Eight years old and full of wonderment, Ron Guntert Jr. crawled on top of a bulky slipform concrete paver for the first time on a project just outside of Gallup, N.M. For six hours on top of the machine, Guntert developed an appreciation for the ballet, then quickly found himself pondering the power of the rain dance.
“Every day about 3 p.m. a thunderstorm would roll in and it would rain so hard they would have to quit paving,” Guntert, who is now president of Guntert & Zimmerman, told ROADS & BRIDGES on the experience back in 1962. “The site was very close to a Navajo Indian reservation and my father used to always tell me when I was there that one of those medicine men or holy men of the Navajo tribe thought enough work was done for one day and called the rain to shut it down.”
The actual work was called a “ballet dance” by Ron Guntert Sr., who pulled his son around to various projects when he was at the head of the company, because when everything is in step it looks easy.
The concrete paving industry has taken significant strides over the past 10 years, but at times it has looked difficult.
“Concrete kind of went from the pavement of choice in the ’60s during the interstate highway system to where it was failing prematurely,” said Guntert Jr. “I think there has been more effort as an industry, the state side and the federal government side to emphasize better foundation for the concrete pavement, and that, coupled with improved quality, leads me to believe that concrete is on a resurgence.”
The Interlocking Concrete Pavement Institute (ICPI) thinks there are a lot of “believers” out there. According to a recent survey conducted by ICPI, sales of concrete pavers per manufacturer are on the rise for the third straight year. Sales per manufacturer in the U.S. exceeded 4.1 million sq ft in 1998 compared to 3.39 million in ’97 and 2.75 million in ’96. The typical U.S. firm experienced sales growth of over 22% in 1997 and 20% a year ago.
The Transportation Equity Act for the 21st Century also has the industry buzzing heading into the year 2000.
“The industry is very exciting nowadays because, along with everybody else, our business is good,” Carl Carper, vice president of worldwide sales and marketing for Gomaco, told ROADS & BRIDGES. “We obviously are enjoying the best years that we’ve had.”
And with a higher demand for smoothness and a quieter ride, customers are asking for the best pavers money can buy.
A dowel bar inserter, which eliminates faulting in the concrete, was an important industry first taken this decade, and computers are fueling the drive heading into the next millennium.
The use of Global Positioning Systems (GPS) and 3-D controls are on the horizon. GPS would keep the grade and steering control systems on the pavers at the proper position according to pre-mapped out coordinates, while 3-D controls follow a similar concept and would essentially eliminate the need of string or wire lines.
“Basically what is used there is a programmable computer that tells the machine what to do, so that’s going to save a ton of time,” said Carper.
A ton of experience
Gomaco claims it has put a lot of hours into its Commander III four-track concrete paver.
“This new generation of pavers is a culmination of years of experience all balled into one,” said Carper. “This machine is highly versatile and is designed to do a number of different things.”
Innovations included in the paver is a redesign of the hydraulic system. Every circuit has electronic-over-hydraulic control. A network controller and “smart cylinders” also are new additions. The network controller features an LED display, more memory, software and programming capacity, more computing power, additional processing speed and input and output capability, according to the Ida Grove, Iowa-based company. The network controller and smart cylinders now make it possible for push-button steering.
Track circuits have been redesigned, resulting in an increase in travel speeds. The paver can travel up to 97 ft per minute and can reach operating speeds of 44 ft per minute.
The ‘m’s’ in Miller
Putting up a barrier for Miller Formless Co., Inc., McHenry, Ill., is the M-8800. The machine is bi-directional and is designed specifically to slipform barrier and bridge parapet, according to the company. Standard dual augers and symmetrical design enable the machine to pour with the flow of traffic, and four tracks and ample weight give the machine stability for heavy-duty projects.
Powered by a 6-cylinder turbo diesel rated 145 hp at 2,000 rpm, the M-8800 slipforms pavement up to 20-ft wide in the straddle mode and paves up to 12 ft in the sidemount mode. Pavement with integral curb can be poured in both straddle and sidemount modes.
The paver features a maximum speed of 70 ft per minute.
The M-8100 comes from the same mold as the 8800. The machine can be used for barrier wall, bridge parapet, curb and gutter work, as well as straddle and sidemount paving.
A reverse direction auger is available for bi-directional pouring, and four tracks along with a five-point suspension add stability. The machine, driven by a 6-cylinder turbo diesel engine rated at 149 hp at 2,000 rpm, adjusts hydraulically for grade control and comes with carbide teeth for tough grades.
The M-1000 handles curb and gutter work and is equipped with a micro controller computer operating system. The model, which can reach speeds of 68 ft per minute, comes with a trimmer for simultaneous trimming and pouring, and can pour a 2-ft radius.
“We’ve improved the equipment already by the utilization of computerized equipment,” Kurt Jensen, sales rep for Miller-Formless Co., Inc, told ROADS & BRIDGES. “More manufacturers are using more sophisticated control systems to enhance the rideability of the pavement.”
RexCon, Milwaukee, handles highway and street work with Town & Country slipform pavers.
The Town & Country II has a maximum paving width of 37 1/2 ft and features hydraulically operated edge wings which adjust to maintain a straight edge. A positive no-drift crown control uses a jack screw system for crown adjustments, and the machine requires minimum clearance around obstacles.
Powered by a water-cooled 325-hp Caterpillar engine, the Town & Country II can pave at speeds of up to 45 ft per minute.
Telescoping auger strike-off assembly is a highlight of the Town & Country I paver. The feature allows both units to widen simultaneously for rapid width change. The auger is split down to 12 ft and each side is individually controlled. The model is also armed with a machine elevation system, one-point and two-point control, hydraulically-operated edge wings and positive no-drift crown. Driven by the same engine as the Town & Country II, the “original” paver has a tucking action tamper that prevents tears and provides more grout for a smooth, closed surface.
Guntert & Zimmerman, Ripon, Calif., has entered the Quadra era. The company’s S850 slipform paver includes a four-track Quadra feature that allows the transport of the machine at a width of under 12 ft.
The mid-sized paver’s “JC Extender” tractor frame extension system allows the tractor frame to telescope from 12 to 34 ft without having to disconnect a hydraulic hose or remove the crawler track endtrucks from the machine, and microprocessor-controlled steering and leveling systems allow for multiple steering modes, including 90 degree steering.
A front spreader plow spreads material in front of the paver, which is powered by a Caterpillar diesel engine that rates 250 hp at 2,200 rpm and can reach travel speeds of 70 ft per minute and working speeds of 15 ft per minute.
The 12-27SFP slipform paver from Allen Concrete Pavers, Paragould, Ark., can handle widths anywhere from 12 to 27 ft. The two-track crawler machine contains a Caterpillar turbo-charged diesel engine which rates 215 hp at 2,400 rpm. A hydraulic pump system and a hydraulically powered split tamper bar system are two additional features on the paver, which also comes with adjustable side forms.
Mobility must have been a No. 1 improvement priority at Bid-Well. Headquartered in Canton, S.D., the company has created its most mobile heavy-duty paver ever, the 6500, which features rubber tires instead of a track system, automatic skid steer for paving and automobile steering for on-the-job travel. The paver can travel on site without being towed.
The machine has automatic string line sensing control for elevation and steering, as well as a dual internal vibrator system.
The boom truss length is 30 ft and can be extended to 60 ft, with a truss depth of 48 in.
Two 58-hp diesel engines power the paver and paving carriage, which includes 6-ft long paving rollers and powered crown control. When using powered crown control, transitions can be adjusted hydraulically from the operator’s console without interupting the paving process.
Dual adjustable 10-in. diam. augers with double flighting strike off and meter the concrete forward on each paving carriage pass.
Power Curbers Inc., Salisbury, N.C., carries a team of four to handle flat paving up to 16 ft wide and highway safety barrier up to 6 ft tall.
The 5700-B can be used for slipforming curb and gutter and comes with hydraulic trimmer adjustment; the 8700 is a multi-purpose paver which features hydraulically adjustable side plates for paving depth variations up to 16 in. on-the-go; and the 150 and 440 XL are used for extruding concrete curb.