UDOT is moving to an all-3D environment which includes greater use of available design capabilities and an eventual move to a full 3D project workflow.
A photo-realistic image: UDOT built a new bridge over the Virgin River on S.R. 9 near Hurricane to accommodate increased traffic volume. This rendered image shows the new bridge superimposed over the existing bridge, which remains in use.
Embracing a 3D workflow environment will produce some important advantages, including the use of models that can be viewed from all angles in order to assess constructability, utility clash detection models that show a full representation of underground utilities, and animations that can show the built project along with expected traffic flow.
3D models, animations and illustrations can help bridge the communication gaps that sometimes occur among specialties at UDOT, or between the agency and stakeholder groups, since complex engineering data is more easily understood when presented in 3D.
For UDOT designers, the move to 3D represents “a fine tuning of the way we design,” says Bob Peterson, UDOT Methods Engineer. “We’ll be taking our 3D design to a full completion instead of just doing a paper copy as the final output.”
A full 3D workflow
Moving to a full 3D workflow means that projects will be modeled and provided to contractors as a 3D engineered model at advertising, and contractors will return an as-built 3D model that accurately represents project outcome.
Designers at UDOT have been working in 3D for about 20 years. Currently, when projects are advertised, 2D plan sets are made available to all bidding contractors. During the advertising time frame, contractors take those 2D sets and may create their own 3D model. Once the project is awarded, the winning contractor will typically finish a 3D model or hand-enter information for Automated Machine Guidance.
Getting as-built 3D models will represent a big efficiency boost to UDOT. “Once we get to the point where we know exactly what the existing condition is, then the designers don’t have to start from scratch anymore,” explains George Lukes, Standards Design Engineer.
Challenges and strengths
Lukes is overseeing the effort to move to a full 3D workflow. He sees challenges ahead, but recognizes that UDOT has some advantages as an agency, including working with a willing and capable consulting and contracting community.
“The big deal is advertising the project with the model as the legal document,” says Lukes. “Right now the legal documents are our plan sheets, the paper copies – legally that’s what the contractor has to follow. It’s a huge challenge to give the model to the contractor and say ‘this now is the legal document,’ but I think our contractors and consultants are very willing to sit down and figure a way to make that work.”
UDOT Region Four will take on the initial challenge of delivering a 3D model as an advertising package for three projects. All three projects will use CMGC, an innovative contracting method that allows close collaboration between UDOT and a contractor in the preconstruction phase.
Collaboration with the contractor during design will help UDOT minimize risks encountered when building the project “because they know the construction risks better than we do,” says Lukes. “It’s going to give us information that we need, the contractor will be on board with us while we do it, and hopefully we’ll get a lot of good lessons learned from that too.”
Fully embracing 3D capabilities will produce comprehensive planning, construction and design solutions that will benefit UDOT and all contract partners and road users. UDOT will learn how to better minimize risk. Bidding contractors will realize a big efficiency by not having to create baseline models from scratch. The winning contractor will also have UDOT’s model to modify for construction and 3D as-builts will make subsequent design processes more efficient. The outcome will be better roads and a more efficient use of transportation funding.
For more:
See FAQs with a timeline for implementing 3D, presentations, and more at udot.utah.gov/go/3-d
Bentley software training for UDOT employees is offered regularly. For more information, contact Bob Peterson at 801-965-4041 or bobpeterson@utah.gov
Also check out this flyer.