Distributed cracking mechanisms in textile-reinforced concrete under high speed tensile tests

Distributed cracking mechanisms in textile reinforced concrete (TRC) subjected to high speed loads and temperature variations were studied using digital image correlation (DIC) analysis and finite difference modelling. Three different TRC composites made of laminated AR glass, warp-knitted AR glass and polypropylene were used. Both plain textile and TRC specimens were tested at a nominal strain rate of 100 s⁻¹ at the temperature range of −30–80 °C. The non-uniform distribution of longitudinal strain in TRC systems was divided into three distinct zones of localization, shear lag, and uniform strain and the strain distribution in each zone was quantitatively measured. Tensile strength and postcrack stiffness decreased in various TRCs as the temperature increased with the highest tensile strength of 38.1 MPa, work-to-fracture of 46.6 J, and postcrack stiffness of 459.7 MPa recorded for the warp-knitted AR glass TRC specimens at −30 °C. A finite difference model was used to simulate the experimental crack spacing and stress–strain behaviors as well as the degradation in postcrack stiffness as a function of interfacial bond strength. The experimentally observed crack patterns and failure modes in TRC systems agreed with the numerical simulations and the measurements of slip zone size using DIC.