28 January 2022

Researchers from Rensselaer Polytechnic Institute in Troy, NY say they have developed a hemp‐based rebar reinforcing technology for cement construction.

Alexandros Tsamis, assistant professor of architecture and associate director of the Center for Architecture Science and Ecology, and Dan Walczyk, professor of mechanical engineering and director of the Manufacturing Innovation Center, say the hemp-based natural fiber-reinforced thermoplastic rebar could replace steel in concrete buildings and infrastructure projects, eliminating common problems with corrosion while extending the structures’ lifetimes.

Rebar is used to construct skeletal frameworks in conventional cement buildings to provide tensile strength, which concrete lacks.

Strong as steel

The research team said preliminary study of the material has shown strength characteristics comparable to steel, and potential for significant reduction in greenhouse gas emissions.

The research is among the first projects to come from Rensselaer’s new Institute for Energy, Built Environment, and Smart Systems (EBESS), an interdisciplinary initiative in design, engineering, and business. EBESS is developing a broad plan for a sustainable and economically viable hemp industry that can address issues related to climate change in the conventional built environment.

Technologies are probed

Rensselaer researchers say they are working on several innovative and cost‐effective hemp processing technologies which gave rise to the development of the hemp rebar.

Those projects include the development of decortication technology that can separate hemp fibers from the stem’s woody inner core without adversely affecting the materials’ mechanical properties; a sustainable degumming method; and new hemp bio-composite processing methods.

Rensselaer Polytechnic Institute is a private research university in Troy, New York.