Ep. 97: Go Stringless - Advances in Concrete Paving with Wirtgen America

While slipform pavers have been around for a long time, many contractors still hand form concrete pavements and sections. Wade Bowman, national sales manager, Wirtgen America, joins CONEXPO-CON/AGG Radio to talk about the benefits that slipforming can provide and the challenges contractors face. He also dives into the topic of stringless paving and discusses if its time has come, identifying how a contractor can ensure success with stringless.

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Show Transcript:

Intro: Welcome to CONEXPO-CON/AGG Radio, brought to you by the Association of Equipment Manufacturers with your host, Peggy Smedley.

Peggy Smedley: This is CONEXPO-CON/AGG Radio, brought to you by the Association of Equipment Manufacturers. I'm your host, Peggy Smedley. For this podcast we will be diving into the topic of slipform paving. Slipform pavers have been around since the 1940s and they're used in a wide range of different vertical structures such as towers, bridge columns, and even offshore platforms. In addition, slipforming is used for straight vertical concrete structures but also where the wall thickness has changed. But it's not surprising today, many contractors still had form concrete pavement in sections.

Peggy Smedley: On this episode we will identify the benefits of slipform paving. We will also discuss, as contractors, how you can ensure a smooth pour for projects. Then we will dive into the topic of stringless paving. We will discuss through a combination of 3D and position technology how you can remove the stringlines. As a result, you can improve productivity and quality on paving projects while they are on the job. But the real question that needs to be asked and even answered is whether now is the right time to implement stringless paving.

Peggy Smedley: As always, we are joined by a great guest and someone who can help us answer some of the most challenging questions. Please join me in welcoming Wade Bowman, national sales manager of Wirtgen America.

Wade Bowman: Good morning. Thanks for having me, great to be here.

Peggy Smedley: Wade, it's really kind of interesting that you guys are doing a lot and slipforming, as I mentioned in the opening, has been around since the 1940s. But many contractors are still kind of doing things in hand forming concrete pavements. I did some research and this is all interesting to me because in the research I found out is there's a lot of benefits to slipform over hand forming. And I'd love for you to tell our listeners really what are they and I think you're the expert way more than I am to kind of walk us through that.

Wade Bowman: Well certainly. Thank you. The advantages boil down to a couple of things, one is speed. Obviously with a machine, if a job site is set up properly, a machine can put out a lot more production than a hand crew can that's trying to set forms. So if a contractor is in the business to make more money, and who isn't, then using a machine is the way to go.

Wade Bowman: Secondly, the product that a slipform machine can put out is much more consistent and durable than what can be done by hand. And the reason for that is that a machine can consistently vibrate and place the concrete such as the product is more dense throughout and more consistent. No honeycombs, and the vibration is properly done throughout the section.

Peggy Smedley: Now this is interesting to me because this is probably the first time that I've ever heard someone say, "Machines do something better than the individual." So in the construction world, how did we actually get contractors to say, "I really want a machine to do something and not the human." How did you get them to really say, "This is the way to go."

Wade Bowman: Well, a good analysis make it pretty clear to the contractors in most areas. Of course, it's not for everyone if someone's got work that's extremely chopped up and comes in small drips and drabs, maybe that still makes sense to do that by hand. But it's kind of like working in your garden. If you're going to plant a few tomato plants, a shovel is fine, you can do that by hand. But if you're going to excavate for a large building, you don't really want to do that with a shovel. And the same could be extended to the notion of slipforming. If a project is maybe 100 feet of sidewalk and it's broken up with trees and fire hydrants and things like that, okay find, do it by hand and with forms. But if a contractors got, say a mile of curb and gutter or a barrier to do, machine is clear choice in most cases.

Peggy Smedley: Talk me through some of the challenges because I have to think for slipform contractors, they've had to go through a lot of challenges over the years since we're talking about something that's been worked on for decades and the technology has had to change as well.

Wade Bowman: Sure, sure. Well early on, the contractors were working with machines that probably weren't as reliable as they are now and didn't have the same level of sophistication. So nursing those machines from way back in those days would have been more difficult. But today's machines are a lot more reliable and a lot more accurate so that only helps the contractor to put down the work quickly and accurately and make more money.

Peggy Smedley: So when you talk about that profitability and making more money, how do you actually do that? How are you maximizing the ability to make more money? I assume were talking about time and accuracy and the speed of things. But walk us through that when we talk about what you were saying that the machines weren't as reliable back then to what we’re talking about today versus a few decades ago.

Wade Bowman: Well as far as profitability, of course, versus hand forming, the number of lineal feet or squares put down by a machine can greatly exceed what can be done by hand. So that's part of the profitability. And if we look at the, say for a paving contractor, course with slipforming machine can be anything from a curb and gutter machine all the way up to a highway class paver. If we're looking at, for instance, a highway paving contractor, not only are the linear feet important, the amount of production, but also the ride. And these days in particular, the ride bonus or lake thereof can make or break a contractor on a big job. If the machine is not putting down the product accurately and achieving good ride, that contractor will likely have to go back and grind, which costs money, and it will likely forego the ride bonus. And that can put that job in the red as opposed to being profitable.

Peggy Smedley: And when you talk about that, are we talking about now the ability to, these large amounts that you're talking about and getting the ride in the process and the form and the geometric shape of the finish, makes a big difference that you're doing with all this as you're describing here, right?

Wade Bowman: Yes, yes. As far as geometric shapes, of course for a paving contractor, putting on a slab but these machines can also put down barriers, curb and gutter, sidewalk, shoulders of course too.

Peggy Smedley: One of the things I mentioned in my opening was actually now the idea of stringless paving. Has that time now come? Are we seeing a change, is there an evolution now starting to occur from one way of doing things to another?

Wade Bowman: Well there sure is. For many contractors, stringless paving is already here and some of them have been doing it for quite a long time. The first stringless paving took place way back in 1997 when we put a stringless setup on one of our machines for a railway project in Germany. But it has been a bit of an evolution, it's been gradual over the recent years. But I think, from what I can see, that the process of switching to stringless is actually accelerating to the point where, I would say, 10 years from now, using string line will be the exception rather than the rule.

Peggy Smedley: And the reason you're saying that, because right now, I think if you would say, it's fairly expensive right? I mean it's not an inexpensive process compared to some other things that you could be doing. I mean, is it going to eventually pay for itself or what's that process as were looking at it?

Wade Bowman: Well that's a very good point because it is very expensive even when compared to the cost of the slipform machine itself, the stringless setups are very significant. And so that upfront expense is much, much greater than it would be for a string line setup. But the payoff is that in going to stringless, first off, the contractor does not have to buy and lug around all the string line components, does not have to place the string line on the job. The placement of the string line is something really, quite frankly, not many people really want to do anymore.

Wade Bowman: And in addition to that, once the string line is set up, it constricts the flow of material and equipment and personnel around the job site. So it constricts that flow and can also be a bit of a hazard with all those stakes sticking up and the potential for tripping over the string line. So there's that part of it but that's kind of the obvious part. But then as we look at job sites, they're evolving, there are more and more stringless job sites now than there were in the past. So in many cases, if a slipform contractor wants to put up string, he'll have to pay to have hubs put in because they wouldn't be there because the job site to that point has been stringless. So that's an extra expense to have those hubs put in and, of course, that can be foregone if we continue with slipform in the stringless mode as well.

Peggy Smedley: So when we’re talking about remove string lines and pins from a job site, were actually increasing some of the safety it sounds like what you're describing there.

Wade Bowman: Oh, absolutely. Absolutely, yeah. Rarely does a day go by where someone doesn't trip over a string line. Usually that doesn't put somebody in harm’s way but it can if someone trips and falls right in front of the machine. Or if someone is getting off the machine and falls, those stakes are there and falling on one of those is catastrophic. So it's much better to get those off the job site and out of the way.

Peggy Smedley: So if I'm hearing you correctly, we're reducing the injury, then we're eliminating kind of the survey setup and error that you just described. But now you're increasing productivity, it sounds like, the quality performance. There's a lot of things that are going on when we’re doing this. And then what you said earlier, it's kind of reducing over trimming and over pouring based and what you were just describing. Is that correct?

Wade Bowman: Surely. If the job is stringless from the bottom up, that's very efficient. And, quite frankly, a slipform machine can and does anticipate what's coming up in the stringless file as it goes along, as opposed to just reacting to a deflection of the wand on a string line sensor. So, yes, it can be much more accurate than a job done on string line.

Peggy Smedley: So is there a better way for contractors to actually ensure greater success as they go to stringless right now? I mean, because as they make that transition or they say, "I want to make the move." Is there one way to say we can experience all the success that we've described here?

Wade Bowman: Well, of course there're no guarantees but the first thing to do is to make a detailed analysis of the pros and cons for a given market because there are a lot of differences from one market to another, especially when we look at labor costs. Another thing to make sure of is to find the right system. There are a good handful of stringless systems out there and choosing the right one is critical, of course.

Wade Bowman: And then also the contractors got to make sure that the right staff is in place. To succeed at this, the personnel mix might need to change. Instead of having that crew that puts up the string line and is very good at that, and some crews are really fantastic in how they do that. The contractor now needs a group of people who are comfortable in a stringless environment, basically a surveying environment. And so that usually requires people with surveying experience or at least people who thoroughly understand that environment.

Wade Bowman: And then finally, there's got to be buy-in throughout the organization from top to bottom because making the change from string to stringless is challenging. And a contractor shouldn't look at that as if he's just putting a CD into a CD player and away it goes because there's more to it than that.

Peggy Smedley: Has there been a lot of hurdles when you look at this? I mean companies really need to look at this seriously and say, "If you don't do it right, you're going to stumble." That's what it sounds like. If you really don't take the right precautions, you can make this a lot harder for yourself as a contractor.

Wade Bowman: For sure, for sure. Preparation, as with any type of construction project, preparation is key and the stringless is no exception there. So the better everyone is prepared to work on that job and running through the files to make sure there are no busts in the file and also checking as builds as the machine goes along, is critical. Because there's no string line to visually check again so without as build checks, it can get very expensive if there are mistakes made and they're not caught quickly.

Peggy Smedley: Talk to me a little bit about your company right now because you guys are new to the American slipform market. Tell me a little bit about that comparatively and what you guys are doing. I also think that you're a John Deere company now, correct?

Wade Bowman: Yes, yes we are a John Deere company now and we're very excited about that. As far as the slipform market, as you know, you probably know Wirtgen has been in the American market for quite a long time. And we have a very prominent position in milling machines and other products in our group, the Hamm rollers, the VÖGELE asphalt pavers, Kleemann crushers and so on. But we've also been active in slipform for a very long time too, since the late 80s.

Wade Bowman: However, that activity has been limited to international markets and the main reason for that, well two reasons. First, is the American market, or the North American market in general, is very different from most of the international markets in that we require much more robust machine to achieve higher production rates. The American market of course is hyper competitive in everything we do here and construction, and especially slipform, is no exception to that. So the machines had to be re-engineered and the horsepower, in most cases, has been increased substantially. And a good time to do that was with the introduction tier IVs.

Wade Bowman: So the decision was made to bring in the machines at that point, and we first introduced slipform machine in 2010. It happened to be a curb machine and that was not the best time to introduce a curb machine to the North American market because of what was going on with housing at the time. But that as it was, that decision was made a few years before. So we came in with that curb machine and then we introduced, a year later, a multipurpose machine. And we've gotten to the point now where we have an almost complete lineup with our big pavers in the market as well.

Peggy Smedley: So when you look at that, so with looking at Wirtgen and the slipform bring to the market, do you think that you'll be able to lead from you knowledge that you have from a global perspective, helping with the U.S kind of needs right now with the changing market, there's a lot of changing tech side. Idea, what I mentioned earlier, getting contractors to understand the benefits of working with machines, understand working side by side with them and understanding the benefits and the efficiency, the safety. There's a lot things that you're bringing that they can understand. Has there been a lot of that upside in education coming into it?

Wade Bowman: Yes, and that's been very exciting. We, on the slipform side with Wirtgen, have faced a lot of different challenges throughout the world. So we're accustomed to encountering any level of customer, those who are brand new to slipform and those who've been at it a long time. So it's been fun to educate them to what we bring to the market and we've encountered a lot of different, like I said, lot of different challenges worldwide. We sell roughly 400 slipform machines a year which makes us by far the world leader by market share and volume. And so we've seen everything from curb and gutter to barriers to very interesting oddball projects and, of course, paving as well.

Peggy Smedley: So help me understand then Wade, what does the future look like then for construction and even regulation? Because I think regulation is going to play a role in what happens. Do you think a lot about that because I imagine it's got to be different what happens in other parts of the world than what happens in the U.S. Do you have to kind of manage that a little bit?

Wade Bowman: As far as regulation goes, probably the biggest, of course safety is always a concern. Our engineers, we've got a very strong safety department, they look at and work with the governing authorities to make sure we comply with all necessary standards. As far as regulation goes to, of course the emissions regulations have changed a fair amount over the last few years and they're changing again in Europe as they go to Euro five, which is even more stringent than tier four final. So that can be challenging because those requirements have to be met and then the requirements for North America need to meet and those are much more stringent than other parts of the world, other parts of even, say, Eastern Europe and Asia and Africa and South America.

Peggy Smedley: So just in general, is there kind of some trends that you see that are coming in general in the concrete industry, slipform industry, that you're thinking in general that you have to think about just in that it's coming?

Wade Bowman: Well in addition to stringless, and we talked a bit about that, that's a big trend that's continuing, rarely do we talk to anyone where stringless doesn't come up. But also, I think the market will continue to become more competitive, if you can imagine that. As contractors look for the edge to put down whether it's curb and gutter or barrier, put it down where it's supposed to be with minimal work behind the machine or whether it's a paving machine, achieving maximum ride bonus. I think that the trend will be towards greater utilization, attempts to put less effort into mobilizing and demobilizing machines on and off of job sites and getting the work done quickly and hyper-accurately and getting in and out. Because jobs seem to be more and more to be cut up and staging of the jobs does not allow for a contractor to put a machine on site and just run it for miles and miles and miles and finish that job.

Peggy Smedley: Is the internet of things and emerging technologies starting to play a role in capturing data in how those machines are operating?

Wade Bowman: Oh that's a good point too. Definitely the more information that is captured, the better. And that's a trend too, you make a good point, I hadn't mentioned that. That the capture machine data and to feed that back and forth. So that, one, if there's an update needed, say a software update, we can try that, push that out. And vice versa, if we can remind a customer maybe that maintenance is due or if they have a fault to work with the directly and through automation rather the old fashion way over the phone.

Peggy Smedley: Well, I have to tell you Wade, this has been a great conversation. Thank you for your time. Wade Bowman, National Sales Manager of Wirtgen America.

Wade Bowman: It was my pleasure, thanks for having me.

Peggy Smedley: Alright, we appreciate. So hopefully we've given you all some great insights into slipform and stringless paving and now you can kind of ensure some success, I think for your company in the future. I certainly learned a lot. And thank you all for joining us today for our show.

Peggy Smedley: That's all the time we have for today. I hope you'll join us next time. CONEXPO-CON/AGG Radio is brought to you by the Association of Equipment Manufacturers. Stay up to date on the technologies and trends impacting the construction industry by subscribing to our 365 e-newsletter. And you can do that by visiting conexpoconagg.com/subscribe. Thank you for tuning in to CONEXPO-CON/AGG Radio brought to you by the Association of Equipment Manufacturers.

To see the latest advances in concrete paving products from Wirtgen America and other leading equipment manufacturers, attend North America's largest construction trade show, CONEXPO-CON/AGG. The next show will be held March 10-14, 2020 in Las Vegas. Learn more about the show. 

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