scholarly journals The Potential of Optical Profilometry in the Study of Cultural Stone Weathering

2019 ◽  
Vol 5 (6) ◽  
pp. 60
Author(s):  
Dario Ambrosini ◽  
Tullio de Rubeis ◽  
Iole Nardi ◽  
Domenica Paoletti
Keyword(s):  
Surface Shape ◽  
Optical Profilometry ◽  
Stone Monuments ◽  
Advantages And Disadvantages ◽  
Scientific Terms ◽  
Stone Weathering ◽  
Contact Survey ◽  
Non Destructive ◽  
Degree Of Degradation ◽  
Non Destructive Techniques

The problem of deterioration of marble or stone monuments on display in the open air was raised in scientific terms around the mid-nineteenth century, correctly sensing the close dependence between the increased speed of surfaces alteration and air pollution. However, only more recently, around the years 1980–1990, emerged a need for quantitative data to assess the degree of degradation and the relative danger in the future projections. Non-destructive techniques can be an important aid in assessing the state of degradation and, above all, its speed, directly on the most important monuments exposed to the urban environment. In this work we discuss some non-destructive techniques able to evaluate the alteration of the surface shape of artefacts exposed to the environment through a non-contact survey of their surface shape. Advantages and disadvantages will be highlighted, as well as the problems still open.

scholarly journals Inductive Thermography as Non-Destructive Testing for Railway Rails

2021 ◽  
Vol 11 (3) ◽  
pp. 1003
Author(s):  
Christoph Tuschl ◽  
Beate Oswald-Tranta ◽  
Sven Eck
Keyword(s):  
Eddy Current ◽  
Electrical Discharge Machining ◽  
Rolling Contact ◽  
Heat Diffusion ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Ir Camera ◽  
Advantages And Disadvantages ◽  
Average Crack ◽  
Non Destructive

Inductive thermography is a non-destructive testing method, whereby the specimen is slightly heated with a short heating pulse (0.1–1 s) and the temperature change on the surface is recorded with an infrared (IR) camera. Eddy current is induced by means of high frequency (HF) magnetic field in the surface ‘skin’ of the specimen. Since surface cracks disturb the eddy current distribution and the heat diffusion, they become visible in the IR images. Head checks and squats are specific types of damage in railway rails related to rolling contact fatigue (RCF). Inductive thermography can be excellently used to detect head checks and squats on rails, and the method is also applicable for characterizing individual cracks as well as crack networks. Several rail pieces with head checks, with artificial electrical discharge-machining (EDM)-cuts and with a squat defect were inspected using inductive thermography. Aiming towards rail inspection of the track, 1 m long rail pieces were inspected in two different ways: first via a ‘stop-and-go’ technique, through which their subsequent images are merged together into a panorama image, and secondly via scanning during a continuous movement of the rail. The advantages and disadvantages of both methods are compared and analyzed. Special image processing tools were developed to automatically fully characterize the rail defects (average crack angle, distance between cracks and average crack length) in the recorded IR images. Additionally, finite element simulations were used to investigate the effect of the measurement setup and of the crack parameters, in order to optimize the experiments.

How to combine several non-destructive techniques for a better assessment of concrete structures

2008 ◽  
Vol 38 (6) ◽  
pp. 783-793 ◽  
Author(s):  
D. Breysse ◽  
G. Klysz ◽  
X. Dérobert ◽  
C. Sirieix ◽  
J.F. Lataste
Keyword(s):  
Concrete Structures ◽  
Non Destructive ◽  
Non Destructive Techniques

First-time observation of Mastro Giorgio masterpieces by means of non-destructive techniques

2006 ◽  
Vol 83 (4) ◽  
pp. 475-483 ◽  
Author(s):  
G. Padeletti ◽  
G.M. Ingo ◽  
A. Bouquillon ◽  
S. Pages-Camagna ◽  
M. Aucouturier ◽  
...  
Keyword(s):  
Time Observation ◽  
First Time ◽  
Non Destructive ◽  
Non Destructive Techniques

scholarly journals Investigation of new volumetric non-destructive techniques to characterise additive manufacturing parts

2018 ◽  
Vol 62 (5) ◽  
pp. 1049-1057 ◽  
Author(s):  
A-F. Obaton ◽  
M-Q. Lê ◽  
V. Prezza ◽  
D. Marlot ◽  
P. Delvart ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Non Destructive ◽  
Non Destructive Techniques

Experiences in Examining and Dispositioning Flaws in Zr-2.5Nb Pressure Retaining CANDU Reactor Components

2002 ◽  
Author(s):  
Andrew Celovsky ◽  
John Slade
Keyword(s):  
Service Life ◽  
Reactor Core ◽  
Pressure Tube ◽  
Candu Reactors ◽  
Periodic Inspection ◽  
Pressure Tubes ◽  
Surveillance Programs ◽  
Non Destructive ◽  
Limited Service ◽  
Non Destructive Techniques

CANDU reactors use Zr-2.5 Nb alloy pressure tubes, as the primary pressure boundary within the reactor core. These components are subject to periodic inspection and material surveillance programs. Occasionally, the inspection program uncovers a flaw, whereupon the flaw is assessed as to whether it compromises the integrity of the pressure-retaining component. In 1998, such a flaw was observed in one pressure tube of a reactor. Non-destructive techniques and analysis were used to form a basis to disposition the flaw, and the component was fit for a limited service life. This component was eventually removed from service, whereupon the destructive examinations were used to validate the disposition assumptions used. Such a process of validation provides credibility to the disposition process. This paper reviews the original flaw and its subsequent destructive evaluation.

Study on the Measuring Instruments and Strength Size Effect of the Surface Shape of Rigid Structure Plane

2011 ◽  
Vol 250-253 ◽  
pp. 2327-2332
Author(s):  
Feng Ji ◽  
Yu Chuan Shi
Keyword(s):  
Size Effect ◽  
Precise Measurement ◽  
Rock Sample ◽  
Surface Shape ◽  
Measuring Instruments ◽  
Rigid Structure ◽  
Advantages And Disadvantages ◽  
Structure Surface ◽  
Structure Plane ◽  
Working Efficiency

The surface shape of structure plane is closely related with its mechanics property. Precise measurement to the surface shape of structure plane is the basis of deformation mechanism and strength characteristics. On the basis of studying advantages and disadvantages of the measuring instrument, the author has developed a new kind of portable measuring instruments innovatively - Contact Punching Device which has improved open-air working efficiency greatly. Application results show that JRC obtained by the Contact Punching Device is very close to the actual JRC of surface shape of the structure plane. Then about size effect of rigid structure plane, got the following principle that the statistical variance of the undulating roughness of the structure surface decays gradually with length of the rock sample, and got the limiting length of the undulating roughness when the influence of shearing intensity of the structure is dispelled. Finally, which proved through the embodiment of different rock and different weathering rock, the result indicates this method can be applied to engineering.

Assessment of a Medieval Arch Bridge Resorting to Non-destructive Techniques and Numerical Tools

2019 ◽  
pp. 464-472
Author(s):  
Daniel V. Oliveira ◽  
Reza Allahvirdizadeh ◽  
Ana Sánchez ◽  
Belen Riveiro ◽  
Nuno Mendes ◽  
...  
Keyword(s):  
Arch Bridge ◽  
Numerical Tools ◽  
Non Destructive ◽  
Non Destructive Techniques

Non-destructive techniques of detecting plant diseases: A review

2019 ◽  
Vol 108 ◽  
pp. 101426 ◽  
Author(s):  
Maimunah Mohd Ali ◽  
Nur Azizah Bachik ◽  
Nur ‘Atirah Muhadi ◽  
Tuan Norizan Tuan Yusof ◽  
Chandima Gomes
Keyword(s):  
Plant Diseases ◽  
Non Destructive ◽  
Non Destructive Techniques
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