since the shape is simple, any maintenance or repair work can be carried out efficiently without major disruptions to traffic flow.

Other Camber Shapes:
While a straight line camber is the best-suited shape for cement concrete pavements, other camber shapes may be used in certain specific situations:

1. Parabolic: Parabolic camber is commonly used for flexible pavements, such as bituminous roads. It provides a smooth transition for vehicles and helps in reducing the centrifugal forces acting on vehicles during turns.

2. Elliptical: Elliptical camber is used in special cases where specific design requirements or site conditions demand a different shape. It is not commonly used for cement concrete pavements.

3. Combination of Straight and Parabolic: Sometimes, a combination of straight line and parabolic camber may be used to optimize the performance of the pavement. This is done to accommodate different design considerations, such as high-speed roads or steep gradients.

Conclusion:
In conclusion, a straight line camber is the best-suited shape for cement concrete pavements. It ensures uniform drainage, minimal impact on ride quality, and is cost-effective to construct and maintain. While other camber shapes may be used in specific situations, the straight line camber remains the most commonly preferred choice for cement concrete pavements.