# What is the Difference between Bridge and Box Culvert?

It may appear that bridge and culvert structures are similar as they both serve the vital need of transportation. However, they are very different in aspects like structural design, construction, components, load-carrying capacity, costs, etc.

Culvert is defined as a tunnel-like structure that facilitates the movement of water from one side to another and supports vehicular, human, and animal loads. On the other side, bridges are linear structures built over large bodies of water or physical obstruction and allow the passage of heavy and speeding vehicles. Bridge structure requires detailed and accurate design in comparison to culvert, and it also needs considerably higher budget, time, and human resources for construction.

Both bridges and culverts follow "American Association of State Highway and Transportation Officials-Load and Resistance Factor Design specifications" (AASHTO LRFD). Still, culverts are not considered bridges because their spans do not exceed 6 m, as per the Federal Highway Administration classifications (FHWA).Â Â

## What is the Difference Between Bridge and Box Culvert?

Table-1 presents the differences between bridge and culvert in terms of definitions, components, design, load-carrying capacity, construction, etc.

Table-1: Difference between Bridge and Culvert Structures

## FAQs

What is a culvert structure?

Culvert is defined as a tunnel-like structure that facilitates the movement of water from one side to another and supports vehicular, human, and animal loads.Â

Is culvert structure considered a bridge?

No, culvert structure is not the same as a bridge because its span does not surpass 6m, per FHWA classifications.

What are the different types of culverts?

1. Pipe culvert (Single or Multiple)
2. Box culvert (Single or Multiple)
3. Arch culvert
4. Bridge culvert

What is the difference between minor and major bridges?

A minor bridge spans about 60 m, whereas a large bridge spans up to 120 m.

What are the components of bridge structure?

1. Abutments
2. Piers
3. Wing walls
4. Beam and girders
5. Bearing
6. Parapet wall and handrail
7. Decks
8. Arch and cables (may not be present in all bridge structures)

What are the components of culvert structure?

1. Single or multiple concrete boxes or pipes
2. Topdeck slab
3. Supporting sides
4. Floors