scholarly journals On-site corrosion monitoring experience in concrete structures: potential improvements on the current-controlled polarization resistance method

2021 ◽  
Vol 71 (344) ◽  
pp. e265
Author(s):  
J. E. Ramón ◽  
Á. Castillo ◽  
I. Martínez
Keyword(s):  
Concrete Structures ◽  
Real Life ◽  
Corrosion Monitoring ◽  
Polarization Current ◽  
Destructive Testing ◽  
Electrochemical Current ◽  
Current Confinement ◽  
And Control ◽  
Non Destructive

The need for proactive maintenance of reinforced concrete structures with non-destructive testing (NDT) is less disputable today than ever. One of the most promising strategies in this regard is the in-situ measurement of the reinforcement corrosion rate. This study explored the reliability of modulated current confinement method (hereafter MCC) based on a review of in-situ measurements made with that technique in real-life structures over a 13-year period. The most prominent problems detected included defective confinement of the polarization current in low-resistivity environments and over-polarization of passive reinforcement. The findings, which showed enhancement of MCC reliability to depend on improving the electrochemical current regulation and control methodologies presently in place, are being applied to improve the design of the next generation of corrosion meters.

scholarly journals Study of Lamb Waves for Non-Destructive Testing Behind Screens

2018 ◽  
Vol 170 ◽  
pp. 03005 ◽  
Author(s):  
P. Kauffmann ◽  
M.-A. Ploix ◽  
J.-F. Chaix ◽  
C. Gueudré ◽  
G. Corneloup ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Lamb Waves ◽  
Nuclear Industry ◽  
Liquid Sodium ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Leaky Lamb Waves ◽  
Short Time ◽  
And Control ◽  
Non Destructive

The inspection and control of sodium-cooled fast reactors (SFR) is a major issue for the nuclear industry. Ultrasonic solutions are under study because of the opacity of liquid sodium. In this paper, the use of leaky Lamb waves is considered for non-destructive testing (NDT) on parallel and immersed structures assimilated as plates. The first phase of our approach involved studying the propagation properties of leaky Lamb waves. Equations that model the propagation of Lamb waves in an immersed plate were solved numerically. The phase velocity can be experimentally measured using a two dimensional Fourier transform. The group velocity can be experimentally measured using a short-time Fourier transform technique. Attenuation of leaky Lamb waves is mostly due to the re-emission of energy into the surrounding fluid, and it can be measured by these two techniques.

scholarly journals HIGH RISE FRAME BUILDING CONSTRUCTION WITH REGARD TO DEFECTS IN MONOLITHIC BASE SLAB

2020 ◽  
Vol 22 (5) ◽  
pp. 160-172
Author(s):  
S. V. Yushchube ◽  
I. I. Podshivalov ◽  
G. I. Tayukin
Keyword(s):  
Defect Formation ◽  
Strength Properties ◽  
Building Construction ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
High Rise ◽  
Frame Building ◽  
Concrete Layer ◽  
Non Destructive

The paper analyzes the influence of defects detected in a monolithic base slab on the possibility of its further application in the construction of a 25-storey high-rise frame building. Non destructive testing and vertical core sampling techniques are used for the detailed analysis of the monolithic base slab. It is found that irregularities in the procedure during winter concreting of the base slab decreases the strength properties of concrete and provides the defect formation in the slab structure, namely delamination of the lower protective concrete layer and uncovering of working reinforcement. For the safe use of the 25-storey high-rise building, the base slab is proposed to be strengthened by adding in-situ reinforced concrete layer 100 cm thick.

Standardisation of X-Ray Powder Diffraction Methods

2004 ◽  
Vol 443-444 ◽  
pp. 31-34
Author(s):  
Giovanni Berti ◽  
Rob Delhez ◽  
S. Norval ◽  
B. Peplinski ◽  
E. Tolle ◽  
...  
Keyword(s):  
Technical Committee ◽  
Non Destructive Testing ◽  
X Ray Diffraction ◽  
Destructive Testing ◽  
X Ray ◽  
Standard Documents ◽  
And Control ◽  
Non Destructive ◽  
Research Centres

This paper outlines the standardisation process for the XRPD method that is currently being considered by a Working Group (WG10) of Technical Committee 138 "Non-destructive Testing" of the European Committee for Standardisation CEN. Several Standard Documents are on the verge of being released. These documents concern the general principles of (X-ray) diffraction, its terminology, and the basic procedures applied. Another document concerns the instruments used and it offers procedures to characterise and control the performance of an X-ray diffractometer properly. It is intended to issue Standard Documents on specific methods, e.g. determination of residual stresses. In fact work is in progress on this subject. The Standard Documents can be used by industry, government organisations, and research centres with activities related to safety, health and the environment, as well as for educational purposes.

scholarly journals NDT ASSESSMENT OF EXISTING CONCRETE STRUCTURES: SPATIAL ANALYSIS OF REBOUND HAMMER RESULTS RECORDED IN-SITU

2015 ◽  
Vol 7 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Adorján Borosnyói
Keyword(s):  
Spatial Analysis ◽  
Surface Hardness ◽  
Hardness Measurement ◽  
Optical Recording ◽  
Destructive Testing ◽  
Rebound Hammer ◽  
Schmidt Rebound Hammer ◽  
The Impact ◽  
Non Destructive

A comparative spatial analysis of surface hardness of structural concrete is introduced. Main objective of the paper is to make a repeatability comparison of three types of the still most popular non-destructive testing devices for concrete: L-type original Schmidt rebound hammer, N-type original Schmidt rebound hammer and N-type Silver Schmidt rebound hammer. Results indicate that the surface hardness measurement uncertainty is related to the weight of the hammer mass and is apparently not related to the impact energy of the rebound hammer devices. It is observed that the measure of surface hardness for the Silver Schmidt rebound hammer (Q-value) does not have positive correlation to the original rebound index (R). Results indicate the best performance of the N-type original Schmidt rebound hammer in terms of stability and normality of data. Geostatistical analysis of the measured data (in terms of empirical semivariograms) highlights different statistical behaviour for the mechanical recording rebound hammers and for the electro-optical recording rebound hammer.

Lifetime Management of EDF PWR Pressure Vessels and Pipings

2004 ◽  
Author(s):  
F. Hedin ◽  
J. C. Legendre
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Pressure Vessels ◽  
Destructive Testing ◽  
Key Points ◽  
Cast Stainless Steel ◽  
Non Destructive

Lifetime management of EDF PWR vessels and pipings are one of the main technical key points of safety and competitivness. This paper describes the EDF global approach in this field, which is applied to the nuclear fleet i.e 58 nuclear power plants, and particularly to the first 34 three loops, as far as lifetime is concerned: • operating procedures and routine maintenance, special maintenance and ten years safety reassessment, • engineering analysis, based on feed back experience, scientific knowledge, degradations mechanisms, causes and consequences management, • operating loadings decrease, • complementary deterministic and cost-benefit analysis, • fit for service justifications, • anticipation strategy to prepare future, based on Non Destructive Testing investigations, ability to repair and/or to replace components, in situ expertises, ... Some examples are given: lifetime management of reactor vessels heads and bottom penetrations of pressure vessels, fit for service of cast stainless steel primary pipings, primary nozzles and auxiliary pipings special maintenance.

Sign in / Sign up

Export Citation Format

Share Document