Designing Ahead of the Curve…

July 12, 2018

One of the challenges with the construction of wind farms is the transportation of wind turbines (WT) and their components to the site. The custom, oversized vehicles that are needed to transport the WTs have issues at intersections that were designed for conventional automobiles and commercial motor vehicles. Horizontal curves on public roadways with a standard design radius often need additional widening to allow the passage of the trucks transporting WT components. 

One tool that Fisher uses to evaluate intersections along the route to be used to transport WTs is AutoTurn®. 

AutoTurn® is an advanced, interactive software program that provides 2D and 3D models of clearance envelopes for transportation vehicles. It includes all of the AASHTO standard vehicles and has a library of hundreds of additional vehicles. There is also an option to modify or create virtually any vehicle. The 2D models for custom oversized vehicles are used for intersection assessments and allow an engineer to analyze the intersections, roundabouts, parking lots and staging areas to determine if any improvements need to be implemented prior to delivery. During the assessment, there are many variables that need to be assessed including the angle between the entry and exit tangent of the bend, the bend radius, the specs of the transport vehicle and the use of rear steering wheels that are controlled independently. The model helps engineers determine the exact highway improvements needed and assist in preparing the Highway Work Permits at intersections that may need improvements. This data can also be used to determine the sizing of the staging areas to more accurately allow for better traffic flow of delivery vehicles. The 3D models are used for engineers to analyze the areas for vertical clearance issues such as railroad, culvert or pipeline crossings. 

Detailed models can help reduce existing conflicts during the construction delivery phase and minimize surprises during transport.