Non-destructive mechanical and physical in-situ testing of rendered walls under natural exposure

2020 ◽  
Vol 230 ◽  
pp. 116838 ◽  
Author(s):  
J. Galvão ◽  
R. Duarte ◽  
I. Flores-Colen ◽  
J. de Brito ◽  
A. Hawreen
Keyword(s):  
In Situ Testing ◽  
Natural Exposure ◽  
Non Destructive

Influence of Water Content on Fundamental Frequency of Mortar Sample

2015 ◽  
Vol 1124 ◽  
pp. 273-279 ◽  
Author(s):  
Ladislav Carbol ◽  
Jan Martinek ◽  
Ivo Kusák
Keyword(s):  
Water Content ◽  
Fundamental Frequency ◽  
Non Destructive Testing ◽  
In Situ Testing ◽  
Mortar Sample ◽  
Destructive Testing ◽  
Impact Echo ◽  
Influence Of Water ◽  
Non Destructive

Ultrasonic non-destructive testing methods such as Impact-echo are often conducted under different conditions. Such results might be distorted by ambient temperature or by water content of the tested sample. Tested mortar sample displayed shift of the fundamental frequency by 3.7 %. This article confirms necessity of standardized conditions during ultrasonic testing for both laboratory and in-situ testing.

scholarly journals Methodology for the in situ testing of the moisture content of brick walls: an example of application

2020 ◽  
Vol 20 (4) ◽  
Author(s):  
Anna Hoła
Keyword(s):  
Moisture Content ◽  
Fourteenth Century ◽  
In Situ Testing ◽  
Negative Effects ◽  
Non Destructive ◽  
Historical Periods ◽  
Destructive Methods ◽  
Author Knowledge

Abstract The article presents original methodology of testing the moisture content of brick walls in buildings. It was developed on the basis of own experience acquired during testing the moisture content in many excessively wet buildings erected in various historical periods. The tests were conducted using different methods, including non-destructive methods. To emphasize the importance of the problem, an overview of the methodology was preceded by a brief presentation of the causes and negative effects of excessive moisture and salinity in brick walls. In addition, the article is illustrated with an example of the effects of moisture content tests carried out according to the developed methodology on a facility from the fourteenth century. According to the author, knowledge of the presented methodology, and its application, should contribute to both the improvement of the quality of conducted research and the credibility of the obtained results.

scholarly journals Laser-excited elastic guided waves reveal the complex mechanics of nanoporous silicon

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Marc Thelen ◽  
Nicolas Bochud ◽  
Manuel Brinker ◽  
Claire Prada ◽  
Patrick Huber
Keyword(s):  
Guided Waves ◽  
Laser Ultrasonics ◽  
Bulk Silicon ◽  
Nanoporous Silicon ◽  
Stiffness Reduction ◽  
Mechanical Characterisation ◽  
Isotropic Elasticity ◽  
On Chip ◽  
Non Destructive

AbstractNanoporosity in silicon leads to completely new functionalities of this mainstream semiconductor. A difficult to assess mechanics has however significantly limited its application in fields ranging from nanofluidics and biosensorics to drug delivery, energy storage and photonics. Here, we present a study on laser-excited elastic guided waves detected contactless and non-destructively in dry and liquid-infused single-crystalline porous silicon. These experiments reveal that the self-organised formation of 100 billions of parallel nanopores per square centimetre cross section results in a nearly isotropic elasticity perpendicular to the pore axes and an 80% effective stiffness reduction, altogether leading to significant deviations from the cubic anisotropy observed in bulk silicon. Our thorough assessment of the wafer-scale mechanics of nanoporous silicon provides the base for predictive applications in robust on-chip devices and evidences that recent breakthroughs in laser ultrasonics open up entirely new frontiers for in-situ, non-destructive mechanical characterisation of dry and liquid-functionalised porous materials.

scholarly journals In-Situ Evaluation of the Protectivity of Coatings Applied to Metal Cultural Artefacts Using Non-Destructive Electrochemical Measurements

2021 ◽  
Vol 2 (1) ◽  
pp. 120-132
Author(s):  
Douglas J. Mills ◽  
Katarzyna Schaefer ◽  
Tomasz Wityk
Keyword(s):  
Baltic Sea ◽  
Electrochemical Noise ◽  
Organic Coating ◽  
Noise Measurement ◽  
The Baltic Sea ◽  
Coating Type ◽  
The Baltic ◽  
Non Destructive ◽  
Electrolytic Resistance

Electrochemical Noise Measurement (ENM) and DC electrolytic resistance measurement (ERM) can be used to assess the level of protectiveness provided by an organic coating (paint or varnish) to the underlying metal. These techniques also have applicability to the thinner, transparent type of coatings used to protect archaeological artefacts. Two studies are presented here demonstrating how ERM and ENM techniques can be applied in artefact preservation. The similarity of the techniques, both of which are a measure of resistance, means results can be considered to be analogous. The first study investigated the use of ERM to determine the protection levels provided by typical coatings in order to develop a database of coating type and application for objects, for specific environments. The second study used ENM to evaluate coatings which had been applied to historic artefacts recovered from shipwrecks in the Baltic Sea and displayed inside the museum or kept in the museum store area. The studies showed the usefulness of both techniques for determining the level of protection of a coating and how a better performing coating can be specified if a pre-existing coating on an artefact has been found to be unsuitable.

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