Challenges of complex tunnel design
As a tunnel engineer, Mitchell focuses on complex tunnel design and analysis, including the creation of 3D and 2D tunnel models. While he finds the work is rewarding, he notes “the processes involved are often time-consuming and repetitive.”
One such process is validating the compliance of concrete linings in 3D tunnel models, particularly for complex shapes that cannot be analyzed using traditional 2D models. This includes areas like junctions, large caverns and unique structures where tunnel-boring machine (TBM) concrete segments interact in specific ways.
When asked about the most common challenges in complex tunnel design, Mitchell highlights three processes ideal for automation:
- Validating individual concrete thicknesses sequentially, one after another.
- Accounting for overlapping reinforcements and varying bar placements.
- Intuitively visualizing localized stress points and structural behavior.
Automating tunnel lining reinforcement design with VIKTOR AI in SAP2000 and Strand7
These challenges led Mitchell to automate the process by building a Python-based app on the VIKTOR AI platform. Because the calculations run as Python code, they are deterministic: the same inputs always give the same reinforcement design, so every result can be checked and repeated.
With VIKTOR AI in Strand7 and SAP2000, the automated process lets engineers:
- Import geometry and structural actions into the app
- Include torsional effects by using Wood Armer theory
- Visualise the reinforcement demand in 3D in real time
- Pre-define desired reinforcement patterns
- Automate and optimize reinforcement placement based on the predefined patterns
- Generate detailed visualizations and reports for quality assurance.
Because every run produces the same report, a checking engineer can review the reinforcement demand and placement for each lining section before the design is used.
“I wanted to make my job and my colleagues’ jobs easier while demonstrating the power of coding,” Mitchell explains. By using the application, engineers save time on repetitive tasks, allowing them to focus on more detailed analysis and other critical aspects of their projects.
Weeks saved on 2 major tunnel projects
So far, Jacobs engineers have used the app on two major projects: a tunnel system in the Middle East and a desalination plant tunnel in Western Australia.
On both projects, the automated process saved engineers weeks of time and helped teams:
- Quickly identify areas of the tunnel requiring additional reinforcement.
- Detect and correct modelling errors.
- Generate comprehensive validation reports.
- Reduce errors through robust quality assurance workflows.
Since the optimization works from predefined reinforcement patterns, engineers can compare layouts and pick the best one that meets the design checks.
By integrating the geometry, users can also immediately determine if the model behaves as expected. If it doesn’t, this indicates that the original FEM model needs to be revisited – something designers might otherwise only realise after hours of analysis.
It’s rewarding to see colleagues recognize how investing in automation can enhance our engineering processes.
Mitchell MacMahon
Jacobs Tunnel Engineer
How the process was automated, validated and scaled
Mitchell automated the tunnel design process by building an app on the VIKTOR AI platform. He connected his existing files with code to the backend “like Lego blocks”.
Before colleagues used it on projects, the automation was validated on the platform: it moves through a DTAP pipeline (Development, Testing, Acceptance, Production), so it is tested and approved before release. Role-based permissions control who can change it and who can run it, and version control and audit trails show which version produced which report. Because it runs on the platform rather than on Mitchell’s laptop, every colleague uses the same validated version of the app in the browser.
Inspiring colleagues to automate their own processes
For Mitchell, developing this application has been a great success both professionally and personally. “The app demonstrates how automation can reduce time-consuming tasks, increase accuracy, and inspire teams to think creatively about workflow improvements,” he says.
What’s next?
Do you recognize these challenges? Our team can help you analyze your engineering processes and identify which ones to automate with VIKTOR AI. Book a demo.
