Effect of Panel Thickness on the Uniaxial Tensile Behaviour of Glass Textile Reinforced Concrete

Generally, it is known that the tensile strength of plain concrete decreases with the size of the element, which is attributed to the higher probability of having larger and more microstructural defects in larger elements or the effect of the propagation of the fracture process zone. There is limited information on the size and scale effects on the strength of strain-hardening cement based composites such as Textile Reinforced Concrete (TRC), which are beneficial for developing structural sections that are allowed to crack in a stable manner before failure. The size effect on tensile response of TRC is necessary for rational design and implementation of large-scale applications. In the current study, composite panels of different thickness (i.e., 10, 20, 40 mm) were fabricated using a cementitious matrix and coated E-glass textiles reinforcement; four layers of textile were used in all the panels. The specimens were monotonically loaded under direct tension in accordance with RILEM TC232. The specimens have shown a slight reduction in the first crack stress with increasing thickness, as can be explained based on statistical scale effects. Also, the overall tensile response transitions from strain-hardening to strain softening behaviour as specimen thickness increases. More interestingly, the number of cracks decreased with increasing size at any given strain. Further, DIC analyses reveal that the crack pattern and crack widths are significantly affected by the panel thickness.