Three-dimensional models help find potential conflicts and errors in design compared to traditional design and construction techniques using 2D plans and profiles. 3D models show a project in a digital form that can be analyzed to find inconsistencies that would not normally be discovered until the construction phase.
ODOT's technical bulletin RD13-03(B) provides clarification concerning the required content, process/workflows, delivery timelines, and quality control of digital 3D roadway design data for Oregon's Statewide Transportation Improvement Program projects. The technical bulletin does not require 3D renderings or simulations for any design contracts.
"3D, 4D and 5D Engineered Models for Construction," March 2013, is a technical brief published by the Federal Highway Administration that provides an overview of 3D modeling. It includes technology applications during design and construction, benefits to stakeholders, resource requirements, current state of practice, and advanced applications such as adding 4D and 5D components.