Improved Engineered Wood Fiber (EWF) Surfaces for Accessible Playgrounds Field Performance Testing: Final Report II

Bonded Impact/cushioning Surfaces

Eight different surface test specimens were formed with surface dimensions of 1.2m x 1.2m with a depth of 0.3m (48”x48”x 12”) in Madison WI (Figure 1). Seven had a top layer of bonded resin/EWF and the eighth was a full-depth EWF control. Two additional surfaces were made (Figure 1, A1 and E1) and each were duplicates of other surfacing test areas. A1 and E1 were on a slope to assure drainage of the entire test surface. All surfaces used Engineered Wood Fiber (EWF), as defined by ASTM F2075-01. All surfaced specimens were compacted to simulate the finished surface of a play area. Given that there is no industry, governmental, or association definition or standard for compacting EWF, we followed playground industry installation practices.

Figure 1. Overview of the test surfaces in Madison, Wisconsin. From top left along the concrete edge the test surfaces are A1, A2, B, C, D; then from top right toward the bottom, E1, F, G, E2, H (Note: A1 and E1 were not useable due to slope in excess of 5%).

Table 1: Summary of Surfaces Evaluated in Phase II Testing.

All Phase II surfaces (Table 1) were selected based on an evaluation of Phase I results. Any Phase I system which was shown to have either undesirable surface stability or resiliency was eliminated from Phase II testing. All Phase II surfaces were fabricated from EWF matched to Phase I materials and obtained from a commercial supplier (Zeager Bros. Obtained from their Oskaloosa, Iowa licensee.). A baseline “control” test surface was also made with only EWF.

Four bonding systems were used to fabricate these surfaces.These systems* are:

a) silicone-based, Dow-Corning AllGuard, a waterproofing coating,

b) a synthetic latex, Midwest Industrial Soil-Sement

c) a foaming polyurethane (Franklin ReacTITE 8143), and

d) a non-foaming polyurethane (Vitricon’s) Vitriturf

* Tradenames used only for the reader’s information and do not constitute an endorsement by USDA Forest Service.

One interfacial treatment was used for two of the surfaced specimens. A 1.2 m x 1.2 m (48 in. x 48 in.) single ply layer of lightweight polyolefin landscaping geotextile was placed between the unbonded and bonded layers of these specimens. The geotextile was intended to provide cotinuity for the thinner bonded surface layers in the event that they might fracture through the entire thickness. When this happens the layer could be ejected from its original position and become a hazard on the remaining bonded surface.