Experimentally validated multi-scale modelling scheme of deformation and fracture of cement paste

This paper presents a validation procedure of multi-scale modelling scheme by making, testing and modelling deformation and fracture of cement paste beam at sub-meso scale (between micro and meso scale). Miniaturized three-point bending testing concepts were adopted. Cement paste beams with a cross-section of 500 μm × 500 μm were fabricated using a micro dicing saw and subjected to bending using nanoindenter. Simultaneously, fracture behaviour of the same size specimens was predicted by a microstructure informed multi-scale lattice fracture model in which input microstructures are obtained by X-ray computed tomography at two scales (micro and sub-meso). Uncoupled upscaling approach was used to relate the material's mechanical behaviour at sub-meso scale with the microstructures at lower scale. A good agreement between experimental and numerical results was observed which shows that starting from micro scale and with relatively simple mechanical considerations it is possible to correctly reproduce behaviour at upper scale.