CC7 South Profiler Data/Rut Depths

Straight-edge Profiles

Straight edge measurements were performed in accordance with ASTM E1703 [https://www.astm.org/Standards/E1703.htm].  A 16-foot aluminium beam was used as the straight-edge, and dial guages were used to measure the distance from the bottom of the straight-edge to the top of the pavement surface.  Measurements were performed across two transverse profile locations within each test item as shown below.

The maximum rut depth value along the full length of the beam was recorded using a dial gage.  At the beginning of trafficking, prior to primary stabilization of the pavement, measurements were taken every 24th and 66th pass of the vehicle.  After primary stabilization, measurements were taken after each wander (66 passes) until stabilization within the secondary zone was achieved.  Finally, measurements were taken at the end of each day’s testing.  Straight-edge depth measurements were used for comparison with Rail to Rail and Leica scan profiles.

Straight-Edge Measurements

Information on the straight-edge measurements can be found in the Profile portion of the database [here]

Rail to Rail Profiles 

The Rail to Rail Profiler is truss-mounted mechanical slide holding a laser distance measurement device.  The profiler takes vertical distance measurements while traversing the width of the test section to create a pavement profile.  Rail to Rail profiles were collected at the same transverse locations and at the same time relative to completion of trafficking as the straightedge measurements.  Rail to Rail profiles were used to generate maximum rut depth profiles using virtual straight-edge principles.  The rut depths measured by the Rail to Rail were compared to the straight-edge measurements.  Rail to Rail profiles also provided data for determining the maximum upheaval along each transverse profile location for comparison with the failure criterion. 

Leica Scan

3-D scans were performed using a Leica ScanStation P20 scanner.  The Leica P20 is a 360-degree Ultra-High Speed Laser scanner manufactured by Leica Geosystems. Scans were performed on a routine basis throughout the trafficking of CC7.  Leica scans were taken along the length of the CC7 test area.  Transverse profiles were extracted from the Leica scan at the same locations as the Rail to Rail profiles were taken. The Leica scan profile data for the Rail to Rail reference line was used to correct the Rail to Rail profiles to account for changes due to temperature influences on the apparatus.  

Leica P20 scanner

Special profiles were analyzed to support the overload testing. The pass numbers shown are the points immediately prior to the application of the overload and the pass at the end of the overload.  More information on the Overload Test can be found in the Construction Cycle 7 Test Report – Overload Test found [here]

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