2017 Volume 73 Issue 2 Pages 133-149
A damage identification method for inner cracks of RC bridge deck was investigated. A local resonance of RC deck was excited by forced vibration test using a portable shaker, and local resonance frequencies could be measured. As the experimental results of the RC deck specimens, the local resonance frequencies were significantly decreased on the area including an inner void. Moreover, the damage estimating equation was proposed based on the linearity relation between the local resonance frequency and the void length.
The RC deck was removed from the highway road bridge, and the distributions of local resonance frequencies were measured. It was indicated that the local resonance frequencies were decreased on the areas including inner cracks. Moreover, as the experimental results of field test on the highway bridge, it was shown that the areas including inner cracks were fairly identified based on the decrease of local resonance frequencies obtained by the forced vibration test.
