Latest / Thinking Transportation: Engaging Conversations about Transportation Innovations / One Size Doesn’t Fit All: Maintaining our roadway infrastructure demands a varied scientific approach.
Transcript
- 0:14Bernie Fette (host): Hello again.
- 0:16Bernie Fette (host): This is Thinking Transportation-- conversations about how we get ourselves and the things we need from one place to another.
- 0:24Bernie Fette (host): I'm Bernie Fette with the Texas A&M Transportation Institute.
- 0:30Bernie Fette (host): If we judge things on appearance alone, it's easy to think that streets and highways are almost indestructible, strong enough to bear the weight of countless cars and trucks day after day and year after year without fail.
- 0:46Bernie Fette (host): And though many of us don't realize it, there's a lot of science, chemistry, and engineering that goes into keeping those driving surfaces in good shape.
- 0:56Bernie Fette (host): That's our topic today with Tom Scullion, a senior research engineer at tti, and an expert in pavement maintenance and repair.
- 1:06Bernie Fette (host): Tom, I know you've been super busy and you've been traveling a lot.
- 1:11Bernie Fette (host): We're really grateful you could make time to join us today.
- 1:13Bernie Fette (host): Thanks, Tom.
- 1:14Tom Scullion (guest): My pleasure.
- 1:16Bernie Fette: I know we're gonna try to talk about a number of new things in your work today, what you can do to help roads stand up to the vibrant energy industry in Texas, environmentally friendly ways to, to repair pavements.
- 1:30Bernie Fette: Yep.
- 1:31Bernie Fette: I was hoping though, that we could start at a more basic level, particularly for listeners who don't know anything about road building.
- 1:38Bernie Fette: Those of us who don't think about roadway maintenance unless we run over a pothole.
- 1:43Bernie Fette: So can you give us a picture of the major steps that go into building a street or highway?
- 1:50Tom Scullion: Yeah.
- 1:51Tom Scullion: Most of my experience, vast majority of my experience has been in Texas and I, I think when we talk about building roads in Texas, it's not one size fits all.
- 2:02Tom Scullion: We've got a state here with just about everything.
- 2:06Tom Scullion: If you go from east to west-- in east Texas, you have some really poor soil conditions and you have a lot of rainfall.
- 2:15Tom Scullion: You go to west Texas and you have very good soils, very good subgrade materials, very little rain.
- 2:22Tom Scullion: That's an ideal situation.
- 2:23Tom Scullion: You go to south Texas and you have very pleasant climates.
- 2:28Tom Scullion: You go up to the panhandle and we get several feet of snow.
- 2:31Tom Scullion: Mm-hmm.
- 2:32Tom Scullion: .
- 2:32Tom Scullion: So like I said, road building in Texas is not one size fits all.
- 2:37Tom Scullion: Texas is blessed with some of the worst soils in the whole United States.
- 2:41Tom Scullion: Uh, that is these expansive clay materials that we find anywhere east of Interstate 35.
- 2:49Tom Scullion: Okay.
- 2:50Tom Scullion: Uh, these are the soils that when they get wet, they expand, and when they get dry they shrink and crack.
- 2:57Tom Scullion: All of these issues I'm bringing up now are to do with the challenges of building roads in the state of Texas.
- 3:04Bernie Fette: Okay.
- 3:05Tom Scullion: Now, road building really started maybe a hundred years ago, and the big drive back then was to get the farmers out of the mud.
- 3:16Tom Scullion: And the first thing you have to do with these roads that we built was you have to have a stable foundation.
- 3:24Bernie Fette: Okay.
- 3:24Tom Scullion: Now, if you're working on this very poor soils that we have, how do you get a stable foundation?
- 3:30Tom Scullion: Well, you have to chemically treat it.
- 3:33Tom Scullion: So Texas probably uses more lime than the rest of the whole United States together because of the very sorry, nature of the soils that we have to build it on.
- 3:44Bernie Fette: Okay.
- 3:44Bernie Fette: And so you have to do a lot of things to that soil.
- 3:47Bernie Fette: And when we're talking about soil, we're talking about more than just the dirt.
- 3:49Bernie Fette: You're talking about the clay, you're talking about the rocks that are in it, the other organic matter like roots and grasses and such.
- 3:56Bernie Fette: Yes.
- 3:56Bernie Fette: All of the things that you're talking about have to be done to make the soil essentially more stable.
- 4:02Tom Scullion: That's right.
- 4:03Tom Scullion: Okay.
- 4:03Tom Scullion: We need a, a stable foundation.
- 4:05Tom Scullion: Right.
- 4:05Tom Scullion: To put a road on it.
- 4:07Tom Scullion: Now, when we started, the vast majority of that payment structure in the rural areas was this lime stabilized subgrade where we needed it, six inches of limestone material, and then what was a surface dressing, which is just a shot of asphalt and a layer of rocks placed on top.
- 4:26Tom Scullion: Okay.
- 4:26Tom Scullion: Those things, if they're designed properly, really got the farmers out in the mud, so that's okay.
- 4:32Tom Scullion: Kind of where we started.
- 4:34Tom Scullion: Now, the other thing which drives the whole payment design side of things is the amount of traffic on the roads.
- 4:41Tom Scullion: And I'm sure you've heard the statistic before for the last, oh, I don't know how many years, there's been a statistic that there's a thousand people a day moving to Texas.
- 4:51Bernie Fette: Right, right.
- 4:52Bernie Fette: And they all bring their cars and trucks.
- 4:54Tom Scullion: They'll bring in two cars with them.
- 4:55Tom Scullion: And so then we have many more vehicles on the roads and subsequently because of the influx of people coming here, we need new roads, but we also need new buildings and highways and schools and all this kind of good stuff.
- 5:10Tom Scullion: So that drives the whole economy, the construction economy, not just of roads, but of buildings that's putting more load on the roads that needs to be, you know, accounted for.
- 5:19Bernie Fette: Because a lot of the same things that you're using to build roads, you're also using to build those, those office buildings.
- 5:25Bernie Fette: Yeah.
- 5:25Bernie Fette: And schools and such.
- 5:26Bernie Fette: Yeah.
- 5:26Bernie Fette: Okay.
- 5:27Tom Scullion: The basic road system was really put in for the farmers, but then when we have this tremendous growth and then we have the focus on moving the cities, we've gotta modify things to handle those situations.
- 5:38Bernie Fette: Okay.
- 5:39Bernie Fette: So you started out with this goal of getting the farmer out of the mud.
- 5:45Bernie Fette: Mm-hmm.
- 5:46Bernie Fette: , and we've proceeded to a more modern Texas where urban areas are growing at an extremely fast clip.
- 5:53Bernie Fette: Mm-hmm.
- 5:53Bernie Fette: , uhhuh,.
- 5:54Bernie Fette: Those things taken into consideration once you've built that, that stronger foundation for those roads and put the surface on them and put those roads into use, how long can you reasonably expect those roadways to last before the pavement needs to be maintained or fixed?
- 6:09Tom Scullion: When these things are initially designed there, there's two types of pavements that you see when you move to the cities.
- 6:16Tom Scullion: One is asphalt pavements, right.
- 6:18Tom Scullion: Where we have a layer of the black stuff, which covers our base material.
- 6:22Tom Scullion: Our base material is usually, typically just a layer of limestone, aggregates that is compacted and whatever.
- 6:28Tom Scullion: Then we put certain thicknesses of asphalt on top of that.
- 6:32Tom Scullion: What has become really popular in the urban areas is the other type of payment that we see a lot of is concrete payments.
- 6:40Bernie Fette: Right.
- 6:40Bernie Fette: And you're getting to, one of the questions I was hoping to ask is why we have those two different types.
- 6:45Tom Scullion: The feeling right now with with folks like the Texas Department of Transportation is that when we get into the urban areas, and I'm talking about the urban areas of Houston, and I'm talking about the urban areas of Dallas.
- 6:57Tom Scullion: Mm-hmm.
- 6:58Tom Scullion: , that's where we have requirements on there.
- 7:01Tom Scullion: Man, man, we want to get in there.
- 7:03Tom Scullion: We want to do whatever we're building and we don't want to come back for 30 years.
- 7:07Tom Scullion: The consensus is that the concrete pavements in those brutal conditions usually hold up better.
- 7:15Tom Scullion: Okay.
- 7:15Tom Scullion: You know, or give us those long life.
- 7:17Tom Scullion: Now there's a whole history of road building in the urban areas and I think, uh, the Texas Department of Transportation has really done a, a good job of designing payments to last in those areas.
- 7:32Tom Scullion: They go through this foundation stuff again, when you get into the areas of Houston, because Houston's on some pretty poor soils.
- 7:40Tom Scullion: They go with lime stabilized layers, uh, base layers, and then they'll put 12 to 14 inches of concrete as the wearing surface.
- 7:48Tom Scullion: Mm-hmm.
- 7:49Tom Scullion: , those typically, you know, don't give you any problems till after at least 20 years.
- 7:55Tom Scullion: Their design life is normally 30 years.
- 7:57Tom Scullion: That's what they're designed for.
- 7:59Bernie Fette: Okay.
- 8:00Bernie Fette: As opposed to asphalt roadways, which you can expect to last about how long?
- 8:05Tom Scullion: Normally the asphalt roadways are designed for 20 years.
- 8:08Tom Scullion: Um, and the expectation in the design process is you will not do anything to these roads for 15 years.
- 8:16Tom Scullion: At 15 years you'll have to do some resurfacing.
- 8:20Tom Scullion: You know, you should just have like a surfacing problem where you need to come and redo the surface of the road because maybe it's got some minor cracks in it.
- 8:29Tom Scullion: Mm-hmm.
- 8:29Tom Scullion: , or maybe it is got some skid resistance type problems.
- 8:32Tom Scullion: So for a national payment, normally in year 15 when they're built for this urban situation, normally in, in that situation you'll be coming to do some milling and a, a new surfacing after say 15 years.
- 8:47Bernie Fette: You're talking about the differences between concrete and asphalt pavements, how long they last.
- 8:52Bernie Fette: One of the things that a typical traveler is probably most familiar with whenever they encounter a maintenance issue is the pothole.
- 9:01Bernie Fette: Mm-hmm.
- 9:02Bernie Fette: .
- 9:02Bernie Fette: Mm-hmm.
- 9:02Bernie Fette: .
- 9:02Bernie Fette: And so just to give us a little bit of a engineering 101 or road maintenance 101 explanation, why do potholes happen?
- 9:12Tom Scullion: I would say that the main reason is the combination of, um, overloaded vehicles and bad weather, heavy rainfall.
- 9:22Tom Scullion: And you know, we have a hard time regulating the loads that drive on these roads, especially, you know, the energy sector stuff going on and what have you.
- 9:31Tom Scullion: But sometimes the roads, maybe there were designs for a certain level of traffic, and we'll talk about this later too.
- 9:38Tom Scullion: And the level of traffic might have gone up by a factor of 10 and there's 10 times more loads on the road and what have you.
- 9:45Tom Scullion: Now, if we're talking about potholes in asphalt pavements, normally what happens is because of the traffic on it in the environment and what have you, you get some kind of cracking going on.
- 9:55Tom Scullion: Okay.
- 9:55Tom Scullion: Then what happens is you get rainfall going in there, the surfacing is supposed to protect the base from wearing out.
- 10:03Tom Scullion: Now if that surfacing cracks, you get rain into it, you get moisture into that limestone base down there, all things go bad.
- 10:12Tom Scullion: So increased traffic loads, payments that will never designed for those roads, surface cracking, water getting in, but you have potholes.
- 10:21Bernie Fette: Right.
- 10:22Bernie Fette: And you mentioned the extra load on roadways that weren't built to handle those roads.
- 10:26Bernie Fette: You specifically mentioned roadways in the energy sector, Permian Basin and other parts of Texas as well.
- 10:32Bernie Fette: And not just Texas, but anywhere in the United States where the roadways were built for a particular type of traffic, perhaps cars and pickups and maybe the occasional tractor, but now they're standing up or those roads are trying to stand up to much, much heavier loads.
- 10:52Bernie Fette: Mm-hmm.
- 10:52Bernie Fette: due to circumstances that were not foreseen years before when they were designed and built.
- 10:58Bernie Fette: What are some of the challenges that you're running into there, especially since those are relatively recent developments in Texas and and how have you been dealing with those?
- 11:06Tom Scullion: Yeah, that's what I've been dealing with Bernie for the last 10 years, and that's when the energy boom really kicked off in both south Texas and in the Odessa area.
- 11:18Tom Scullion: Mm-hmm.
- 11:18Tom Scullion: , Permian Basin.
- 11:19Tom Scullion: Mm-hmm.
- 11:20Tom Scullion: , and as I say, those roads were never built for the loads that are on them.
- 11:25Tom Scullion: The energy guys are what drives the economy of Texas.
- 11:28Tom Scullion: So we need to, you know, accommodate this stuff.
- 11:31Tom Scullion: And so the challenges that were put in there is that you have a road that was designed for 500 cars a day, and all of a sudden that road is carrying 500 trucks an hour.
- 11:45Tom Scullion: I mean, the roads in both areas, south Texas, in the Odessa area were totally destroyed.
- 11:51Tom Scullion: The farm to market network over there was totally destroyed.
- 11:54Tom Scullion: Mm-hmm.
- 11:54Tom Scullion: .
- 11:54Tom Scullion: So we got into working with the Texas Department of Transportation to say, well, what the heck can we do?
- 12:02Tom Scullion: Well, TxDOT made the challenge even more interesting because they said, okay, you guys, you need to come up with a fix.
- 12:09Tom Scullion: We need to widen these roads, we need to strengthen these roads.
- 12:14Tom Scullion: But the one kicker on top of that stuff is whatever you folks do, we're putting the energy sector traffic on it that night.
- 12:21Tom Scullion: So whatever repairs you come up with, you've gotta get outta the way at five o'clock and we're putting the energy sector loads on it.
- 12:29Bernie Fette: So fix it right.
- 12:30Bernie Fette: And fix it fast.
- 12:31Tom Scullion: Fix it fast.
- 12:32Tom Scullion: That has been what we have been working on intently for the last seven or eight years at least.
- 12:39Tom Scullion: And what we do, these are roads in rural areas where you really need to figure out how to take the existing structure and strengthen it.
- 12:50Tom Scullion: But you've also got that additional requirement on it of, you know, um, how can we put the traffic on it early?
- 12:57Tom Scullion: And we're talking about fully loaded energy sector trucks here.
- 13:01Tom Scullion: Okay.
- 13:01Tom Scullion: We're talking about going in there, doing something to the road, mixing it up, leveling it out, and then within two hours putting traffic on it.
- 13:07Tom Scullion: The traditional approaches didn't work.
- 13:09Bernie Fette: And just for a perspective, you were having to accelerate procedures to a degree.
- 13:15Bernie Fette: Yeah.
- 13:15Bernie Fette: Leveling things out, fixing it, and two hours later putting traffic on it in the past, or if this was not an energy sector roadway, how much time would be allowed for the processes that you're talking about?
- 13:26Tom Scullion: Oh, you can keep the road closed for two or three days while you get everything looking pretty and make sure everything is gonna hold up and what have you.
- 13:34Bernie Fette: Two or three days versus two or three hours.
- 13:36Bernie Fette: Yeah.
- 13:36Tom Scullion: Yeah.
- 13:37Tom Scullion: This, okay, this, remember what we're talking about here is minor roadways in the boonies where there is no detour available.
- 13:44Bernie Fette: Right.
- 13:44Tom Scullion: And you've got major energy sector development going on along the route.
- 13:50Bernie Fette: Because time is money.
- 13:51Tom Scullion: Get in there, fix it, and get outta the way.
- 13:53Tom Scullion: Right.
- 13:54Tom Scullion: There's a challenge.
- 13:54Tom Scullion: Okay.
- 13:55Tom Scullion: Now what we've been doing and what we've promoted and what is working very well is coming up with a combination of different materials.
- 14:03Tom Scullion: And this gets into a lot of things.
- 14:05Tom Scullion: This gets into the whole concept of improving our pavement recycling processes.
- 14:11Tom Scullion: Mm-hmm.
- 14:12Tom Scullion: Recycling is where we come and evaluate the existing structure, mix it all up with a huge reclaimer, put some kind of stabilizer into it, we will then compact it and roll it.
- 14:24Tom Scullion: We will not put a surfacing on it, but then we'll put the traffic on it.
- 14:28Tom Scullion: So the challenge for us is what kind of treatment can we apply to this thing to facilitate this rehabilitation option?
- 14:37Bernie Fette: So you're grinding up an old roadway, you're mixing in newer materials, and then using that combined product to build a new driving surface.
- 14:46Bernie Fette: Right?
- 14:46Tom Scullion: Yes.
- 14:46Tom Scullion: Well, it is gonna eventually have some kind of surfacing on it.
- 14:50Tom Scullion: Okay.
- 14:50Tom Scullion: But we want to make it stable enough that we can drive on whatever we finished at the end of that day.
- 14:57Bernie Fette: Even if it doesn't have an asphalt surface on top.
- 14:59Tom Scullion: It doesn't have an asphalt, it doesn't have a seal coat.
- 15:01Tom Scullion: Nothing.
- 15:02Tom Scullion: It's on a treated material.
- 15:03Bernie Fette: You're just driving on the base material.
- 15:05Tom Scullion: That's right.
- 15:06Tom Scullion: That's
- 15:06Bernie Fette: Right.
- 15:07Bernie Fette: Okay.
- 15:07Bernie Fette: Okay.
- 15:07Tom Scullion: Bottom line on what we've been promoting is that we knew that our, our standard stabilizers cement wouldn't work because it kind of set up as fast.
- 15:16Tom Scullion: So what we've done in the last seven or eight years at least, is come up with a combination of cement in asphalt.
- 15:23Bernie Fette: Mm-hmm.
- 15:23Tom Scullion: , We have two products.
- 15:26Tom Scullion: One is 1% cement and foamed asphalt, and that's just another story in itself.
- 15:33Tom Scullion: Or we have 1% cement and an asphalt emulsion.
- 15:36Tom Scullion: We mix these two things together and we come up with the best of both worlds, I think.
- 15:42Tom Scullion: Okay.
- 15:43Tom Scullion: Because when we do this and we compact that thing, you gain strength, the asphalt will help you with the waterproofing because the last thing you want is to finish the construction and then you get three inches of rain that night.
- 15:56Tom Scullion: Right.
- 15:56Tom Scullion: And then you're putting these trucks onto it.
- 15:58Tom Scullion: So whatever you do has gotta have the strength and it's gotta have the ability to shed water if it gets rained on.
- 16:05Tom Scullion: The energy sector is still booming and it's still really, really booming in the Odessa area.
- 16:11Tom Scullion: And I think we put several hundred million worth of this material down in the last five years.
- 16:18Tom Scullion: They're rebuilding all the roads in Odessa, and this combination of fold EPP recycling with an asphalt cement combination is really working well for these people.
- 16:29Bernie Fette: So I'm hearing you talk about challenges that current modern road builders are having to deal with that were not an issue more than a century ago.
- 16:41Bernie Fette: Yeah, that's true.
- 16:42Bernie Fette: Okay.
- 16:43Bernie Fette: On the flip side of that, what sorts of things did the early road maintainers have to contend with that DOTs don't have to worry about today?
- 16:52Bernie Fette: What's the converse?
- 16:53Bernie Fette: And yeah.
- 16:54Bernie Fette: I'm thinking in part about horse manure as one example,.
- 17:00Bernie Fette: So what were the things from previous ages, early days of road building that we have today that they didn't have to contend with over a hundred years ago?
- 17:09Tom Scullion: Well, I, I'm thinking about the great advances that have been made, you know, okay, where, where, where, where are these things?
- 17:16Tom Scullion: And I, and I really think the advances have been made in the terms of the equipment that we have available now.
- 17:23Tom Scullion: I mean, this maybe is not known, but there's a lot of money in this road building and making sure it's permanent.
- 17:30Tom Scullion: Um,
- 17:30Bernie Fette: Great.
- 17:31Bernie Fette: Let's, let's talk a little about those advancements then.
- 17:33Bernie Fette: Yeah.
- 17:33Bernie Fette: Specifically in the time that this has been your life's work.
- 17:36Bernie Fette: Mm-hmm.
- 17:37Bernie Fette: , Can you start with talking a little about ground penetrating radar?
- 17:40Bernie Fette: Talk about that a little bit because just the name itself sounds pretty fascinating and then you can go from there.
- 17:46Tom Scullion: Yeah.
- 17:47Tom Scullion: I've been around this technology since the late eighties and I think I, the best way to explain it is to think that we're road doctors.
- 17:56Tom Scullion: What this technology does, if for a layman's point of view is X-ray the road, okay.
- 18:02Tom Scullion: We can go along at highway speed, use this technology to go and shoot into the pavement to tell us what we have there.
- 18:11Tom Scullion: And often we go to roadways and we really, like I say, it might be a 50 year old road and it's been maintained and there's all kinds of things going on.
- 18:20Tom Scullion: And then we put a very thin surface over it.
- 18:22Tom Scullion: So what's beneath the surfaces?
- 18:24Tom Scullion: We've got no clue.
- 18:26Tom Scullion: Right.
- 18:26Tom Scullion: So we needed a technology that would help us get through this whole process of rebuilding these roads, strengthen these roads.
- 18:33Tom Scullion: So before you do that, you say, well, what we got, well, we don't know what we've got.
- 18:38Tom Scullion: The last thing you wanna do is get a contractor out there to do a lot of repair work where he is gonna grind things up and hit a major change.
- 18:47Tom Scullion: You know, and the main benefits of this technology we're talking about, the ground penetrating radar is no surprises.
- 18:54Tom Scullion: Okay.
- 18:54Tom Scullion: We want to fully understand what we have beneath the surface so we can effectively treat it.
- 19:01Tom Scullion: The technology itself is very fascinating because it was developed by the U.
- 19:06Tom Scullion: S.
- 19:07Tom Scullion: military in the 1970s for land detection.
- 19:09Bernie Fette: To, to find landmines.
- 19:12Bernie Fette: Okay.
- 19:12Tom Scullion: Yeah.
- 19:12Tom Scullion: Now, back in the sixties and seventies, the landmines were all metal, but they changed from being metal in the eighties to be much smaller plastic mines.
- 19:24Tom Scullion: So the military decided that the technology, they developed a very good technology, wasn't appropriate for the application they needed, had to move on to something else.
- 19:33Tom Scullion: Mm-hmm.
- 19:33Tom Scullion: .
- 19:33Tom Scullion: So that technology was released for applications and that's where we jumped into it with a few small companies to say, well, what can we do with this stuff?
- 19:42Tom Scullion: Mm-hmm.
- 19:43Tom Scullion: , at the moment, we mount this radar antenna on front of a vehicle and it's four foot in front of the vehicle, and we travel down the road at 70 miles an hour and we can take a reading every foot as we go down and we can measure the thickness of the road and we can tell you if there's any defects in that road beneath the surface.
- 20:03Tom Scullion: We're looking down to about two foot beneath the surface.
- 20:06Tom Scullion: And so we essentially get an x-ray of the road at 70 miles an hour.
- 20:11Tom Scullion: Every one of these pavement rehabilitation strategies or projects I get involved with, we use this technology as step number one.
- 20:19Tom Scullion: We have a picture of what the animal is that we're trying to rehabilitate here.
- 20:24Bernie Fette: And having those readings is important because it's the quickest and most efficient way for you to find out what is happening below the surface.
- 20:34Bernie Fette: Yeah.
- 20:34Bernie Fette: This helps you and the contractors who are hired to fix the roadways helps to know exactly where the problems are so that you can Yeah.
- 20:44Bernie Fette: Put the dollars where they do the most good, right?
- 20:46Bernie Fette: Yes,
- 20:47Tom Scullion: Yes, that's right.
- 20:47Bernie Fette: That's right.
- 20:48Bernie Fette: Okay.
- 20:48Bernie Fette: Which leads me to the point that road building is a pretty expensive endeavor.
- 20:52Bernie Fette: Mm-hmm.
- 20:53Bernie Fette: .
- 20:53Bernie Fette: So can you talk a little about how all of these advancements, and I know we're talking about just one now, but just this one for example, how does it help to stretch transportation budgets, whether we're talking local or state or federal transportation budget levels?
- 21:08Tom Scullion: Yeah.
- 21:08Tom Scullion: I've been doing this stuff for a long time and I think in Texas we really have put together the set of tools that let you do it right.
- 21:17Tom Scullion: And it's not just us here at the Texas A&M Transportation Institute.
- 21:21Tom Scullion: The technologies we've been developed have been fully implemented statewide around the state of Texas.
- 21:27Tom Scullion: The main thing Bernie, is man, no surprises.
- 21:32Tom Scullion: Okay.
- 21:32Tom Scullion: We don't want to get into projects, start turning it over and find out.
- 21:36Tom Scullion: It's completely different from what we had.
- 21:39Tom Scullion: When you have these kind of surprises that you come to on projects, man that can eat your lunch, when it comes to getting these things done the way they should be done.
- 21:48Bernie Fette: I mentioned in that last question, something about the federal transportation dollars.
- 21:54Bernie Fette: Mm-hmm.
- 21:54Bernie Fette: and speaking of the federal level mm-hmm.
- 21:56Bernie Fette: Congress passed an ambitious piece of legislation.
- 22:00Bernie Fette: Yes.
- 22:00Bernie Fette: Last year, the Infrastructure Investment and Jobs Act.
- 22:03Bernie Fette: How does that collection of policies address roadway maintenance in this country?
- 22:10Tom Scullion: Yeah.
- 22:10Tom Scullion: We, we will have to see.
- 22:12Tom Scullion: The focus of that policy is really welcome.
- 22:15Tom Scullion: I mean, we really need to explain to the public that man, the, these roads were designed for 30 years and a lot of these roads out there and now 60 years old, they've lasted a lot longer.
- 22:28Tom Scullion: And they're held together with band-aids is what?
- 22:31Tom Scullion: What's happening without the emphasis put on it by this policy, you know that DOTs will never have enough money to do everything they need to do.
- 22:39Tom Scullion: So what they do with these older roads is they put band-aids on them, which means that they have to come back every three to five years instead of having them money to fix them properly.
- 22:49Tom Scullion: Right.
- 22:50Tom Scullion: So that's what you see a lot of, Bernie, going on there, is that you have a road that's cracked up.
- 22:56Tom Scullion: We go out and do the design and we give them two options.
- 22:59Tom Scullion: We say, well, if you want a bandaid to hold this thing together for four years, I can give you that.
- 23:05Tom Scullion: But if you really want to fix this thing for 20 years, you've gotta spend a lot more money.
- 23:10Tom Scullion: Well, that money was never available.
- 23:12Tom Scullion: Now the fact that the feds have come in there and you know, encouraged a thorough investigation that's really welcome.
- 23:19Tom Scullion: But whether we'll ever have enough money to do all the fixing that we need to do, that's another question.
- 23:24Bernie Fette: Because the, the roads we're talking about, they were definitely built to last, but they were not built to last forever.
- 23:30Tom Scullion: Well, just the length of time and the amount of traffic on them with the issues of the number of people coming to Texas, and then with the issues of the special development, energy sector development, agricultural development, and all this other things, the amount of traffic and the loads of traffic have all increased substantially.
- 23:48Tom Scullion: They were designed 30, 40 years ago.
- 23:51Tom Scullion: They were never in design for that level of traffic.
- 23:54Bernie Fette: So much of what we've touched on, we could do several hours of discussion on all of this.
- 24:00Bernie Fette: I know, Tom.
- 24:00Bernie Fette: So as I'm trying to wrap up our conversation, I'm, I'm wondering, can you share your thoughts on what you see as being the biggest research needs for the near future?
- 24:11Bernie Fette: We've talked a little about advancements over the past several decades.
- 24:14Bernie Fette: Where is the next big thing likely to come from?
- 24:18Tom Scullion: Of course, Bernie, the big thing for the next 10 years is gonna be this environmental stuff, this carbon footprint.
- 24:26Tom Scullion: How do we change our whole operation to give us a smaller carbon footprint?
- 24:32Tom Scullion: So the whole industry needs to look at this whole environmental side of things now.
- 24:39Tom Scullion: Mm-hmm.
- 24:39Tom Scullion: , I think just adding on to what we spoke about earlier, where we contribute on that area, there has to be worked on materials and whatever, but you think of the carbon footprint from rebuilding roads where you take everything away and build a new road to what I've been telling you earlier, which is recycling.
- 24:58Tom Scullion: Mm-hmm.
- 24:59Tom Scullion: , I think there's gonna be a big boom in this area of recycling.
- 25:03Tom Scullion: You know, when the road wears out, one of the things you can do is get rid of the whole road and then build a new one.
- 25:08Tom Scullion: Mm-hmm.
- 25:09Tom Scullion: .
- 25:09Tom Scullion: Well that takes a lot of energy.
- 25:11Tom Scullion: You've gotta know the materials, you've gotta take'em away.
- 25:14Tom Scullion: You've gotta bring new materials in, you've gotta mine them.
- 25:16Tom Scullion: Well, there's a lot of energy and a lot of cost there.
- 25:19Bernie Fette: And a lot of environmental implications.
- 25:22Tom Scullion: Yes.
- 25:22Tom Scullion: If you can do what I'm talking about, which is look at the existing roadway with the technologies we have.
- 25:27Tom Scullion: Look at ground penetrating radar, falling weight, deflectometer, and come up with a very good long-lasting design by grinding up what's there and treating it.
- 25:37Tom Scullion: Somehow the environmental impact is minimal compared with the full reconstruction process.
- 25:42Tom Scullion: So I think very, that's the focus and the future because of the federal push and you know, this is the global warming and all this kind of stuff going on here.
- 25:52Tom Scullion: It really is gonna come impact the road building industry.
- 25:56Bernie Fette: Lastly, Tom, what is it that keeps you showing up to work every day?
- 26:02Tom Scullion: Well, maybe I fooled a lot of people over the years, or sounding, but a lot of people think I know what I'm talking about.
- 26:08Tom Scullion: Maybe it's my funny accent.
- 26:10Tom Scullion: They told me that 50 years ago, Bernie, that this thing is gonna peter out.
- 26:14Tom Scullion: And I'm still here, man, and I'm still busier now than I was 50 years ago.
- 26:18Tom Scullion: I've got to the position where people trust me.
- 26:21Tom Scullion: Mm-hmm.
- 26:21Tom Scullion: , and whenever we have a problem, if something doesn't hold up, it was designed for 20 years and we're seeing problems in five years and we're seeing problems in two years.
- 26:32Tom Scullion: I get called in to do what's called forensic investigations.
- 26:36Tom Scullion: We did one just this week in the Odessa District, and these are the challenging things where roadways fail.
- 26:43Tom Scullion: If roadways never fail, you don't learn anything.
- 26:46Tom Scullion: But if a roadway is supposed to last 20 years and you have problems in one year, you go in and figure out what the heck happened here.
- 26:55Tom Scullion: Mm-hmm.
- 26:55Tom Scullion: .
- 26:55Tom Scullion: So I do about one of these a month, and that's truly where we learn things.
- 27:00Tom Scullion: If the road is designed for 20 years, you build in and it performs perfectly.
- 27:04Tom Scullion: You don't learn anything.
- 27:06Tom Scullion: A lot of the advances we've made in the last 15 years has been caused by digging into failures, understanding the failures, and implementing changes so it doesn't happen again.
- 27:19Tom Scullion: That's why I come to work, because I do a lot of these forensics, and when we do these forensics investigations, that's where we learn things.
- 27:28Bernie Fette: We've been visiting with Tom Scullion, a senior research engineer at tti, and by his own definition, one of the road doctors who is working to keep your daily travels is smooth and pothole free as possible.
- 27:44Bernie Fette: Tom, thanks very much for being with us.
- 27:46Bernie Fette: This has been fascinating.
- 27:48Tom Scullion: Alright, thank you Bernie.
- 27:50Bernie Fette: The process of building a roadway seems simple enough.
- 27:55Bernie Fette: Lay out the base material and cover it with asphalt.
- 27:58Bernie Fette: But keeping those pathways in good condition is far more complicated than it might appear.
- 28:05Bernie Fette: Maintaining a stable transportation infrastructure requires careful investment and scientific precision.
- 28:12Bernie Fette: Because the roads and bridges we drive upon every day were certainly built to last, but they were not built to last forever.
- 28:20Bernie Fette: Thanks for listening.
- 28:22Bernie Fette: Please take just a minute to give us a review, subscribe and share this episode, and we hope you'll join us again next time for a conversation with Tim Lomax.
- 28:33Bernie Fette: When Tim was a young boy, his mother told him to go out and play on a freeway.
- 28:38Bernie Fette: He used that advice to launch a 46-year career in transportation research thinking Transportation is a production of the Texas A&M Transportation Institute, a member of the Texas A&M University System.
- 28:53Bernie Fette: The show is edited and produced by Chris Pourteau.
- 28:57Bernie Fette: I'm your writer and host, Bernie Fette.
- 29:00Bernie Fette: Thanks again for listening.
- 29:02Bernie Fette: We'll see you next time.