Floor Load: We Do the Math

Live load. Ground pressure. Pounds per square foot. Arborists can run into certain situations where equipment weight and load rating can affect the structure they are operating and driving on at their jobsite, such as pool areas, patios and driveways. No need to panic like it's time for midterms. You have help in figuring it all out. 

Teupen is here to offer complete solutions for your height access challenges. Our compact track lifts can reach heights of 92 feet, but are lightweight enough to travel safely across practically any commercial surface. Before deciding on the proper equipment for the job, it's important to calculate the floor load requirements for any surface, from concrete slabs to concrete pavers. 

What exactly are we calculating? Here are some basic definitions that might provide clarity to common misconceptions. 
  • Force Impact The effect the compact lift has on the ground surface material itself (tile, concrete, wood, etc.). This is the measurement that determines the puncture point of the surface material and the structure itself. Another term for this concept is "point load," and should be considered when identifying the durability of the surface material when operating machinery on top of it, especially in the case of tile. Force is typically measured in pounds per square inch (psi).
  • Surface Load The effect the weight of the machine has on the surface material. This measurement reflects the weight or mass of the machine over the contact area with the floor. The question to ask here is: Can the surface material support the overall transient weight of the machinery when moving? In the case of a Teupen lift, the tracks' surface area in contact with the floor is much greater than a similarly capable wheeled machine.
  • Live Load Any temporary or transient forces that act on a building or structural element. Live loads typically include people, furniture, vehicles and virtually everything else that can be moved throughout a building. We measure uniform live loads as pounds per square foot (psf). The acceptable live load will vary considerably based on the occupancy and expected use of a structure or structural element. Live load considerations are important during both the transport and the operation of machinery on floor surfaces and the supporting structure.
The definitions above are important to understand when calculating the ground pressure or floor load for a specific job. Ground pressure is defined as "the pressure exerted into the ground by an object calculated by the object's weight divided through its ground contact area." Even with this precise definition, there are some common misconceptions around the idea of ground pressure. 
A few things to remember:
  • Ask for help. The equipment manufacturer or supplier should be able to provide all of the applicable measurements needed to calculate the impact of machinery on your floor surface.
  • Know your options. Track-mounted aerial work platforms are lightweight and spread the weight over a much greater surface area than traditional wheel-based equipment. A standard 60-foot boom lift weighs approximately 24,000 pounds as compared to Teupen's TC69A compact lift model at 6,600pounds.
  • Use under plates or outrigger pads. The use of pads, matting or dunnage will offer greater spread of weight and reduce both the point loads and live loads into the surface area.
While floor load requirements may appear complicated at first, there is a formula to determining the right specifications for every job. With a trusted partner providing expert assistance in calculations and implementation, you can be assured of a seamless operation every step of the way.