Computer Modeling and Analysis of Truck Generated Salt-Spray Transport Near Bridges

Large Eddy Simulation and Analysis of Truck Generated Droplet Spray Transport at Bridges

“…The FHWA has undertaken a multi-year project to update the 1989 TA to make it more quantitative in lieu of its current qualitative form. The CFD part of the project is covered in two reports [8] and this report. The CFD analysis models how vehicular tire spray can be transported from a roadway up to an overhead bridge structure using a model comprised of two rigid bodies (the bridge with surroundings and the vehicle) in a fluid domain, with the vehicle moving through the fluid domain at a specified speed.…”

“…The CFD analysis models how vehicular tire spray can be transported from a roadway up to an overhead bridge structure using a model comprised of two rigid bodies (the bridge with surroundings and the vehicle) in a fluid domain, with the vehicle moving through the fluid domain at a specified speed. The efficacy of this approach was first explored in 2011-2013, [8]. The current effort explores the effect of underclearance, girder spacing, girder height, deck overhang distance, and vehicle speed on the deposition of truck tire spray from wet roads on overhead bridge girders.…”

“…Based on the literature and previous work [8], droplets are injected from tire surfaces at a mass rate of 0.5 kg/s from each wheel at a spray angle of 7.5 degrees from the tangent line with the tire tread. Each injected and tracked droplet is referred to as a droplet parcel because it represents many droplets that follow the same statistical path.…”

“…The software tracks a maximum of about 300,000 droplet parcels efficiently, and that means that a droplet parcel represents about half a million droplets. The droplet spray coming off the truck tires has a size distribution, and previous work [8] has shown that spray droplets escaping the wheel well or mud flaps and undercarriage are in a size range of 0 to 100 μm because larger droplets have too much inertia to make the turn from wheel well or truck trailer under carriage out into the truck wake without hitting surfaces of the wheel well or under carriage. The droplet size range is divided into categories in Figure 3-3.…”

Probabilistic Prediction of Corrosion Damage of Steel Structures in the Vicinity of Roads

“…The spread of chlorides is significant especially on a local scale, near the vicinity of roads, depending on the parameters of the surrounding environment, the quantity and nature of barriers located in the vicinity of the road, speed and intensity of traffic, etc. [8][9][10]. Experimental measurements carried out at selected bridge structures and in their surroundings called attention to the fact that the quantity of deposited chloride ions spread in the air is also significantly impacted by the design of the bridge structure and the topography of the surrounding terrain [11][12][13].…”