• 제목/요약/키워드: nondestructive evaluation

검색결과 849건 처리시간 0.035초

교량유지관리시스템에 있어서 비파괴 시험의 효율적 활용 방안 (Use of Nondestructive Evaluation Methods in Bridge Management Systems)

  • 심형섭
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
    • /
    • pp.1291-1296
    • /
    • 2000
  • A basis for the direct use of data from nondestructive evaluation methods in bridge management systems is presented. Bridge management systems use integer-valued condition ratings to recognize conditions of bridge elements, to model progression of deterioration, and to determine repair needs. Data from nondestructive evaluation methods can inform management systems on the extent of damage, on the initiation of deterioration processes, and on the exposure of bridge elements to aggressive agents. In addition, data obtained through nondestructive evaluation methods allow the formation of models of specific deterioration process. The use of these data in bridge management systems requires redefinition of condition ratings together with the creation of procedures for automated interpretation of data. By these action, nondestructive evaluation methods are directly used to assign condition ratings, and condition ratings are made into terse form of NDE data that are compatible with present day bridge management systems. This paper reports work in progress to strategic use of nondestructive evaluation methods in bridge management system.

Evaluation of Structural Integrity and Performance Using Nondestructive Testing and Monitoring Techniques

  • Rhim, Hong-Chul
    • 한국지진공학회논문집
    • /
    • 제2권3호
    • /
    • pp.73-81
    • /
    • 1998
  • In this paper, the necessity of developing effective nondestructive testing and monitoring techniques for the evaluation of structural integrity and performance is described. The evaluation of structural integrity and performance is especially important when the structures and subject to abrupt external forces such as earthquake. A prompt and extensive inspection is required over a large area of earthquake-damaged zone. This evaluation process is regarded as a part of performance-based design. In the paper, nondestructive testing and monitoring techniques particularly for concrete structures are presented as methods for the evaluation of structural integrity and performance. The concept of performance-based design is first defined in the paper followed by the role of evaluation of structures in the context of overall performance=based design concept. Among possible techniques for the evaluation, nondestructive testing methods for concrete structures using radar and a concept of using fiber sensor for continuous monitoring of structures are presented.

  • PDF

A Simulation Tool for Ultrasonic Inspection

  • Krishnamurthy, Adarsh;Mohan, K.V.;Karthikeyan, Soumya;Krishnamurthy, C.V.;Balasubramaniam, Krishnan
    • 비파괴검사학회지
    • /
    • 제26권3호
    • /
    • pp.153-161
    • /
    • 2006
  • A simulation program SIMULTSONIC is under development at CNDE to help determine and/or help optimize ultrasonic probe locations for inspection of complex components. SIMULTSONIC provides a ray-trace based assessment for immersion and contact modes of inspection. The code written in Visual C++ operating in Microsoft Windows environment provides an interactive user interface. In this paper, a description of the various features of SIMULTSONIC is given followed by examples illustrating the capability of SIMULTSONIC to deal with inspection of canonical objects such as pipes. In particular, the use of SIMULTSONIC in the inspection of very thin-walled pipes (with 450 urn wall thickness) is described. Ray trace based assessment was done using SIMULTSONIC to determine the standoff distance and the angle of oblique incidence for an immersion mode focused transducer. A 3-cycle Hanning window pulse was chosen for simulations. Experiments were carried out to validate the simulations. The A-scans and the associated B-Scan images obtained through simulations show good correlation with experimental results, both with the arrival time of the signal as well as with the signal amplitudes.

수소손상 검출과 평가기술 (Detection and Evaluation Technique of Hydrogen Attack)

  • 원순호;현양기;이종오;조경식;이재도
    • 비파괴검사학회지
    • /
    • 제22권1호
    • /
    • pp.32-37
    • /
    • 2002
  • 산업현장에서 수소는 설비를 손상시킬 수 있는 주원인 중의 하나이며, 종종 설비를 파괴시키는 사고를 발생시킨다. 수소손상에 의한 결정립계의 공동 또는 미세균열은 강재의 파괴인성과 강도를 떨어뜨리는 원인이 되고, 따라서 과거 제한적인 방법으로 수소손상을 평가하기 위한 시도가 수행되었다. 본 연구에서는 초음파를 적용하여 수소손상을 검출하고 평가하기 위한 연구를 수행하였다. 미세조직 시험에 의해 확인된 시험편을 이용하여 초음파의 속도와 감쇠계수를 구한 결과, 수소손상에 의해서 초음파 속도는 감소하고 감쇠는 현저하게 증가하는 것으로 나타났다. 이러한 결과를 바탕으로 수소손상을 검출하기 위한 신뢰성 있는 평가법을 제시하였다.

공명초음파 분광법에 의한 광학기기용 렌즈의 비파괴 검사 (Nondestructive Examination of Optical Lens by Resonant Ultrasound Spectroscopy)

  • 김성훈;박상국;김영남;양인영
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 2004년도 추계학술대회 논문집
    • /
    • pp.257-262
    • /
    • 2004
  • As optical connectors dominate the performance of optical transmitters or receivers, they need an ultra-precise processing and are composed of optical fibers, ferrule and optical glass lenses. Therefore, this study suggests a nondestructive evaluation technique or a system using resonant ultrasound spectroscopy to evaluate flaws in a optical glass lens. It also conducted a nondestructive evaluation for flaws that are commonly found in a optical glass lens and reviewed the results.

  • PDF

QUALITY EVALUATION OF TECHNOLOGY OF AGRICULTURAL PRODUCTS

  • Chen, Pictiaw
    • 한국농업기계학회:학술대회논문집
    • /
    • 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
    • /
    • pp.171-190
    • /
    • 1996
  • Quality evaluation of agricultural products has been a subject of interest to many researches for many years. As a results, several nondestructive techniques for quality evaluation of agricultural products have been developed. These methods are based on the detection of various physical properties that correlate well with certain quality factors of the products. This paper presents an overview of various quality evaluation techniques that are based on one of the following properties : density, firmness , vibration characteristic , X-ray and gamma ray transmission, optical reflectance and transmission , electrical properties, aromatic volatile emission, and nuclear magnetic resonance (NMR). The sophistication of nondestructive methods has evolved rapidly with modern technologies. The use of various modern image acquisition techniques, such as solid state TV camera, line-scan camera, X-ray scanning , ultrasonic scanning and NMR imaging, in conjunction with image-processing te hniques has provided new opportunities for researchers to develop many new and improved techniques for nondestructive quality evaluation of agricultural products.

  • PDF