摘要
The microcapsule-enabled cementitious material is an appealing building material and it has been attracting increasing research interest.By considering microcapsules as dissimilar inclusions in the material,this paper employs the discrete element method(DEM)to study the effects of loading rates on the fracturing behavior of cementitious specimens containing the inclusion and the crack.The numerical model was first developed and validated based on experimental results.It is then used to systematically study the initiation,the propagation and the coalescence of cracks in inclusion-enabled cementitious materials.The study reveals that the crack propagation speed,the first crack initiation stress,the coalescence stress,the compressive strength and the ultimate strain increase with the loading rate.The initiation position,the propagation direction,the cracking length and the type of the initiated cracks are influenced by the loading rates.Two new crack coalescence patterns are observed.It is easier to cause the coalescence between the circular void and a propagating crack at a slow loading rate than at a fast loading rate.
