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2. ASTM-C1383-15, Standard Test Method for Measuring the P-Wave Speed and the Thickness of Concrete Plates Using the Impact-Echo Method, ASTM International, West Conshohocken, PA, 2015, www.astm.org, 2015.
3. ASTM-C1740-16, Standard practice for evaluating the condition of concrete plates using the impulse-response method, ASTM International, West Conshohocken, PA, 2016, www.astm.org, 2016.
4. ASTM-D6432-11, Standard Guide for Using the Surface Ground Penetrating Radar Method for Subsurface Investigation, ASTM International, West Conshohocken, PA, 2011, www.astm.org, 2011.
5. Imaging concrete structures using air-coupled impact-echo;Zhu;J. Eng. Mech.,2007