Latest Issue of Science News


Solid Information: Chemical composition can determine concrete's durability

A new analysis reveals how damage progresses in concrete that's exposed to sulfate, a nearly ubiquitous compound. The work could lead to the design of concrete structures with improved durability, the report's author says.

Concrete is made with Portland cement, a powdery mixture of crushed limestone and clay or shale. When the cement is mixed with water and added to gravel and sand, the resulting slurry hardens into concrete.

Portland cement consists primarily of four minerals: tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite. The chemical reactions among these compounds and water form a glue that binds the gravel and sand.

Note: To comment, Science News subscribing members must now establish a separate login relationship with Disqus. Click the Disqus icon below, enter your e-mail and click “forgot password” to reset your password. You may also log into Disqus using Facebook, Twitter or Google.

This article is available only to subscribing members. Join SSP today or Log in.