A comprehensive experimental study on the role of matrix structure on the multiple cracking behavior of PVA-ECC

Abstract

In this study, the effect of W/B ratio and mineral additive types on the role of fiber–matrix synergy in PVA-ECC was comprehensively investigated with the aid of micro-mechanical design theory. The effects of rheological properties, failure cross-section fiber distribution, natural flaw size distributions on tensile performance were investigated, and the relationships among these parameters were researched. For maximum tensile stress, crack analysis were performed with DIC technique and crack width histograms were determined. Moreover, the relationships between tensile performance and compressive strength have been investigated. According to the results, it was determined that the combined effect of W/B ratio and mineral additive type in PVA-ECC had a significant effect on both the rheological and mechanical results, and their relationships were compared. Fiber distribution and flaw size distribution should also be considered together to explain the difference in tensile performance of different/same ECC mixtures. It has been determined that the current micromechanical theory PSH criteria are insufficient to provide saturated multiple crack behavior, and therefore need to be updated. In the investigation of crack pattern of ECC, crack width distribution rather than average crack width was found to be a more realistic approach.