This paper studies the application of an inverse methodology for problem solving in fracture mechanics using the finite element analysis. The method was applied to both detection of subsurface cracks and the study of propagating cracks. The procedure for detection of subsurface cracks uses a first order optimization analysis coupled with a penalty function to solve for the unknown geometric par...

By partitioning the total stresses in a damaged composite into either mechanical and residual stresses or into initial and perturbation stresses, it was possible to derive two exact results for the energy release rate due to crack growth. These general results automatically include the effects of residual stresses, tractionloaded cracks, and imperfect interfaces. These effects are normally not ...

A concept of "Fractal Fracture Mechanics" for HDR .(Hot Dry Rock) geothermal reservoir design has been developed as an extension of conventional rock fracture mechanics. It is suggested that this concept is successfully applicable to characterize and model subsurface fracture network in HDR geothermal reservoir. Furthermore, this modeling procedure makes it possible to evaluate the thermal ener...

Interfaces between two different mixes or strengths of concrete appear in large concrete structures involving mass concreting such as dams, nuclear containment vessels, cooling towers etc., since joints between successive lifts are inevitable. These joints and interfaces are potential sites for crack formation, leading to weakening of mechanical strength and subsequent failure. Research involvi...

The mixed brittle–plastic fiber bundle model is an extension model based on the classical fiber bundlemodel to describe the nonbrittle failure process of some hierarchical structure materials such as spider silk. In order to explore the breaking dynamic properties of the hierarchical structure materials in short-range correlation, the mixed brittle–plastic fiber bundle model in local load shari...

Indentation techniques for assessing fracture toughness are attractive due to the simplicity and expediency of experiments, and because they potentially allow the characterization of both local and bulk fracture properties. Unfortunately, rarely have such techniques been proven to give accurate fracture toughness values. This is a concern, as such techniques are seeing increasing usage in the s...

2. Vehicles can be designed to provide crash protection to the occu little or no penalty to the weight and cost of the vehicle. 3. Vehicle crashworthiness can be improved by providing the principles to designers and by emphasizing the importance of this design responsibility. Decisions and design choices can then be · and in cases where two or more comparable choices are possible, the in favor ...

The classical, overall objective of fracture mechanics is the determination of the rate of change of the shape of an existing crack. Will it propagate under given loading and environmental conditions, and, if it does propagate, at what rate and into what configuration will it do so? The corresponding computational requirement has been to obtain the fields – displacement, strain, stress, and ene...

The so-called Complexity Sciences are a topic of fast growing interest inside the scientific community. Actually, researchers did not come to a definition of complexity, since it manifests itself in so many different ways [1]. This field itself is not a single discipline, but rather a heterogeneous amalgam of different techniques of mathematics and science. In fact, under the label of Complexit...