PVA fiber/matrix interface characterization in alkali-activated slag/fly ash system: Effect of SiO2/Na2O ratio
May 27-June 1, 2018
Bond behavior between fiber and matrix plays crucial role in the nonlinear properties and performance of fiber reinforced composites. However, the available information on the fiber/matrix interface properties in composites made of alkali-activated materials is still quite limited which have hindered the scientific design and production of these materials.
This study presents an experimental investigation for evaluating the bonding characteristics of PVA fiber/alkali-activated matrix interface by performing single fiber pullout tests. Four SiO2/Na2O ratios (0.8, 1.0, 1.2 and 1.5) within the alkaline activator were used for mixture preparation to investigate the effect of chemistry of the matrix on the bond performance. All the specimens were tested after 28-days curing. The interface characteristics including chemical bonding energy, interfacial frictional force as well as the slip-hardening properties were determined from the fiber pullout tests. It was found that the chemical bonding energy increased initially and then decreased with increment of SiO2/Na2O ratio, indicating an optimal alkaline activation condition at SiO2/Na2O ratio of 1.0-1.2. At the same time, the interfacial frictional strength and the slip-hardening properties did not change significantly by increasing the SiO2/Na2O ratio. These changes with SiO2/Na2O ratios were further correlated with the chemical nature of the reaction products to provide preliminary insight into the interfacial bonding properties of PVA fibers to the alkali-activated slag/fly ash matrices.
Shizhe Zhang, Bahman Ghiassi, and Guang Ye, "PVA fiber/matrix interface characterization in alkali-activated slag/fly ash system: Effect of SiO2/Na2O ratio" in "International Conference on Alkali Activated Materials and Geopolymers: Versatile Materials Offering High Performance and Low Emissions", J. Provis, University of Sheffield C. Leonelli, Univ. of Modena and Reggio Emilia W. Kriven, Univ. of Illinois at Urbana-Champaign A. Boccaccini, Univ. of Erlangen-Nuremberg A. Van Riessen, Curtin University, Australia Eds, ECI Symposium Series, (2018). http://dc.engconfintl.org/geopolymers/33