Glass-fibre-reinforced mortar: study of fresh behaviours based on average water film thickness and fibre/cement ratio

Abstract

Using glass fibres to reinforce cement-based materials (CBMs) has great effects on their fresh behaviours. In addition, the impact of water – particularly the average water film thickness (AWFT) – on the fresh properties of CBMs cannot be ignored. However, the combined effects of glass fibre content and AWFT on the fresh characteristics of CBMs are not satisfactorily understood. Therefore, in this study, mortar mixtures with varying fibre/cement (f/c) ratios and water/cement ratios were prepared and subjected to mini V-funnel tests, mini slump flow tests, stone rod adhesion tests, sieve segregation tests and wet packing tests. The AWFTs of the mortar mixes were also determined. The experimental results indicated that the f/c ratio (fibre content) had a noticeable influence on the fresh properties, packing density and AWFT. Modelling analysis demonstrated strong correlations of the workability, flowability, adhesiveness and cohesiveness with the f/c ratio and the AWFT. In other words, both the AWFT and the fibre content collectively serve as governing factors influencing the fresh behaviours of mortars reinforced with glass fibre.