Verification of the Ultrasonic Qualification for Structural Integrity of Partially Concrete Embedded Steel Elements

2009 ◽  
Vol 65 ◽  
pp. 69-78 ◽  
Author(s):  
J. Alfredo López ◽  
Francisco J. Carrión ◽  
Juan A. Quintana ◽  
Didier Samayoa-Ochoa ◽  
María G. Lomelí ◽  
...  
Keyword(s):  
Grain Size ◽  
Structural Integrity ◽  
Fatigue Cracks ◽  
Good Condition ◽  
Ultrasonic Inspection ◽  
Structural Elements ◽  
Ultrasonic Evaluation ◽  
Statistical Mechanical ◽  
Microstructural Integrity ◽  
Non Destructive

Failure of one upper anchorage element in a cable-stayed bridge and its consequent analysis concluded that the main cause of the failure was a deficient heat treatment that resulted in large micro structural grain size and low fracture toughness, vulnerable to fatigue damage. Previous research studies demonstrated that ultrasonic evaluation could provide some insight of the microstructural integrity by correlating the ultrasonic response to the grain size. Thus, this technique was used to inspect the 112 elements in service in the bridge and 16 were qualified as structurally deficient, without direct verification of the grain size, since these elements were partially embedded in the concrete structure. Late rehabilitation of the bridge considered the replacement of the 16 structural deficient anchorage elements, plus 4 elements qualified in good condition, to complete a reliability analysis for the remaining 92 elements from the statistical mechanical properties of the removed pieces. Rehabilitation made possible the confirmation of the initial diagnosis made by ultrasonic inspection and fatigue cracks were identified in some elements. This study demonstrated that the ultrasonic non destructive evaluation is highly reliable for structural integrity qualification of steel structural elements partially embedded in concrete.

Introduction of Hot Isostatically Pressed, Reactor Coolant System Components in PWR Plant

2010 ◽  
Author(s):  
John L. Sulley ◽  
Ian Hookham ◽  
Barry Burdett ◽  
Keith Bridger
Keyword(s):  
Nuclear Reactor ◽  
Structural Integrity ◽  
Full Range ◽  
Ultrasonic Inspection ◽  
Grain Structure ◽  
Reactor Plant ◽  
Strategic Sourcing ◽  
Staged Approach ◽  
Route Cost ◽  
Non Destructive

This paper presents an overview of the work undertaken by Rolls-Royce to introduce Hot Isostatically Pressed (HIP) components into Pressurised Water Reactor plant, and also results of non-destructive and destructive examinations of a thick-walled pressure vessel. It presents the work from a design justification/manufacturing quality assurance perspective, rather than from a pure metallurgical perspective. Although the HIP process is not new, it was new in its application to Rolls-Royce designed nuclear reactor plant. As a consequence, Rolls-Royce has implemented an evolving, staged approach, starting with HIP bonding of solid valve seats into small bore valve pressure boundaries. This was followed by powder HIP consolidation of leak-limited, thin-walled toroids, and has culminated in the powder HIP consolidation of thick-walled components. The paper provides an overview of each of these stages and the approach taken with respect to justification. Mechanical testing and metallurgical examination results of sample material taken from different sections of a thick-walled component are presented. A full range of test results is provided covering, as examples: tensile, charpy and sensitization susceptibility. Differences in weldability between the HIPed and the previous forged form are also documented. The paper describes the benefits that Rolls-Royce has realised so far through the introduction of HIPed component. Structural integrity benefits are described, such as improved grain structure, mechanical properties, and ultrasonic inspection. Project-based benefits are also described, such as provision of an alternative strategic sourcing route, cost and lead-time reductions.

scholarly journals Comprehensive condition assessment program on the fire damaged structure - a project case in Singapore

2018 ◽  
Vol 195 ◽  
pp. 02034
Author(s):  
Gunawan Budi Wijaya
Keyword(s):  
Structural Integrity ◽  
Concrete Slab ◽  
Good Condition ◽  
Concrete Surface ◽  
Condition Assessment ◽  
Rehabilitation Program ◽  
Reinforced Concrete Slab ◽  
Average Residual ◽  
Post Tension ◽  
Non Destructive

A fire damaged structure at the eastern part of Singapore was assessed. Some concrete spalling exposing corroded steel reinforcements were noted on the post tensioned concrete beam and reinforced concrete slab, raising a concern about the structural integrity of the overall floor. A comprehensive condition assessment was performed on the affected structural elements to determine the extent of the damage, which included some on-site destructive and non-destructive tests as well as some laboratory testing on the collected concrete and steel samples. Testing data revealed that the concrete was still in consistently good condition with the average residual compressive strength of 36.51MPa. Petrographic examinations suggested that the top 5mm of the concrete surface might be exposed to a temperature not more than 450o C. The steel reinforcement and post tension strands were found to be still in good condition as well. The findings of this assessment will then be used for further structural assessment to determine the most effective structural rehabilitation program.

Qualification of a Combined Ultrasonic Inspection Tool for Detection and Sizing of Circumferential Weld Cracks in Offshore Pipelines

2014 ◽  
Author(s):  
Herbert Willems ◽  
Hans Petter Bjørgen ◽  
Thor-Ståle Kristiansen ◽  
Guus Wieme
Keyword(s):  
Fatigue Testing ◽  
Fatigue Cracks ◽  
Ultrasonic Inspection ◽  
Probability Of Detection ◽  
Offshore Pipelines ◽  
Fast Screening ◽  
Standard Application ◽  
Weld Area ◽  
Pulse Echo ◽  
Non Destructive

The target of inline crack inspection is normally related to the detection of axial cracks (weld cracks, SCC etc.) as axial cracks are usually expected under typical loading conditions in pressurized pipe. Ultrasonic crack inspection tools for this type of cracks have been available for over 20 years and have become a standard application in the ILI business. However, under certain conditions circumferential cracking may occur and the inspection technique needs to be modified accordingly. Especially under offshore conditions with limited pipeline accessibility not only the early detection of crack-like defects is required but also a precise depth sizing is important in order to minimize the risk of crack-related pipeline failure. In order to ensure a high probability of detection together with state-of-the-art depth sizing, a 10″ inline inspection tool was developed for the detection of circumferentially orientated weld cracks. The tool combines the advantages of the pulse-echo technique on the detection side with the excellent capabilities of the TOFD (time-of-flight-diffraction) technique for accurate sizing. Both techniques are implemented into a tethered tool where the pulse-echo unit serves for fast screening while the relatively slow TOFD-unit is used for sizing of any detected crack-like features. In order to qualify the new tool for a special offshore application (inspection of circumferential cracking at welded anode pads) extensive testing was performed using a 10″ test pipeline prepared by Statoil. The test line contained 64 artificial weld defects for reference purposes as well as an unknown number of fatigue cracks in the weld area which were generated by fatigue testing of the corresponding pipes. The tests were full blind tests with no advance knowledge on locations and sizes of the cracks. The sizes of the fatigue cracks (length, depth) were determined by destructive examinations carried out after inline testing. The subsequent comparison of the destructive results with the non-destructive results showed that the specification of the tool with regard to detection and sizing was fully met. In the paper, the inspection concept and the setup of the new tool are described, and the results of the qualification tests are presented.

Mechanical Properties of Wood and Timber Bridge Evaluation

2014 ◽  
Vol 587-589 ◽  
pp. 1381-1385
Author(s):  
Ling Ling Yu ◽  
Jie Jun Wang ◽  
Te Huang
Keyword(s):  
Mechanical Properties ◽  
Structural Integrity ◽  
Strength Properties ◽  
Structural Elements ◽  
Bridge Evaluation ◽  
Bridge Structures ◽  
And Performance ◽  
Inspection Techniques ◽  
Non Destructive ◽  
Timber Bridges

Wood possesses material properties that may be significantly different from other materials normally encountered in structural design. It is necessary for the engineer to have a general understanding of the properties and characteristics that affect the strength and performance of wood in bridge applications. This paper discusses the mechanical properties of wood, including elastics properties and strength properties. Timber bridge are often exposed to harsh environment conditions. Over time, this exposure can lead to deterioration. In turn, this deterioration may lead to a loss of structural integrity that is detrimental to the structure and its users. Timber structural elements are susceptible to degradation due to environmental and loading conditions. A variety of inspection techniques can be employed to locate damage and decay in timber members in order to maintain structural performance. Methods of non-destructive techniques for timber bridges are getting more and more important. This paper presents several non-destructive methods to timber bridge structures.

A Review of Process Tomography Application in Inspection System

2014 ◽  
Vol 70 (3) ◽  
Author(s):  
Yasmin Abdul Wahab ◽  
Ruzairi Abdul Rahim ◽  
Mohd Hafiz Fazlul Rahiman ◽  
Herlina Abdul Rahim ◽  
Suzanna Ridzuan Aw ◽  
...  
Keyword(s):  
Electrical Impedance ◽  
Optical Tomography ◽  
Good Condition ◽  
Future Research ◽  
Inspection System ◽  
Ultrasonic Tomography ◽  
Impedance Tomography ◽  
X Ray ◽  
Process Tomography ◽  
Non Destructive

The inspection system is crucial to ensure the system is always in a good condition. A technique that can be used for inspection system is process tomography. By promising non-destructive approach; various types of process tomography applied in civil, manufacturing and electrical applications. The purpose of this paper is to review the types of process tomography such as ultrasonic tomography, x-ray tomography, optical tomography, electrical resistance tomography, and electrical impedance tomography that had been applied to the inspection system. Variety techniques of inspection based on those sensors briefly discussed in this paper. The result showed that the process tomography expanded tremendously in the inspection system. Finally, a potential future research on the inspection system in the civil application proposed in this paper.

Non-destructive magnetic measurement of steel grain size

1976 ◽  
Vol 9 (3) ◽  
pp. 117-120 ◽  
Author(s):  
S. Titto ◽  
M. Otala ◽  
S. Säynäjäkangas
Keyword(s):  
Grain Size ◽  
Magnetic Measurement ◽  
Non Destructive

Vibration-Based Crack Detection in L-Frames

2014 ◽  
Vol 658 ◽  
pp. 261-268
Author(s):  
Jean Louis Ntakpe ◽  
Gilbert Rainer Gillich ◽  
Florian Muntean ◽  
Zeno Iosif Praisach ◽  
Peter Lorenz
Keyword(s):  
Strain Energy ◽  
Crack Detection ◽  
Natural Frequencies ◽  
Vibration Modes ◽  
Structural Elements ◽  
Element Analysis ◽  
Accurate Localization ◽  
Mathematical Expressions ◽  
Measurement Results ◽  
Non Destructive

This paper presents a novel non-destructive method to locate and size damages in frame structures, performed by examining and interpreting changes in measured vibration response. The method bases on a relation, prior contrived by the authors, between the strain energy distribution in the structure for the transversal vibration modes and the modal changes (in terms of natural frequencies) due to damage. Using this relation a damage location indicator DLI was derived, which permits to locate cracks in spatial structures. In this paper an L-frame is considered for proving the applicability of this method. First the mathematical expressions for the modes shapes and their derivatives were determined and simulation result compared with that obtained by finite element analysis. Afterwards patterns characterizing damage locations were derived and compared with measurement results on the real structure; the DLI permitted accurate localization of any crack placed in the two structural elements.

A Fresh Insight into Film Morphology Measurement Techniques for Advanced Ulsi Manufacturing

1993 ◽  
Vol 309 ◽  
Author(s):  
Seshadri Ramaswami
Keyword(s):  
Grain Size ◽  
Integrated Circuit ◽  
Measurement Techniques ◽  
Film Morphology ◽  
Integrated Circuit Fabrication ◽  
Circuit Fabrication ◽  
Non Destructive ◽  
Fresh Insight ◽  
Insight Into

AbstractA laser based non-destructive technique has been used to study the morphology of sputterdeposited aluminum alloy films. The data emanating from the Therma-wave Imager that makes use of this principle, has been correlated with reflectivity, grain size and micro-roughness of the film. In addition, through the use of a case study, this paper demonstrates the utility of this application as an in-line monitor in an integrated circuit fabrication line.

Study of the residual imperfections using methods of probability theory

2021 ◽  
Vol 87 (9) ◽  
pp. 44-49
Author(s):  
D. A. Kuzmin
Keyword(s):  
Probability Theory ◽  
Generalized Equation ◽  
Structural Elements ◽  
Non Destructive Testing ◽  
Operational Control ◽  
Destructive Testing ◽  
Control Procedures ◽  
Non Destructive ◽  
A Current

Discontinuities in the products that occur during manufacture, mounting or upon operation can be missed during non-destructive testing which do not provide their complete detectability at a current level of the technology. Therefore, it is necessary to take into account that certain structural elements may have discontinuities of significant dimensions. We present the results of using the methods of probability theory in studying the residual imperfections that remains in the structure after non-destructive control and repair of the previously identified defects. We used the results of operational control of units carried out by ultrasonic and radiographic methods. We present a method for determining a multifactorial coefficient that takes into account the detectability of defects, the number of control procedures and the errors in the instrumentation and methodological support, as well as a generalized equation for the probability distribution of detecting discontinuities. The developed approach provides assessing of the level of damage to the studied objects, their classification proceeding from the quantitative data and determination of the values of postulated discontinuities for deterministic calculations. The results obtained can be used to improve the methods of monitoring NPP facilities.

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