The present paper adopts a Bayesian approach to update some of the parameters of the probability distributions governing the reliability assessment of maintained floating structures. It is based on a time dependent fatigue reliability formulation presented earlier but the description of the time to crack initiation, crack growth law and probability of crack detection are updated using the infor...

This paper presents experimental results from the vibration of a polycarbonate beam containing a crack that opens and closes dudng vibration. Several techniques were employed to detect and locate the crack making use of the nonlinearity. “Harmonic mode shapes” proved to be more sensitive to damage than conventional mode shapes. Instantaneous f requency and timefrequency methods also showed clea...

The breakage of capsules upon crack propagation is crucial for achieving crack healing in encapsulation-based self-healing materials. A mesomechanical model was developed in this study to simulate the process of crack propagation in a matrix and the potential of debonding. The model used the extended finite element method (XFEM) combined with a cohesive zone model (CZM) in a two-dimensional (2D...

Effects of dislocation emission from a mode I crack and of pinning distances on the behavior of the crack and on fracture toughness in aluminum were studied by using the Molecular Statics Technique with atomic interactions described in terms of the Embedded Atom Method. It was found that aluminum is a ductile material in which the cracks generate dislocations, blunting the cracks. The blunting ...

This research was initiated to investigate the capability of using lasers for crack detection in pavements. If such a capability could be developed it would be used to aid in obtaining and evaluating pavement distress and cracking information for the State's P.E.S. procedures, used for maintaining and evaluating pavements. The research effort has involved three stages. The first two stages were...

Abstract. Eddy current testing using a pickup coil is usually applied to the surface detection of cracks because of its high frequency. However, for metal infrastructure, detection of not only the surface but also internal cracks is desired. Therefore, we have developed a low-frequency eddy current testing system to inspect interior structures using a magneto-resistive (MR) sensor with a wide m...

Automated systems for road crack detection are extremely important in road maintenance for vehicle safety and traveler’s comfort. Emerging cracks in roads need to be detected and accordingly repaired as early as possible to avoid further damage thus reducing rehabilitation cost. In this paper, a robust method for Gabor filter parameters optimization for automatic road crack detection is discuss...

One of the useful applications of wireless sensor networks is structural health monitoring, where sensors are distributed to monitor buildings, bridges, large dams, and etc. Out of a large number of application domains we focus on the fatigue crack detection of a structure, e.g., bridge. In this chapter, we summarize the required components for data networking in autonomous fatigue crack detect...

Fracture propagation, especially for fractures emanating from inclined wellbores and closed natural fracture often involves Mode I, Mode II and at times Mode III fracture pattern. When an embedded inclined 3D fracture is subjected to compression, the fracture tips are restrained by the surrounding materials so that it does not propagates as predicted by 2D fracture models. In this paper, threed...