The impact echo method has been widely used to evaluate the integrity of concrete
structures. This paper is to study damage detection technique of concrete members using impact
echo method, one of the nondestructive tests based on stress waves. Stress wave propagation
behavior is to be studied based on wave mechanics in concrete media. Based on the theoretical
study, nondestructive tests using stress waves will be conducted to observe the wave behavior on
structural damages. For the damage detection of concrete structures, a mock-up specimen was
prepared, and various tests were conducted for the study of the behavior of stress waves. The
concrete slab of the flaw detection consist of 5 types; the first group for the thickness presumption,
the second group for the position of the voids, the third group for the position of the re-bars, the
fourth group for the position conduit, and the fifth group for the position of the crack. Test results
are evaluated and summarized to verify if the nondestructive tests can survey damages in the
concrete structures in this paper.
Damage detection in concrete structures using tunable piezoelectric actuators