The classical truss model (or strut-and-tie model) for shear failure of reinforced concrete beams is modified to describe fracture phenomena during failure. The failure is assumed to be caused by propagation of a compression fracture across the concrete strut during the portion of the loading history in which the maximum load is reached. The compression fracture may consist of a band of splitti...

Numerical simulation is very useful for understanding the hydraulic fracturing mechanism. In this paper, we simulate the hydraulic fracturing using the distinct element approach, to investigate the effect of some critical parameters on hydraulic fracturing characteristics. The breakdown pressure obtained by the distinct element approach is consistent with the analytical solution. This indicates...

In this paper, configurations of pre-existing fractures in cubic rock blocks were investigated and reconstructed for the modeling of experimental hydraulic fracturing. The fluid-rock coupling process of hydraulic fracturing was simulated based on the displacement discontinuities method. The numerical model was validated against the related laboratory experiments. The stimulated fracture configu...

Several DXA-based structural engineering models (SEMs) of the proximal femur have been developed to estimate stress caused by sideway falls. Their usefulness in discriminating hip fracture has not yet been established and we therefore evaluated these models. The hip DXA scans of 51 postmenopausal women with hip fracture (30 femoral neck, 17 trochanteric, and 4 unspecified) and 153 age-, height-...

Fractured-rock aquifers display spatially and temporally variable hydraulic conductivity generally attributed to variable fracture intensity and connectivity. Empirical evidence suggests fracture aperture and hydraulic conductivity are sensitive to in situ stress. This study investigates the sensitivity of fractured-rock hydraulic conductivity, groundwater flow paths, and advectiondominated tra...

Stress-intensity factors (SIFs) are the most important parameters in fracture mechanics analysis of structures. These parameters are evaluated for a stationary crack in functionally graded plates of arbitrary geometry using a novel Galerkin based mesh-free method. The method involves an element-free Galerkin method (EFGM), where the material properties are smooth functions of spatial coordinate...

Addition of titanium (Ti) to ASTM A710 Grade B Cu-precipitation-strengthened steel significantly increases the impact absorbed fracture energy and reduces the ductile-to-brittle transition temperature. The effect of Ti correlates with the reduction of the amount of pearlite in the ferritic microstructure. A thorough study of the mechanical properties of Ti-modified A 710B steel is presented. In...

We study atomistically the fracture of single-crystal silicon at atomically sharp notches with opening angles of 0° ~a crack!, 70.53°, 90° and 125.3°. Such notches occur in silicon that has been formed by etching into microelectromechanical structures and tend to be the initiation sites for failure by fracture of these structures. Analogous to the stress intensity factor of traditional linear e...

Fracture behavior of Zr55Cu30Al10Ni5 bulk metallic glass was investigated under quasi-static compression at strain rate of 10/s using an Instron testing machine and dynamic split Hopkinson bar (SHPB) compression with strain rate of about 1900–4300/s. Pronounced strain softening, especially past the peak stress, was observed under SHPB tests and compared with the distinct flow serrations under q...

Article history: Received: 21.04.2014. Received in revised form: 02.07.2014. Accepted: 14.07.2014. Due to the high amount of carbon and diffusible hydrogen, high-strength wear-resistant steel NM360, which is widely used on excavating machinery, always tends to develop cold crack after welding. Heat affected zone (HAZ) is the weakest part in a welding joint and is the most probable location for ...