Wheel Loads/Tire Pressure

Phase I

Phase II

CC3 Testing – Phase 2

LFC4

Objective: Measure interaction of response from one gear relative to another gear. Responses to be measured with the repaired MDDs and the pressure cells.

1.     Run three wander patterns for each of the mean wander positions (offsets) in the table below. Zero offset is with the center of the north carriage in the center of the test pavement. Plus15 ft offset is with the center of the south carriage in the center of the south wheel-track. Wheel loads to be 55,000 lbs.

2.     Use the standard wander pattern programmed exactly the same for both carriages. The wander patterns are to be synchronized (the north carriage goes left when the south carriage goes left, etc.).

3.     Repeat two of the offsets with wheel loads of 45,000 lbs and 65,000 lbs. Three wander patterns for each combination of load and offset. Select the offsets after preliminary examination of the data from the runs with 55,000 lb wheel loads.

4.     Run three wander patterns for each of the mean wander positions (offsets) in the table below. Zero offset is with the center of the south carriage in the center of the test pavement. Minus15 ft offset is with the center of the north carriage in the center of the north wheel-track. Wheel loads to be 55,000 lbs. Use the standard wander pattern and synchronize the wander patterns.

LFC1

Objective: Video tape the rapid deterioration of the pavement and the pattern of failure.

1.     Backfill the trench to provide support for a full wander pattern of the six-wheel gear with the mean wander position along the center of the test pavement (zero offset). Need to decide whether to backfill the subgrade as best as can be done or fill with the P-154 material. Also, how to place the asphalt?

2.     Traffic the center of the test pavement to failure with six wheels at 55,000 lb wheel loads using the normal wander pattern. The pavement should fail in less than 250 repetitions. (approximately four wander patterns). Take video with two cameras to show the progression of the failure. One camera close and the other long.

3.     Think about making profile measurements.

LFC2

Objective: Measure the number of repetitions to failure with zero wander for comparison with the previous traffic test to failure with wander.

1.     Backfill the two trenches as in LFC1.

2.     Traffic the center of the test pavement to failure with six wheels at 55,000 lb wheel loads and with no wander of the carriage.

LFC3

Objective: Measure the number of repetitions to failure with two gears close together. The amount of time available for this test will depend on the weather. May not be able to finish.

1.     Backfill the construction joints with fresh asphalt, either hot or cold.

2.     Traffic the south lane with the four-wheel south carriage and traffic the center of the test pavement with the six-wheel north carriage. Wheel loads to be 55,000 lbs and both carriages to be wandered in synchronization.

3.     The north carriage offset to be set at zero (center line of the test pavement) and the south carriage offset to be set at plus 9 ft (this gives 54 inches between the adjacent carriage wheels and is also the closest possible separation).