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There are several timeless designs that have been used in bridge building for decades. However, there are few more iconic than the truss bridge. In the 1800s, America was the leader in truss bridge design, though older constructions used wood. The design is vintage Americana, but it’s become modernized.
Today, truss bridges are used as an effective bridge construction option. Although one thing has changed: steel is the primary component in new truss constructions.
Let’s discuss why we use steel truss bridge design for many of our new constructions.
Truss bridges are formed with a structure of connected elements that form triangular structures to make up the bridge. Trusses are the triangles that connect to the top and bottom cord and two end posts.
The trusses make up reinforcement for the bridge that even the load-bearing across the structure. Furthermore, the truss dissipates the load through the structure so the middle of the beam experiences less compression and tension. As you will see later, there are several variations of the truss, but it starts with a top and bottom cord and a series of trusses.
Even the earliest wood truss bridges were built to distribute weight evenly. With this intention in mind, bridges could be built for larger loads. Overall, this makes this bridge design a very strong and dependable option. With steel construction, truss bridges can take on the traffic of today.
What makes truss bridges relevant more today than ever is their effective use of materials. Keep in mind, less materials means easier construction and less money spent. Already, our bridge construction uses recycled steel that is lightweight and has been certified for Bridge Fabrication — Advanced (Major) by the AISC.
In fact, each piece is constructed with a definite purpose for truss bridge construction. This way, the construction and use of each steel piece are perfect for the bridge.
Because of the simplicity of truss bridge designs, they are often a great fit for accelerated bridge construction. In order to improve construction time, each steel piece can be quickly pieced together.
If considering the full cost of material and labor, truss bridges save builders thousands of dollars. Not to mention the long-term savings from building a long-lasting, durable bridge.
While truss bridges are great for short spans, what makes them versatile is their ability to go long distances and still support large loads. With the polygonal design of the truss, it’s possible to cover long distances.
In particular, truss bridges can be needed in areas with extreme weather. Despite the harsh weather, with great structural engineering, our truss bridges are prepared to last even the worst storms for decades to come. When it comes to crossing a treacherous area, truss bridges can be built to keep communities connected.
While a truss bridge may seem simple, they are actually quite intricate and require complex engineering and design. Because the weight must be distributed away from the center beam, each truss must be optimally engineered to distribute the weight. Without attention to detail in the engineering design, the truss design will not be nearly as effective.
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