New Concrete Joints Mimic Adhesive Properties of Mussels

Researchers at the University of Delaware have created new, durable adhesive joints for concrete structures by mimicking mussel adhesion. Photo courtesy of University of Delaware.

A University of Delaware (Newark, Delaware, USA) professor has received a National Science Foundation (NSF) CAREER award to create new, durable adhesive joints for concrete structures. Jovan Tatar, an assistant professor of civil and environmental engineering and an affiliated faculty in the Center for Composite Materials, drew inspiration from shellfish—mussels specifically—to develop a resilient adhesive option for affordable housing and next-generation infrastructure.

According to Tatar, one persistent problem with existing concrete adhesives is that they lose their bonding power when exposed to moisture. This is an obvious problem given how often concrete structures such as bridges and building exteriors are exposed to water. To that end, Tatar looked to fields such as the automotive and aerospace industries that use special adhesives to accelerate production, prolong product life, reduce stress concentrations, and control maintenance costs.

“Similar benefits could be attained in the structural engineering field with adhesives that are specifically designed to withstand the environmental stressors and structural demand in concrete structures,” he says. “This need in the field has inspired me to seek nature-inspired solutions for durable adhesive bonding to concrete.”

Tatar was intrigued by the ability of mussels to not only establish and maintain adhesion underwater, but to do so on substances made of minerals similar to those found in concrete. This ability to adhere in moist conditions is especially critical for concrete structures where moisture is a significant concern, such as along coastlines. According to a recent National Institute of Standards and Technology report, externally bonded fiber-reinforced polymer (EBFRP) composite retrofits strengthen reinforced concrete structures by making them more resilient to natural disasters and decay.

“By enabling durable adhesive bonding to concrete, this project will improve the durability of EBFRP retrofits, which addresses two important needs: the National Earthquake Hazards Reduction Program’s call to improving retrofit technology; and the National Academy of Engineering’s Grand Challenge to restore and improve urban infrastructure,” says Tatar.

Tatar argues that increased innovation in the field of joint adhesives, along with prefabricated structural components and 3D-printed concrete, could help the construction industry keep pace with rapid urbanization and meet the projected demand for new buildings built using sustainable resources.

“The booming urban population will also generate unprecedented demand for affordable housing and next-generation infrastructure to support sustainable growth,” says Tatar. “To meet the needs of modern society, the construction industry must substantially accelerate production which will likely be possible through prefabricated construction and additive manufacturing.”

“I envision fundamental advances in the understanding of bio-inspired adhesion to concrete will enable the development of durable adhesive joining techniques that support innovation and increase productivity in the construction sector,” adds Tatar.

Source: University of Delaware, www.udel.edu.