Title: Tensile Strain-Hardening Behavior of Polyvinyl Alcohol Engineered Cementitious Composite (PVA-ECC)
Author(s): Victor C. Li, Shuxin Wang, and Cynthia Wu
Publication: Materials Journal
Appears on pages(s): 483-492
Keywords: cementitious; crack; strain.
A high-performance polyvinyl alcohol fiber-reinforced engineered cementitious composite (PVA-ECC) for structural applications has been developed under the performance-driven design approach. Fiber, matrix, and fiber/matrix interfacial properties were tailored based on micromechanics models to satisfy the pseudo strain-hardening condition. In this paper, the effects of fiber surface treatment and sand content on the composite performance were experimentally investigated. Results from uniaxial tensile tests show an ultimate strain exceeding 4%, as well as an ultimate strength of 4.5 MPa for the composites, with a moderate fiber volume fraction of 2.0%. The specimens reveal saturated multiple cracking with crack width at ultimate strain limited to below 100 mm. The underlying reason of the distinctly different tensile behavior between normal fiber-reinforced concrete and PVA-ECC is highlighted by the comparison of complementary energy from their fiber bridging stress and crack opening curves.