Document Type : Research Paper


Civil Engineering Department, Collage of Engineering, University of Mosul, Mosul, Iraq


Nondestructive tests 'NDT' are increasingly becoming necessary tasks to develop accurate measurements without causing ‎‎any damage to the tested elements. The outcome of the NDT is vital to determining the safety and ‎‎reliability composition of materials. This study aims to investigate the dependability of nondestructive tests using Schmidt Hammer and Destructive Core Tests in a fire-damaged area. More than hundred stations were considered in the nondestructive inspection. Destructive core test results were used to assess the NDT results in burned concrete elements. The results of the comparison, clearly demonstrated the ability of both destructive and nondestructive ways to capture the strength reductions in fired elements. The NDT test provided an optimistic and higher strength prediction (higher 35-67%) as compared to destructive tests. Greater optimism NDT results were significantly associated with elements that have been highly damaged by fire and the strength predictions efficiency were between 60-67%. The results showed deviations in the mechanical properties of predicted burned concrete strength, by both on-destructive and nondestructive ways that required strength calibration to the nondestructive test to ensure more reliable assessment. A strength degradation formula is also suggested and is under review.


Main Subjects

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