Earth Month: UMD professor researching ways to make concrete more sustainable

UMD Professor of Civil Engineering Andrea Schokker is researching ways to make concrete more sustainable.

She is a structural engineer who focuses on concrete in buildings and bridges.

Schokker says cement is the element that makes modern concrete pretty unsustainable.

“So when we make cement, we basically — I’ll make it simple and just say we burn limestone. And that lets off CO2,” she said.

Some of the carbon comes from the energy to make the cement and some is just from the limestone itself.

There’s an important distinction between cement and concrete: Cement is the gray powder, and concrete is the hard stuff.

“If the cement is the culprit, there’s actually only about 10 percent of a concrete volume is cement. The rest is rocks and sand and water and some air bubbles,” Schokker said. “So the place that we need to tackle is the cement.”

She said concrete is the second most widely used material on Earth after water.

“But because of that, that means if we do things better, it really impacts our CO2 and helps us reduce that amount, which is good for the globe, obviously,” Schokker said.

UMD is doing some research into replacing cement with waste materials like byproducts from making steel or waste glass.