Size and Boundary Effects During Failure in Quasi-brittle Materials: Experimental and Numerical Investigations

Three-dimensional numerical evaluation of the progressive fracture mechanism of cracked chevron notched semi-circular bend rock specimens

“…The linear elastic fracture mechanics (LEFM), in which all the fracture process is assumed to occur in one point, might not be 20% peak force 40% peak force 60% peak force 80% peak force 100% peak force post 50% peak force suitable for analyzing failure of brittle solids with a large FPZ. Indeed, the size of the FPZ is controlled by the local heterogeneity in the material as well as by the specimen geometry and the stress conditions [50], in accordance with our numerical simulation. In this study, the FPZ in CCNSCB sample with b = 0.8 is smaller than that of a sample with b = 0.5 or 0.3, comparing the AE activities.…”

“…Researchers have reported that the FPZ can induce size effect of fracture toughness and result in the variation of measured toughness in a wide range for the specimens with different sizes [47][48][49][50]. The linear elastic fracture mechanics (LEFM), in which all the fracture process is assumed to occur in one point, might not be 20% peak force 40% peak force 60% peak force 80% peak force 100% peak force post 50% peak force suitable for analyzing failure of brittle solids with a large FPZ.…”

Modeling of the quasibrittle fracture of concrete at meso-scale: Effect of classes of aggregates on global and local behavior

“…Therefore, the homogenization process of mortar leads to a loss of information at small length scales where the microstructure seems to play an important role. Moreover, the numerical results could be analyzed with the same Acoustic Emission (AE) analysis process [31], considering an analogy between recorded events from AE (corresponding to micro-crack nucleation) and numerical damaged elements [32]. It is on the basis of this latter remark that posttreatment results are achieved (Figs.…”

A damaging beam-lattice model for quasi-brittle fracture

“…The model developed here, is built to be suitable for any quasi-brittle material simulation. Among quasi-brittle materials, concrete is subject of numerous studies available in literature [57], [58], [59], [60], [61], [62] and is chosen here in or-410 der to test the model in various fracture modes. Indeed, the main characteristics of the concrete failure under compressive and tensile loading are well-known and are here simulated to evaluate the relevance of the damage cohesive beam model.…”