08 - Kiran Mohanraj

Featuring Dr. Kiran Mohanraj, a serendipitous sustainability pal made by chance on a flight.

He is a pavement engineer who breaks down myths about zero-emission vehicles, pavement-vehicle interaction, and what true sustainability really means—plus drops some solid dad jokes along the way. 

Connect with Kiran on LinkedIn.

Terms mentioned:

• Heat Island Effect

Resources:

• Energy and Civilization: A History by Vaclav Smil
• APLCA and the LCA Certified Professional

Transcript

[00:00:00] Aparna: Welcome back, friends of the Pod. Today we have Dr. Kiran Mohanraj with us. He's a pavement engineer and project manager at the TransTec  Group in Texas. He has over 17 years of experience with pavement materials, testing, design, and construction, and received his master's in civil engineering from Arizona State University and PhD from the University of Texas at Austin. Hook 'em!

His current interests include design, construction, maintenance of sustainable and resilient pavements, behavior of asphalt binders in cracking and flexible pavements, an impact of pavements on vehicle fuel consumption, and their impacts to the environment. The two of us crossed paths on a Southwest flight from Austin to DC and I'm thrilled that the open seating plan ended up in us chatting for a few hours about our fields and eventually ended up in Kiran agreeing to be a guest on our show.

Kiran, welcome. We are so happy to have you here!

[00:00:51] Kiran: Thank you very much. I'm super excited to be here. 

[00:00:54] Aparna: We'd love to hear about your journey to being a pavement specialist at the TransTech Group. So can you tell us more about how you got here, the steps you took along the way? 

[00:01:03] Kiran: Absolutely. Yeah, it'll be a pleasure to do so. I graduated with a degree in civil engineering in India and I stayed for my master’s and at Arizona State University, I met my advisor, Dr. Kamil Kaloush, and through him I got an opportunity to work at the National Center of Excellence on Smart Innovations at ASU. This is while getting my master's, I was working with him and the task that I was assigned was to develop some simple tests that would measure the thermal properties of materials that's used in pavements such as your asphalt and concrete and the composites of asphalt and concrete, and I was, not very sure why am I doing this? Well, I mean, it's paying tuition. I'll do it. I started looking into it and did more research and then also did more research on the surface properties of the pavements, like the texture, the solar reflectance. Eventually I took a class which was taught by three professors. One from the Department of Civil Engineering, one from Department of Mechanical Engineering, and another was a sustainability engineer. That's where all these things all tied together and impact what you call an urban heat island, which is very pronounced in places like Phoenix, which is where the university was. How does it overall impact sustainability? This was my experience at Arizona State, and right after that I graduated and I went ahead and started working as a materials engineer, specializing in paving materials. I worked for a couple of companies and after doing that for a while, I figured, "okay, I need to get back to the roots of pavement engineering" and I ended up at TransTec Group as a pavement specialist here. So the interesting thing about what I do at TransTec is, other than providing pavement solutions to several clients, I also get to work on some fun research projects where you study the impact of your pavement condition on fuel consumption of vehicle, and how this impacts people, profit, and the planet. 

[00:03:03] Kiersten: I would love to hear a little bit more about the fuel efficiency tie-in, but first, not all of our listeners may know what the urban Heat Island effect is, so could you define that for them?

[00:03:13] Kiran: Absolutely. Yeah. So the Urban Heat island is as the name sounds, it's a heat island that is created in your built environment. This can be because of how the materials in the built environment absorb the heat that is generated from the sun. And once they absorb it during the day, they're getting heated up and at night they start letting out heat. So, when you think that the sun has now set that the environment should cool off, it doesn't happen because, your surroundings are now artificially generating heat and making the atmosphere hotter around you. 

[00:03:48] Kiersten: Thank you. I t came up in my college studies as well more about tree impact and how having vegetation in urban spaces can help combat the heat island effect. Thank you so much for defining exactly what it is. If you could also talk a little bit more about what you spent your PhD at UT doing?

[00:04:07] Kiran: Sure. My PhD was actually, it didn't have to do with sustainability but the PhD work was looking at, cracking and asphalt pavements, specifically the asphalt binder that is used in your asphalt pavements and asphalt mixtures and, looking at the cracking properties under a microscope. This was basically a result of COVID when everybody went home. I went home with a microscope from the university, while I was working this is, and uh, at home I put together a setup that can look at cracking asphalt binders under a microscope in a micro scale. So if you were to really tie this all to sustainability, if you will have less cracking, you are not fixing the road as many times. Which means you're leading to fewer emissions that is caused, due to construction and the delay in traffic due to construction.

[00:04:57] Aparna: Build it once and build it right. Build it with some resilience from the get go, and you have to worry less about it as time goes on. Could you expand on the fuel consumption piece that you mentioned earlier, the current research that you're able to do with TransTec?

[00:05:11] Kiran: That's That's a wonderful question. I was hoping we'd get to that sooner than later. So this is another thing that I makes me a very interesting person when I go to a party. When they ask me, what do you do? And I have a few things that I can bring up to make it a nice conversation. As soon as I mention, do you know the road that you traveled on today could have consumed less fuel? You could have been spending less money on the fuel that has been consumed by your vehicle or polluting your environment through emissions? So the pavement has surface characteristics and structural characteristics, both of which can impact a vehicle's fuel consumption, whether it be a passenger car or a heavy truck. There's a range of traffic. The way this happens is when you're take into the surface characteristics, there two surface characteristics that actually contribute to excess fuel consumption in a vehicle. The first one being roughness. Now roughness is not how it feels when you touch it, but it's actually how bouncy is your vehicle as you're traveling. If your vehicle is really bouncy, then there is energy lost in your suspensions of your vehicle, and when there's energy lost, you have to compensate by consuming more fuel. So that is one aspect where you're looking at your pavement surface characteristics and your roughness characteristics There's another pavement surface characteristics called the texture, or the macro texture to be more precise about it. This is how you would feel when you touch it. When your pavement has texture, that means your tires dig into it a little more. Then when your tire bounces back, your tire is also viscoelastic as you would, call it when it bounces back, there is energy lost due to hysteresis and when this energy is lost, your tires end up consuming more fuel and therefore you will, when you go tire shopping, there are fuel efficient tires. These are the two surface characteristics that can impact your vehicle fuel consumption. And the third one is your structural characteristics, which basically tells you how durable and how strong is your pavement. If you place a heavy load on it, is it going to deflect much? And if it does deflect it creates a superficial slope, an imaginary slope that your vehicle has to climb which would end up consuming more fuel. Just think of it when, and this is, this is what I talked to when when I give my presentations on pavement vehicle interaction and the fuel consumption due to pavement vehicle interactions, I talk about this: when my son was born, he started rolling over, and he was very easily able to do it on the floor. and my wife came and called me and she said, "look, he's rolling over!" and then my excitement was subdued by experimentation. I pick him up, I put him on a mattress and then watched him go, “EEEE” and he wasn't able to roll over. Well, I guess I slept on the floor that day. But, rolling resistance, that, basically is the example of how your pavement, structural characteristics play a role in excess fuel consumption or energy consumption. 

[00:08:03] Kiersten: That is fascinating. I, I love discovering new ways that sustainability exists in the world and I have to say this is a first. [Haha] I've never heard about the relationship between the performance of your tires and the friction and the fuel efficiency. So question, to you then: Are potholes good or bad in this scenario from a sustainability perspective? 

[00:08:27] Kiran: So there's actually an anecdotal joke about this. When we talk about potholes and it rains, it creates little bird baths, and now birds can swim in it, right? So is that sustainable or not? However, from a pavement engineering perspective. Potholes are never good. I mean, if there is a pothole, it has gone too far. Definitely potholes do create a bump and that bump will cause your vehicle dynamics to consume more fuel. Now, not only does it impact your vehicle fuel consumption, but if you think about it, if your vehicle moves a lot, then it will also cause an opportunity for it to go into your repair shop. 'Cause you might damage parts of your vehicle, which is also not good because you end up consuming more carbon trying to repair that vehicle, right? Or energy, trying to repair that vehicle. And ultimately, as a pavement engineer, I have to say, I don't like potholes on my pavement. It not only is bad, but it also, accelerates the deterioration of your pavement. 

[00:09:21] Kiersten: So potholes stink in many different ways is what I'm hearing here. 

Thank you so much for that explanation. I'd love to hear if there are any emerging trends that you're tracking in pavement engineering.

[00:09:33] Kiran: Yes, absolutely. I think emerging trends in engineering tend to align with each other. The kind of trend that we are seeing in pavement engineering, include what you're seeing in terms of, you know, data science, artificial intelligence and sustainability, or, rather putting it in a different way, enhancing performance responsibly. There's another way of looking at sustainability here. So if I were to talk about some of the trends that might really be exciting and to look forward to, is going to be the big data that has come in where you can see giant, giant amounts of data being collected and using those to, perform analysis and understand, performance of infrastructure better. There's also digital twinning. But again, going back to the data science and the big data is where I would, be very, extremely excited about this. This brings the point about advancement of technology because technology has come quite far. So, the way I look at it is that you have plenty of data now, but also your technology has advanced so that you can really start digging up old research, which could have been shut down or shelved because the technology that it was dependent on was not advanced enough and, and you were not able to, go forward because you didn't have the right tools. But today, you know, the technology has advanced and you have the tools. You've stored all that old research. You can bring it back. You can take it up again. Grad students, if you're listening - and you simply, try it with newer technology and you can find newer results. And when you have a lot of data, you know, three, three decades ago we couldn't do and now when you start looking at data collection, you can start with data collection. And we have technology that's advanced enough to store all this data because these are some of the challenges in the industry that you come across. Is that, okay, can I collect this huge amount of data, and if I do, then can I store it? And once you've stored it, you have to process it, right? I mean, when you collect large amounts of data, it collects a lot of noise too. So you need the tools to be able to filter through this noise and basically your data processing before you can interpret the results. So we have actually come forward, and advanced in technology, and data sciences to be able to do, a lot of research that were shelved in the past. This is what really excites me a lot.

[00:11:52] Aparna: Really cool application of data. I feel like we hear about it in a lot of different realms. I haven't heard it as much with the transportation space yet, so it's really fascinating to see how integrated it's becoming as time goes on. 

[00:12:04] Kiersten: Kiran, I can't say that I've ever met anyone with your job title before. And our show is about explaining what people do and what job titles mean at different companies. So could you just tell us a little bit about what a day in the life looks like? 

[00:12:17] Kiran: Sure. Yes. So a day in the life of a pavement engineer is more interesting than you would think it is, because I never dreamt of being a pavement engineer. When I was a child, I just wanted to be an engineer and build stuff. The way I explain this to my children when I'm driving to school is they talk to me and I ask them what they're gonna do in school and they ask me what I'm gonna do at work. So it's a quid pro quo there, right? So, essentially the way I would explain this to my children is go and fix all the roads here in Austin, Texas. So that is one thing. I do fix all the roads, however that fixing it goes anywhere from designing a new pavement by taking into account the local climate, the local traffic, and the locally available materials, or going and rehabilitating an existing pavement. Once again, considering all these things, taking all these things into account, and look at maintaining the existing pavements, so these are the things that a pavement engineer would do.

Now, this is in broad strokes. Like any specializations within these, you have sub-specializations. And the things I do here around is mainly designing newer pavements and rehabilitating them, finding innovative solutions, by using locally available materials and trying to be responsible in the way you design and construct pavements. 

[00:13:39] Aparna: Lots of different facets for you to, you know, explore your curiosities, really share out learnings and just be creative. So It sounds like a very fun job that you've landed for yourself. Also on the job, I'm wondering if there are any misconceptions about your role, about how sustainability integrates into what you do on a day-to-day that you'd like to address here? 

[00:14:00] Kiran: I definitely would like to do that as an avid listener of the podcast. I think it was Sophie Martin in episode three who mentions that she doesn't have the word sustainability related or associated with her title, so I don't have that either; in the industry, as any industry, and if you are working on space associated with sustainability, the, there are several misconceptions, a few of them that need to be clarified or at least understood.

And I realized these as I would talk to my parents, or my children, or my wife, or my friends at a party. So the first and foremost thing, which I really love about my industry is they defined sustainability itself, I mean. If you don't know it, if you don't understand it, if you cannot measure it. You cannot manage it. I mean, these are all the adages that go on, you know, when you, when you talk about concepts. So sustainability in the pavements world, it stands on three pillars, which is your economic, environmental, and social. So it has to do good to people, which is your social and then profit, which is economics, and the planet, which is environmental.

So Understanding that, you know, you need to have a balance of the three to be sustainable. And it's not just environmental, or it's not just economics it has to be a balance. That is one of the things. Another big misconception, which, Aparna, you and I were talking while we were on that Southwest flight to DC was, you brought up the topic about zero emission vehicle or zero emissions, and I told you immediately there's no such thing as a zero emissions right? Everything has an emission associated with it. If you look deep enough, right? I mean physicists would say that entropy always increases. If there's only one direction it can go, there's no such thing as zero emissions. And I think we talked about more specifics there to substantiate that everything consumes energy. It needs energy to be produced.

So a windmill cannot be zero emissions because there was some energy that was used to produce it or manufacture it. When you talk about vehicles, and this is where our conversation started, was with vehicles, a vehicle cannot be zero emissions because a vehicle was manufactured, there is some emissions associated with it. Let's say it doesn't have tailpipe emissions, it's very possible that that vehicle is battery operated and is heavier, and that means it probably burns through tires more than a combustion vehicle. That's because of the added weight and who knows how much repair and maintenance it requires. Those are also associated, you can associate emissions with, all these activities. So there's no such thing as zero emissions but not to take this the wrong way, you have to know how you can reduce those emissions. There are, there are ways to do it, to bring down your emissions, so that we don't just get arrogant putting those emissions out there. 

Another thing is, another misconception which I come across very often in our industry is, about recycling. When somebody says recycling is good and recycling is sustainable, it is untrue. Recycling is not equal to sustainable because when you recycle something, you really have to look at its functional performance. 

I think this is Alejandra in episode two of this podcast who was talking about performance of her cell phone. I think she was comparing her phone to an iPhone and she went into the functionality. It works as a phone, but it can do other things. right. So again, recycling is not sustainable or is not equal to sustainable. I say that because you have to look at it from its functional performance and its functional use. When you look at a lifecycle approach, if you recycle something, you put recycled plastics in your pavement. But if it doesn't last, instead of lasting 20 years, it lasts only 10 years. That means, you know, halfway through its life, you are adding to those emissions and you have to account for it. This is the lifecycle approach that's used in sustainability. 

So what I would like the audience to take away from here, the listeners to take away from this, is recycle by all means, but do it in a scientific manner, go through the process of assessing it to make sure that you're not taking something away, when you're using recycled materials, in, the product that you're creating, the newer product, and it lasts just as long or has an equal or better performance.

[00:18:10] Aparna: Very well put. Love that Kiran and also wanna take a second and give you a huge compliment. Our number one fan is now a guest on our podcast. This is excellent memory recall guys, eat your carrots, eat your vegetables. Kiran's brain is A+ right now. He's remembering everything and huge thanks for being such an avid listener!

[00:18:29] Kiran: Speaking of vegetables, I'd like to suggest that you spell your name as Green Collar Pod, P-P-O-D-S. Ask me why. 

[00:18:37] Aparna: Why?

[00:18:38] Kiran: That gives you two P's in a pod.

[00:18:41] Aparna: He's a dad. He's a dad with jokes. If you can't tell, this is our humor. So thank you so much for playing into it. 

[00:18:48] Kiersten: You seem especially adept at recalling information as well as sharing information. In the episode you've talked about how you share things with your kids or maybe people at parties, and I, I wanted to ask: In this industry conferences and presenting research are huge ways that you've been able to share ideas and to foster collaboration. Are there any conferences in specific, that you feel have been more inclusive of sustainability or incredibly useful to you?

[00:19:16] Kiran: That's a good question and that's something that a lot of engineers at work also ask and students that I come across when I'm at conferences ask me, “what are the kind of conferences should we attend or, where do we start?” One of the conferences that I often like going to is put together by a National Academy of Sciences. It's called the Transportation Research Board that happens in Washington, DC every year in January and that was the flight I was on when I met Aparna. That is one of those where you can go and volunteer and help the committees that are within and you can choose any of the committees. Most committees talk about sustainability or in some fashion responsible engineering where you are taking care of one or more aspects of sustainability. Other than that, I would say any other conferences that you go to, if you can talk and you can find a speaking position I think that was again, something, was it Christina who was talking about it? One of the episodes about finding speaking opportunities? If you can, share your ideas in a convincing way, and in a scientific way, you can make any conference exposure to sustainability.

[00:20:23] Aparna: I love that, Christina, you're already having an impact. Moving from your professional life to your personal life, we were wondering if there are ways that you practice sustainability in your day to day outside of work?

[00:20:33] Kiran: I definitely do. All of this started after I got more and more involved with sustainability, very unknowingly at work. Now, the way I do this at home is, since I have children, an easy way to start is by starting with them.

But even before that, my wife, after we got married, she actually brought in, she came with a recycle bin. She came home with suitcases, but also she brought a recycle bin. So, she started making me more conscious of the things I'm doing at home and that's when we started using more paper products that we could actually recycle and also consuming less water. 

Now, I also don't use paper anymore to write. So that is something that I've started doing. And I think, I don't know if you saw, I had a remarkable paper tablet that I use, instead of using paper. So reducing water consumption and not using paper are the two things that I do at home.

Now, both those things can be recycled and you could use it more than once. Right? So the third thing I try you know, there are ways that you can consume less energy at home. By that I mean electricity and that is something that I work with my daughter who's the older of the two children I have, and I try to teach her how you can reduce energy consumption. And then, what we did, my wife and I, is that we made sure when we bought the house, we looked into the energy efficiencies. When we remodeled the house, we made sure we got double paned windows.

We went through the process and I think that these are the kind of things that Aparna, you talked to your clients about. 

[00:22:01] Kiersten: Absolutely. You mentioned that you never dreamed of being a pavement engineer as a child, but I would like to believe that someone listening to this episode is going to be inspired by everything you've shared. For that person who now wants to do what you do. Are there any particular skills or certifications that you would recommend they get?

[00:22:21] Kiran: I'm very flattered that you would say that. At home, my daughter definitely likes to talk about cracks on the pavement and so, so does my son. He's just learning, you know, his, forming sentences, but he talks about, more about pavement. So It's very flattering that I that kind of inspiration on the younger folks.

But getting more serious, at work, I'm trying to speak with the owners of my company to see how we can spread the word about this field and how we can be a responsible engineer in any field or, in general engineering. but The certifications to begin with, to be a pavement engineer, you need to be an engineer. It could be a civil engineer or mechanical engineer and then you just learn the sciences of pavements and you can apply your engineering skills to it. Since this is a sustainability podcast, and if we were to talk about sustainability specifically, I do not have any certifications related to sustainability. However, I have friends you know, it's not about what you know, but who you know. Right? So I have friends who have certifications provided by organizations such as APLCA, and they're called the LCA Certified professionals who can perform a lifecycle assessment that can measure and quantify sustainability or, look at different alternatives based on their functional use.

[00:23:39] Aparna: Thanks for sharing that one. I have not heard of it before, so I keep learning so many things in our conversation Kiran, this is great. So similar train of thought, If listeners wanna be involved in the sustainability shift, outside of certifications, are there any books? Documentaries? Other resources that you'd recommend to them?

[00:23:56] Kiran: There definitely are lots of books out there and resources out there to get you into sustainability or get you thinking about it. There is one book that is sitting on my shelf that's called Energy and Civilization: A History by Vaclav Smil. I hope I didn't butcher that name but, that's a book that I've been meaning to read, but just like Gretchen mentioned in episode five, I cannot read these books after I do a whole day's work. I have to go and read something else. So currently I'm reading four other books, but I do intend to get back, and read this Energy and Civilization: A History someday. 

Outside of this, you would really like this answer when I say that, if there is a resource that I would recommend is this very podcast because you cover so many diverse employment and life, that this is the podcast that people should listen to and get a new perspective or different perspective if you're in a different field. 

[00:24:50] Aparna: I am so flattered. I wanted to say too, on the topic of the Smil book, I have also owned it for about three years now. Do not tell my graduate school professors, it was never read. So I feel you very much there. If SparkNotes wants to take it up and give us like a five minute summary, I'd be all ears.

[00:25:08] Kiersten: Well, we like to be realistic and aspirational here, right? So realistic: maybe we don't read every book that we're interested in, but on an aspirational note, and to close out here today, Kiran, I would love to hear what legacy you hope to leave behind in your work.

[00:25:23] Kiran: I've never thought of leaving behind a legacy. I guess I haven't reached that stage, but because I have children and what I talk to them about, usually, I think that's the best way I can put this and I have young engineers who are working with me and starting off their careers.

So it's, very enjoyable working with the, these young lines. What I would usually tell them, what I tell my children is, don't stop questioning. When you see something and you wanna learn more about it, the best way you can learn about it is by questioning and learning it, and then going and teaching it once more. Right? Because when you teach it, then you learn better. No better way of learning. And then what I tell, grad students or the younger engineers who work with me is, I don't stop at, "don't stop questioning", but I also say, “go home and look it up”, or “go back to your desk and look it up”, because that really helps, creating that genuine curiosity in research and learning about things and applying what you learn. It's not along the lines of sustainability, but hopefully, these things that I usually tell people, will in fact, help them develop into individuals that would sustain our planet and our civilization. 

[00:26:30] Aparna: Stay curious! There's no such thing as a stupid question, and there's so much to learn in this world, right? You wanna try and take in as much as we can. So thank you so much again, Kiran, for being on the podcast, for being such a phenomenal guest. We've had such a good time and learned a crazy amount in just the short amount of time that we had together, so really appreciate the time and we can't wait to follow up and see how you're doing in the future, and we will sign off as two peas in a pod.

[00:26:57] Kiran: Thank you so much for having me on here, and I really liked the way you signed off.