Mid-high frequency vibration attenuation properties of periodic U-rib plates: Numerical modeling and scale specimen testing

Abstract

Periodic U-rib plates are applied widely in steel box girders because of their light weight and high strength, but their associated vibration response and noise pollution are significant. The widely used statistical energy analysis (SEA) is an effective method to calculate structural vibrations at mid-high frequencies, but this approach does not consider indirect coupling mechanisms, which lead to errors. In this paper, the advanced statistical energy analysis (ASEA) approach is introduced to reduce vibration prediction errors in periodic U-rib plates for the first time. A scale U-rib plate dynamic test includes modal tests and the difference of energy level (DEL), which verifies the accuracy of finite element (FE) calculations. Thus, the ASEA algorithm was verified to be more accurate than the SEA and is used to calculate vibrations for actual U-rib plates. The results show that the ASEA is more accurate than the SEA mainly because it considers indirect coupling between non-adjacent sub-systems. The results calculated from the SEA have low errors within 5 dB when the distance between the sub-system and source sub-system is smaller than three times the U-rib distance. For larger frequencies, the energy discrepancy increases gradually from 100 to 2000 Hz, and the bending wave passes through each U-rib, which causes a 1.0–22.6 dB energy discrepancy. The influences of the rib shape and plate thickness are studied, and some suggestions are given.