A study of the impact damages detection and dynamic responses of RC bridge piers based on a frequency domain correlation method

Abstract

The applicability potential of correlation methods (damage correlation indexes) based on frequency domains in the impact damage detection fields of reinforced concrete columns were examined in the present study. In the current study’s experiments, four reinforced concrete bridge pier members of reduced scale were impacted by a new type of ultra-high drop hammer experiment system in order to simulate the processes of medium-sized trucks impacting bridge piers. The frequency response functions of the members before and after damages occurred were measured using an acceleration acquisition system. The experimental results revealed that the damage correlation indexes (DCI) taken into account the multi-order modal frequencies could be used to accurately identify the degrees of damage to the piers. In addition, an impact finite element model and a modal analysis method were matched with the experiments and were established using the commercial program LS-DYNA. Finally, the setting of the finite element parameters matching the experimental results was applied for the purpose of simulating the impact processes between the medium-sized trucks and the reinforced concrete piers. In order to meet the structural design requirements, a peak impact force (PIF) formula under vehicle impact conditions was proposed based on the damage indexes.