Engineered solution provides stability, safety
United States regulatory bodies and site owners continue to place emphasis on understanding ground conditions and using outrigger pads or crane pads to provide the necessary foundation support for heavy equipment. This includes proper matting, cribbing, and blocking.
While it’s possible to determine pressures to be exerted by the crane onto the ground for many lifts with smaller cranes, operators and crew members may not have that information readily available and are often left with determining the sufficiency of the ground and the current ground conditions. The most common way to solve the dilemma and help prevent catastrophic ground failure is to use outrigger pads or crane pads. Accurately sized and appropriately engineered outrigger pads will increase the area of contact the crane has with the ground, thereby reducing the ground-bearing pressure.
Cribbing blocks can be stacked in alternating directions and lock together to create a more secure set-up under the outrigger foot.
But what do you do if the ground is not level under all outriggers and you don’t have the time, equipment or materials to properly prepare the area? What if your work takes you to roadsides and ditches where the terrain is intentionally sloped? Typically, an operator’s only jobsite option is stacking timbers or some sort of wood that can be found on site to provide height under the equipment’s outriggers. Wood is inexpensive and convenient, but its porous and fibrous structure has inherent disadvantages that include unknown strength and rigidity properties that can result in cracking, breaking and splintering when exposed to outrigger pressure.
Cribbing products provide an engineered solution to these challenges. ProStack from DICA is designed to provide height for operators in environments where there are significant changes in grade. It is designed to be used under boom trucks, digger derricks, and aerial bucket trucks, or any equipment with outrigger loads that do not exceed 110,000 pounds.
The base ProStack Outrigger Pad is manufactured with a pyramid-shaped surface that interlocks with the cribbing blocks. Base pads come in four sizes: D2424-2, DR36-2, DR42-2 and DR48-2.
One of the first customers to put ProStack Cribbing into use was a major utility company. “The main benefit is the ability to provide cribbing to our crews that meets OSHA requirements for a stable setup,” said the utility’s transmission and substation safety coordinator. He explained that wood cribbing breaks down over time and, to be stable, layers of wood need to be bolted together. “But people rarely take the time to do that,” he said. “With ProStack, the interlocking design is stable, we are working with a known rating and working load limit, and it works with our existing outrigger pads so that we don’t have to carry another set of outrigger pads.”
Once the desired height is achieved, a ProStack Grip Pad is placed on top of the stack to protect the pyramid surface on the cribbing blocks and provide a high friction surface for the outrigger foot.
DICA’s ProStack Cribbing Kit is composed of three basic parts: a base outrigger pad, interlocking cribbing blocks and a high-friction top grip pad. The base outrigger pad is manufactured with a pyramid-shaped surface that interlocks with the cribbing blocks. On top of the base pad, operators stack layers of either DICA’s Medium Duty 6x12x12” or Heavy Duty 6x12x24” cribbing blocks with the pyramid-shape surface, which lock into the base pad. Lastly, a grip pad is placed on top of the stack to protect the pyramid surface on the cribbing blocks and provide a high-friction surface for the outrigger foot. To aid in the set-up, ProStack Wedges are available to fill the gap between the ground and the outrigger pad when the conditions call for it.
The more load you exert on the set-up the more ProStack locks together, increasing the safety of your set-up.
According to the utility’s transmission and substation safety coordinator, the cribbing wedges will be a tremendous benefit to transmission crews. “With the cribbing wedge, transmission crews may not even have to employ the cribbing blocks to level under outriggers for equipment setup on rights-of-way,” he said.
Cribbing Wedges are available when outriggers are set up on a slope to level the area under the ProStack Cribbing.
Scott Sutherland of AJ’s Concrete Pumping has found ProStack Cribbing gives his company a competitive advantage. “Having ProStack plastic cribbing blocks on our concrete pumps gives our operators the ability to set up quicker, easier, and above all else, safer,” he said. “The entire ProStack cribbing block system has given us a competitive edge in the market by allowing us to safely set up our equipment at minimal inconvenience to the general contractor.” UP
The Company: As a leader in engineered ground support products since 1988, DICA has continued to apply new technologies to outrigger pad and crane pad applications. ProStack Cribbing is strong and ergonomic, impervious to environmental conditions, manufactured from quality engineered materials and specifically suited to the job. Learn more at https://dicausa.com.