News @ the Beach

Cal State Long Beach Professor Says Textile Waste Not a Waste at All

LONG BEACH, Calif. (Jan. 16, 2014) — Some look at textile waste and think of disposal. Yu-Fu Ko, a member of the faculty in the civil engineering and construction engineering management department at California State University, Long Beach (CSULB), looks at textile waste and thinks of opportunities.

Ko’s recent research focuses on seismic retrofitting of existing structures with an eye to using textile waste to support civil infrastructures.

“I’m looking at how they might be used to reinforce concrete structures such as buildings and bridges,” said Ko. “If the preliminary research results were successful, it could be applied to retrofit earthquake-damaged structures in the future. In current practice, carbon fiber reinforced polymer composites (CFRPs) are used to retrofit buildings and bridges. But making these reinforcing fibers can be hazardous. Workers who make carbon fibers breathe in the materials. That’s not good. Plus, carbon fibers are expensive. I hope, by mixing textile waste with bio-derived resin matrix, they will deliver the equal strength of CFRPs at a reduced environmental impact.”

Based on Ko’s recent research, it will be doable and practically feasible in the future. Not only would textile waste patch up an aging infrastructure, it would offer a substitute for diminishing global resources.

“The material diminishing the fastest is timber,” he said. ”I see less every year. The same is true for reinforced concrete and steel. Typical buildings and bridges today still use all these materials. That won’t be the case in the future.”

When he teaches undergraduate and graduate students, Ko stresses the potential for the use of new materials.

“If you inject carbon nanotubes into a structure, it can multiply the strength of the original structure,” he said. “Look at the process of filling concrete with rebar. The carbon nanotubes play the same role as the rebar. It offers additional reinforcement. In decades, there will be limited resources to make rebar. In addition, the carbon nanotubes offer many times the strength offered by rebar reinforcement. We are talking about superstructures in the future.”

Developing new computational modeling is also Ko’s research focus. He uses computational algorithms to perform the numerical tests, which will be calibrated by performing the mechanical tests that could characterize the materials used in the analysis and design of buildings, bridges and other infrastructures.

“I work to develop new computational programs so an engineer or a student could input numbers and parameters and immediately estimate the mechanical properties of the materials used in their daily design,” he said.

Ko believes that it is very important to understand the materials used in modern construction at both microscopic and nanoscopic scale. Also an applied mechanics researcher, he studies the material’s behaviors both mechanically and numerically.

“It is important to come up with the right equations and computer programs so that engineers or students could understand the material’s fundamental parameters,” he said. “With these kinds of studies, we can make predictions about the material’s behaviors and we can use these data to analyze and design for buildings, bridges, infrastructures, cars, airplanes, etc.”

Prior to joining CSULB, Ko was a postdoctoral researcher and lecturer at UCLA as well as a senior structural design engineer at Englekirk and Sabol Consulting Structural Engineers, Inc. Ko is a registered Professional Civil Engineer in California.

“New materials are always under development,” said Ko. “New materials would change current analysis and design philosophy of structures. If you understand the material behaviors at the microscopic and nanoscopic scale, you can understand the macroscopic behaviors of the materials and easily utilize these materials. The engineering students need to know both microscopic and nanoscopic and macroscopic behaviors of materials. It is important to provide engineering students with that knowledge in their education.”

Ko feels his theoretical and practical experiences help him in the classroom. “CSULB offered me many opportunities in teaching and research to guide engineering students to learn both theories and practical experiences,” he said. “CSULB engineering students will be very well prepared for the competitive job markets.”