In-plane strains measurement by using the electronic speckle pattern interferometry

Abstract

Two-dimensional in-plane displacements and strains are measured using an electronic speckle pattern interferometry (ESPI) system based on the dual beam speckle interferometric method. Different types of specimens are used: a flat plate, a cracked-plate, and plate with a central hole of 12 mm diameter. Two-dimensional fringes obtained from real-time images are analyzed by an image analyser. The values of in-plane strains obtained by the ESPI technique show high accuracy compared with those measured by strain gages.