During my internship, I noticed that some buildings used a combination of structural steel and reinforced concrete rather than relying on just one material. I wanted to understand how combining different elements of the materials helped create a stronger building and if it was significantly more advantageous than just using a single material.

Composite construction is a technique that lets steel and concrete work together to form a stronger structure by taking advantage of each material’s strength. Steel provides high tensile strength and high flexibility, while concrete offers high compressive strength, resistance to weather, and durability. One common example of this are composite columns. Composite columns are either made of steel tubes that encase concrete, or concrete that encases a steel bar. These columns, by combining the strengths of both structural steel as well as reinforced concrete, allow for buildings to be fire resistant, bear massive axial loads, and have high durability and strength. Engineers are able to combine the best parts of steel and concrete to create extremely strong structural elements to ensure buildings stay strong and stable. Click on the above video on using structural steels with reinforced concrete.

Many commercial buildings like office towers use composite flooring systems. Composite flooring techniques that combine steel and concrete allow for floors to be less thick, and therefore weigh less, to reduce the overall dead load of the building. These floors are able to take up less space without sacrificing durability and strength. Rather than having to choose between structural steel and reinforced concrete, engineers can turn to composite engineering to have the best of both worlds. Composite construction allows for buildings to have the flexibility and tensile strength of steel as well as the compressive strength and fire resistance of concrete, all while maintaining the durability of buildings to ensure that they are safe for consistent use.