It is vital for the study of fracturing parameters optimal design and fluids rate forecast to calculate fracture propagation parameters accurately. In order to calculate fracture propagation accurately, in this paper, the model for calculating the value of energy release when the rock body collapses was established basing on catastrophe theory, considering that the collapse of fracturing rock b...

Buckling-driven delamination is considered among the most critical failure modes in composite laminates. This paper examines the propagation of delaminations in a beam under pure bending. A pre-developed analytical model to predict the critical buckling moment of a thin sub-laminate is extended to account for propagation prediction, using mixed-mode fracture analysis. Fractography analysis is p...

This study outlines a new method for disposing of hazardous (e.g., nuclear) waste. The technique is called Abyssal Sequestration, and it involves placing the waste at extreme depths in Earth’s crust where it could achieve the geologically long period of isolation. Abyssal Sequestration involves storing the waste in hydraulic fractures driven by gravity, a process we term as gravity fracturing. ...

OBJECTIVES To observe porcelain veneer behavior of zirconia and metal-ceramic full coverage crowns when subjected to compression testing, comparing zirconia cores to metal cores. STUDY DESIGN The porcelain fracture surfaces of 120 full coverage crowns (60 with a metal core and 60 with a zirconia core) subjected to static load (compression) testing were analyzed. Image analysis was performed u...

OBJECTIVES To quantify incremental effects of applying different criteria to identify men who are candidates for drug treatment to prevent fracture and to examine the extent to which fracture probabilities vary across distinct categories of men defined by these criteria. DESIGN Cross sectional and longitudinal analysis of a prospective cohort study. SETTING Multicenter Osteoporotic Fracture...

The structural reliability of many brittle materials such as structural ceramics relies on the occurrence of intergranular, as opposed to transgranular, fracture in order to induce toughening by grain bridging. For a constant grain boundary strength and grain boundary toughness, the current work examines the role of grain strength, grain toughness, and grain angle in promoting intergranular fra...

This paper investigates the roles of external loads and specimen geometry on crack path selection in adhesively bonded joints. First, the effect of mixed mode fracture on crack path selection is studied. Using epoxy as an adhesive and aluminum as the adherends, double cantilever beam (DCB) specimens with various T-stress levels are prepared and tested under mixed mode fracture loading. Post-fai...

Dynamics of amorphization and fracture in SiSe 2 nanowires are studied using the molecular-dynamics method. We find that fracture is initiated in an amorphous region at the nanowire surface. Local amorphization propagates across the nanowire while multiple cracks start at the boundaries of the amorphous region. Results for the time evolution of amorphization, crack propagation, and fracture are...

OBJECTIVE To evaluate the effectiveness of the method of radiographic interpretation of acetabular fractures, according to the classification of Judet and Letournel, used by a group of residents of Orthopedics at a university hospital. METHODS We selected ten orthopedic residents, who were divided into two groups; one group received training in a methodology for the classification of acetabul...