Developing Standards for Optical Methods of Strain Measurement

摘要

In 1999 under the auspices of VAMAS, an international Technical Working Area on Full-field Optical Methods of Strain Measurement (TWA26) was formed. TWA26 was charged with coordinating pre-normative research that would ultimately lead to the development of international standards in this area. In 2003 a consortium of eleven organizations from eight countries began an EU-funded research project to develop reference materials for optical techniques of in-plane strain measurement. This research will be completed at the end of 2005 and will generate a draft Technology Trend Assessment (TTA) which will be reviewed by VAMAS TWA26 before being submitted to ISO for publication. This will represent a major step towards the development of an international standard in the field of optical strain measurement and hence will provide a certification route for those interested in using such methods to validate simulations and to quantify uncertainty. Progress to date includes the design of a reference material for the calibration of optical systems for strain measurement, routes for traceability to the international standard for length, standardized tests for evaluation of sub-systems within the optical systems and draft standard guides for the application of electronic speckle interferometry, image correlation, geometric moiré, grating interferometry, photoelasticity and thermoelasticity.