Effect of Temperature on the Low-Velocity Impact Behaviors of Engineered Cementitious Composite

This paper was intended to investigate the effect of temperature on the low-velocity impact behaviors of engineered cementitious composite (ECC). Two kinds of commonly used chopped fibers, i.e., polyvinyl alcohol (PVA) fiber and polyethylene (PE) fiber, were applied to prepare PVA-ECC and PE-ECC, respectively. The tensile and compressive behaviors of PVA-ECC and PE-ECC were first investigated with different water-to-binder (w/b) ratios. As the w/b ratio increased from 0.25 to 0.35, it was found that the tensile cracking strength and ultimate tensile strength increased, whereas the ultimate tensile strain decreased gradually. The compressive strength of PE-ECC was higher than that of PVA-ECC with the same w/b ratio. The low-velocity impact tests of PVA-ECC and PE-ECC were conducted under different environmental temperatures in the range of -50 degrees C to 150 degrees C. For PVA-ECC, it was found that the maximum load increased whereas the maximum displacement decreased significantly with the decrease of environmental temperature. By contrast, PE-ECC was relatively insensitive to the environmental temperature and had a much higher energy-dissipation coefficient than PVA-ECC specimens under cold environments. It was concluded that PE-ECC is more applicable to be applied in cold environments. The microstructures of PVA-ECC and PE-ECC after impact tests were also analyzed, and the failure mechanisms were discussed accordingly. (c) 2023 American Society of Civil Engineers.