Crumble-proof concrete? Fungi could help it heal itself of cracks

“Our work is to explore a revolutionary self-healing concept in which fungi are used to promote calcium mineral precipitation to heal cracks in concrete infrastructure,” Congrui Jin, assistant professor of mechanical engineering at Binghamton University, told Digital Trends. “The fungal spores, together with their nutrients, will be added into concrete during the mixing process. When cracks appear and water finds its way in, the dormant fungal spores will germinate, grow, and precipitate calcium carbonate to heal the cracks. When the cracks are completely filled and ultimately no more water can enter inside, the fungi will again form spores. As the environmental conditions become favorable in later stages, the spores could be wakened again.”

Jin describes the material as low-cost, pollution-free, and sustainable. It’s also potentially much longer-lasting than other solutions used to temporarily paper over the cracks in aging concrete. Particularly in applications like nuclear power plants, where concrete is used for radiation shielding, it could be of vital importance.

“Nowadays, concrete has been the key construction material for reactor containment and biological shielding structures, which are essential components of the nuclear reactors in service worldwide for power generation,” Jin said. “In addition, cementitious grouts, mortars, and concrete are also often used to provide shielding and encapsulation of various radioactive waste materials from military, research, and power-generation applications. Some waste isotopes, as well as their decay products, will become a serious radiation hazard for hundreds of thousands of years, which requests exceptionally durable storage. Self-healing concrete is [therefore] particularly useful in such applications.”

A paper describing the research was recently published in the journal Construction and Building Materials.