Engineers from the University of Illinois Urbana-Champaign have created a test for predicting the durability of cement in mere minutes.

According to the engineers, the test measures how water droplets behave on cement surfaces via computer vision, promising to help propel the cement industry toward quick and automated quality control of materials.

Current tests used to measure the durability of cement used in infrastructure — which degrades over time thanks to exposure to deicing salts, freeze and thaw cycles and water ingress, for instance — examine the ability of cement paste to absorb water. One commonly used standard test, dubbed ASTM C1585, exposes a concrete sample featuring cement paste to water in the lab, with the idea being that the more porous a cement paste is, the more water it will absorb, thereby leading to the corrosion of rebar in reinforced concrete.

A technician will measure the so-called sorptivity of the cement by observing weight changes that occur over the course of several hours, the researchers explained.

However, the new test device reportedly predicts initial sorptivity via computer vision, which reveals how quickly a single water droplet is absorbed into the surface within the initial seconds or minutes.
“We performed the new test on more than 60 unique samples, and there’s a fairly good correlation between our results and the results from the conventional ASTM test method,” the researchers explained. “So we are now proposing our new testing method as an alternative to test the durability of cementitious systems in a few seconds.”

An article detailing the new device, “Rapid prediction of cementitious initial sorptivity via surface wettability,” appears in the journal NPJ Materials Degradation.

To contact the author of this article, email mdonlon@globalspec.com