A truss bridge is a variation of a beam bridge design that includes multiple vertical, horizontal, and diagonal members that reinforce the bridge. The bridge member’s designs are triangular-shaped, which helps to strengthen the bridge. The triangular shapes, when put together, are called a “truss” and will usually span over an extended length .
To better understand what a truss bridge looks like, it’s important to know its purpose, what you would use one for, and the benefits it provides.
What’s the Purpose of a Truss Bridge?
A pedestrian truss bridge accommodates the following loads on the structure:
- Live loads include:
- Expected foot traffic
- Expected bike, equestrian, or lightweight vehicle traffic
- Dead loads include:
- Weight of the structure itself
- Decking (wood, FRP, etc.)
- Snow and wind loads (can vary greatly depending on location)
Trusses handle the forces using the members arranged in triangular shapes to transfer forces efficiently through a structure to maximize the strength of the structure using minimal materials. The truss bridge design is popular because it can support a large amount of weight without requiring a lot of material, making it a cost-effective bridge option.
Truss bridge designs can use various materials to fit your needs.
- Fiber reinforced polymer (FRP)
What Does a Truss Bridge Look Like?
There are many different types of bridges used for highways, walkways, train trestles, and others. Each of those bridges will transmit horizontal and vertical forces differently to provide a structurally sound bridge. Selection of the type of bridge designed will depend on the use and budget of the project.
Truss Bridges for Pedestrian Use
When designing a pedestrian bridge, the three main types of bridges to select from are beam bridges, truss bridges, and suspension bridges. Truss bridges are often chosen because of their strength and because the triangular shapes are aesthetically pleasing.
There are numerous truss bridge designs available that you can select for a pedestrian bridge. The image below shows a few of them.
Truss Bridge Benefits
Even though the most popular reasons for selecting a truss bridge are its strength and design appearance, many of its other benefits can help you determine if this design is best for your project. At Areté Structures, we design pedestrian bridges using FRP. A few of the advantages of FRP truss bridges include:
- Considerable Span Length – From 25-100 feet
- Works in Almost Any Location – The versatile design allows you to build this bridge virtually anywhere (if it can be supported).
- High Strength – Can be designed to accommodate the weight of pedestrians, bicyclists, and lightweight vehicles.
- Affordable Design Option – Requires minimum materials to build, and depending on the material selected, can be transported and installed easily.
What an Areté Structure’s Truss Bridge Design Looks Like
At Areté Structures, we design truss bridges using FRP material. FRP truss bridges are lightweight and can be installed without heavy equipment, making them the ideal solution for remote locations.
In 2018, we designed, fabricated, and supplied eight pony truss bridges for the Oregon Parks and Recreation Department. These bridges were designed to support pedestrians, bicycles, and trail maintenance vehicles. Learn more about this project here.