비파괴검사학회지 (Journal of the Korean Society for Nondestructive Testing)

  • 제34권2호
  • /
  • Pages.148-154
  • /
  • 2014
  • /
  • 1225-7842(pISSN)
  • /
  • 2287-402X(eISSN)
한국비파괴검사학회 (The Korean Society for Nondestructive Testing)
권호 표지
DOI QR코드

DOI QR Code

압축하중을 받는 마름모 판에 대한 영상처리기법을 이용한 광탄성 응력 해석

Photoelastic Stress Analysis for a Rhombus Plate under Compressive Load Using Image Processing Technique

  • 류관용 (군산대학교 대학원 기계공학과) ;
  • 김명수 (군산대학교 전자공학과) ;
  • 백태현 (군산대학교 기계자동차공학부)
  • 투고 : 2014.01.20
  • 심사 : 2014.04.14
  • 발행 : 2014.04.30
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

광탄성기법은 주응력 차이와 주응력 방향을 측정할 수 있는 편리한 기법이다. 일반적인 재래식 광탄성기법에서는 광탄성 파라미터를 측정하기 위해서는 수작업으로 한 지점씩 측정해야 하므로 많은 시간이 소요되며 광탄성 데이터 측정과 식별에 숙련이 필요하다. 프린지 위상이동법은 최근에 개발되어 광역학분야에서 프린지 데이터를 측정하고 해석하기 위해 편리하게 사용되고 있다. 이 논문은 photoflex (우레탄고무일종) 재질의 마름모 평판 중심점을 지나는 수평선상의 응력분포를 측정하기 위한 실험적 연구이다. 마름모 평판시편의 수평선상에서는 등경프린지 또는 주응력 방향이 일정하므로 4-버켓 위상이동법의 적용이 가능하다. 이 방법은 원형편광기에서 검광판을 $0^{\circ}C$, $45^{\circ}C$, $90^{\circ}C$, 그리고 $135^{\circ}C$ 회전시켜 얻은 4개의 광탄성 프린지를 필요로 한다. 이 방법으로 측정된 실험 결과는 유한요소해석 결과와 정량적으로 비교하였으며, 두 결과가 근접하게 일치되었다.

Photoelasticity is a useful technique for obtaining the differences and directions of principal stresses in a model. In conventional photoelasticity, the photoelastic parameters are measured manually point by point. Identifying and measuring photoelastic data is time-consuming and requires skill. The fringe phase shifting method was recently developed and has been found to be convenient for measuring and analyzing fringe data in photo-mechanics. This paper presents an experimental study on the stress distribution along a horizontal line that passes the central point of a rhombus plate made of Photoflex (i.e., type of urethane rubber). The isoclinic fringe and/or principal stress direction is constant on this horizontal line, so a four-bucket phase shifting method can be applied. The method requires four photoelastic fringes that are obtained from a circular polariscope by rotating the analyzer at $0^{\circ}C$, $45^{\circ}C$, $90^{\circ}C$ and $135^{\circ}C$. Experimental measurements using the method were quantitatively compared with the results from FEM analysis; the results from the two methods showed comparable agreement.

키워드

참고문헌

  1. T. H. Baek, M. S. Kim and L. Chen, "Comparison of full-field atresses around an inclined crack tip by using fringe data of finite element method with photoelastic experiment," Journal of the Korean Society for Nondestructive Testing, Vol. 29, No. 6, pp. 557-562 (2009)
  2. J. W. Dally and W. F. Riley, "Experimental Stress Analysis," 3rd Ed., McGraw-Hill, Inc. (1991)
  3. C. P. Burger, "Chapter 5 Photoelasticity in Handbook on Experimental Mechanics," 2nd Ed., Edited by A. S. Kobayashi, Society for Experimental Mechanics, Inc., Bethel, Connecticut, pp. 165-266 (1993)
  4. G. L. Cloud, "Optical Methods of Engineering Analysis," Cambridge University Press (1995)
  5. T. H. Baek, M. S. Kim and S. H. Cho, "Measurement of isochromatic fringe distribution of a TV glass panel by use of photoelastic 4-step phase shifting method", Journal of the Korean Society for Nondestructive Testing, Vol. 25, No. 1, pp. 1-8 (2005)
  6. T. H. Baek, M. S. Kim, Y. Morimoto and M. Fujigaki, "Separation of isochromatics and isoclinics from photoelastic fringes in a circular disk by phase measuring technique," KSME International Journal, Vol. 16, No. 2, pp. 1207-1213 (2002)
  7. T. H. Baek and M. S. Kim, "Computer Simulation of Photoelastic Fringe Patterns for Stress Analysis," Systems Modeling and Simulation: Theory and Applications, Lecture Notes in Computer Science, Issue Vol. 3398, pp. 214-221 (2005)
  8. T. H. Baek, "Photoelastic stress analysis by use of hybrid technique and fringe phase shifting method," Journal of Experimental Mechanics, Vol. 21, No. 1, pp. 87-95 (2006)
  9. L. Chen and T. H. Baek, "Accurate determination of stress intensity factor of a central crack by digital photoelasticity," Modern Physics Letters B, Vol. 22, No. 11, pp. 863-868 (2008) https://doi.org/10.1142/S0217984908015516
  10. T. H. Baek, L. Chen and D. P. Hong, "Hybrid determination of mixed-mode stress intensity factors on discontinuous finite-width plate by finite element and photoelasticity," Journal of Mechanical Science and Technology, Vol. 25, No. 10, pp. 2535-2543 (2011) https://doi.org/10.1007/s12206-011-0740-1
  11. T. H. Baek and M. S. Kim, "Measurement of stress intensity factors of inclined crack in a tensile plate by using hybrid photoelastic technique combined with FEA data," International Journal of Green Engineering and Management, Vol. 2, No. 1, pp. 1-9 (2013)
  12. T. H. Baek, "Development image processing technique for photoelastic isochromatic fringe sharpening," Journal of the Korean Precision Engineering, Vol. 10, No. 3, pp. 220-230 (1993)
  13. T. H. Baek and J. C. Lee, "Development of image processing technique for photoelastic fringe analysis," Trans. of KSME, Vol. 18, No. 10, pp. 2577-2584 (1994)
  14. A. Asundi, "Phase shifting in photoelasticity," Experimental Techniques, Vol. 7, No. 1, pp. 19-23 (1993)
  15. Sharples Stress Engineers Ltd. Unit 29, Old Mill Industrial Est., School Lane, Bamber Bridge, Preston, Lancs, U. K. PR5 6SY
  16. ANSYS 14, www.ansys.com, ANSYS, Inc.