Concrete, Heal Thyself!

A press story from the University of Michigan is currently circulating on a bendable new engineered cement composite (EEC) with the capacity of healing its own fractures using only air and water.

In this video, U of M professor of Materials Science and Engineering Victor Li explains his new material. “Self-healing of crack damage," he says, "recovers any stiffness lost when the material was damaged and returns it to its pristine state. The material can be damaged and still remain safe to load.” The average crack, about half the width of a human hair, reacts with water and carbon dioxide from just "a handful of drizzly days" to form a compensatory scar of calcium carbonate, the stuff of sea shells and, after a few million years, limestone.

Li's material requires no rebar and so is impervious to corrosion. The expectation is that the material will dramatically extend the useful life of bridges and roads (Bill Cellini must be sweating bullets), which is a good thing, as it currently costs about three times that of current material (OK, now he's feeling better again.) It's also designed to offer substantially enhanced protection from concussive blasts. The hope is a chunk of the stimulus jackpot will be devoted to rebuilding bridges with the new EEC

Professor Li now turns his attention to his ultimate obsession, the development of an EEC trampoline.

more technical papers here.