Evaluation of Trapezoidal Shaped Grooves

two trapezoidal-shaped grooved areas provided researchers with a direct baseline comparison between the two groove patterns. Details on each proposed location are as follows:  Runway 10 Threshold Area. The first test area began at the threshold of Runway 10, shown as block A in figure 42. From that point, the 750-foot-long test section began with 250 ft of trapezoidal-shaped grooves, 250 ft of standard grooves, and finally 250 ft of trapezoidal-shaped grooves. This test section ended approximately 750 ft from the threshold of Runway 10. This area was selected to capture landing traffic on runway 10. Details of the area are shown in figure 43.  Runway 10 Touchdown Area. The second test area began 1000 ft from the threshold of Runway 10, shown as block B in figure 42. From that point, the 750-foot-long test section began with 250 ft of trapezoidal-shaped grooves, 250 ft of standard grooves, and 250 ft of alternative grooves. This test section ended approximately 1750 ft from the threshold of Runway 10. This area was selected to capture the touchdown area where the heaviest rubber contamination may be experienced as the aircraft touchdown on the pavement. Details of the area are shown in figure 43.  Runway 10 Rollout Area. The third test area began 7711 ft from the threshold of Runway 10, shown as block C in figure 42. From that point, the 750-foot-long test section began with 250 ft of trapezoidal-shaped grooves, 250 ft of standard grooves, and 250 ft of alternative grooves. This test section ended approximately 8461 ft from the threshold of Runway 10. This area was selected to capture heavy braking and sharp turning from aircraft attempting to exit Runway 10 on Taxiways M6. Details of the area are shown in figure 44.

A B

C

Figure 42. The ORD Test Area

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