Evaluation of Trapezoidal Shaped Grooves

The total grooved area, including both the trapezoidal and the standard grooved sections, was estimated to be 37,500 square yards. The first two test sections were separated by a 250-ft section of standard grooves, as shown in figure 43. This was because of the proximity to the intersection of Runway 14R-32L. The location of the test areas on Runway 10-28 at ORD were optimal for allowing researchers to observe the performance and durability in an actual airport environment on a new asphalt surface. In addition, this location was optimal because it experiences a significant amount of aircraft traffic. Construction Process. One objective of this evaluation was to compare differences in the construction methods, resources, and requirements between the trapezoidal-shaped and the standard grooves in a real airport environment on an in-service runway. The intent of monitoring the construction process on the airport was to identify any differences in the construction aspect of the operation when performing the installation of trapezoidal-shaped grooves in a realistic airport environment. In February 2008, researchers initiated the installation of the grooves on Runway 10-28 at ORD. As with the MCAF Quantico installation, the contractor was able to mobilize all of the grooving equipment necessary to perform the installation from their facility on the east coast. The manpower, cutting equipment, supplies, water trucks, sweepers, and vacuum equipment used for the installation was the same equipment that would be used for a typical grooving job at any other airport; the only exception was that the groove-cutting machine was fitted with the uniquely shaped blades that create the trapezoidal-shaped groove. The same full-sized, groove- cutting machine that was used at MCAF Quantico was used at ORD, as shown in figures 28 and 29. Figure 45 shows a side-by-side comparison of the two grooved sections, as installed at ORD.

Figure 45. Trapezoidal-Shaped (Left) and Standard (Right) Grooves Installed on Runway 10-28 at ORD

45