Asphalt Pro Features SB-3000 Job Story
Madden Puts SB-3000 to Work on Mill and Inlay
Source: Asphalt Pro Magazine
David Madden explained the crews must pave back what they’ve milled up by the end of the shift in Texas and Louisiana where Madden Contracting Company LLC, headquartered in Sibley, Louisiana, performs a substantial amount of mill-and-inlay work.
To get pavement prepped and all the tons down consistently, Madden himself has gotten creative and his crews have trialed a number of new machines over the years, including the SP-200 spray paver from Roadtec Inc., Chattanooga. With the launch of the new SB-3000 from Roadtec, Madden Contracting has continued its experimental spirit with positive results.
In 2019, Madden Contracting performed a 4-inch mill and inlay with a Superpave C mix, sealcoat and permeable friction course (PFC) on a section of U.S. 79 in Texas. The team was so pleased with the outcome, they submitted the project for a Texas Asphalt Paving Association (TXAPA) quality pavement award, which is now under review. This spring, the crew repeated the project on the next section of U.S. 79, using the SB-3000 in front of the paver.
“It’s an absolute mirror image,” Greg Greathouse said. He’s the roadway superintendent for Madden Contracting/Longview Asphalt Inc. and worked on both sections. “They tie into each other. Each job is about 5 miles long.”
It’s a two-lane road with 10-foot shoulders. “This road hasn’t been touched in a very long time. We did a level-up on the shoulders to make them a little bit safer, using a recycle and top soil mix.”
After the milling crew took out 4 inches, the Madden Contracting scissor-tailed broom cleaned the surface for paving. It’s a machine of their own making and it saves them time, effort and labor. “I would call it a game-changer,” Greathouse said.
David Madden designed and patented the scissor-tailed broom, which the crew brings to the jobsite on a lowboy, just like any other piece of equipment. Once at the site, crewmembers attach the broom to the milling machine, which tows it along. Its side brooms open into a V shape, similar to the tail of the scissor-tailed flycatcher. This lets the brooms direct material to the center of the lane for efficient pick-up onto a collecting conveyor, which carries material to the front of the milling operation.
“The cleaning zone is typically 1,500 feet behind the rotomill and is just the biggest headache there is,” Madden said. “Now, we tow the broom with the rotomill so it cleans with one pass and reduces the cleaning zone to 500 feet. Now my paving train starts 500 feet sooner. I pave an extra 300 tons a day by paving sooner. There’s no more haul truck taking the material away, no more power broom or operator, no more rotobroom, no more groundman directing that operation. Once we set it up, it’s autonomous.”
Once the cleaning zone was taken care of, Madden Contracting crews placed a 5/8-mm Superpave C mix in two 2-inch lifts on the mainline. The mill and inlay portion was 16,200 tons on both jobs, according to Greathouse.
A subcontractor took care of sealcoating all the way across, including the shoulders Madden had leveled up. “May first is the opening of sealcoating season here,” Greathouse said, so the subcontractor finished sealcoating the project May 7. He spoke proudly of the local crew, saying they did an excellent job for them. “On the current project, there was 51,300 gallons of AC20-5TR shot for the seal.”
Then Madden Contracting crews placed the PFC at 1.5 inches in June. They placed about 11,800 tons of PFC on both jobs. The asphalt mixes came out of Madden’s biggest plant, which was about a 50-minute haul from the project. The plant provided an average of about 2,200 tons per day for the project, but also supplied its regular customers.
“We own all our trucks,” Greathouse said. “I’ve got 28 trucks over here in Longview.” To manage trucking for the project, he looked at the work zone setup. “It was a flagging operation, so the trucks had to go through the flag twice; once on the way in and once going back. There was another route they could take to come in the back way and cut out one of those flaggers.” The software he uses to assist in planning is E-Routes.
Another strategy for increasing productivity was to devote his trucks to hot mix delivery and assign third-party trucks to the milling operation.
“I had 22 trucks of mine doing hot mix and third-party dumps for the millings,” Greathouse explained. By sending Madden trucks back to the plant with only one job—get loaded with mix to return to the site—Greathouse saved upwards of 60 to 90 minutes per day in loadout time.
The third-party trucks took care of millings only, developing a stockpile onsite, instead of trying to take a load of millings to the plant, dump it, clean out the bed, spray down, load out, and then return. Greathouse shared: “I was getting 1,800-2,000 tons a day before stockpiling. I started getting 2,200-2,400 tons a day once I started using a third party for the millings.”
The crew also used the new Shuttle Buggy on this project, and Greathouse noticed a number of benefits for the operators as well as for paving smoothness. The team has other Shuttle Buggies, so he was able to compare capacities.
“We think it holds more than the 2500,” Greathouse said. “When you dump the first load in the morning, it’s not overflowing.” He shared that his groundman dumped 95 trucks May 7 with the SB3000 on another project, but the team has put it through its paces since December 2019.
During a time when the districts in which Madden Contracting performs work were experiencing high numbers of COVID-19 cases, the company showed proactive caution having fatigued workers stay home until testing showed they were healthy and symptoms of fatigue passed. A worker who, thankfully, did not have the virus, was given time to gain full health while the crew adapted with new equipment.
“People that run Shuttle Buggies probably won’t believe it, but I ran a week while my dumpman was out sick,” Greathouse said. “The guy on top ran the SB-3000 and dumped the trucks all by himself all week. It is absolutely possible.”
Not all crews can adapt to a one-man material transfer operation, Greathouse said. For example, Madden Contracting requires one of the workers collect the tickets from each truck. For companies using e-ticketing, the new SB-3000 offers some new dumping protocol to think about.
Of course, having the dumpman on the ground makes an operation run more smoothly, and the engineers at Roadtec designed a safety feature into the new SB3000 for this worker. The grou
ndman’s operating station can swing into the envelope of the machine where the groundman has a platform to stand or sit while the machine travels forward, essentially taking this worker out of traffic.
The project on U.S. 79 has given Madden Contracting more than a nice project to submit for a TXAPA award. It’s given them a sense of pride in a job well done. Greathouse has received compliments from residents along the roadway and in the area who drive U.S. 79 every day. “All the people that live around there drive that first job everyday,” he said. “They say how excited they are that we’re fixing this next section.”
Using new machines or putting new concepts onto existing ones is part of the “fun” side of working at Madden Contracting. Greathouse spoke with pride about David Madden’s creativity when it comes to augmenting rotomills or building the solution to a challenge the crew might be having.
“We’ve got two side cutters that he added conveyors to so we can dump the millings outside the box. That really helps us when we’re doing widenings. David designed that.”
From the spray paver to the SB-3000, Madden Contracting likes to get into the new machines and give them a workout. “We like to play with things,” Greathouse laughed. “We have the first spray paver from 2015. We still have it to this day. On the first going, you get a lot of misses. On this one [SB3000], they didn’t miss much.”
With good equipment and an entrepreneurial spirit, the team at Madden Contracting paves a safe and smooth way for its neighbors.