Vojtech Gall

Senior Tunnel Engineer
Gall Zeidler Consultants

What do you do in the underground construction industry, and how long have you been in the industry?

I am a senior geotechnical engineer at Gall Zeidler Consultants. Because we are a specialty consulting firm, I am involved in several national as well as international tunneling projects. My duties range from design work to construction support along with a bit of project management. Lately I’ve also been involved in some business development in Canada. In addition, because of my academic background, I often get called in to deal with specialty or niche issues, like how to best consider long-term swelling in rocks, which is something I am looking into now.


How did you get into the industry, and why did you decide to pursue it as a career?

As my name suggests, the path to tunneling was quite easy for me, as I joined the family company! Even so, I wasn’t sure that I wanted to become a tunneler from the start. I originally studied physics (which was a bit too theoretical) and then switched to a Master’s in Geotech before getting a Ph.D. in Structural Engineering. My Ph.D. program had around 30 researchers all working in different tunneling topics, and this breadth of research and potential in the field is what really pushed me to go into it.


What is it like to work as an engineer on underground projects?

The one thing that all projects have in common is that, because of each tunnel’s unique geology, there is always some unique challenge where you have to learn something new to be able to address it. That being said, the type of work you do really depends on the role that you have in a project. Sometimes independent design verification (IDV) can be really enjoyable, because there is a bit less risk than if you are the lead designer. On the other hand, sometimes as an IDV you get a bit sidelined if things get tight. Similarly, being the tunneling lead can be really rewarding because what you design gets built, but there is definitely more stress and responsibility involved.


What professional achievements have defined you and made you proud?

Off the top of my head, I would have to start with my doctorate, because I spent six years doing it! I did it internationally, in Germany, and had to adapt to a different system than we have here in the States. Plus, I got to know some really great people, many of whom I have been able to continue working with even now that I have “switched” continents. One of them even works for GZ now, and I am very proud to have brought him along. In that sense, the doctorate was more of a personal achievement than a technical one.


On the technical side of things, I just led a team that developed a TBM breakout design. The whole thing, i.e., the cut, is reinforced only with dowels and the segments, which include hybrid steel-fiber and traditional rebar reinforcement. I’m pretty proud of how that came together.


What are some of the biggest challenges you have faced, and how have they been meaningful?

When I started work at GZ, the first task I had was to evaluate rockburst potential within a deep hydropower cavern in the Andes. It took a while, but my team and I put our heads down, read through the literature and project records, and eventually came up with a technique that worked within the project constraints. The whole experience taught me to not worry if there is no immediate solution to a problem, and that with a bit of hard work, a solution will eventually come. On a second, more down-to-earth note, I also learned that sometimes you get lucky and deadlines get extended!


What do you hope the future holds for yourself and for the industry?

I hope that we build more tunnels here in the United States! I hope they become more of a first choice than a last resort as they sometimes are. I also hope that our industry becomes a bit greener. I recently learned that concrete production (due to clinker production) accounts for around 10 percent of the world’s carbon dioxide emissions, which is a very high number. In that sense, I hope we start using concrete mixes or concrete alternatives that have a smaller carbon footprint. After all, it takes quite a bit of concrete to build a tunnel.


What is your advice to a student looking to enter the underground field?

(1) Get some on-site experience early on, and (2) Do all the learning you can take before joining the workforce, because you won’t get a chance to re-learn the basics on the job. Tunneling is quite interdisciplinary, so it is very difficult to separate geotechnical problems from structural problems. Having a good background in both is very helpful.