March Newsletter: Page 3
Feasibility Study of Concrete Reinforced with Recycled Fiber Reinforced Polymer Rebar
Fiber-reinforced polymer (FRP) rebar is a rapidly advancing reinforcement technique for concrete structures that are subjected to impact and high-cycle dynamic loading. The high strength, fatigue and corrosion resistance makes FRP an ideal material for reinforcement of railroad sleepers.
Professor Sulapha Peethamparan and graduate student Robert Thomas from the Department of Civil and Environmental Engineering, and Professor Ajit Achuthan from the Department of Mechanical and Aeronautical Engineering, have teamed up with Composite Systems Technologies (Massena, NY), a local composite manufacturer, to evaluate the feasibility of using fully-recycled FRP rebar in concrete rail structures. The project is supported by Composite Systems Technologies and CAMP.
Figure 4: A hollow sleeper cross section with reinforcement at mid-height of the bottom flange.
The flexural response of hollow pilot-scale sleepers (shown in Figure 4) with a span length of 36 inches was evaluated for beams reinforced with steel rebar, commercially available (non-recycled) FRP rebar, and fully-recycled rebar processed by Composite Systems Technologies. The beams were cast with a hollow cross-section for reducing the weight and increasing the efficient material usage.
Figure 5 shows the resulting flexural response of three beams with identical reinforcement area. The steel-reinforced concrete beam exhibited higher flexural strength compared to FRP –reinforced concrete beams due to the higher strength of the steel reinforcement, which is approximately two times the strength of FRP rebars. Interestingly, the recycled FRP-reinforced beam stiffness and strength were nearly identical to the commercial FRP-reinforced beam.
Figure 5: The flexural response of hollow sleeper beams under four-point bending shows nearly identical behavior between recycled and commercial FRP reinforcement.
More detailed investigation into the bond development and cyclic load resistance of this type of beam are necessary prior to full-scale implementation and testing, but it has been shown that the locally-manufactured recycled FRP rebar is as effective as FRP rebar that is currently available on the market. Though the flexural strength of the FRP rebar reinforced concrete is marginally lower than the concrete reinforced with the same volume of steel, the advantages in terms of lower maintenance cost, lower weight and longer design life may make it a very promising solution.
CAMP and CACT Hold the Second Joint Spring Symposium
The Center for Advanced Materials Processing (CAMP) at Clarkson University and the Center for Advanced Ceramic Technology (CACT) at Alfred University held their second joint Spring Symposium. The event took place at the Double Tree Hotel in Rochester, New York on March 11&12, 2013. This Symposium covered a broad range of research activities and gave industrial scientists and engineers a chance to interact with CAMP / CACT faculty on their expertise. Richard Schmachtenberg (Senior Vice President, Consumables Development & Manufacturing Group, Xerox Corporation) delivered the Keynote Address titled “Landscape of Bio-based and Sustainable Materials.” This successful meeting was both enlightening and stimulating and included presentations by university and industrial representatives.