This article discusses results obtained from a parametric study to analytically evaluate the impingement of a crack at the interface of an environmental barrier coating (EBC) and a monolithic Silicon nitride (Si 3 N 4) layered ceramics substrate. The study establishes a correlation that leads to determine if the crack is arrested or advanced by either penetrating or deflecting along the EBC/sub...

Assuming that a material point becomes unstable when the e€ective plastic strain there reaches a critical value, it is found that a material instability will initiate at a point on the crack-tip of an impulsively loaded prenotched plate that makes an angle of )14° to the notch-tip. This agrees well with the observed values of )5° to )15°. Ó 1998 Elsevier Science Ltd. All rights reserved.

In this work, the effect of rock bolt angle on the shear behavior of Rock Bridges is investigated using the particle flow code in two dimensions (PFC2D) for three different Rock Bridge lengths. Firstly, the calibration of PF2D is performed to reproduce the gypsum sample. Then the numerical models with the dimensions of 100 mm * 100 mm are prepared. The Rock Bridge is created in the middle of th...

The mechanical behavior of multicracks under compression has become a very important project in the field of fracture mechanics and rock mechanics. In this paper, experimental and numerical studies on the fracture property of three collinear cracks under compression were implemented. The specimens were a square concrete plate, and the cracks were made by a very thin film. The tests were conduct...

Abstract As a commonly used and effective technology for increasing the permeability of coal–rock reservoirs, hydraulic fracturing has been widely in engineering sites to realize efficient exploitation utilization gas resources reservoirs. The core is initiation, propagation, path cracks. In this paper, combination true triaxial physical test numerical simulation study influence coal bedding ch...

Potential sensitivity of the buckling behavior of cracked composite cylindrical shells to service life cracking is explored by carrying out linear buckling analysis. Computational models of cracked composite cylindrical shells are developed by exploiting a special meshing scheme in which the element size is reduced incrementally from the element size employed in the uncracked region by approach...

This paper presents a new model, called the "shear-friction truss model," for slender reinforced concrete beams to derive a clear and simple design equation for their ultimate shear strength. In this model, a portion of the shear strength is provided by shear reinforcement as in the traditional truss model, and the remainder by the shear-friction mechanism. Friction resistance is derived consid...

Silicon nitride ceramic bearings are widely used for their excellent performance. However, due to special manufacturing method, cracks will occur on ball surface, and this initial surface crack propagate under the action of cyclic stress, which lead material spalling. This greatly limit its service life in practical applications, especially heavy load at high speed. Therefore, it is necessary s...

In a previous experimental study, it was observed that the break-through process of a cleavage front across a high-angle grain boundary can be highly nonuniform. While the central part of the boundary can be cleaved quite smoothly, the rest parts must be sheared apart. In this paper, the trapping effect of grain boundary shearing is analyzed in considerable detail. Before the shearing is comple...