As a contractor, making the initial investment in expensive technology can be a hard sell. You've heard the benefits, but you still can't justify the cost. Manufacturers however know their products and have designed these technology solutions to not only save you time, but also help you make more money.
Caterpillar Inc. recently conducted a production study at their proving grounds in Peoria, Il that once and for all put new technology to the test against traditional road building methods. They built identical roads side by side – one with integrated technology and one without – to measure differences in job time, man hours, machine hours and fuel burned. The goal was to give a visual demonstration to show how this technology can improve the workflow on the jobsite.
“We are always talking to our customers about the benefits of using these different technologies and there are always questions about payback,” says Karl Weiss, vice president of earthmoving at Caterpillar, Inc. “They want to know examples of where it’s been used, but those customers who have success with the technology don’t want to show that to their competitors.”
So Caterpillar took it upon themselves to prove it out with the intention of using the production study to educate their customers on what they can expect with these technologies, why they should be using it and where it can really take time out of the work load.
They constructed two identical roadways, 400-ft. each, and documented the process from start to finish. One roadway was constructed using traditional methods; stakes, stringlines and machines without telematics, and the other using Cat Connect technology and grade control.
“We didn’t know how it would go, how good it would be and how much improvement we would see,” Weiss says. “It surpassed our every expectation.”
During the initial layout of a job, a crew of workers set up stakes, calculates and publishes offsets and grades. This is very labor intensive and can take a good amount of time. On this 400 ft section of roadway, it took two hours.
Using Cat Connect technology and a drone to survey the site, you’re able to look at the layout and make calculations in a matter of minutes. There are no hubs or stakes, and plans are then automatically loaded in to the machines for work to begin. There are fewer people on the site, which helps to eliminate risk. This process took half the time than a traditional layout.
Earthmoving and grading can be the most labor intensive part of a project. You have to prepare subgrade, excavation, embankment delivery and compaction. During a traditional roadbuilding process, there are a lot of people doing the work in close proximity to equipment. Workers also tend to sit idle for continued grade checking and verification. These checks are manual processes that can miss production targets while creating substantial amounts of rework.
Then during grading, workers are spreading and finishing the grading of an aggregate base. Measurements during this process can identify inaccuracies. This can lead to time and cost over runs. Having too much material means additional passes, higher fuel consumption. Having too little material leads to more trucking hours, higher unit costs.
The entire earthmoving and layout phase using traditional methods took 24 hours on this quarter-mile project. If you compare that to the technology construction, you can easily see how this is where contractors can make their biggest gains.
“The heart of the success of the road building activity is the 2D and 3D grade control systems,” Weiss says. “We used a Universal Total Station (UTS) on the site and then we put GPS on all the machines that had a blade on them. Some machines had 2D grade control and some had 3D grade control.”
Weiss said that one of the key elements that helped half the grading time was Slope Assist. Even if the unit was not equipped with a GPS receiver, the machine has the 2D capability to help maintain specifications.
“If you tell the dozer you want a certain side slope or grade, you can put those limits into the machine and it will set that off of the tracks. If you have a flat surface, you can build in your slope and grade without a 3D system.”
In cab displays provide machine control and guidance, progress at a glance and allow grade and compaction to be checked from the cab. Not only does this keep your operators safe and less fatigued, but it also means that operators of any skill level can work efficiently on these jobsites.
Using that machine control and guidance along with intelligent compaction (IC) replaced manual processes to eliminate delays and ensure jobsite specifications were met. Excavation cuts and fills achieve elevation tolerances and density targets in the fewest number of passes.
Truck payloads can be reduced as well with wheel loader and articulated truck payload systems. These payload systems ensure accurate delivery and quantities of material to the jobsite saving time, fuel and money.
“The 3D plan that was built and loaded in to the system allowed us to know the amount of aggregate and dirt that we needed to bring in,” Weiss says. “Accurate material delivery and installation allowed us to avoid extra grading and compaction and we didn’t need to bring in surveyors to look over the project with stakes and string.”
During soil compaction, the machines were equipped with IC. These machines can sense through rolling resistance how compacted the material is.
“For quality reasons, there are usually inspectors on road sites to ensure compaction,” Weiss says. “They only can check in certain areas and not the entire roadways which is why sometimes we get potholes.
“With IC, the machine tells the operator where compaction has already met specifications. This saves in the number of passes and operator makes, but more importantly, we know he went over every piece of the road and it was compacted to the right level.”
The earthmoving and grading portion of the road on technology construction section took a total of 12 hours. Half the time it took on the traditional build.
When you’re ready to pave on any job, you traditionally have to verify both the elevation and the compaction before laying down asphalt. Paving hubs are set up and stringlines are then installed to guide the pavers. It took the crew four hours on the traditional build to complete paving.
During the technology build, you’ve already verified the grades and compaction, so redundant tests do not need to be completed. The pavers were set up with UTS grade control which eliminated the need to set up stringlines. This led to a greater level of efficiency in both time and in materials.
“One of the advantages, not just on time but on material savings, is that we we're able to keep a much tighter tolerance on the asphalt thickness throughout the duration of the paving process as the paver was using a UTS system to follow the grade and design,” Weiss says. “As we had the grader come in and do the finished grade, we had a high confidence in the consistency of the material laid so we could really keep it very close and not over-pave the asphalt. A lot of times that happens when there is an uneven roadbed. You have to pave more asphalt to make up for the mistakes that may have been made during the finish grading of the base.
“Between the UTS on the grader, the intelligent compaction and then using the UTS on the paver, we’re able to eliminate material overruns. The paver already knows the depth we want to pave to and it adjusts the screed automatically.”
The theoretical quantity of hot mix asphalt (HMA) was 192 tons. On the traditional build, the crew laid down 211 tons of asphalt for the 400-ft. section. On the technology construction, just 194 tons were laid. This is attributed to the fact that the crew was able to control the flow of materials that much more efficiently. Not only does that cut back on your production costs, it cuts back on trucking times, fuel and manpower.
The total roadbuilding time for the traditional build was 29.5 hours, compared to the 16.10 hours it took on the technology build.
“When you show contractors the video, they can immediately see where you’re saving time.” Weiss says. “They know how to build a road and they immediately understand why these processes are saving them time.
“It’s not just the fuel savings or the dollars you save on that project, the primary benefit is really in them getting it done faster. This is going to allow contractors to get more business. If they get it done in half the time, they can go out, bid more work and get that crew on more territory to grow their business.”
Weiss also says that DOT’s need to begin supporting these technologies. “They need to understand and support this because it can get their money to go further,” he says. “Getting roads done faster means that their constituents can drive down the road and not have road construction.”
Taking the First Step
Still, with all the benefits laid out in front of them, contractors may not want to invest the $250,000, which is what was invested on this project, but they can take small steps to get there.
“The majority of customers are not using these technologies at all,” Weiss says. “Those that are, have a mix of machines that have it and some that don’t, so they’ll see a portion of these improvements. However, we’re still not seeing fast enough adoption rates. We want our customers to get these productivity improvements.”
Weiss says this is why the company developed Slope Assist. “It gives customers an easy step in to this kind of technology,” he says. “You don’t need a GPS receiver, you have the grade control technology built in to the machine. You can tell the machine your slope and grade and the machine will help the operator automatically fit that profile.”
Weiss recommends buying a machine with these types of technologies already installed to immediately start seeing advantages.
“There a lot of basic technologies that we’ve developed that don’t require a field investment,” Weiss says. “However, they allow a customer to familiarize themselves with the system and if they like it, they can upgrade to the full 3D system and build upon the unit they already bought. We regularly hear that any customer who has made an investment in technology receives a payback on it in under a year,” he finishes.
In fact, the production study showed that a contractor who invested the $250,000 in technology that was done on this section of roadway, would only need to construct five total miles of road before the technology would not only have paid for itself, but actually start to make a profit.
The Numbers Tell the Story
From start to finish, the technology improved the road building process substantially. The process required less time and used less resources.
31% fewer man hours
· Better resource allocation
· Less exposure to risk
· Solution to skilled labor shortage
34% fewer equipment hours
· Lower maintenance and repair costs
· Increased machine availability
· Extended machine life cycles
· Effective utilization and resale value
46% fewer project hours
· Lower unit costs
· More profit
· Increased opportunities to bid more jobs, more jobs equal more money
37% less fuel consumption
· Another way to lower operating costs increase profits and machine life
· Secure competitive bid advantage
· Reduce emission levels and carbon footprint
On the Job
The machines that completed the job were the same for both sections of road built. One set of machines were equipped with Cat Connect telematics for the technology construction. The Cat machines used on both the Traditional & Technology Connected Roads:
140M3 M Series 3 Motor Grader
745C Articulated Truck
Also used were three competitive machines on this project* – an important factor to note, because Caterpillar, Inc attempted to replicate an authentic worksite in order to show the benefits of technology. The reality is that a vast majority of today's job sites contain mixed fleets. In most cases, no one brand is exclusive to the customer or the job site. Because of this reality for most customers, Cat Connect technology is designed to be utilized on mixed fleet operations. And, regardless of make or model, the technology improves the use of any machine.
*In one case, an equivalent competitor machine was not available. To accommodate, Caterpillar replaced with a smaller Caterpillar machine on the technology connected road.
The Bigger Sustainability Picture
While saving time and money is one great advantage for the contractor, saving the environment is really the end goal and where the industry is heading. The potential reduction in a contractor’s carbon footprint was made very clear through this production study.
“After we did this job, it really struck home when one of the folks told me that we saved 12 acres of forest land,” Weiss said. “Just on that 400-ft road, which is not very far, we reduced the amount of carbon put in the air to the equivalent of what 12 acres of forest sequesters over a full year. For just 400-ft. of road. That really explains the impact of not just fuel efficiency, which we’re working on with every machine, but by getting the job done in half the time, we stopped those machines operating for the rest of the time which stopped that carbon from going in to the air.
“When you multiply that out and realize that these jobs can be done with efficient machines and technology that allow the work to be done faster, we will be putting less carbon in the air and boy we can really have an impact on the environment. It’s just a win-win-win.”