What is the main reason steel is used in bridge construction?

What is the main reason steel is used in bridge construction?

• A. It is very malleable.
• B. It has a high strength to weight ratio.
• C. It is highly resistant to corrosion.
• D. It is one of the hardest materials.

Answer: (B)

The main idea is that steel gives a very high strength relative to its weight. This means you can carry large loads and resist bending and tension without making the structure extremely heavy. In bridges, that strength-to-weight advantage lets you span longer distances, use lighter, slimmer members, and reduce the weight that foundations must support. That translates into cost savings, easier fabrication and erection, and better performance under dynamic and fatigue loads because steel can deform a bit and absorb energy without sudden failure. While corrosion resistance and hardness are different properties, and malleability is about shaping the material, the key factor for why steel is used in bridges is its high strength-to-weight ratio.

The main idea is that steel gives a very high strength relative to its weight. This means you can carry large loads and resist bending and tension without making the structure extremely heavy. In bridges, that strength-to-weight advantage lets you span longer distances, use lighter, slimmer members, and reduce the weight that foundations must support. That translates into cost savings, easier fabrication and erection, and better performance under dynamic and fatigue loads because steel can deform a bit and absorb energy without sudden failure. While corrosion resistance and hardness are different properties, and malleability is about shaping the material, the key factor for why steel is used in bridges is its high strength-to-weight ratio.