Slipform pavers are versatile enough that they are used for just about any paving job these days. With the diversity of sizes and the availability of kits and molds that change the abilities of a particular paver, you can do everything from curb and gutter to guardrails, barriers and multi-lane highways - sometimes all with the same machine.
?There are so many contractors who do so many different jobs with their machines,? says Tom Devonshire, Terex Roadbuilding. ?For example, a mid-range, four-track paver such as the 3504 can be converted to do 12- to 36-ft. paving widths. It can also be fitted with barrier molds. It?s all in the utilization of the equipment.?
Versatility certainly enhances today?s machines. Kent Godbersen, vice president of worldwide sales and marketing, GOMACO, notes that GOMACO units feature pivoting legs for variable track placement, enabling them to adjust to varying jobsite conditions and easing transport. And for easy, accurate bar placement, insertion bar system options range from those with hydraulic cylinders to air- or manually-powered units. The systems can also be frame mounted, side mounted or inserted with a trailing form. The In-The-Pan Dowel Bar Inserter (IDBI) fits within the length of the paver - it doesn?t require massive rear extensions to the paver frame.
Frames that widen hydraulically make width changes easier. For example, GOMACO?s dual telescoping V2 variable-width mold will make on-the-go width changes for tapered slabs.
Terex?s Series 6 slipform paving kit eliminates conventional nut-and-bolt connections by utilizing a wedge and pin locking system. Widths can be changed relatively quickly, allowing the paver to ready to work in hours rather than days.
According to Devonshire, time was of the essence on a Texas job last summer, which was delayed more than 30 days because of rains that flooded many cities around the Dallas jobsite. A big concern for the contractor was reducing paving time while still meeting tough ride specs.
The Series 6 paving kit helped save time because it could be used to do all of the mainline paving, which required paving at three different widths. By using the kit, the contractor estimates he saved 2.5 days.
No easy answers
With various sizes of machines offered, as well as options, sorting out which machine is the best choice for which job isn?t always easy. ?There are no simple answers,? Devonshire says, noting that when combined with the number of tractors available, the page count for listed options of Terex machines nears triple digits. ?You will always have a basic machine configuration. But contractors don?t buy a paver off the shelf. There is always something unique about every project.?
The selection process requires knowing what the immediate and future project requirements involve, notes Godbersen. He recommends asking yourself questions such as: Are there tight clearances involved? Are width changes required? If so, how easy is it to change the paver width? Does the paver have hydraulic frame widening to help accomplish width changes? What is the required ride specification? Is the control system easy to learn and operator friendly? What are the bar insertion capabilities? How easy is the machine to transport?
In addition to these questions, Fred Hite, Power Pavers, adds that concrete depth, width and tolerance limits related to smoothness should also be considered.
Smoothness is playing an increasingly important role in paver selection, since most jobs have smoothness bonuses and/or penalties tied to them. ?Ride specs are driving a lot in paver selection,? says Devonshire. ?The smoother the ride, the higher the bonus.?
There are many factors that go into achieving smoothness, including the size and weight of the machine. Usually, the heavier machines with higher horsepower ratings will yield a smoother road, especially for deeper, wider slabs.