The challenge for Washington Engineering & Construction Co. was formidable: Remove 4,300 square yards of concrete from the runway at Pittsburgh International Airport, clear out the ditches, install new electrical conduit for runway lights, and then install new concrete over top. After a conventional excavator faltered, the productive solution to the challenge was the Model XL 4300-II excavator by Gradall®, rented from Highway Equipment. Quick on its feet, it has rubber-tired mobility and power to get the job done quickly. The airport, a main hub for USAirways, had to remain in full operation during the project, so only designated sections of runway were allowed to be shut down for each phase of the project. To create channels for the conduit, concrete saws cut out sections of concrete that were 16 inches thick, 8-1/2 feet long and 4-1/2 feet wide. To save time, the contractor needed to remove the 7,800-pound concrete patches without breaking them into pieces, so use of a front end loader and the associated labor were quickly ruled out.
The first attempt to remove the massive patches of concrete involved the use of a conventional excavator. However, crews had to keep positioning heavy rubber mining belts under the excavator's crawler tracks. That was the initial advantage presented by the Gradall Model XL 4300-II, which could move over the concrete surface without damaging it. The Gradall also moved much faster over the length of the ditch, actually working faster than trucks could be positioned to haul away the concrete. Beyond the mobility, the contractor also was impressed with power provided by the machine's XL Series hydraulics. The machine easily lifted the 7,800-pound patches with a pavement removal bucket. Next, the Model XL 4300-II was equipped with a 48-inch ditching bucket without teeth, removing debris and again eliminating the need for costly hand work.
For more information about Gradall excavators call (800) 445-4752.