Tension-shear characteristics, cost and environmental impact of polyethylene fiber reinforced engineered cementitious composites: The role of fiber content

Engineered cementitious composites (ECC) tailored with fibers is famous for distinguished tensile ductility and tight crack width control capacity. The ECC material of the structural members may be in the state of tension-shear stress, e.g. ECC in the shear span of beams. Accordingly, this research focuses on the characteristics of ECC with diverse polyethylene (PE) fiber contents (0.5%, 1.0%, 1.5% and 2.0%) under tension-shear loading. The basic characteristics of PE-ECC subjected to uniaxial tension, uniaxial compression and pure shear were tested. The tension-shear behaviors of PE-ECC subjected to various loading angles were investigated by an elaborately designed test fixture. PE-ECC with the fiber content of over 1% exhibited obvious multiple-cracking phenomenon when subjected to tension-shear loading, and crack number decreased as loading angle continued to raise. The tension-shear strength for PE-ECC was enhanced by increasing fiber content. The failure criteria stemmed from the octahedral stress space (linear function) or stress invariant can be applied for depicting the failure laws of PE-ECC. Additionally, cost comparison and environmental impact evaluation indicated that fiber cost accounted for a significant higher proportion of the total cost (over 36%), while the proportion of fiber carbon footprint to the entire carbon footprint was low (less than 12%). This research will provide a useful assistance in understanding the tension-shear behaviors of PE-ECC and further facilitating its structural applications.