We introduce models for static and quasi-static damage in elastic materials, based on a strain threshold, and then investigate the relationship between these threshold models and the energy-based models introduced in [17] and [15]. A somewhat surprising result is that, while classical solutions for the energy models are also threshold solutions, this is not the case for nonclassical solutions, ...

This paper investigates the effect of crystallographic orientation on the mode of material removal (ductile vs. brittle) in diamond scribing of single crystal silicon (c-Si) and offers an explanation for the observed effects in terms of the combined role of phase transformation and slip generation. Single-point diamond scribing tests are performed on (111), (001) and (110) crystallographic plan...

In this study a polypropylene material with talcum reinforcement used for sewer pipes has been subjected to an annealing procedure at 80°C, roughly 60°C above the actual application temperature, in air for a time period of 18 months. As expected, examination of the material showed no significant decrease in mechanical or fracture mechanical properties due to the temperature exposure. However, s...

A new brittle-elastoviscoplastic (BEVP) fluid model is presented in this paper. This relatively simple to use, as it contains few material parameters and a fixed-point algorithm effective for solving the coupled system of equations. The combines some existing fundamental features such elasticity, plasticity brittle damage. combination them based on thermodynamics that ensures positivity dissipa...

As a cementitious material, geopolymers show a high quasi-brittle behavior and a relatively low fracture energy. To overcome such a weakness, incorporation of fibers to a brittle matrix is a well-known technique to enhance the flexural properties. This study comprehensively evaluates the short and long term impacts of different volume percentages of polypropylene fiber (PPF) reinforcement on fl...

Cracking of rocks and rock-like materials exhibits a rich variety patterns where tensile (mode I) shear II) fractures are often interwoven. These mixed-mode usually cohesive (quasi-brittle) frictional. Although phase-field modeling is increasingly used for rock fracture simulation, no formulation available frictional fracture. To address this shortfall, here we develop double-phase-field that e...

Discrete fine-scale models, in the form of either particle or lattice models, have been formulated successfully to simulate the behavior of quasi-brittle materials whose mechanical behavior is inherently connected to fracture processes occurring in the internal heterogeneous structure. These models tend to be intensive from the computational point of view as they adopt an “a priori” discretizat...

The failure of brittle and quasi-brittle polymers can be attributed to a multitude of random microscopic damage modes, such as fibril breakage, crazing, and microfracture. As the load increases, new damage modes appear, and existing ones can transition into others. In the example polymer used in this study--a commercially available acrylic bone cement--these modes, as revealed by scanning elect...