Green and durable engineered cementitious composites (GD-ECC) with recycled PE fiber, desert sand, and carbonation curing: Mixture design, durability performance, and life-cycle analysis

Abstract

While engineered cementitious composites (ECC) exhibit superior properties to conventional concrete, using expensive synthetic fibers and large volumes of cement results in a higher cost and carbon footprint. In this study, in order to enhance material sustainability, a green and durable ECC (GD-ECC) was developed with greener raw ingredients, especially recycled polyethylene (PE) fiber and desert sand, as well as with carbonation curing. The durability properties of GD-ECC were experimentally evaluated, followed by a life cycle assessment of a potential bridge deck application to verify the life-cycle reduction in the carbon footprint of civil infrastructure. The results show that the developed GD-ECC exhibits a tensile strength of 3.3 MPa, tensile ductility of 7.7%, and tight crack width of less than 60 µm. The embodied carbon and cost of GD-ECC are comparable to that of conventional concrete due to the recycled fiber and desert sand. Besides, the reinforced GD-ECC exhibited superior corrosion resistance and was predicted to have a service life double that of reinforced mortar. Finally, the life-cycle assessment of a potential bridge deck application indicated that the life-cycle material cost and carbon footprint were reduced by half when replacing conventional joints with GD-ECC link slabs.