UDOT’s intelligent design effort includes moving to an all 3D work flow – a revolutionary change in the way state departments of transportation do business.
UDOT is leading the nation in important innovations which will save time, reduce mistakes, and conserve public funding.
3-D models allow every aspect of a road construction project to be viewed from any angle. State DOTs produce 3D design models that are then converted to 2D paper plan-sets to be advertised and delivered to the construction contractor. Plan sets are stacks of paper diagrams that illustrate each aspect of the project, such as pavement layers, drainage structures like pipes and culverts, underground geotechnical features, etc. The plan set production process is 60 to 70 percent of a UDOT designer’s time during pre-construction.
Often, contractors need to re-create a 3D model to build the project. By providing the contractor with a 3D model instead, UDOT will save an estimated 60,000 hours a year, the contractor won’t need to re-create the 3D model, and bid prices will likely be lower.
Other advantages of an all 3D workflow include
- A more accurate view of project features
- A more efficient use of technology during construction
- Better communication between designers and contractors
- Greater accuracy estimating quantities of materials for building the roadway
- Elimination and mitigation of errors during design and construction
- A higher-quality construction product
Automated Machine Guidance on I-80 shows important benefits
Automated Machine Guidance (AMG) allows contractors to use 3D models to program heavy equipment, like excavators and pavers, to work automatically. Most contractors use AMG.
UDOT recently realized some important benefits by providing the 3D model to the contractor on the I-80 Silver Creek to Wanship paving project. Coring tests after paving showed two deficient pavement cores versus eight deficient cores compared to non-AMG pavement. AMG also resulted in fewer ‘must-grind’ corrections. These advantages add up to longer pavement life.
In 2016, Region Two will advertise the I-215 resurfacing project using the 3D model for information only. Providing this model will save the contractor from having to create a 3D model from scratch, may allow for better bid pricing, provide the construction crews with the ability to check final grade with a GPS unit, and help locate underground utilities.
Eventually, UDOT would like the contractor to return post-construction 3D ‘as-built’ files which show how the project was ultimately built. With 3D files in hand, UDOT designers will have a much easier task when future work is necessary.