the cracked brazilian disc (cbd) specimen is widely used in order to determine mode-i/ii and mixed-mode fracture toughness of a rock medium. in this study, the stress intensity factor (sif) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (x-fem). this method is based upon the finite element method (fem). in this m...

Cracked and un-cracked Brazilian disc specimens subjected to diametral compression were used for conducting fracture toughness and tensile strength experiments on a polymer concrete (PC) material. The value of mode I fracture toughness (KIc) was determined from the center- cracked Brazilian disc and the indirect tensile strength (σt) was obtained from the un-cracked Brazilian disc specimen. The...

cracked and un-cracked brazilian disc specimens subjected to diametral compression were used for conducting fracture toughness and tensile strength experiments on a polymer concrete (pc) material. the value of mode i fracture toughness (kic) was determined from the center- cracked brazilian disc and the indirect tensile strength (σt) was obtained from the un-cracked brazilian disc specimen. the...

considering the fact that rocks fail faster under tensile stress, rock tensile strength is of greatimportance in applications such as blasting, rock fragmentation, slope stability, hydraulic fracturing,caprock integrity, and geothermal energy extraction. there are two direct and indirect methods tomeasure tensile strength. since direct methods always encompass difficulties in test setup, indire...

Considering the fact that rocks fail faster under tensile stress, rock tensile strength is of greatimportance in applications such as blasting, rock fragmentation, slope stability, hydraulic fracturing,caprock integrity, and geothermal energy extraction. There are two direct and indirect methods tomeasure tensile strength. Since direct methods always encompass difficulties in test setup, indire...

The cracked Brazilian disc (CBD) specimen is widely used in order to determine mode-I/II and mixed-mode fracture toughness of a rock medium. In this study, the stress intensity factor (SIF) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (X-FEM). This method is based upon the finite element method (FEM). In this m...

An assessment is made here of the role played by the micropolar continuum theory on the cracked Brazilian disc test used for determining rock fracture toughness. By analytically solving the corresponding mixed boundary-value problems and employing singular-perturbation arguments, we provide closed-form expressions for the energy release rate and the corresponding stress-intensity factors for bo...

Abstract In this study, mode I fracture tests on cracked straight-through Brazilian disc (CSTBD) and notched semi-circular bend (NSCB) shale specimens with different sizes were conducted to investigate the difference between maximum tangential stress criterion size effect law (SEL) model in predicting apparent toughness ( K a ) of shale. addition, effects specimen geometry selection prediction ...

The unsustainable use of resources and the rising demand for traditional concrete have disrupted ecological equilibrium, necessitating adoption a more appropriate long-lasting alternative. One such substitute cement in production is geopolymer concrete, although this material prone to cracking fracturing due its low tensile strength, leading costly repairs or even structural collapse. Fiber-rei...