ECI Digital Archives

Title

PVA fiber/matrix interface characterization in alkali-activated slag/fly ash system: Effect of SiO2/Na2O ratio

Authors

Shizhe Zhang, Delft University of Technology, NetherlandsFollow
Bahman Ghiassi, Delft University of Technology, Netherlands
Guang Ye, Microlab, Section Materials and Environment, Faculty of Civil Engineering and Geosciences, Delft University of Technology, The Netherlands

Conference Dates

May 27-June 1, 2018

Abstract

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.

Recommended Citation

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). https://dc.engconfintl.org/geopolymers/33