Nondestructive Testing Methods for Evaluating Damage and Repair of Concrete Exposed to Fire
Richard A. Muenow and Melvin S. Abrams
Appears on pages(s):
bond (concrete to reinforcement); concretes; damage;
evaluation; fires; impact hammer tests; nondestructive tests;
repairs; ultrasonic tests
Evaluation of fire-damaged concrete has been made using field-applicable test techniques which are valuable but limited. With the advent of reliable non-destructive testing methods, a much more comprehensive assessment of damage is available. The objective of this paper is to present. information on Pulse-Echo, magnetic and microwave testing techniques. Pulse-Echo non-destructive testing can be conducted on insitu concrete for: measuring thickness of damaged concrete assessing bond loss between concrete and reinforcing steel detecting internal cracks and their orientation determining degree and extent of cement matrix microcracking estimating insitu concrete compressive strength Accompanying the Pulse-Echo method are steel reinforcement location techniques that involve microwave and magnetic principles. These tests can determine remaining concrete cover and additional data for engineering the required repairs. Of equal importance to the assessment of damage is the evaluation of the performed repairs to determine that the repairs satisfy all the structural requirements of the original specifications.