Two-dimensional meso-scale finite element models with real aggregates are developed using images obtained by digital image processing to simulate crack propagation processes in concrete under uniaxial compression loading. The model is regarded as a three-phase composite material composed of aggregate, mortar matrix and interface transition zone (ITZ). Cohesive elements traction–separation laws ...

Differences in the dynamics of powder densification between eccentric and rotary machine were pointed out by compressing at different compression pressures microcrystalline cellulose, lactose monohydrate and dicalcium phosphate dihydrate and recovering the corresponding stress/strain data in both machines equipped to monitor punches displacement and compression forces. Heckel plots were then ob...

The mechanical strength properties of lumbar spine vertebrae are of great importance in a wide range of applications. Herein, through nanoindentations and appropriate evaluation of the corresponding results, trabecular bone struts stress-strain characteristics can be determined. In the frame of the present paper, an L2 fresh cadaveric vertebra, from which posterior elements were removed, was su...

A common feature of the outer layer of protective biological exoskeletons is structural anisotropy. Here, we directly quantify the mechanical anisotropy and fracture of an individual material layer of a hydroxyapatite-based nanocomposite exoskeleton, the outmost ganoine of Polypterus senegalus scale. Uniaxial compression was conducted on cylindrical micropillars of ganoine fabricated via focuse...

Abstract In this paper, a framework for the simulation of crack propagation in brittle and ductile materials is proposed. The derived by extending eigenerosion approach Pandolfi Ortiz (Int J Numer Methods Eng 92(8):694–714, 2012. 10.1002/nme.4352 ) to finite strains connecting it with generalized energy-based, Griffith-type failure criterion fracture. To model elasto-plastic response, classical...

Uniaxial and triaxial compression tests on steel fibre reinforced shotcrete (SFRS) have been used to quantify the elastic–plastic response behaviour for both the peak and post-peak regions. The laboratory tests were conducted with a servo-controlled testing machine to obtain complete stress–strain curves. The test results include unconfined and triaxial compressive strengths, shear strengths an...

A homogenization strategy for granular materials is presented and applied to a three-dimensional Discrete Element Method (DEM), that uses superellipsoids as particles. Macroscopic quantities are derived from the microscopic quantities resulting from a DEM simulation by averaging over representative volume elements (RVEs). The implementation of a RVE is described in detail regarding the definiti...

Considering the relationship between inhomogeneous plastic deformation and fatigue damage, inhomogeneity evolution failure of superalloy GH4169 under temperature 500 °C macro tension compression cyclic loading are studied, by using crystal plasticity calculation associated with polycrystalline representative Voronoi volume element (RVE). Different statistical standard deviation differential ent...

Single-crystal magnesium micropillars (5 µm diameter) have been fabricated using focused ion beam (FIB) milling and loaded in compression along the [21¯1¯0] direction at cryogenic temperature (T = 184 K) three different strain rates: 10-4, 5 × 10-3 10-1 s-1. The stress-strain curves post-mortem analyses reveal predominance of {101¯2} twinning. critical stress required for twinning is detected t...