Effects of different test setups on the experimental tensile behaviour of basalt fibre bidirectional grids for frcm composites

Fibre-reinforced cementitious matrix (FRCM) composites have been effectively used during the last ten years for the strengthening of existing concrete and masonry structures. These composite materials are made of medium-and high-strength fibre meshes embedded in inorganic matrices. Synthetic fibres are the ones that are currently the most used; however, natural fibres, such as basalt fibres, have recently been receiving growing attention. This work presents an extensive experimental study on the mechanical characterisation of a primed basalt fibre bidirectional grid. Fifty monotonic tensile tests on basalt grid strips were performed by varying different parameters, such as the dimension of the specimens, the clamping system, the measurement system and the test rate. Some of the tests were carried out using a video-extensometer to measure each specimen’s strain. The aim of the study was to find the most suitable setup for the tensile characterisation of basalt textiles, in particular, to prevent slippage of the samples at the gripping area and fully exploit the tensile capacity of the grid.