As published in:
High Performance Composites, September 2006
Engineered to Innovate-Composite Cores Evolve to Meet New Challenges
By Ginger Gardiner, Contributing Write, Ray Publishing

WebCore Technologies (Miamisburg, Ohio) manufactures the TYCOR_® family of fiber reinforced foam cores. Their proprietary process places fiber reinforcement through the thickness of closed cell foam sheets to form a corrugated or vertical truss-type structure, which is then infused with epoxy or other resin to produce a very robust and damage-tolerant core material.

WebCore began working with the U.S. Air Force in 2001 to redesign AM-2, the U.S. military's workhorse airfield mat system, in use for over forty years. The system is currently comprised of 2-ft by 12-ft aluminum panels, which are 1.5-inch (38 mm) thick aluminum extrusions with extruded end connectors along all four edges to provide a locking mechanism. There are three main problems which WebCore's TYCOR material seeks to solve: weight, bad joint design and damage during shipping.

A simple airfield large enough to support a fighter squadron requires 480 pallets of AM-2 matting, weighing around 1.3 million pounds (about 590 metric tons), filling up 48 C-130 transport aircraft, and requiring five days to install with one crew working 12-hour shifts. Currently, the system weighs 6.4 lb/ft², which amounts to roughly 150 lbs (68 kg) for a 2-ft by 12-ft panel. The Air Force wants to reduce this by 50 percent, plus they want a different joint system.

The current system is not only cumbersome, but requires numerous pieces of support and maintenance equipment. The edges are complex shapes, rendered unusable if damaged, and repairing a damaged panel requires starting from an edge and unlocking each panel in the airfield, working across sometimes up to one hundred panels in order to reach the one panel that is damaged. This adds to the current very time-consuming installation. A lightweight replacement with an easier joint design will alleviate these problems.

The target weight is 3.2 lb/ft². "We are very close to achieving that with a composite structure," states Rob Banerjee, vice president of business development for WebCore. "Our design is a 4-ft by 7-ft panel with aluminum extrusion joints on four sides of the panel." (WebCore is also working on new joint designs, including some made from composites, for even more weight savings down the line). WebCore's new system has a simpler connection design, which overlaps adjoining panels, not only enabling transfer of loads but reducing the number of loose parts and minimizing or possibly even eliminating the need for subgrade preparation and repair.

WebCore's airfield mat solution uses a carbon skin with carbon TYCOR reinforcement and high-performance foam. The resin matrix is epoxy, with toughening additives being considered for future developments. The system is consolidated via RTM or infusion. According to Banerjee, WebCore's is the only composite solution being evaluated by the Air Force right now, and it will undergo large-scale testing in August. This testing involves 1,000 sq. ft. of panel, installed on soft soil for maximum structural stress, subjected to 1,000 landings by the two worst aircraft for maximum landing loads: the F-15 fighter jet and the C-17 Globemaster III cargo transport. The F-15 produces a 35,000 lb (15,875 kg) single load on one very small tire. The C-17 spreads its load over many more wheels, but transmits over half a million pounds to an airfield each time it touches down. Airfield mat panels have to withstand 1,000 landings from each aircraft, and if the new composite system passes the next step will be a 10-year contract starting in 2007.

Download/View TYCOR Core for Airfield Matting