APPLICABILITY OF NONDESTRUCTIVE TEST USING REFLECTION WAVE FOR THE VOID-INVESTIGATION OF CONCRETE STRUCTURES

Abstract

The nondestructive tests for concrete structures have been conducted for the purpose of quality control and to estimate damages. However, there doesn't exist any precise standards for judgement and estimation of damages. Early establishment of nondestructive tests which are applicable for concrete structures is required from the point of view of the preventive maintenance. Therefore, the nondestructive tests using the impact elastic wave or the ultrasonic pulse wave were applied for the void investigation in concrete structures. Based on the results of tests in model slabs and in real concrete slabs of road structure and tunnel lining, it was confirmed that the nondestructive tests are applicable for the void investigation by observing the wave and analyzing the spectrum of dominant frequency.