In order to evaluate the reliability of cracked cylindrical shell effectively and reasonably, study load capacity structures understand failure modes structures, in this paper finite element method is adopted for shells with mixed mode crack. The models an inclined through crack under external pressure were established by method, elastic elastic-plastic buckling loads calculated. influences len...

The strength deterioration and fracture tendency of freeze-thaw rock determine the construction operation safety engineering. This article conducted compression-shear composite load tests on sandstones with various saturations to examine failure law rocks in cold climates contributing elements degradation. It was found that an increase saturation loading angle, compressive elastic modulus dropp...

Small-scale cohesive-zone models based on potential functions are expected to be consistent with the important features of linear-elastic fracture mechanics (LEFM). These include an inverse-square-root K-field ahead a crack, normal and shear stresses being proportional mode-I mode-II stress-intensity factors, KI KII, work done against crack-tip tractions equal KI2+KII2?E?, where E? is appropria...

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...

Since rocks are aggregates of mineral particles, the effect of mineral microstructure on macroscopic mechanical behaviors of rocks is inneglectable. Rock samples of four different particle shapes are established in this study based on clumped particle model, and a sphericity index is used to quantify particle shape. Model parameters for simulation in PFC are obtained by triaxial compression tes...

Atomic Force Microscope images of a crack intersecting the free surface of a glass specimen are taken at different stages of subcritical propagation. From the analysis of image pairs, it is shown that a novel Integrated Digital Image Correlation technique allows to measure stress intensity factors in a quantitative fashion. Image sizes as small as 200 nm can be exploited and the surface displac...

To investigate the effect of crack angle on fracture performance brittle materials under tensile load, a molecular dynamics simulation method based ReaxFF is used to establish an amorphous silica model through high-temperature melting and annealing process. Under environment 300 K, 1.013 × 105 Pa 5 109 s−1, impact from three perspectives analyzed: material mechanical properties, micro process, ...

Almost all of the research on cracks in laser cladding is based, at present, a horizontal substrate, which cannot be directly applied to prepare high performance coatings, especially hardness tilted substrate. In this work, influence substrate’s tilt angle crack behavior Ni60A coating studied, based intensity distribution and energy attenuation models Results show that cracking rate (the number...

In this work, the plastic deformation mechanisms responsible for mechanical properties and fracture toughness in nanotwinned (NT) magnesium is studied by molecular dynamics (MD) simulation. The influence of twin boundary (TBs) spacing and crack position on deformation behaviors are investigated. The microstructure evolution at the crack tip are not exactly the same for the left edge crack (LEC)...

Ultrasonic techniques have the potential to provide early detection of fatigue induced cracks originating from fastener holes with the long term goal of structural health monitoring. This paper considers energy-based algorithms for analyzing ultrasonic waveforms obtained using fixed angle beam transducers in a through-transmission configuration. The transducers were located on either side of th...