Florida Mat Rentals, a division of Mabey Bridge & Shore, provides HDPE mats - and safe access to unstable or sensitive work areas - on a variety of projects in the Southeast.
By Steve Hudson
How do you handle projects in wet, mucky, muddy, or environmentally sensitive terrain?
More specifically, how do you handle the fundamental matter of access?
Over the years there have been a number of solutions to that problem. Typically, they involve something like construction of temporary access roads or the use of timber matting. But temporary roads must often be removed, requiring time and expense, and timber mats have relatively short lives and some stiff handling requirements.
An alternative that's becoming increasingly well known among contractors in the Southeast is the use of sectional HDPE mats such as the Mabey Mats from Florida Mat Rentals. Mabey Mats have been used in applications ranging from access roads over unstable or environmentally sensitive areas to temporary turnarounds and staging areas. They're also used to protect asphalt or concrete paving, as well as architectural features such as decorative brick paving, while heavy equipment works in the area.
Another major application of these mats is in the electric power industry, where power companies and utility contractors use them to provide safe access to low-lying areas where soils may be wet, mucky and unstable.
"Here in the Southeast, particularly in parts of Florida and Georgia, power companies and utility contractors often have to work in low-lying areas where the ground conditions are not ideal," notes James Daniels, Florida Mat Rentals' operations manager. Such projects might involve replacement of power poles, he adds, which requires heavy cranes and other equipment. But the ground conditions can be very poor in those low-lying areas,which are often too soft and mucky for operation and access by the necessary equipment. The solution is to use mats, and that's what Florida Mat Rentals provides with site-specific, turnkey supply/install/removal packages. Florida Mat Rentals' parent company, Mabey Bridge & Shore, Inc. also offers the mats for rental.
Typical of these applications was one in Augusta, Ga, not long ago, where 16 inches of rain had made low areas all but inaccessible. At that location, Daniels says about 88 of the mats were used to provide needed access over what would have otherwise been an inaccessible expanse of muck and mud.
Another, near Melbourne, FL called on the mats during four-laning of Highway 192.
"Muck was being dug out along the side of the roadway," Daniels says "and we matted along the side of the road so that trucks could get in and dump replacement material." That job, he adds, required more than 200 mats.
"The mats can even go across submerged areas," he adds, "in order to allow machinery to pass while keeping engines out of the water." In fact, Florida Power Corp recently placed a five-mat-thick layer of these mats on just such a project in Gainesville, Fla. where access was required through an area where water was as much as 8 feet deep.
The mats can also be stacked on relatively dry land to level up areas that would otherwise be too uneven for equipment such as cranes to work safely. that was the case in Bartow, Fla., recently, where stacked mats were used to build a level crane work area during a power tower replacement operation.
"At each structure it took more than 100 mats to get a level surface," he says.
One of the larger matting jobs in the southeast, Daniels adds, took place recently in Tampa, where Tampa Electric was putting in new lines across a cow pasture. There, the mats were used to construct a 1.2-mile-long access road for machinery and equipment.
"That job required 1,038 mats," he says, adding that mat installation required 11 days, with six more days to remove the mats once the utility work was done.
The Mabey Mats are made from high-density polyethylene (HDPE). Matting is supplied in two sizes (8feet by 14 feet or 8 feet by 7.5 feet). The larger size mats weigh about 1,050 pounds a piece. Individual panels are manufactured with a built-in tread pattern for improved traction. Panels are 4.25 inches thick. Panel edges also have overlapping lip for joining multiple panels into a single mat; the panel edges are secured to one another using a drop-in locking pin system. That not only locks the panels together, ensuring an unbroken working or travel surface, but also distributes loads for safer and more stable working conditions.
Traffic testing suggests that they have an average life expectancy in excess of 15 years, with fatigue testing showing "no appreciable damage" after 60,000 cycles of 6 inches deflection of an 8-foot span.
To avoid problems with static electricity, which can be a problem with many plastic materials, the mats are manufactured with an additive that gives the material the ability to conduct electricity. this allows any static build-up to dissipate, all but eliminating the potential for static electricity arcing and shocks.
Installation of the panels to create an access road, staging area or other working area is straightforward. In some cases, depending on the situation and application, it may begin with placement of a layer of geotextile fabric. For long-term applications this geotextile layer minimizes mud seepage between panel joints while also allowing water to seep into the soil below the mats. For other applications, the panels can simply be placed on the ground.
In any case, once any necessary geotextile is placed, panel installation is simply a matter of placing the panels (typically done using a loader equipped with a fork attachment) and then securing them as required by the specifics of the individual job. Panels may be placed in a single row or staggered in rows to create wider areas; in either case, a system of locking pins is used to connect the individual panels into a single structural unit. A recent project near Loganville, Ga., a suburb of Atlanta, was typical. On that particular project, the job was to build temporary roadways over farmland and through swampy areas to provide access for installation of new electrical transmission poles. The resulting temporary access roadway would be used by large mobile cranes, an auger drilling machine, dump trucks, and pole trucks needed to handle the 90-foot-long steel transmission poles, as well as long-reach linesman's bucket trucks for stringing the new lines once the poles were in place. 
The mat panels arrived at the site on a large flatbed truck. Once there, they were unloaded from the truck using a loader - in this case a Cat 918F - equipped with a fork attachment and then stacked in a staging area.
On this particular project, no geotextile layer was used. Instead, the panels were placed directly on the ground. However, on parts of the project, two rows of the wider 14-foot by 8-foot panels were placed side-by-side to form a 16-foot-wide roadway.
Panel placement went smoothly. One by one, the Cat loader picked up each panel from the staging area, transported it to the proper location and then set it into position. Daniels, a master of the fine art of maneuvering individual panels into place, manned the loader and carefully nudged each panel into alignment with the one before it.
As the panel was set into place, FMR crew members Paul Peterson and Charlie Thibodaux used a steel bar to align the locking holes with the new panel with the holes in the panel set previously, then installed locking pins in each hole. A large steel hex key tool was then used to give each pin a twist to secure it and lock the panels together.
Installation of the matting went quickly. As the mat access road stretched across the farmland and then over the wet areas, the team worked smoothly to extend the mats one panel at a time.
After only a short time, the result was a solid and stable access way over terrain that would otherwise have posed significant challenges for equipment and material access.
"though the scope of the jobs we do has become more involved over the last few years, we think of these jobs as being 'ordinary,' " says Florida Mat Rentals' Joe Atkinson. But for those who count on the mat roads and work platforms, they're anything but that.
"They're what it takes to get them in and out," Atkinson says.