Title: Acoustic Transmission Technique for Evaluating Fatigue Damage in Concrete Bridge Deck Slabs

Author(s): Stephen D. Butt, Vidyadhar Limaye, Aftab A. Mufti, and Baidar Bakht

Publication: Structural Journal

Volume: 101

Issue: 1

Appears on pages(s): 3-10

Keywords: bridge deck; crack; fatigue; slab

DOI: 10.14359/12992

Date: 1/1/2004

Abstract:
The investigation focuses on the evaluation of a novel acoustic transmission technique (ATT) for tracking the fatigue-induced damage in a steel-free bridge deck slab under laboratory conditions. The technique comprises the identification of changes in acoustic waveform attenuation through concrete by comparing integrated waveform amplitudes recorded at two or more acoustic sensors. This methodology is based on the experimental observation that cracking in concrete leads to increases in attenuation of the acoustic signals. The mapping of cracks and other means of detecting damage induced by cracks were used to independently verify the conclusions from the ATT. Each of the four deck slab panels was subjected to approximately 1700 cycles of a heavy wheel load; the damage induced by this loading was tracked reliably by the ATT. The procedure of evaluating dimensionless integrated amplitude ratios rather than absolute signal magnitudes proved to be a highly robust and stable means of measuring attenuation, hence damage in the slab.