WEST LAFAYETTE, Ind. (AP) — Purdue University researchers have developed a new high-performance concrete that engineers say should help bridges last longer and reduce maintenance costs.

Professor Jason Weiss says testing shows the internally cured concrete is less prone to cracking and damage caused by deicing salt.

Internal curing relies on water pockets that are formed by using small porous stones inside the concrete to replace some of the sand in the mixture. That enhances the reaction between the water and cement.

Purdue worked with the Indiana Department of Transportation to develop specifications for the new material to be used on four bridges this year. The first bridge using the new concrete will be on State Road 933 in St. Joseph County.

INDOT expects the new concrete to be used more widely in the future.