This study examines the impact of microfibre inclusion on the tensile properties of cement paste at the microscale through both experimental and simulation approaches. Micro-cubes containing vertically aligned microfibres were fabricated using cement pastes with varying water- to-cement (w/c) ratios,…
This study examines the impact of microfibre inclusion on the tensile properties of cement paste at the microscale through both experimental and simulation approaches. Micro-cubes containing vertically aligned microfibres were fabricated using cement pastes with varying water- to-cement (w/c) ratios, ranging from 0.3 to 0.5. These specimens underwent a splitting test using a nano-indenter with a wedge tip, and the results were compared to those of micro-cubes without fibres. Mechanical properties, including load capacity, peak deformation, stiffness, and fracture energy, were analysed. The findings indicate that fibre inclusion reduced the splitting tensile stress and modulus of the micro-cubes across all w/c ratios. Additionally, the influence of fibre inclusion became more pronounced with higher w/c ratios, likely due to a more porous interfacial transition zone (ITZ) at these higher ratios. To complement the experimental work, a lattice model with a simplified microstructure, comprising paste, fibre, and ITZ, was developed to simulate the fracture behaviour of the micro-cube under indentation splitting. The simulation results were in strong agreement with the experimental data, facilitating the determination of the mechanical properties of the ITZ.