Ultra-ductile engineered cementitious composite
Researchers at the University of Michigan Advanced Civil Engineering Materials Research Lab have developed an engineered cementitious composite (ECC) that is far less brittle than conventional concrete. Made with thousands of short, randomly placed coated microfibers, the ECC can withstand four times the tensile force of its standard counterpart. It also exhibits three hundred times the ductility of regular concrete, hence its popular nickname, bendable concrete.
Under sufficiently high tensile stress, ECC does experience cracking, but the cracks are microscaled—approximately the size of a human hair—and able to self-heal in the presence of air and water. The material also gives way to corroding and expanding reinforcing steel, a phenomenon that commonly causes failures in conventional reinforced concrete. Furthermore, ECC has self-sensing capabilities that allow it to report increased strain and developing structural problems.
Test ECC applications have been successfully installed on highways and high-rise buildings, and the Michigan researchers speculate that a roadbed constructed with ECC could expect a service life of one hundred years—four to five times the life of standard concrete pavement.
Contact: University of Michigan Advanced Civil Engineering Materials Research Lab, Ann Arbor, MI, USA.
For more information, see Transmaterial Next: A Catalog of Materials that Redefine Our Future