Traceability of Optical Techniques for Strain Measurement

Abstract:

Strain is a dimensionless quantity derived from displacement. To measure strain, devices such as resistive strain gauges and extensometers but also imaging methods are applied in engineering and experimental mechanics. The lack of standards and reference materials related to optical methods of strain measurement is tackled by the SPOTS project. It is intended to make full use of the modularity of different methods in order to develop a unified approach to standardisation. In this contribution we focus on the problem of traceability of optical strain measurement values and underline the role of strain measurement standards. We clarify the terminology and outline routes for traceability in analogy to widespread procedures for single value strain measurements.

• Periodical: Applied Mechanics and Materials (Volumes 3-4)
• Pages: 391-396
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.3-4.391
• Online since: August 2006
• Authors: Erwin Hack, Richard L. Burguete, E.A. Patterson
• Keywords: Calibration, Displacement Measurement, Interferometry, Measurement Standards, Optical Techniques, Standardisation, Strain Measurement

References

[1] P.K. Rastogi: Optical Measurement Techniques and Applications (Artech House, 1997).

[2] SPOTS: Standardisation project for optical techniques of strain measurement, EU contract no. G6RD-CT-2002-00856, see http: /www. opticalstrain. org.

[3] M. Whelan, E. Hack, T. Siebert, R. Burguete, E.A. Patterson, Q. Saleem: On the calibration of optical full-field strain measurement systems, paper 62, Proc. Int. Conf. Advances in Experimental Mechanics, Southampton, UK, 6-8 September (2005).

DOI: 10.4028/www.scientific.net/amm.3-4.397

[4] E.A. Patterson, M. Whelan, E. Hack, T. Siebert, R. Burguete, Q. Saleem: Standard test for the evaluation of optical strain measurement systems, paper 63, Proc. Int. Conf. Advances in Experimental Mechanics, Southampton, UK, 6-8 September (2005).

DOI: 10.4028/www.scientific.net/amm.3-4.403

[5] R.B. Watson: Calibration techniques for extensometry: possible standards of strain measurement. Journal of Testing and Evaluation vol. 21 (1993), no. 6: 515-21.

DOI: 10.1520/jte11802j

[6] Measurement traceability and calibration in the mechanical testing of metallic materials, UKAS Publication ref: LAB 24, (2000).

[7] V.S. Volobuev, N.P. Klokova, L.I. Kosov, V.D. Kamkova, V.P. Minakov, V.I. Tikhomirov: Standard stand for determining the metrological characteristics of resistance strain gages. Measurement Techniques vol. 43 (2000), 12: 1052-6.

DOI: 10.1023/a:1010939718310

[8] ISO IEC 17025: 1999: General requirements for the competence of testing and calibration laboratories.

[9] ISO 10012: 2003: Measurement Management Systems - Requirements for measurement processes and measuring equipment.

[10] International vocabulary of basic and general terms in metrology (VIM), 2nd edition, ISO/IEC/OIML/BIPM, Geneva, (1993).

[11] ILAC-G2: 1994: Traceability of Measurements.

[12] EAL-P11: 1997: Validation of Test Methods.

[13] E. Hack, G. Sims, D. Mendels, Traceability, reference materials and standardised tests in optical strain measurement, in: Advances in Experimental Mechanics, C. Pappalettere, Ed., McGraw-Hill, Milan, 2004, 693-694.

[14] R. Kästle, E. Hack, and U. Sennhauser: Multiwavelength shearography for quantitative measurements of two-dimensional strain distributions. Appl. Opt. vol. 38 (1999)1, 96-100.

DOI: 10.1364/ao.38.000096

[15] ASTM E 2208-02: 2002: Standard guide for evaluating non-contacting optical strain measurement systems.

[16] ISO/TAG4/WG3, Guide to the Expression of Uncertainty in Measurement (GUM), 1995, identical with EN13005: 1999: Guide to the Expression of Uncertainty in Measurement.

[17] ASTM F1364-03: 2003: Practice for use of a calibration device to demonstrate the inspection capability of an interferometric laser imaging nondestructive tire inspection system.

DOI: 10.1520/f1364-03r10

[18] Improving the Reliability, Quality and Cost-Effectiveness of the Inspection of Safety Critical Structures, Brite Euram project BRE20160, 1992-(1995).

[19] DIN V 54180-3: 1997-03: Zerstörungsfreie Prüfung - Shearografie - Teil 3: Prüfung von Rohrleitungen.