No, it’s not another Elvis sighting in Australia. The King of Rock and Roll has not returned from the dead. This Elvis is a GOMACO Commander III that is slipforming to an audience of over 100,000 cattle and sheep on the 16,000 acre Yambinya Feedlot Tasman Group Services in Burraboi, New South Wales, Australia. Elvis, the Commander III, earned its nickname from its slipforming crew because, according to them, it rocks.
DMC Concrete Developments, based out of Melbourne, bought their Commander III after seeing one at work in a television documentary. They found the idea intriguing and researched slipform pavers in general before deciding on the Commander III.
“I saw this on TV and it blew me away seeing what could be done with these machines,” Dom Cimino, Director of DMC Concrete, said. “I knew we could apply it to our business, so we did our research and we found the right company with the right equipment. The Commander III is the perfect machine for our workload. We call the machine Elvis, because it rocks all day long!”
DMC Concrete specializes in concrete buildings, factories, concrete panels and feed bunk. They put their new machine to work on the massive project at the Yambinya Feedlot. By the time they complete the project next year, they’ll have slipformed approximately 15 km (9.3 mi) of both flat slab and feed bunk, and 13 km (8.1 mi) of six meter (19.7 ft) wide roadway. All of the work is carried out within the extreme conditions of the feedlot.
“We do a lot of feedlot work, but this project is the first time for us slipforming in this large of a scale,” Cimino explained. “It wouldn’t have been possible without my partner, Sam Barbirotto. Sam has taken this project on and is making it a success.”
The Commander III’s first application on the feedlot was a nine meter (29.5 ft) wide, 150 mm (5.9 in) flat slab. On one side of the slab, feed trucks drive along and pour feed into the bunks. On the other side of the slab, cattle stand and feed on the clean surface of the concrete.
The slab is slipformed on a laser cut and graded sand and limestone subgrade. DMC’s own concrete trucks deliver 6 m3 (7.8 yd3) loads of concrete to the paver and dump right on the grade. Their batch plant is located on site and is capable of producing 250 m3 (327 yd3) of concrete per day, which limited their daily slipforming production. Slump averaged 70 mm (2.75 in).
The heat and feedlot conditions created additional challenges to the mix design.
“The heat was unbearable and the mix design would change up to six times a day because of extreme conditions,” Cimino said. “We also were adding an air mixture that was needed for durability. The additive keeps the concrete from absorbing the cattle’s urine and helps cut down on the feedlot smell. It also stops the urine from eating into the concrete, which reduces the chance of disease for the cattle.”
The slabs were given a roller dimple finish to help create traction and grip for the cattle. The finish is applied behind the paver by a worker who used a roller with the dimpled pattern on the freshly slipformed concrete. Joints were hand cut into the slab every six meters (19.7 ft).
With the concrete flat slabs finished, work could begin on the feed bunk portion of the project. The profile was a challenging one.
The base of the feed bunk is 1000 mm (39.4 in) wide with one side wall 650 mm (25.6 in) tall and the other 550 mm (21.7 in) tall. The sidewalls are both 175 mm (6.9 in) wide. The right sidewall also has to be able to withstand the insertion of a pole that eventually helps form a fence across the top half of the feed bunk.
The feed bunk mold was built with a specially designed hydraulic pole inserter that allowed on-the-go bar placing. The inserter features a carriage mechanism that allowed the inserter to be able to move backwards in relation to the forward travel of the Commander III. This allowed the machine to be moving forward, even when inserting a pole and not causing any damage to the side of the bunk because of the forward movement of the Commander III.
The 1.3 meters (4.3 ft) long by 75 mm (3 in) diameter poles were inserted 450 mm (17.7 in) down inside the sidewall. They are placed at three meter (9.8 ft) intervals. Joints are hand cut every three meters (9.8 ft).
“The most challenging aspect of the feed bunk was just getting the right mix design for the machine,” Cimino explained. “We added a lot of air and plasticizer which made the slipforming run smooth and the end result was a smooth finish.”
DMC was confident their Commander III could handle the feed bunk challenge. They didn’t even attempt a test pour, they just put the machine on line and started slipforming.
“We just went for it,” Cimino said. “The feed bunk looked great and we had very little touch up work, and that was just around the posts. This Commander III unit never missed a beat under these extreme conditions and that’s considering everything else on the farm breaks down from the heat.”
Production is averaging 385 meters (1263 ft) per day with their best days reaching 450 meters (1476 ft). The biggest trick is keeping the slump of the concrete constant. DMC likes to keep their concrete slump for the feed bunk at 20 mm (0.79 in).
The project’s remote location also made it necessary to have their own plant at the feedlot. An on-site plant also gives DMC the ability to constantly monitor the quality and slump of their concrete, even with the changing temperatures.
“It would have been so much simpler if we didn’t have to worry about the supply of concrete, but in the middle of nowhere, you have no choice,” Cimino said. “We are bringing in water, aggregate and cement all of the time and we constantly have to test our concrete. Setting up our own concrete plant with six concrete trucks has been extreme.
“But it also gives us the ability to tweak the concrete to suit. We have slipformed in 50ºC (122ºF) weather and the machine never faulted. If you get the mix right, the machine rocks day and night.”
The third application the Commander III will be slipforming within the Yambinya Feedlot is a new, private ranch road approximately 13 km (8.1 mi) long. The road will be six meters (19.7 ft) wide, 200 mm (7.9 in) thick and will be slipformed in two paving passes.
DMC Concrete has been at work on the feedlot for the last two years. Cimino figures they have another year of work there before they are completely finished with all facets of the project. The Commander III has been there for the last year and has been working exceptionally well for the company.
“We are a very, very happy customer,” Cimino said. “This machine advanced me to another level in my work. My guys get so tired doing really nothing most of the day but watching it work. The machine just rocks all day.”