23 Different Types Of Bridges

A bridge is a structure built over obstacles such as rivers and valleys. It plays an important role in the rise of transportation, local and worldwide trade, as well as the spreading of knowledge.

One of the earliest and simplest types of bridges is stepping stones. The first human-made bridges with substantial span were intentionally felled trees. There were several innovations in bridge designs during the 18th century. The first book on building bridges was written by French engineer Hubert Gautier in 1716.

In the late 1770s, humans achieved a milestone in bridge technology with the development of the Iron Bridge in Shropshire, England. Between the 18th and 19th centuries, thousands of bridges were built in the United States and Canada, reminiscent of earlier designs in Switzerland and Germany.

Today’s bridges strongly vary in terms of their appearance, construction materials, carrying capacity, and movable sections. They all can be categorized in several ways. Below we have listed the most popular types of bridges in the world that serve various purposes.

23. Clapper Bridge

Postbridge dating from the 13th century

Span range: Short

The clapper bridge is an ancient form of bridge in which large flat stone slabs (often schist or granite) rest on piles of stones. Most of them were built in medieval times to carry a trackway across a river.

Postbridge is a perfect example situated next to the East Dart river in the English country of Devon. Its slabs are more than 6 feet (2 m) and over 13 feet (4 m) long. Each slab weighs more than 8 tons. It was built in the 13th century to allow packhorses to cross the river, carrying tin to the stannary town of Tavistock.

22. Natural Bridge

A 92-foot tall natural arch, Azure Window

Span range: Short

Many naturally created arch formations resemble a bridge. Those bridges could be have been formed from river flow, wind erosion, or collapse of lava tubes.

Azure Window, for example, on the island of Gozo, was created by the collapse of a sea case, probably during the 19 century. Another famous example is Natural Bridge in Virginia. It’s a geological formation comprising a 215-foot tall natural arch with a span of 90 feet.

21. Beam Bridge

A footbridge using beams over a stream

Span range: Short

A Beam (or stringer) bridge is the simplest structural form for bridge spans supported by a pier at each end. In order to construct such a bridge, all you need is a beam (a rigid horizontal structure) and two supports on each end to rest it on. These parts directly support the downward weight of the structure and traffic traveling over it.

Unlike suspension and truss bridges, they are used for relatively short distances. Since the support is provided by piers only, the farther apart the piers get, the weaker the structure gets. Thus, such bridges rarely span more than 250 feet.

20. Truss Bridge

Through truss General Hertzog Bridge | Wikimedia

Span range: Short to medium

Instead of a single beam having to withstand all of the forces, a series of beams and trusses are used. A truss is a triangular frame that spreads the tension and compression forces along the bridge.

There are numerous ways to build a truss bridge, but they all share the same goal: distribute the tension and compression forces so that the bridge doesn’t collapse. Since strong beams arranged in a triangle cannot be distorted by stress, a truss gives a stable form capable of supporting heavy external loads over a significant span.

Unlike other designs, a truss bridge can carry its roadway on its structure. The load can be carried on the bottom (below the major truss structure), along the middle (through truss), and above truss (deck truss). This makes the bridge versatile as well as economical to construct.

19. Covered bridge

The longest covered bridge is 1,282-feet long | Hartland Bridge in New Brunswick 

Span range: Short

The term ‘covered bridge’ refers to a specific kind of structure, not just any bridge with a roof. It is a timber-truss bridge that distributes the weight of the load-bearing deck.

They are covered to protect the wood materials from the weather. Uncovered wooden bridges usually last only 20 years due to the effects of rain and sunlight. When they are externally covered, their lifespan increases up to 100 years.

At present, there are nearly 1,600 covered bridges in the world (that are still in use). Most of them are built to cross streams and have a short span.

18. Arch Bridge

A double stone arch bridge (named Meganebashi) in Japan | Wikipedia

Span range: Short

They came into use over 30 centuries ago and remained popular until the industrial revolution and material sciences enabled architects to build more advanced and efficient bridge designs.

The underside of an arch bridge looks very different than other types of bridges. All bridges have a curved underside, which looks like someone has cut a semicircle out of the bridge’s bottom.

Actually, the curve design allows the load to spread out instead of pushing it in the vertically downward direction. The load spreads out to the supports at each end (known as abutments). The arch and abutments make the bridge strong enough to carry heavy loads.

17. Through Arch Bridge

World’s 5th longest steel arch bridge | Bayonne Bridge | Wikimedia 

Span range: Long

It is the most common form of arch bridge, whose top rises above the deck and base remains below or at the deck. The middle segment of the deck is supported by the arch via tie bars or suspension cables. The ends of the bridge are usually supported from below.

Sydney Harbour Bridge (in Australia), Tyne Bridge (in North East England), Bayonne Bridge (in New York) are some well-known examples of through arch bridge.

16. Moon Bridge

Jade Belt Bridge in Beijing, China 

Span range: Short

It’s a pedestrian bridge, of which the semicircular arch completes a 360-degree circle through its reflection in the water, and reminds of the full moon. These structures were originated in Asian culture. Initially, they were constructed in China and later introduced to Japan.

Moon bridges are mostly made of stone, wood, and metal. Since they are steep, they have the advantage of not using space from the adjoining fields. It is the perfect way to allow foot traffic above the structure and boat traffic beneath, without requiring a gradual approach for the bridge.

15. Movable Bridge

Tower Bridge in London

Span range: Short movable portion

As the name suggests, these bridges move to allow passage for boats and barges. It can be either a vertical-lift bridge, a drawbridge, a swing (pivot bridge), or a transporter bridge.

They are powered by electric motors, whether hydraulic pistons, operating winches, or gearing. Moveable bridges in their entirety can be quite long, but the length of the moveable part is generally restricted to a few hundred feet due to engineering and cost considerations.

The major drawback is that the road traffic must be halted when the bridge is opened for the passage of waterway traffic. It also requires considerable maintenance because of heavy machinery and moving elements.

14. Stressed Ribbon Bridge

Leonel Viera Bridge | The first stressed-ribbon bridge constructed in Uruguay in 1965

Span range: Medium

A stressed ribbon bridge (also called a catenary bridge) is a tension structure. It has two or more suspension cables embedded in the deck. These cables follow a catenary arc (a curved formed by a freely-hanging wire) between supports and provide stiffness to the bridge.

The structure is usually made of concrete reinforced by steel tensioning cables. These bridges are very aesthetic, economical, almost maintenance-free structures.

13. Spiral Bridge

Spiral ramp to Nanpu Bridge in Shanghai, China | Image credit: Jakob Montrasio/Flickr 

Span range: Medium to long

A spiral bridge loops over its own road and is useful in steep terrain. The structure rises on a steady curve until it has completed a loop, passing over itself as it gains elevation, allowing the vehicles to gain heights in a relatively short horizontal distance.

It’s a better alternative to zig-zag roads and avoids the need for vehicles to stop and reverse direction while ascending/descending. The shape of the structure doesn’t form a spiral but a helix. Many multi-story car parking buildings feature such a design.

12. Box Girder Bridge

Open trapezoidal composite box girder during the construction

Span range: Medium to long

In these bridges, the main beams consist of hollow-box-shaped girders. The box girder is made of structural steel, prestressed concrete, or a composite of reinforced concrete and steel.

The box is usually trapezoidal or rectangular in cross-section. It reduces the slab thickness, weight of the bridge, as well as construction costs, while providing higher strength per unit area of concrete. Such bridges are mostly used for highway flyovers and modern elevated structures of light rail transport.

11. Segmental Bridge

Construction of a segmental bridge on the ‘Dallas High Five Interchange’

Span range: Long (over 100 meters)

Unlike conventional construction techniques that build structures in large sections, segmental bridges are constructed in small parts called segments (one piece is installed at a time).

They are made of concrete parts that are either built at another location and transported to the construction site or built fully at the final location. Although this type of design is very economical for long spans, it requires high-tech machines and a lot of safety precautions during construction.

10. Viaduct

Glenfinnan Viaduct in the UK

Span range: Long

A Viaduct is made of a series of small spans between tall towers. Its purpose is to carry a road or railway over a valley or wetland. Although they are much more cost-efficient than bridges or tunnels with larger spans, they generally lack vertical and horizontal clearance for large ships.

The ones that are constructed over water make use of successive arches or islands. They are usually merged with tunnels or other types of bridges to cross navigable waters as viaduct sections.

9. Cantilever Bridge

Forth Bridge in the east of Scotland 

Span range: Medium

These bridges are build using cantilevers, structural elements that extend horizontally and are supported at only one end. For small footbridges, cantilevers could be simple beams. However, for long cantilever bridges, box girders (built from prestressed concrete) or trusses (built from prestressed concrete) are used.

Cantilevers are useful for spaning a waterway without dividing it with river piers. They are mostly used for pedestrians, motor vehicles, and trains.

The world’s longest cantilever bridge is Pont de Québec. It was built in Lévis and Quebec, Canada, in 1917. The project failed twice and took more than three decades to complete.

8. Suspension Bridge

Akashi Kaikyō Bridge in Japan 

Span range: Medium to long

In suspension bridges, the cables supporting the deck are suspended vertically (called hangers) from the main cable. This main cable is anchored at both ends of the bridge since any load applied to the structure is transformed into a tension force.

Constructing a suspension bridge requires less material, and longer spans can be achieved compared to other bridge types. It can also better withstand earthquakes than heavier and more rigid bridges.

7. Cable-Stayed Bridge

Design of suspension (top) and cable-stayed (bottom) bridge

Span range: Medium

Cable-stayed bridges have been widely used since the 19th century. They consist of one or more columns (or towers) with cables directly supporting the bridge deck. The columns absorb and deal with compressional forces.

Unlike suspension bridges, these bridges have cables that run directly from the tower to the deck, forming a series of parallel lines or a fan-like pattern. They are optimal for spans shorter than suspension bridges and longer than cantilever bridges. In this range, the cable-stayed bridge remains economical and appears elegant due to the relatively small girder depth.

6. Transporter Bridge

Middlesbrough Transporter Bridge built in 1911 

Span range: Short

Transporter bridges carry a segment of roadway across a river. They have been used to cross navigable rivers or other water bodies, where there is a need for ship traffic to be able to pass.

It’s a rare type of bridge: fewer than 30 structures have been built so far. Of those, only twelve bridges are being used today. Middlesbrough Transporter Bridge, for example, is a 2,600-ton steel structure built across the River Tees, England. It provides a span of 570 feet to accommodate sailing ships.

5. Girder Bridge

Multispan plate girder bridge deck on concrete piers 

Span range: Short to medium

As the name suggests, these bridges use girders made of either steel or concrete. Girder is the main horizontal support of the bridge that supports smaller beams on the deck. Most girders have an I-beam cross-section containing two load-bearing flanges separated by a stabilizing web.

Girder bridges have come a long way from their limited short-span applications to cost-effective functional form, becoming one of the most widely used bridge types of this era. Advances in material sciences and construction techniques continue to promote more widespread uses of such bridges in applications that were unheard of several decades ago.

4. Extradosed bridge

Ganter Bridge in Switzerland

Span range: Medium

The extradosed bridge combines the main elements of a cable-stayed bridge and prestressed box girder bridge. It uses smaller pylons than the cable-stayed bridge, and a significantly thinner girder/deck structure than used on the girder bridge.

They are relatively expensive and material inefficient. Almost any span that could be built by an extradosed bridge could be spanned more efficiently (with less material) with a cable-stayed bridge, or more inexpensively with a continuous girder bridge. However, they are used when overall navigation clearance, height, or aesthetic requirements make girder or cable-stayed alternatives less feasible.

3. Trestle Bridge

Montana trestle bridge | Image credit: Wikimedia

Span range: Short

A trestle bridge contains several short spans supported by closely-spaced frames. The trestle, which is used as bridge support, is a rigid frame made of either wood or iron.

Iron and timber trestles were widely used across the world in the 19th century. In fact, timber bridges once accounted for up to 3% of the total length of the average railroad. Although these bridges are largely outdated, they are still invaluable to infrastructure systems. For example, steel or timber trestles are often built in areas where a filled-in bridge could block potential floodwaters.

Read: 15 Tallest Buildings In The World

2. Cantilever Spar Cable-Stayed Bridge

Assut de l’Or Bridge in Spain

Span range: Short to medium

It’s a modern variation of the cable-stayed bridge. In such bridges, the distribution of forces doesn’t depend entirely on the cantilever action of the spar (supporting tower). The weight distribution in the spar and the angle of the spar away from the bridge play a significant role in reducing the overturning forces applied to the spar foundation.

In some bridges, the spar is titled up to an angle where it is counterbalanced by a structural tail. Many designs feature a curved backward spar to support the weight of the deck.

1. Side-Spar Cable-Stayed Bridge

Esplanade Riel in Manitoba

Span range: Medium

It is quite an uncommon bridge in which cable support doesn’t span the roadway; instead, it is cantilevered from one side. The cable paths are usually aligned with the centerline of the bridge. Forces are transmitted through the cable stays (tension forces), then into the tower (compression forces), and then into the foundation.

Read: 12 Longest Bridges In The World

Such bridges would be suitable for regions where the road goes in the upstream direction, crosses a stream, and turns back on the other side in the downward direction. By building a portion of the turn on the structure, the turn can be made more gentle, allowing traffic to move faster.

Frequently Asked Questions

What is the most efficient and strongest type of bridge?

The top priority of any bridge construction project is to make the structure safest and cost-efficient. Truss bridges are the strongest and extremely cost-effective of all bridge designs because they have a high strength-to-weight ratio.

The model experiments show that the Howe truss bridge can support the maximum load. It contains chords, verticals, and diagonals: the vertical members are in tension while diagonal members are in compression. 

What is the weakest type of bridge?

The strength of a bridge depends on many factors such as materials used in the structure and construction speed, but as far as design is concerned, beam bridges have more uneven weight distribution as compared to other types of bridges. The weight is pressed directly downward, toward any underneath support, which makes the central part of the bridge the weakest.

Which is the most expensive bridge ever built?

The eastern part of the iconic San Francisco–Oakland Bay Bridge had deteriorated to such an extent that it to be completely replaced. The replacement project cost over $6.5 billion (260 times more than the original estimate of $250 million), making it the most expensive bridge in the world.

This self-anchored suspension bridge crosses the San Francisco Bay between Yerba Buena Island and Oakland. The replacement span, completed in 2013, is 2.2 miles long and expected to last at least 15 decades with proper maintenance.

Read: Manhattan Bridge: Facts | Design | History

Which city has the most bridges in the world?

Hamburg, the second-largest city in Germany, has the highest number of bridges in the world. Its river and canals are crossed by nearly 2,500 bridges, more than Venice, London, and Amsterdam combined.

How many bridges does the USA have?

There are over 600,000 bridges in the US. About 45% of these are under the financial jurisdiction of state governments and 38% are managed by county authorities.

According to the Statista report, there are nearly 54,600 road bridges in Texas, 27,000 in Ohio, 26,800 in Illinois, and 25,800 in California.