Countermeasure of Air Venting Holes in the Bridge Deck–Wave Interaction under Solitary Waves

Abstract

This paper discusses three fundamental questions on the bridge deck-wave interaction: (1) are there countermeasures to mitigate the wave forces on the bridge decks? (2) what is the working mechanism of the countermeasures? and (3) what is the efficacy of such countermeasures? Motivated by these questions, a literature review is conducted and the air venting holes in the bridge deck slab is preliminarily identified to be a countermeasure for the bridge deck–wave interaction. To reach a deeper understanding of such a countermeasure, a solitary wave model is utilized here to carry on the numerical simulations. The shear stress transport (SST) k-ω model is considered as the turbulence closure for the Reynolds-averaged Navier–Stokes (RANS) equations to account for the turbulent bridge deck-wave interaction. Six different venting ratios for cases that the bottom of the bridge deck is at the still water level (SWL) are considered with detailed analysis of the characteristics of the air venting process, such as the pressure change in the chamber, the flow rate of the air and water through the air venting holes, and the force changes. Thereafter, different structure elevations, representing different submerging scenarios, with one target venting ratio are further studied. It is proven that this countermeasure is in favor of reducing the positive vertical (uplift) force substantially, but it results in an increase of the horizontal force correspondingly. This, in turn, requires more designing considerations for the supporting system to the bridge superstructures. This study will improve our understanding of this potential application in future engineering practices.