Anu Khetwal

Geotechnical and Tunnel Engineer

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

Absolutely fascinating. For me, tunnel design is like solving a puzzle where you get into details of the site investigation, interpret what lies underground, and eventually use it to have an efficient tunnel design. I find this remarkably interesting.

I enjoy sharing my experience with young professionals and it’s fascinating to see them getting excited about this field and eventually pursuing their career in this industry.

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

I am a geotechnical/ tunnel engineer for WSP. I am currently involved in the design of the Baltimore and Potomac tunnel project. My work extends from tunnel excavation support design, intersection analysis, ground settlement analysis, rock mass properties estimation, and baseline report preparation.

I started in this industry in 2011 as a design engineer for Lombardi Engineering Limited in India. I was involved in the design of various tunneling projects in the Himalayas, Beirut, Switzerland, and other parts of the world.

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

I did my undergraduate in civil engineering and my undergrad project was related to environmental engineering. At that time, I had not imagined myself in the tunneling industry. It just happened that I got a job at Lombardi Engineering Limited, and they designed tunnels and hydroelectric projects. That’s where I got initiated in the underground industry working on a massive railway tunnel project in the Himalayas in India. My initial knowledge of tunnel design concepts came from my supervisor at Lombardi, which fascinated me.

My inclination towards the field grew as I learned more. Eventually, Lombardi Engineering supported me to do a Masters in underground structures and rock engineering. At the same time, I got involved in the detailed design of various tunneling projects around the world. My master’s thesis was on determining the dynamic properties of rock mass. My master’s work set me on a trajectory that brought me to the U.S. to pursue PhD in underground construction.

I was extremely lucky to be around such great professionals who were at that time building the world’s longest railway tunnel (Gotthard rail tunnel) along with some of the most challenging tunnel projects in the world. Their guidance and constant encouragement have made me who I am today. It is an excellent industry to be in.

What professional achievements have defined you and made you proud?

I am extremely proud of my Ph.D. research work. My Ph.D. research focused on incorporating the interrelationships between different tunneling activities using the discrete event simulation (DES) method for utilization estimation of TBMs. I identified a critical question in civil engineering: the uncertainty in determining the interrelationship with the tunneling activities during construction that corresponds to the overall completion time and cost of a project. The CSM 2020 model I developed as part of the research shows that parameters that are considered trivial can have a great impact on a tunnel boring machine’s overall performance and, ultimately, the success of a tunneling project. The implementation of the CSM 2020 model can have a groundbreaking effect on the tunnel projects.

During my time at Lombardi, I designed a tunnel portal for a hydroelectric project in Beirut, which was challenging. The bedrock (limestone) was covered by a thin soil layer, typically less than 1 m. No laboratory tests or field tests were available for the evaluation of the geotechnical strength parameters of the soil layer. The tunnel was to be excavated using the tunnel boring machine and the road which was carrying the parts of the machine had to cross over the excavated tunnel portal. I designed the tunnel portal and performed slope stability in the area which I am very proud of.

I am also proud of playing a significant role in the design of the T-48 tunnel project which was around 7 mile long with a parallel escape tunnel, 2 adits, and 26 cross passages in the Himalayas, India. I designed the cast-in-place liner, performed intersection analysis, and was deeply involved in the design of a shear zone where a converging support system was defined to accommodate the squeezing ground condition. These experiences have defined me and helped me to be where I am.

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

I would like to answer this question in two parts as there are challenges we face in the industry and then there are challenges that I faced as a woman in the industry.

The tunnel projects pose challenges in terms of variable ground conditions, location and purpose, limitations in the resources that play a critical role in the decision-making process along with time and cost constraints. Limited availability of geotechnical investigation data as I experienced for the T-48 tunnel project with over 1000 m overburden in the Himalayas was very challenging. I learned that one must always weigh the risks of proposing the design as it is all based on the interpretation of the core logs that extend only a few hundred meters below the ground, which often requires experience along with a strong knowledge of the ground behavior.

Secondly, in India, there was always a hesitation to send women to the job sites. I was often deprived of this opportunity. The pretense of this is the protection of women but this in reality deprives women of gaining knowledge in the field and holds them back from developing solid engineering judgement. I got this opportunity only later in my career which has been a major gain in terms of looking at the greater picture and understanding the significance of design calculations as a whole.

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

All good things. I believe that WSP is constantly giving me challenging jobs and preparing me to handle big, complicated projects. I am currently involved in the design of the Baltimore & Potomac tunnel project and learning a lot from the team. I am really fortunate that way. Also, my Ph.D. research work was on predicting the performance of tunnel boring machine and identifying the bottlenecks that cause delays in the construction process. I believe that this research will really help the tunneling industry.

For the industry, urbanization has caused an ever-increasing demand to go underground. I see tremendous opportunity in this industry with many more exciting projects to come.

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

Get your hands dirty. Getting practical experience early on is very important as it refines your engineering judgment. Listen to the professionals and ask questions because this is how one learns.

What led you to join UCA?

UCA is a great organization to get connected with professionals in the tunneling industry. I joined UCA when I was in college and have gained a lot from getting the opportunities to go to conferences, attending lectures by professionals, and learning a lot about this industry overall.