“…However, due to low fracturing strain capacity of conventional FRPs [around 1.5% for carbon FRP (CFRP), 2% for glass FRP (GFRP), and 3% for aramid FRP (AFRP)], the fiber materials tend to fail sooner due to fiber breakage, which causes a loss of confinement and hence the load-carrying capacity as well as the ductility potential. New fiber materials, such as polyacetal fiber (PAF), polyethylene naphthalate (PEN), and polyethylene terephthalate (PET), have properties of large fracturing strain and low stiffness in comparison to aramid, carbon, and glass fibers (Jirawattanasomkul, Dai, Zhang, Senda, & Ueda, 2013). Previous studies (Anggawidjaja, Ueda, Dai, & Nakai, 2006;Dai, Bai, & Teng, 2011;Dai, Lam, & Ueda, 2012) proved that concrete or RC members wrapped by PET and PEN fiber sheets with large fracturing strain could efficiently enhance the ductility of concrete or RC members, regardless of their low stiffness.…”