Steel vs. Concrete: Which is More Environmentally Friendly?

Weathering Steel Bridge Sustainability

Steel vs. Concrete: Which is More Environmentally Friendly?

Concern over “greener” or more “environmentally-friendly” choices has never been greater, especially in bridge construction. Sustainability revolves around three pillars–social, environmental, and economic. Essentially, a bridge build should consider the environment, but also improve the economy and social situation of the area the bridge is built in: 

Will the bridge serve future generations? Are the raw materials selected environmentally friendly? Will the outcome of the project be equal or higher in value than the cost it took to make it? 

The potential impact on the environment is an important consideration when selecting raw materials for a bridge, according to the Short Span Steel Bridge Alliance. Bridge owners are often left to decide between steel or concrete with inadequate information to evaluate the sustainability of the materials.

Evaluating bridge sustainability 

To solve this problem, the University of Wyoming conducted a study and developed a methodology to evaluate the life cycle sustainability of two functionally-equivalent, nearly-identical, two-lane steel and concrete rural bridges. The two bridges were evaluated based on four criterias: 

  1. Embodied carbon emissions of materials and emissions from equipment
  2. Embodied energy of materials, and energy consumption from equipment
  3. Waste management and recyclability
  4. Life cycle cost

Let’s look at the results they reported…

Steel vs. concrete: Which material is more sustainable?

In short, steel is a more sustainable raw material choice for bridge construction. The results proved that over the life cycles of the two bridges, the concrete bridge…

  • Emitted 26.3% more embodied carbon
  • Consumed 8.7% more energy
  • Recycled 17.8% less material (at the end of its service life when compared to the steel bridge)
  • Cost 23% more than the steel bridge


The sustainability of steel bridges

This report further proves that steel is a sustainable material choice for bridge construction. Not only is steel the most-recycled material in the word, but steel bridges also cause minimal disruption to the construction site, reduce construction time and provide extremely long service lives. Plus, because steel bridges can be strengthened and adapted to increase loadings or widen roadways, they will continue to serve future generations. It’s one of the many reasons bridge owners are looking to steel to repair our nation’s infrastructure. 

Choose weathering steel for bridge construction 

Weathering steels, often referred to as Cor-ten®, are a family of ASTM specifications and several trademarked specifications exhibiting similar corrosion-resistant properties. Ultimately, the high-strength, low-maintenance (no initial painting nor future maintenance painting is required!), and cost-effective benefits that weathering steel offers make it a sustainable solution for bridge construction

ASTM A847 hollow structural sections are commonly recommended for bridge construction. Weathering steel Hollow Structural Sections (HSS) add strength and beauty to any steel structure. Plus, with weathering steel hollow structural sections, you need less steel to do the same job.

Contact Central Steel Service for ASTM A847 Hollow Structural Sections

ASTM A847 hollow structural sections are commonly recommended for bridge construction. Central Steel stocks high-strength, corrosion-resistant steel pipe and tube in a variety of sizes. Contact us today to speak with an experienced sales representative about your project.