The dynamic fracture behavior of layered architectures is experimentally studied. Specifically, crack penetration, trapping, and branching at an interface are examined. A newly introduced optical technique called Digital Gradient Sensing (DGS) that quantifies elasto-optic effects due to a non-uniform state of stress is extended to perform full-field measurements during the fracture event using ...

Concrete is a so called quasibrittle material which, despite predominantly elastic material response, exhibits in tension loading a stable non-linear fracture response, when tested under displacement control. The reason for the non-linearity is the development of a fracture process zone, in front of the crack, due to micro-cracking and crack bridging. The effect of the fracture process zone is ...

Bone fracture is a health concern for those with aged bone and brittle bone diseases. Mouse bone is widely used as a model of human bone, especially to investigate preclinical treatment strategies. However, little is known about the mechanisms of mouse bone fracture and its similarities and differences from fracture in human bone. In this work we present a methodology to investigate the fractur...

BACKGROUND There are no evidence on the effects of low-intensity pulsed ultrasound (LIPUS) on surgically managed fresh fractures. We therefore performed a multicenter retrospective cohort study to investigate the effects of LIPUS on surgically managed fresh fractures. METHODS This study included patients surgically treated for diaphyseal fractures of the femur or tibia between August 2009 and...

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...

The finite element alternating method is an attractive and efficient method for calculating the stress intensity factor of cracks emanating from fastener holes such as the problem of multiple site damage (MSD) at the fuselage skin of aging aircraft. While the alternating method has been used to solve various engineering problems in assessing the structural integrity of aging aircraft, this meth...

This paper is the third part of a study dealing with the mechanical and fracture mechanical characterization of Medium Density Fiberboards (MDF). In the first part, an analysis of internal bond strength testing was performed and in the second part MDF was analyzed by means of the wedge splitting experiment; this part deals with the double cantilever I beam test, which is designed for measuring ...

Brittle materials such as rock and ceramic usually exhibit apparent increases of strength and toughness when subjected to dynamic loading. The reasons for this phenomenon are not yet well understood, although a number of hypotheses have been proposed. Based on dynamic fracture mechanics, the present work offers an alternate insight into the dynamic behaviors of brittle materials. Firstly, a sin...

A generalized method for characterizing mechanical stresses in brittle materials during crack tip propagation is presented. This approach was derived from classical fracture mechanics and is therefore mechanism independent and applies to any isotropic brittle material, including glasses, fine grained ceramics or metals, and high stiffness polymers. A practical implementation demonstrates the me...