• CHI Consulting Engineers

Numerical Evaluation of Vortex-Induced Vibration of Bridges with Painting Containment Systems

There have been many incidents of large vibration of long span bridges with painting containment systems due to the change of aerodynamic characteristics of the bridge cross section and consequent vortex shedding, i.e., VIV, even at low wind speeds. VIV might compromise the useability of the bridge, leading to interruptions in the bridge operation and anxiety among the bridge owner and public, and in some cases pose significant risks to the safety of structure.

The traditional method of addressing the VIV risk is to perform wind tunnel tests. However, wind tunnel tests can be expensive and time consuming. To supplement the wind tunnel testing, CHI implemented a numerical evaluation approach to provide a faster evaluation of VIV risks: a Computation Fluid Dynamic (CFD) analysis is first carried out to calculate the dynamic wind loads from the vortex shedding at a long span truss bridge with painting containment systems; then a transient finite element (FE) analysis is performed to determine the peak displacements and forces in the bridge structure under the dynamic wind loads.

Based on our analysis, it is believed that the numerical evaluation by the combination of CFD and FE analysis is a feasible approach to assess the risks of VIV. Final confirmation of VIV may be conducted by the wind tunnel testing if the risks are deemed sufficiently high.