Shear-wave splitting, observed in microearthquake records at The NW and SE Geysers geothermal fields, CA has proved to be effective in the detection of subsurface crack orientations and crack densities. Crust anisotropy due to patterns of stress-aligned fractures causes approaching shear-waves to split into fast and slow arrivals. Within the shear-wave window of a given seismic station, the mea...

Self-healing alloys are promising materials that can decrease the consequences of accidents. To detect crack formation in a material is simple task that can be performed by e.g., sonic or ultrasound detection, but it is not always possible to immediately replace the damaged parts. In this situation, it is very advantageous to have the chance to heal the crack during operation, which can be done...

The use of microwave technique has proved to be a viable means for crack detection and sizing surface cracks in metals. In this technique, the surface of the specimen is interrogated with a radiating open-ended waveguide probe and a crack is assumed to be a simple short-circuited rectangular waveguide, causing peturbations in the probe reflection coefficient. Since the growth of fatigue in meta...

A large area electronics in the form of a soft elastomeric capacitor (SEC) has shown great promise as a strain sensor for fatigue crack monitoring in steel structures. The SEC sensors are inexpensive, easy to fabricate, highly stretchable, and mechanically robust. It is a highly scalable technology, capable of monitoring deformations on mesoscale systems. Preliminary experiments verified the SE...

Worldwide consumption in oil and natural gas is expected to lead all other energy sources in the next 20 years. The oil & gas pipeline network will constantly expand placing greater demand on operators to ensure any integrity threats to these pipeline systems are accurately and reliably identified. What are the main integrity threats to pipelines? There are many such as third-party damage, exte...

Conventional distress detection method which dealing with each image through single algorithm and under single scale with lower efficiency. A robust and high-efficiency model for segmentation and distress statistic of massive pavement images which based on multi-scale space is proposed in this paper. It based on the facts that: (1) the crack pixels in pavement images are darker than their surro...

This paper presents the experimental results regarding acoustic emission signals measured during the injection molding of those standard test specimens commonly used for examining the shrinkage behaviour of various thermoplastic materials. In daily industrial production of different plastic products we often have to deal with various errors that practically occur on the mold primarily as a resu...

Pavement cracks are important information for evaluating the road condition and conducting the necessary road maintenance. In this paper, we develop CrackTree, a fully-automatic method to detect cracks from pavement images. In practice, crack detection is a very challenging problem because of (1) low contrast between cracks and the surrounding pavement, (2) intensity inhomogeneity along the cra...

Cracks on a bridge deck should be ideally detected at an early stage in order to prevent further damage. To ensure safety, it is necessary to inspect the quality of concrete decks at regular intervals. Conventional methods usually include manual inspection of concrete surfaces to determine defects. Though very e↵ective, these methods are time-ine cient. This paper presents the use of computer-v...

One of the major issues from a structural integrity point of view of the aircraft structure is an appropriate health monitoring technology delivery for the damage tolerant philosophy. This paper presents a development of a system for fatigue crack growth monitoring and early damage detection in the PZL – 130 ORLIK TC II turbo-prop military trainer aft structure. The maintenance system of the ai...