At present, the core test is commonly employed for testing the properties of aging concrete structures. This test, which requires coring concrete samples for subsequent offsite laboratory testing, is somewhat destructive and limited to taking samples from only a few locations. This paper reports an optical technique based on shearography for nondestructive testing of concrete properties. The technique does not require coring and therefore allows testing on many structural locations to be performed. The preliminary results have demonstrated that the technique has great potential for development into a practical tool for testing of concrete modulus of elasticity and concrete strength.
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