Prediction of Adhesion Behavior of Sea-Salt Particles on Bridge Girders

Abstract

It is important to estimate corrosion environment of steel bridges for a proper corrosion prevention and maintenance program. The critical factors of corrosion are temperature, humidity and various dusts on the surfaces. Among them, the adhered sea-salt particulate matter (SSPM) is most important and therefore airborne SSPM near a bridge site must be considered in its design. To prevent degradation of protective paint, forced wash out of adhered SSPM has been tried in some bridges. In order to make a proper plan of wash out, it is better to know adhesion behaviors of SSPM to bridge girders, which in turn depend mainly on the amount of airborne sea salt particles and wind on a bridge site. The objective of this manuscript is to pursue numerical method to simulate the adhesion behavior of salt particles oriented from ocean. To this end, adhesion behaviors of salt particles on bridge girders are estimated using CFD analysis. By the use of these basic behaviors with other data such as wind velocity, amount of airborne SSPM, total amount of adhesion of sea salt particles are numerically predicted. The comparisons between the numerical and observed results showed that the numerical analysis can reproduce essential behaviors of airborne SSPM.