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Textile Waste Not A Waste At All

Published: December 17, 2014

Some look at textile waste and think of disposal. Civil Engineering and Construction Engineering Management’s Yu-Fu Ko looks at textile waste and thinks of opportunities.

Ko’s areas of research interest and expertise include micro/nano-mechanics modeling of heterogeneous composite materials, micromechanical damage mechanics modeling and associated applications, damage assessment and experimental mechanics of structural materials, nonlinear/linear structural dynamic analysis of structures subjected to earthquake motions, finite element method, code-based and performance-based structural design of structures, and seismic retrofitting of existing structures. Ko also performed various experiments to study the mechanics of materials, including the ultrasonic nondestructive test, the direct tension/compression tests of concrete subjected to environmental attack, and experimental fracture mechanics.

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, a member of the university since 2009. “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/graduate students, Ko stresses the potential for the utilization of new materials. “For example, if you inject carbon nanotubes into a structure, it can multiply the strength of the original structure by many times,” he explained. “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 the State of California who received his B.S. degree in Structural Engineering from National Taiwan University of Science and Technology in 1997 as well as his M.S. and Ph.D. both at UCLA in 2001 and 2005, respectively.

“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/nanoscopic scale, you can understand the macroscopic behaviors of the materials and easily utilize these materials.

“The engineering students need to know both microscopic/nanoscopic and macroscopic behaviors of materials,” he added. “It is important to provide engineering students with that knowledge into 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.”