Beam leg is the oldest and the simplest kind of bridge. The is additionally known as a girder bridge or stringerbridge.

You are watching: Strengths and weaknesses of a beam bridge

it generally consists of one or much more spans which room supported by one abutment or pier at each end.


In the past, they may have taken the form of a log throughout a stream yet today, they are much more familiar to us as large box steel girder bridges. Miscellaneous kinds of material have the right to be used to build a beam bridge, prefer wooden planks, stone slabs, reinforced concrete, or steel.

Beam Bridge is composed of a strict horizontal structure (a beam) and two supports, one at every end, to remainder it on. These contents directly support the downward weight of the bridge and also any website traffic traveling over it. If two or an ext beams space joined rigidly with each other over supports, the bridge becomes continuous.

A beam bridge needs to be stiff. It demands to resist twisting and bending under load. Normally, the deck that a beam bridge is make of reinforced concrete or metal.

The dimension of the beam, and in details the elevation of the beam, controls the street that the beam have the right to span. Wide flange rolled type beam bridges are generally the many cost-effective type of beam building and construction that is supplied for beam bridges with brief spans.

There are lots of different types of beam bridges. Types of building could include having plenty of beams side by side through a deck across the optimal of them, to the key beam one of two people side sustaining a deck between them. The main beams could be I-beams (also recognized as H-beams), trusses, or crate girders.

Many slam their structure, while others prayer their simplicity and aesthetics. Let’s go v some pros and cons of beam bridges.

Table the Contents

Pros the Beam BridgeCons the Beam bridge

Pros of Beam Bridge

1. An easy Construction

Beam bridges style is thought about to be of the simplest designs of all types of bridges. The simplest form of Beam bridge merely is composed of one an extremely long beam that is supported at either end with a pier. Expanded bridges making use of this style may use multiple piers to assistance the weight of the passenger web traffic that wake up above.

2.Minimal building Cost

Beam bridge is among the most affordable bridge-building options that are easily accessible today. The is a great way to save valuable money ~ above the building of essential infrastructure in addition to design simplicity.

When you require to attach one spot to one more throughout any type of type, this benefit tends to be why it is the very first choice considered by most communities. This bridges can carry out a useful alternate to arch and suspension bridges. A beam bridge is thought about for locations that room cash poor, much more widely provided in urban and also rural areas.

3.Faster building and construction Process

The beam bridge generally doesn’t take much time to build in comparison come other types of bridges. Since most beam bridges today room a mix of steel and also reinforced concrete, a building project does no take lengthy to complete. Yet it additionally depends ~ above the size and also the place of the project. In rural locations where transport of material is the major problem could increase construction time.

4. Advantageous in almost any Location

If you conference a leg while walking along a nature path, there is a better chance of being a beam bridge. Although girlfriend will find that some beam bridges work better than others because of their placement location, this design is beneficial in a selection of situations.

It is the most usual bridge used in highway and railroads. In highways, it can quickly and also effectively administer enough support and also offering room for website traffic to flow beneath in ~ the same time. Native walking trails come interstates, this bridge style is proven to it is in effective.

5. Multiple design Options

Beam bridges covers one an extremely long beam that is sustained at either finish with a pier. Many beam bridges usage a side-by-side beam style that patent a deck to remainder on peak of the supports.

You would have actually the piers, climate the underneath supports, and then the deck. This placement works well with its simplicity to produce a leg that works practically anywhere. Developers can usage H-beams, girders, or trusses to regulate the horizontal stresses the the framework will encounter over time.

Cons of Beam Bridge

1. Limitation the the length of the Bridge

Beam bridges are frequently only supplied for reasonably short distances because, uneven truss bridges, they have actually no built-in supports. Since the supports because that a beam bridge room typically an extremely far apart, it can be daunting for the bridge to preserve its structure integrity over the lengthy haul.

With current technologies, a single span have the right to handle about 100 meter of size for contemporary weight requirements. Anything longer than that will certainly require added spans, which have the right to be attached together as required to kind a much longer bridge.

2.Sagging Issues

Sagging is a common problem with the beam bridge. The bridge’s tons will cause a downward pulling effect. This effect becomes an ext and an ext pronounced as weight is included to the bridge’s load.

Because there is no load transfer developing on the supporting structures of a beam bridge, repetitive heavy weight ~ above a certain location can reason the leg to start to sag. That is why friend will check out some weight boundaries posted on small bridges in landscape communities.

3. Negative Aesthetics

The typical beam leg looks a small like a table. You have actually the deck top top top, the support below, and also piers that occupational to assistance the weight. Through many, they space thought of as the many boring the all bridge designs. Simplicity and also cost-effective construction may be an advantage, but most of the time, that is no aesthetically pleasing. Over there is naught architecturally fascinating about this style since the looks like any other roadway.

4. Gets threaten Over Time

Most beam bridges have actually an mean lifespan that 50 years or less. Beam bridges eventually wear out in time from the wear and tear of sustaining the load from the deck. Even when you usage reinforced concrete and steel for the bridge, a expectancy that receives heavy traffic might have a rated lifespan of simply 25 years. At part point, however, beam bridges will must be replaced.

5. Not constantly Cost-friendly

Beam bridges may be the cheapest design to build from an average standpoint. However, it deserve to be expensive, also for brief spans.

See more: How To Clean Vinyl Pool Liner Stains From A Vinyl Pool Liner

A cheap material for beam bridges is concrete. However, concrete on its own is not solid enough come stand approximately high pressures of tension (pulling). Concrete requirements to it is in reinforced through expensive stole mesh that increases the expense of construction.