Ep. 332: Why do Indian roads fail so quickly? with Prathap Rao

The Gyaan Project

Prathap Rao discusses the engineering failures behind Indian roads, specifically focusing on why potholes are a persistent issue due to wate

Key takeaways

• Water is identified as one of the primary enemies of asphalt, leading to disintegration and potholes.
• Prathap Rao's journey transitioned from a corporate leadership role at HP to founding PotholeRaja and GridMats.

Main topics

• Mechanics of road failure
• Recycled plastic in infrastructure

Notable quotes

Pothole fixing is important, but it is a corrective measure. It is a post-mortem.

Conclusion

The episode highlights how material science and structural innovation

Transcript preview

Speaker 2 (0:00) When I started looking at the top three, four issues on road safety, I mean, mobile usage to helmet accidents to seatbelts not wearing and people dying. I mean, all these are genuine concerns. But what I realized that the issue is potholes. Then media picked up saying that somebody is fixing potholes, somebody is crazy to go out in the middle of the night. That became really viral. So potholes generally are more prone in asphalt. The water, when it comes, it has to go to the side drains. The water should not go directly down to the soil. And water is one of the biggest enemies for asphalt. We are seeing if we can use grid mats with automated sensors to track temperature, moisture, improve air quality. We have used solar panels on top of it for harnessing solar energy. I mean, pothole fixing is important. But it is a corrective measure. It is a post-mortem. We are fixing something that is broken. Can we build roads that doesn't require that often repair and maintenance? Speaker 1 (1:00) Hello and welcome to Engineering the Everyday with Kodari's Design Lab and the GAN Project. This series looks at how India is building its next decade across energy, materials, manufacturing, mobility, AI, and the spaces we live in. We speak to experts shaping these everyday systems. Today we have Dr. Pratap Rao with us. He's a founder of Pothole Raja and the mind behind GridMaths, a system that uses recycled plastic to rethink how roads and other hard surfaces are built. In this episode, we unpack why potholes happen, what really goes beneath the road, why infrastructure innovation is so slow, and how new materials could help India build better and more sustainable infrastructure. Before we begin, please do subscribe to the Godrej Design Lab and the Gyan Project YouTube channels and other social media handles to stay tuned with the upcoming episodes, short bites and insights from these conversations. Let's begin. Welcome Pratap to Engineering The Everyday. Thanks for giving your time and it's an honor to speak to you. It's my pleasure. Thank you so much. Cool. So I generally avoid or I've been like practicing not really going down the personal memory lane, but your work is fascinating. So before we jump into the subject of the day, I would like to understand your journey has been fascinating from like, being a pilot to big corporates to fixing potholes and now grid maths with a PhD along the way. Could you briefly share like these crazy transitions and what motivated you to do like such huge body of work? Just a background about you. Sure. Speaker 2 (2:35) Thank you. Of course, it's been amazing life journey, different phases of life, being one of the best gerets in the system. Very early in my life, getting an award from the prime minister. I watched my back then going to UK youth exchange, getting exposure to quite a few varieties of countries and armed forces, getting licensed to fly before I get a driving license. I think these are amazing, very early parts of my childhood, I would say. But I then moved on to the armed forces a bit. When I say a bit, because it was short-lived, I had to move on from the flying. on the medical grounds and then moved on to corporate life. Spent about 11 years in senior leadership roles at different organizations, companies like Citibank, Aditya Birla Group, Hewitt. And my last employment as with HP as a global VP in Speaker 1 (3:26) the Speaker 2 (3:26) US, Speaker 1 (3:26) managing the Speaker 2 (3:27) large portfolio of business process transformation. And in that process, I had done a couple of masters and a PhD and exposure to Harvard and MIT in the US. for different varieties of studies. And then finally it hit saying that I should do something much bigger and more impactful. And that's when the entrepreneurship journey started back in 2011. Yeah, it's been almost 15 years Speaker 1 (3:51) that I've Speaker 2 (3:52) been consulting, education. Then 2015 is Portal Raja, which got triggered with multiple contexts, I think. A lot of students inspired me because they were doing projects in their school part of one of our social action projects curriculum that we drive. And that made a lot of trigger to saying that a 15 year old for a school project can make a difference to society. With all my background, what am I doing? And that's, I think, one of the triggers out of many. And then I had a look at what are the things that I can do as an individual to look at material science side or... the innovation in infrastructure or sustainability. So these were some key words that really hit hard. And I believe that's the foundation that got started to where I am today. Speaker 1 (4:40) It's very, very inspiring. Yeah. So we'll jump for the today's topic, which is mainly understanding the material behind roads, grid mats, and many more things. But you joked once that Bangalore has most PhDs in India. And what you meant by PhD is like pothole drivers. So when did you think like the first look at a pothole and think that it's not like a maintenance problem, but a material problem? And that's my understanding, but you can elaborate on that more. Speaker 2 (5:09) Yeah. So, I mean, I mean, it's been perennial, I'm sure. As long as you're driving, you ask your grandfathers who... moved on the road, they will say bad roads to even the new generation. So roads have been plagued with chickenpox, I would say, long enough. And one of the challenges that engineering side probably has not been able to address is the asphalt issues when it comes to water logging or drainage or quality of material, the quality of engineering. So it can be a combination of these variables, but... The more social challenge that I will see is the behavior of, can I fix this before it breaks? And I think that's not evident in a lot of our current contracts or terms that are prevalent in the municipal council, especially in public roads. So, and it may be because of many reasons, both known and unknowns. But I think potholes definitely are out of so many things that I was initially researching before I got into this. I mean, there are so many road safety issues. We were quite serious in the education space. We did quite a few work on the road safety education, talking about how do you make children safely cross roads? How do you understand traffic? How do you decongest some places? So those are more on research initial thinking. But when I started looking at... The top three, four issues on road safety, I mean, mobile usage to helmet accidents to seatbelts not wearing and people dying. I mean, all these are genuine concerns. But what I realized that the unknown, which is absolutely unaddressed and globally it's been an issue is potholes. Back in 2015, when I was researching, the Supreme Court had given data around 850 people died out of terror attacks during that phase of Speaker 1 (7:07) research, which in 2012-15. And Speaker 2 (7:10) in the same period, 4,500 people died out of potholes. So it's much more dangerous than terror attacks was the insight from that. And I think it's a global challenge. It's not just the life and death, of course. It's also economic loss, car crashes, your bumper repair, maintenance. The amount of times people get injured. There are so many other side impacts that happen because of one unknown crater on the road. So on the aspects of how do we address these potholes? I mean, I'm not a civil engineer. I have studied mechanical. But I think civil was more an innovative connection to me, though my mother is a civil engineer. that wasn't influencing potholes related studies but the intrigueness of connecting to how do we repair maintain how do the good roads we have traveled i mean i had a good opportunity to be out of the country for a long time and i have been exposed to some of the companies who i was consulting in malaysia singapore dubai and even indonesia which was not as economically better off than india but the roads were much better well maintained well kept not many unknowns of traffic. Of course, population is one variable which we have the highest, but there also densities are pretty high in the metro commutes. But the roads are much better maintained. And I was management consulting with one of the large, like our public sector in India, they call it GLC, government-linked companies in Malaysia and Singapore. They Speaker 1 (8:47) have Speaker 2 (8:48) the large maintenance of public roads, repair and maintenance. When I was doing leadership development for their team, and I was very fortunate to understand the material side, the machines, the innovation that they are looking at, what are the repeated methods of maintenance. So that was one side of the initial exploration. The other one is when I was in, I think, both US and Europe, you could go to a hardware shop and buy cold asphalt. You know, you can just get it and fix it on your own. If you see anything around your house, you know, your pathways and exits and things. I think that was very, uh, uh, interesting for me because I had not seen that in India. And that's the first time I said, can I do something on this? Uh, initially I imported from my own personal money, some, uh, five bags from us. Costed a lot to fix a pothole. I think I initially spent about 25, 30,000 rupees for one pothole. But I think it was worth it. I got that exposure and understood what are the components on the cold asphalt. One important thing about cold asphalt is you don't need heating. It can be stored for long. It can be ready to use mix, which is just directly poured on a pothole. Even if there is water or uneven surfaces, it can directly be poured. So that was very, very unique. product at that time, a miracle product for potholes. And that's the research work that I started. And that gave me confidence that it can be Speaker 1 (10:17) something Speaker 2 (10:17) which Speaker 1 (10:18) we can fix. Speaker 2 (10:18) Then I started looking at more university connected research to understand, can we add plastic waste into it? Can we add crumb rubber? Crumb rubber is typically your recycled tire powder, which is also waste. So those were initial research, got some good amount of IP around it. Yeah, then media picked up saying that somebody is fixing potholes, somebody is crazy to go on and meet up the road middle of the night, then doing something about it. And that became really viral. Yeah, I mean, that's the journey it got started off 2005. Yeah, yeah. No, Speaker 1 (10:52) I'll add more links to this for people who want to deep dive there because there's enough YouTube material and, and your other podcasts also. Okay, so we'll come to this. point of asphalt and the material much later but you mentioned that it's a problem globally you mean like is it like as severe as it is in India or it's yeah see if Speaker 2 (11:14) you look at some of the reports from the US Europe there are surveys about how people are frightened one of the most top three you know risk factors that a commuter in the US feels that you know they are always scared of is potholes. UK, even last few years, they spent about close to about two and a half billion pounds in just fixing potholes and road repair. So it's a global issue. Most so-called economies, which are much better off, have this same issue. Even with less populated countries as well, you know, I have been invited at Africa or some of the southeastern countries. Density is not as... much but still similar issues because it's more an engineering issue and then second of course is the social and behavioral issue of maintenance and upkeep and other things. Got Speaker 1 (12:08) it, got it. I was fortunate to interview Naresh Narasimhan. Yeah. on the GAN project and we spoke about design of Bangalore and in that he spoke about the Church Street, how it was designed and so on and so forth. But definitely road is not like the asphalt that we see, right? And you said you're not like a civil engineer background, but if you could help us also explain what goes beneath asphalt, right? Because we drive there and then where the leak link is, which causes these potholes, is it like... the sub-base, where does it, like why does a pothole happen also? Speaker 2 (12:48) Yeah, sure. I mean, imagine a sandwich, right? Typically, multiple layers of different kinds of material being laid on top of the soil. Generally, when you make a new road, if you see the first and foremost work has to be done at the soil level. Now, that soil over a period may have got extremely exposed to... water or other impacts over a period of time. Now, if that is not addressed, it can start settlements. You would have seen suddenly a road being bumpy. The top surface still sees nice, but suddenly you feel that you're going on a roller coaster, right? That is because the soil has settled. The soil has gone below its compacted densities. So one of the most important thing is to address the soil issues. Now, what happens? After being completely a new role, now I may have addressed that soil issue initially, but because the drainage systems may not be appropriate, because of the compaction levels, the number of times they have compacted, if those are not as per the required standards, then it can settle even after that time. Now that is more a post-mortem work. That's where issues get to address. It's like you've built your house, but your foundation is weak. You can't... just demolish your first floor, second floor to build your foundation. You have to still do some patchwork to manage the entire building. Now, the advantage with road is you can do resurfacing, but it is a costly affair and it uptops the traffic. And most of the public roads, even at midnight, people still have a curfew when you're not doing any work. So that's an engineering issue. One is the soil structure as to how do we address it. It can be compacted, it can be managed, it can be stabilized. There are different types of soil. So technically, if you look at, if you go to Maharashtra, you'll see a lot of black cotton soil, which is very like a soft sponge. You know, it absorbs water. So it's very slushy. It's very, very tough to manage. But roads are good in Maharashtra as well. It's not that you can't do it. So it's a very different application when different types of soils are there. Then on top of it, there is a layer which is for water erosion or water management, which is called granular sub-base, GSB, which is typically, imagine an inverted funnel, right? So the funnel opening at the top and the bottom. Now the entire road design is in such a way that when there is a load on the top, imagine a truck on the top of the tarmac or the road, the load of that truck will disperse like an inverted funnel. Now that inverted funnel... logic is the load needs to be distributed gradually down at a horizontal space but by the time it goes to the soil it should have been absorbed. So each layer acts as an absorbent layer. So the load is distributed. So the way the design is also done is the gravel size, the composition of the aggregates which is maximum load which is the rocks that are put in are highest at the bottom and then the size of these gravels reduces as it goes higher. That's how the design happens. So if you look at the granular sub-base, it has a large 60 mm, 80 mm gravels. Some of the rural places, they even put boulders, you know, as the bottom. And as you go up, there is a next layer, which is called WMM layer, which is wet mix meccan, which is mostly moisture layer. You know, it has more soil and sand and, you know, more finer gravels and finer particles, maybe even dust. which actually acts as a more binding factor. That is where the load starts to hold well. So if that WMM layer is held well, the load distribution doesn't go anything below. If that starts to break this metal, then it goes to the next layer and then maybe the soil. And then for asphalt, generally, there are two layers. So above the WMM, there is a layer called dense bituminous macadam. which is actually the load bearing of the asphalt. The gravel size are generally about 20 mm or down and has bitumen, which is binding these gravels, holding very well. So that's a layer first put. Generally, you would have seen the asphalting process. They would first do the DBM layer, maybe between 50, 40