Abstract:

The characteristic vectors and the sensitivity of the damaged reinforced concrete beam(RCB) were derived from the analysis of the bending damage behavior of RCB. The lending damage coefficients of the mid-span section rigidity were found most sensitive to the increment of vibration characteristic vectors of the damaged RCB, and they increase as the loads go up. The sweep cheek by the electromagnetic exciter and the theoretical study demonstrated that the basic frequencies of RCB after bending damage showed an obviously non-linear reduction with the load, and the tested basic frequencies of the specimen beam were obviously different from the theoretical results. The perturbation method can be used to correct the errors of the bending damaged RCB rigidity and to distinguish the bending damage degree of RCB.

Key words: engineering mechanics, bending damage, sweep check, perturbation, sensitivity