In 2007, the I-35W Bridge in Minneapolis collapsed killing three people and injuring over 140 others. The collapse was caused due to a design deficiency that led to gusset failure during construction.

A team of researchers at the University of Delaware used this and other similar examples as motivation for their latest research. They began developing a structural monitoring system using carbon nanotube glass fiber composites that would act as a continuous conductive skin on beams of concrete. The team received a $300,000 grant from the National Science Foundation, which will be dispersed over a three year span to faculty members Thomas Schumacher and Erik Thonstenson.

Thonstenson and Schumacher chose carbon nanotube composites for what they called the “smart skin” of structures. Initially, carbon nanotubes hybrid glass fiber composites worked as a conductive skin when attached to small concrete beams. “The skin seemed to be very sensitive to any changes in strain and any aggravation due to damages,” they say.

The fact that the carbon nanotubes have the ability to fuse with to composites to form advanced composites structures gives it a completely different functionality. Therefore, the hybrid fiber composites sensors can strengthen damaged structures.