Random decrement technique for effectively determining dynamic parameters of bridges
Natural frequencies and damping ratios are parameters that play a crucial role in the field of Structure Health Monitoring - SHM. Despite they are fundamental parameters of structures, the determination of these modal characteristics of a bridge faces difficulties. Currently in Viet Nam, the primary methods for determination of modal parameters of bridges are based on analysis of data acquired in its inoperative conditions. Those methods also require testing vehicles as input exciters that commonly stop traffic on the bridges. This paper presents Random Decrement Technique - RDT, a simple and efficient technique diminish these effects in data calculating to determine modal parameters of bridges, which only uses ambient excitation. The required dynamic characteristics are compared to results from FEM analysis that confirm the method reliability.
Received: June 25th, 2017; revised: August 24th, 2017; accepted: February 28th, 2018