By Andrew Poszich, Contributing Author
Transportation project requirements are constantly evolving as technology is pushing the limits of what the industry can achieve. As such, designers and industry professionals are in a constant succession to stay abreast of advancing standards.
While full 3D modeling files are often included as part of CADD delivery, it’s often their derivative, LandXML files, that become the deliverables of focus. These reduced alignment and surface files serve as the backbone for many critical field processes such as automated machine guidance (AMG) and inspection.
However, they omit many key elements of the design and create a missed opportunity when they are not used in conjunction with other 3D file formats.
Much of the issue is file incompatibility between the software used by the designers and the software and equipment being used by the contractor/field teams, but this will change as data interoperability becomes more common and formats such as IFC (industry foundation class) become solidified as the new standard. DOTs are also pushing the industry more towards a future that keeps the 3D model at the center of the design process.
This all culminates in a joint effort involving everyone in the transportation industry moving to make communicating designs easier and more direct.
The Need for More Detail, Communication
The last several years have seen a major shift from 3D modeling being a nice-to-have, cross section generator to being a critical component in any design workflow. With the industry seeing a major push for 3D components such as drainage, structures, geotechnical and utilities, as well as building information modeling (BIM) becoming more mainstream, it is critical to look beyond standard requirements and begin identifying tools to optimize the design and construction processes.
Underlining all the other benefits of 3D design is the premise of improved communication. Design updates can be seen in real-time, geometry checks between disciplines happen passively, and design interpretation is kept to a minimum.
That being said, the 3D model is only as powerful as its weakest component. Missing components can create a greater expense to the project than the actual effort it would take to bring these elements into the 3D design. Teams proficient in these comprehensive workflows where everyone is contributing to the federated model consistently outperform those that rely solely on a 3D specialist.
Once a team agrees on developing a complete 3D model, the door is opened to further leverage the model as a communication tool. With all components properly represented, engineered visualization can easily be introduced to bring greater context into meetings, to measure performance more easily, and to expedite decision making.
This ability provides clients, business partners, and, in some cases, the public with a clearer understanding of the project and will quickly become an integral part of any team’s workflow.
While the benefits are vast, it’s important to remember that reliance on the model does not replace proper communication. The project team must leverage the toolset given while continuing with standard best-practices. There is also no shortcut for teams to learn how to best utilize the 3D workflow. It takes time.
3D Workflow Benefits
Think about the traditional 2D workflow our industry has followed for decades at this point. We have kickoff and status meetings and email threads. We catch up on projects via word of mouth, and we might not see the latest updates until we see the latest PDF prints.
In a 3D workflow, BIM data replaces PDFs, and file updates now include dynamic design that can be seen in real time. The benefits of 2D CADD workflows quite literally have an extra dimension to them with the potential to include additional information, such as cost and schedule (4D and 5D modeling). The 2D conflict container files now can have that additional level of detail, replaced by their federated 3D counterpart.
A traditional quality control workflow is a very iterative workflow process – a designer designs something, then someone puts that into a plan set, labels it, prints it to a PDF, and then someone else reviews it, marks it up and puts it back into the system, only for the process to start again after the comment has been incorporated.
The use of current technology ushers in new collaborative elements that increase project efficiency and safety. Design criteria confirmations, safety analysis, geometric clashes and design changes and updates can all be performed in real time. The model becomes your single source of truth for all design components.
With the opportunity for both passive and active quality control, designing in 3D allows for issues to be identified sooner simply through an awareness of surrounding components. If someone wants to review the design, there is no wait. If teams design with a 3D-first mentality, items can be reviewed immediately, reducing the amount of project delays.
Imagine a comprehensive clash analysis without the inclusion of bridge foundations and underground utilities, or perhaps setting guide sign foundations without being able to visualize off-site grading. This is still business as usual for many in our industry, but for those who have invested the time into mastering our 3D capabilities, these are invaluable processes that are a must-have on any future project.
Once all disciplines are using this process, you get a conflict review benefit where lighting signals, drainage, ITS and more are in their real spaces in front of you.
Evolution of 3D Modeling
The genesis of 3D modeling in the transportation market grew out of a means to an end. What started with cross sections on plans soon evolved to benefitting quantities to show more accurate earthwork and component analysis.
Construction assistance with AMG created a reduction in errors and omissions, and now incorporating BIM creates data-rich 3D models that have spawned the project lifecycle revolution. As everything in the model overlays, the data we use has more longevity that can carry on through to construction.
Progressing beyond just the roadway, designers can use 3D modeling to dynamically profile ditches or design utilities and more quickly uncover any structural conflicts. Templates can be made that will give warning messages when a designer is out of design tolerance. Most obviously, you can see when something is wrong because it will be geometrically misaligned in the 3D model.
The surveying process becomes more integrated with 3D design, as their work is 3D by nature. Using enhanced tools and techniques, underground utilities can be mapped in 3D, geotechnical analysis can be brought straight to the design software, and point clouds and reality meshes can be leveraged to truly model structural components as CADD files become more data powered. Much of this information was already being collected, but now it’s much easier to access!
Now we can model bridges and link them to roadway alignment and superelevation while analyzing the columns, footers, and piles immediately. As a result, the model can provide enhanced context for other teams via underground clash detection, overhead utility considerations, excavation limits, and even sightline analysis.
Adoption Takes All of Us
As technology progresses, we are oftentimes left to learn new tools and software. OpenRoads Designer and Civil 3D are design applications utilized by the AEC industry that have both seen major overhauls in recent years geared towards the development of digital delivery workflows. Many state DOTs are already using these 3D-centric applications in some capacity; in fact, some are already signing and sealing models without paper plans, truly embracing digital workflows.
But this shift toward 3D design goes beyond any one application. The reality is that it takes many moving parts to make purely digital workflow efficient. Those that have successfully crossed the digital delivery barrier are seeing great returns on construction savings and risk mitigation.
Through this, we’re adopting new ways of doing work and doing business. We’re fully reviewing and letting a project without relying on paper plans. We’re leveraging BIM for infrastructure, which has intelligence built into models and design to revolutionize the way we do business. We’re even using game engines to bring our designs to life in a realistic and life-sized way.
The 3D design workflow model creates the opportunity to break down walls across an organization and open project teams to an entire company or agency, in turn creating the opportunity to tap into more resources.
As a result, we can design and complete more accurate projects in less time with better, more effective collaboration. This workflow is a win-win for our industry and our clients.
It’s a win-win that should be realized across our industry sooner rather than later.
Andrew Poszich has been with RS&H since 2014 and has a master’s in civil engineering from West Virginia University.
