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Thermal expansion is a problem every engineer must face.

Everyone talks about the weather, but it falls to civil engineers to actually do something about it. Weather and temperature affect everything we use, from car batteries to bridges. When temperature causes changes in structure, it's referred to as thermal expansion or thermal contraction, and it's a phenomenon. you have to carefully control for if you're building a bridge or a sidewalk.

Practical Engineering took a look at how the weather affects everything, even something as simple as walking down the street.

Intentional cracks in the sidewalk are a perfect example of how engineers deal with thermal expansion. By filling these gaps with a flexible material, the engineers create what's known as a "expansion joint," something that's meant to help a structure keep its form even with shifting temperatures.

Expansion joints come in all shapes and sizes, from clay bricks to molded rubber. Some forms of construction, like railways or air ducts, have specialized breather joints meant to deal with their unique thermal stresses. Copper is often seen as a good one-size-fits-all solution for an expansion joint, given its durability and ability to take a wide variety of forms.

Some researchers are looking at 3D printing to find a way to make a material that doesn't react to heat at all. That'd be a game changer in terms of large civil engineering projects. But until they do, expansion joints will fill the gaps the best they can.