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Publication Number: FHWA-HRT-08-056
Date: November 2008

LTPP Manual for Profile Measurements and Processing

CHAPTER 5. PROCESSING OF PROFILE DATA IN THE OFFICE

5.1 INTRODUCTION

The profile data collected by inertial profilers, longitudinal profile data collected with a Dipstick®, and transverse profile data collected with a Dipstick® are sent to the RSC office for processing. In the LTPP program, ProQual is used to process data collected by these three methods, and to perform quality assurance checks on those data. After the data are processed and quality assurance tests have been performed, data files to upload to the LTPP PPDB are created by ProQual. This chapter presents guidelines for processing and performing quality assurance checks in the office for all three data types described previously to ensure consistency and uniformity amongst the RSCs.

These guidelines should be viewed as the minimum required amount of data checking to be performed by the regions. The RSCs may already have procedures in place that exceed the minimum requirements described in this chapter. In such circumstances, the RSCs should continue to use those procedures in addition to those presented in this chapter. The guidelines for processing and performing quality assurance checks are presented separately for each data type. As described previously, the processing and evaluation of profile data for all three data types is performed using ProQual. For each type of profile data, general guidelines on the menus and features in ProQual needed to perform data processing and quality assurance checks are described. Detailed information on the operation of ProQual is presented in the ProQual Manuals.

The RSCs are not required to process profile data collected at WIM sites by inertial profilers, except to perform quality assurance checks if needed to make sure that data are error free. However, the RSCs are required to store the profile data at WIM sites according to the procedures described in section 5.6

5.2 INERTIAL PROFILER DATA

The following are the recommended procedures to be used in the office for processing and performing quality assurance checks on longitudinal profile data collected with the ICC inertial profilers:

  1. Check the analysis Parameter Screen and Equipment Screen in ProQual. After starting ProQual, check if the settings in the Analysis Parameter Screen and Equipment Screen are set to values described in section 2.2.6.2.

    The following parameters in the Analysis Parameter Screen should be checked to see if they are set to the correct value: Running Average, Sample Length, Fault Threshold, Spike Threshold 1, Spike Threshold 2, Tolerance on Mean, Tolerance on Standard Deviation, Slope Variance Interval, Mays Coefficients, and RMSVA Base Length. (Note: The values for Sample Length, Fault Threshold, and RMSVA Base Length are not used in computations, but it is recommended that they be kept at the values indicated in section 2.2.6.2).

    The Equipment Screen should be checked to see if the following parameters are set to the correct values: Manufacturer, Description, Serial #, Vertical Photocell Offset, and Horizontal Photocell Offset.
  2.  
  3. Compute the roughness indices. In ProQual, select the data set to be analyzed and click the "All" icon to compute all roughness indices (i.e., IRI, RMSVA, Slope Variance).
  4.  
  5. Review the header information and End of Run Comments. The header information and End of Run Comments for all profile runs can be reviewed by selecting the "Browse" option in the "Run Details" menu of ProQual. The following are the fields that need to be reviewed and they are presented in the order they appear when the "Browse' option is selected:
    1. Time: The time of profiling shown is obtained from the computer in the profiler during testing. Review the time to see if it is reasonable. If it is unreasonable, the time shown in the computer of the profiler should be checked for possible errors. If errors are detected, check with the operator to obtain the correct time when profile data were collected.
    2.  
    3. Sequence: Check if the sequence identifier is correct. The value in this field is not uploaded to the LTPP PPDB. However, an incorrect value may affect the archival procedures used in the RSCs.
    4.  
    5. Software: The software version that is shown should be 1.07, followed by the last five digits of the VIN number of the profiler vehicle (i.e., 1.0768231, 1.0768394, 1.0768395, or 1.0768396). Check if the last five digits of the software field match the VIN number of the profiler of the RSC. If the VIN number is not correct, that means the serial # was not correctly entered into ProQual (see section 2.2.6.2).
    6.  
    7. Filter: The value in this field should be 100. If not, it means that the Filter Wavelength was set incorrectly when the data were collected. If a value other than 100 has been used to collect the data, discard the data and profile data will have to be recollected. Also, check the settings of the Filter Wavelength in the profiler software to ensure that it is set to a value of 100.
    8.  
    9. Crew: Check if operator and driver initials have been entered correctly. The operator and driver should be identified by two characters each, the first letter of their first and last names. Operator and driver names should be separated by a forward slash and typed in capital letters (e.g., CK/RS). If profiling is done as a one person operation, the operator and driver name should be the same (e.g., CK/CK).
    10.  
    11. Road: This field should show the route number where section is located (e.g., I-88). Check if the information is correct.
    12.  
    13. Lane: This field refers to the lane that was profiled. Valid entries are INSIDE or OUTSIDE. Check if the entry in this field is correct.
    14.  
    15. Direction: This field refers to the travel direction when profiling the site. Valid entries for this field are NORTH, EAST, SOUTH, or WEST. Check if the travel direction is correct.
    16.  
    17. Begin: This is an entry made for the field Beginning Description in the profiler software. Check to see if the milepost has been entered in this field. If not, this field should show NONE.
    18.  
    19. End: This is an entry made for the field Ending Description in the profiler software. Check to see if this field indicates NONE or has the ending milepost.
    20.  
    21. Surface: This field shows the surface condition of the road. Valid entries are V. GOOD, GOOD, FAIR, and POOR. As this field is selected in the profiler software by toggling through these four possible values, an entry will always be present for this field. This is a subjective entry made in the field by the operator based on a set of guidelines described in step 22 of section 2.3.4.1. It is recommended that the value assigned to the section during the previous site visit be reviewed when checking this field. Otherwise, there could be variability in the value assigned to this field from one year to another (e.g., V. GOOD during latest visit, but value for previous visit was GOOD).
    22.  
    23. Temperature: This field shows air temperature at the time of profiling in degrees Celsius. Check if the value appears reasonable based on season or month of testing. If the temperatures appear to be questionable, check with the operator who collected the data.
    24.  
    25. Clouds: This field shows cloud condition at the time of profiling. Valid entries are CLEAR, P. CLOUDY (Partly Cloudy), or CLOUDY. As this field is selected in the profiler software by toggling through the three possible values, an entry will always be present for this field. However, there is no easy way to check if the entry is correct.
    26.  
    27. Weather: The value in this field corresponds to the field "Other Weather Conditions" that was entered in the ICC software. In the ICC software, the operator has the option of toggling through the following entries and selecting the appropriate one: CONDITIONS OK, STEADY CROSSWIND, WIND GUSTS, HOT AND HUMID, HAZY, and LOW SUN ANGLE. As this field is selected in the profiler software by toggling through the six possible values, an entry will always be present for this field. If there is a question about this entry, check with operator to verify the entry is correct. The information in this field should be used when evaluating profile data (see step 5).
    28.  
    29. Start Method: The start method for profile data collection is always PHOTOCELL. The code assigned to photocell is one. Verify that this field shows one. If a method other than Photocell has been used to collect the profile data, discard the profile data and profile data will have to be recollected.
    30.  
    31. Stop Method: The stop method for profile data collection is always DISTANCE. The code assigned to distance is three. Verify that this field shows three.
    32.  
    33. Stop Distance: The stop distance for GPS and SMP sections is 152.40 meters. Verify that the value is correct. For SPS projects, see if value appears reasonable. The stop distance shown for SPS projects is the length of the entire profile run.
    34.  
    35. Wavelength Initialization: For ICC profilers, this field should show a value of 2.
    36.  
    37. Average Speed: This field shows the average speed during profiling, which should normally be 80 km/h. However, higher values are also possible, as this manual indicates the operating speed may be increased to 88 km/h depending on traffic conditions. If a speed higher than 88 km/h is entered, the reason for the higher speed should be checked. If the speed is less than 80 km/h, the reason for the lower speed must be checked to verify it was due to the posted speed limit or prevailing traffic conditions.
    38.  
    39. Note: This field shows an entry made in the field by the operator at end of a profile run. The operator has the option of choosing one of the following entries from the drop down list in the ICC software: RUN OK, PAVEMENT SURFACE DAMP, TRAFFIC CONGESTION: SPEED VARIABLE, DIFFICULT TO MAINTAIN CONSTANT SPEED: UPGRADE, DIFFICULT TO MAINTAIN WHEEL PATH LOCATION, and LATE PHOTOCELL INITIATION. If none of these comments is appropriate, the operator has the option of typing in an entry. If the Run End Note is not one of the six ICC options, check if the Run End Note follows the guidelines described in section 2.2.7.8. The comment in this field will be useful when graphically comparing profile plots (step 5) and when evaluating IRI values of profiler runs (step 8).
    40.  
    41. Operator Note: This field shows comments made by the operator in the field after data have been reviewed through ProQual. Review comments and see if they follow the guidelines presented in section 2.2.7.8. Comments will be useful when graphically comparing profile plots (step 5) and when evaluating IRI values of profiler runs (step 8).
    42.  
    43. Device Code: The code shown in this field should be P.
    44.  
    45. Manufacturer: This field shows the profiler manufacturer and should reflect the value set in the Equipment screen of ProQual (see section 2.2.6.2). Check if the manufacturer is International Cybernetics.
    46.  
    47. Model: This field shows the profiler model and should reflect the value set in the Equipment screen of ProQual (see section 2.2.6.2). Check if the model is MDR4086L3.
    48.  
    49. Model Code: This field shows the model code assigned to the profiler and should reflect the value shown in the Equipment parameter screen of ProQual, which is 3.
    50.  
    51. Sample Size: This field shows the sample interval for profile data, which was assigned to "Sample" in the Analysis Parameter screen of ProQual (see section 2.2.6.2). Sample size should show a value of 150.
    52.  

    If there are errors in any of the headers that can be corrected, go to the "Identification and Conditions" menu under the "Run Details" tab and correct the header. If there are errors that cannot be corrected (e.g., not using the photocell to initiate data collection, using an incorrect filter) discard the data. Profile data will have to be recollected.
  6.  
  7. Check the profile data interval. Go to the "Profile Details" tab in ProQual and check if data are at 150 mm intervals and that data for 152.4 m are available (sections two and five in SPS-6 projects should have data for 304.8 m). Although the Analysis Parameters screen was checked to see if the running average was set to 150 mm, there is always the possibility that this value was not set to the correct value in the field. A review of the Location field in the "Profile Details" tab will verify that the Running Average was set to 150 mm.
  8.  
  9. Perform a graphical run-to-run comparison of profile data. The graphical run-to-run comparison of profile data involves making a visual comparison of the data obtained for the multiple runs. This comparison is performed separately for the left, right, and center paths. The "Graphic Profiles" option in ProQual is used to do the comparison. The profiles should be evaluated for repeatability. End of Run and Operator Notes entered by the operator in the field should be reviewed when the comparison between profiles is made. In addition, the Field Activity Report should also be reviewed to see if the operator has made any additional comments related to profiler runs in that report. If variations between the profile runs are noted, the runs showing the variability should be reviewed to see if any of the following conditions contributed to the variability: DMI shift, testing out of the wheel path, or variability that is not pavement related.
  10.  
  11. Evaluate spikes in the profile. The "Spikes" tab under "Data Sets" in ProQual shows the locations where spikes were detected in the profile. Review the Operator Notes to determine the cause(s) of the spikes. If spikes were noted, it is mandatory that the operator note if the spikes were pavement related. When performing the run-to-run profile comparison, evaluate if spikes occur at same station for different runs. The results of the previous distress survey can also be used as a tool to evaluate if pavement features caused the spikes. The visit-to-visit profile comparison described in the next step can also be used to check if spikes were noted in the previous visit.

    If the cause(s) of the spikes is determined to be non pavement related, logically mark the locations where spikes are noted. This is done in the "Profile Details" tab in ProQual that shows the profile elevations; the spike is logically marked by changing entry in "Include" from "True" to "False." When a data point is logically marked, the data point is not used when computing profile indices.
  12.  
  13. Perform the graphical visit-to-visit comparison of the profile data. The visit-to-visit profile check involves making a visual comparison of profile data from the current visit with data from the previous visit. The "Graphic Profiles" option in ProQual is used for this comparison. Profile data for the previous visit is obtained from the LTPP PPDB. The comparison is made only along the left and the right wheel paths, as center path data for the previous visit is not available in the LTPP PPDB.

    Data obtained for multiple profile runs from the previous site visit should be evaluated and one representative profile run should be selected to perform the visit-to-visit comparison (it is permissible to select more than one run for the comparison). Profile data for the previous site visit should be overlaid with at least three good profile runs from the current data set, and the data for the two site visits should then be evaluated to determine if similar profile features are present in both data sets and to determine if profile shapes are similar. This comparison should be performed separately for each wheel path.

    If there are differences in profile features and shapes between the two data sets, the cause(s) for the difference should be evaluated. When ICC profiler data are compared to data collected with K. J. Law T-6600 profilers, differences in long wavelengths may be seen. However, the profile features for both devices should be similar. When the comparison involves only ICC profiler data, both profile features as well as profile shapes should be similar. If a good match is not obtained, use data from two previous site visits and perform comparison. If no explanation for the differences in profiles is found, paper copies of the profiles should be submitted to appropriate RSC personnel for review.

    When reviewing data for sections that were subsectioned (e.g., SPS sections), the visit to visit graphical profile comparison can be used to determine if subsectioning was performed correctly. If a horizontal offset of profile features is noted between visits, this may indicate a problem with subsectioning. If a horizontal shift in profile data is noted between visits for a section, check if it occurs for other sections in the SPS project. Based on feedback provided by the regions on typical profile shifts noted between visits, a shift of up to 1 m between visits is acceptable. If a subsectioning problem is suspected, reevaluate the subsectioning performed for the SPS project (or other cases where subsectioning was performed).
  14.  
  15. Review the profile indices. If a spike was logically marked, the "All" icon in the "Analysis" submenu of the "Data Sets" tab has to be selected again to recompute roughness indices. If no spikes were logically marked, it is not necessary to recompute the roughness indices. Print the Site Visit Report and Site Summary Report.

    Use a Site Visit Report to review the following: IRI Statistics (such as minimum IRI, maximum IRI, mean IRI, standard deviation of IRI, and IRI coefficient of variation), Run-to-Run Confidence Limits, and the IRI values obtained along left and right wheel path as well as the mean (both) IRI between runs. Use Site Summary Report to review the values computed for IRI, Spike Count, RMSVAs, Mays Output, and Slope Variance. Compare IRI values obtained from the current visit with those from previous visit. If difference in IRI value exceeds 10 percent for a wheel path (when mean IRI from all good runs are compared), check to see if cause for IRI change can be identified. If no explanation is found, paper copies of profiles including a graphical profile printout should be submitted to appropriate RSC personnel for review.
  16.  
  17. Assign a RCO Code and RCO Note:
    1. RCO Code: A RCO Code must be assigned to each profile run after quality assurance checks are performed on the data. Those checks include: (a) review operator comments, (b) compare IRI values and review IRI coefficient of variation for replicate profile runs collected during site visit, (c) compare profile data of replicate runs collected during site visit, (d) review spikes in profile data and review operator comments regarding spikes, (e) compare profile data with those collected during previous site visit(s), and (f) if required, review distress maps to investigate spikes in the data.

      Once these tasks have been completed, assign a RCO Code to each profile run using the guidelines presented in section 5.4. The RCO Code is assigned in the "Results and Status" tab of the "Run Details" sheet in ProQual.
    2.  
    3. RCO Note: A RCO Note must be made for each profile run. The RCO Note is assigned in the "Results and Status" tab of the "Run Details" sheet in ProQual. A drop-down list is available in this field to select an appropriate comment. The person reviewing the data also has the option of typing in a comment in this field, or to select a comment from the drop-down list and then type in additional comments.
    4.  

    The following are reasons for making an entry in the RCO Note field:
    1. Indicate locations where spikes were logically marked.
    2.  
    3. Indicate improper DMI calibration.
    4.  
    5. Indicate if spikes are pavement related.
    6.  
    7. Indicate cause(s) for variability in profiles.
    8.  

    The following comments are available in the drop-down list:

    1. PROFILE DATA OK, SPIKES ARE PAVEMENT RELATED,
    2.  
    3. VARIABLE PROFILES,
    4.  
    5. SPIKES IN WHEELPATH REMOVED,
    6.  
    7. POOR PROFILE MATCH: DMI DIFFERENCE, and
    8.  
    9. POOR PROFILE OVERLAY: ROUGH PAVEMENT.
    10.  

    Any comments typed in this field must be in capital letters.

    If there are no specific comments to make regarding a profile run, the comment "PROFILE DATA OK" must be selected from the drop-down list in the RCO Note field.
  18.  
  19. Select runs for upload to LTPP PPDB and create upload files. From all available profile runs, select five profile runs for upload. Thereafter, create RIMS upload files. Check ProQual Export Review Summary Report for errors and exceptions and if any are found resolve the issues and recreate RIMS upload files, as needed.
  20.  
  21. Submit RIMS files to the appropriate RSC personnel for review and upload to LTPP PPDB. If any problems are encountered during upload of RIMS data to LTPP PPDB, they should be resolved and the corrected data should be uploaded to LTPP PPDB.
  22.  
  23. Backup the data. The profile data files collected by the profiler (hereafter referred to as raw profile data) as well as all files generated by ProQual during processing of raw profile data should be backed up. For the ICC profiler, the raw profile data files that need to be backed up are the files with extensions of p, e, and v. All files generated by ProQual for each site should be backed up in conjunction with the raw profile data files. Use the file structure indicated in directive GO-41, Submission of Electronic Data for Customer Support and AIMS (or current version of that directive) to back up the data.
  24.  

5.3 LONGITUDINAL DIPSTICK® DATA

The following are the recommended procedures to be used in the office for processing and performing quality assurance checks on longitudinal profile data collected with a Dipstick®:

  1. Check if the Dipstick® passed pre and post measurement checks and if the data met the closure error. Check form DS-7 to verify that Dipstick® passed zero check and calibration check prior to and after data collection. Check form DS-1 to verify that closure error was within acceptable value.
  2.  
  3. Enter the header information. This section presents general procedures on navigating through the different ProQual menus and specifies the information that should be present in the header fields. Details on procedures for navigating between menus are presented in the ProQual Manuals.(6,7,8) To enter header information of a site into ProQual, select "Manual" from main menu, and then select the "Longitudinal" option. Thereafter, select the site from the left side of the screen (if the site has not been created in ProQual, create the site by selecting "System" in Main menu and then selecting the "Sites" option). Select the "Insert Data Set" icon (+ icon) and edit/enter information in the following fields in the Manual Data Set part of the screen:
    1. Name: The default entry shown in this field contains the LTPP Section ID, Current Date, and Current Time (for example, if the + icon was selected on 13 May 2003 at 1:36:10 PM for site 261000, the entry shown in this field will be, 261000 Manual Data Set: 13/May/2003 1:36:10 PM). Edit the date and time in this field to the show data collection date and the time at which data collection was started. This information is contained in form DS- 1.
    2.  
    3. Sample Interval: This field shows a default value of 304.8 mm. The spacing between the two footpads of all Dipsticks® used in the LTPP program is 304.8 mm. No change is required to this field.
    4.  
    5. Date: Enter the date of data collection from sheet DS-1.
    6.  
    7. Time: Enter the time data collection started from sheet DS-1.
    8.  
    9. Equipment: Select the appropriate Dipstick® model number from a drop down list, such that the Model Number and Equipment Number corresponds to the Serial Number and Model Number shown in form DS-1. If the required Dipstick® Model Number and Serial Number is not available in the drop down list, then the appropriate Dipstick® information should be entered in the "Equipment" screen of ProQual.
    10.  
    Check if all entries are correct and save the data. After the data are saved, the Manual Header entry fields will appear on the screen and the information in following fields will have to be edited or entered: Road Name, Site Type, Visit, Run Length, Units, Lane, Direction, Crew, Clouds, Temperature, Weather, Surface Type, Surface Condition, Operator Comment, and Run End Comment. The entries for Road Name, Site Type, Visit, Lane, Direction, Crew, Clouds, Temperature, Weather, Surface Type, and Surface Condition are available in form DS-1. Check if entries meet the following criteria (described in section 3.3.5.2) and enter information into the appropriate field in ProQual:

    1. Road Name: The highway or route designation in entered in this field. Enter information in capital letters (e.g., INTERSTATE 57, US 395, S.R. 31).
    2.  
    3. Site Type: The drop-down list gives the following options: SPS, GPS, SMP, CAL, WIM. Select appropriate site type. This information is not entered into the PPDB.
    4.  
    5. Visit: Select appropriate sequential visit identifier. (e.g., A for first visit to site, B for second visit, C for third visit, etc). Check if visit identifier is correct and enter value. This information is not entered into the PPDB.
    6.  
    7. Run Length: This field is used to enter the length of the test section in meters, which will usually be 152.4 m. Once the data set is saved, this value cannot be edited. Therefore, make sure that the correct value is entered as it is used to generate the data entry tables in the "Profiles" tab.
    8.  
    9. Units: This field shows a default value of mm. All Dipsticks® used in the LTPP program show readings in millimeters. Therefore, no change is required to the value shown in this field.
    10.  
    11. Lane: Use drop down list and enter lane, which can be either OUTSIDE or INSIDE. Check if lane is correct.
    12.  
    13. Direction: This is traffic direction of test section. Use drop down list and select NORTH, EAST, WEST, or SOUTH. Check if direction is correct.
    14.  
    15. Crew: Operator and recorder should be identified by two characters each, first letter of their first and last names. Operator and recorder names should be separated by a forward slash and typed in capital letters (e.g., CK/RS).
    16.  
    17. Clouds (Cloud Conditions): Valid entries for this field are CLEAR, P. CLOUDY, or CLOUDY. Use drop-down list in ProQual to select appropriate entry.
    18.  
    19. Temperature: The average of the air temperatures obtained from the air temperature probe before and after longitudinal Dipstick® measurements is entered in this field. Check if temperature appears to be reasonable based on season/month when test was performed and, if reasonable, enter value. If not, check with the operator.
    20.  
    21. Weather Comment: ProQual contains the following predetermined comments: CONDITIONS OK, STEADY CROSSWIND, WIND GUSTS, HOT AND HUMID, HAZY, LOW SUN ANGLE. Select appropriate comment based on information contained in form DS-1 using the drop down list. If there is a weather related comment that is different from those available in the drop down list, type the comment in this field using capital letters.
    22.  
    23. Surface Type: Use drop-down list to select surface type; A-CC for asphalt surfaced pavements and P-CC for PCC surfaced pavements based on surface type entered in form DS-1. Check if the surface type is correct.
    24.  
    25. Surface Condition: Enter condition of pavement as either V. GOOD, GOOD, FAIR, or POOR. Use drop-down list to select entry that is noted in form DS-1. Since this is a subjective entry made in the field by the operator, it is recommended that the value assigned to the section during the previous site visit be reviewed when checking this field. Otherwise, there could be variability in the value assigned to this field from one year to another (e.g., V.GOOD during latest visit, but value for previous visit was GOOD).
    26.  
    27. Operator Comment: Enter operator comments in capital letters, if the operator made any comments.
    28.  
    29. Run End Comment: Enter Run End Comment in capital letters, if the operator made a comment.
    30.  
    Once all header entries have been entered and checked, save header information.
  4.  
  5. Enter the longitudinal Dipstick® data. Enter the Dipstick® survey readings recorded on forms DS-2 through DS-6 into the "Profiles" sheet in ProQual. The exact sign convention used in the data sheets should be followed when entering the data (i.e., a negative value in data sheet should be entered as a negative value into ProQual). Once data have been entered for the left and the right wheel paths, print the data by clicking on the Printer icon. Check Dipstick® data values along the left and right wheel paths in the printout with values in forms DS-2 through DS-6 to make sure all data have been entered correctly.
  6.  
  7. Sum the Dipstick® data and filter profile using the Surface Dynamics filter. After checking the data and making corrections as needed, click on the sum button to obtain elevation profile as well as the elevation profile that has been filtered with the Surface Dynamics upper wavelength cut off filter. This action will cause the four data columns right of the left profile reading column to be populated with data. (Note: The Surface Dynamics filter included with ProQual was used in the K.J. Law T-6600 profilers as the upper wavelength cut off filter). Thereafter, click on the Update Main Tables icon to update the main tables with the filtered profile data. (Note: ProQual provides the option of filtering the Dipstick® elevation profile with either the Surface Dynamics or ICC filter. Longitudinal Dipstick® data are collected on a regular basis at test sections in Alaska, Hawaii, and Puerto Rico. In order to provide consistency in data collected at these sites, the Surface Dynamics filter must be used to filter Dipstick® profiles).
  8.  
  9. Compute ride indices and review the data. The data set can now be treated as a profiler run that was obtained using an inertial profiler by selecting the "Profiles" menu from the main menu of ProQual, and then selecting the "Data" submenu. Select the data set to be analyzed and in the "Analysis" submenu of the "Data Sets" menu select the "All" icon to compute all roughness indices (i.e., IRI, RMSVA, Slope Variance). Review if spikes are present in the profile. If spikes are present, check to make sure that the spikes were not caused by errors during data entry. Print the Site Summary Report to review the values computed for IRI, Spike Count, RMSVAs, Mays Output, and Slope Variance. Plot profiles along the left and right wheel paths and review profile plots to see if they are reasonable.
  10.  
  11. Compare the data with data from a previous visit. Compare IRI values obtained along each wheel path with those obtained during previous site visit. If the difference is greater than 10 percent for a wheel path, investigate the reason for the difference. Graphically compare profiles along each wheel path with those generated from a previous site visit. If major differences are noted between the two data sets, and no explanation for differences is found, paper copies of the profiles should be submitted to appropriate RSC personnel for review.
  12.  
  13. Review the Operator Comment and Run End Comment. The Operator Comment as well as the Run End comment was entered into the header menu in step 2 (Enter Header Information). If needed, make changes to the Operator Comment or Run End Comment based on the review of profile data.
  14.  
  15. Assign a RCO Code and RCO Note

    RCO Code: A RCO Code must be assigned to the profile data after quality control checks have been performed on the data. Those checks include:
    1. Review operator comments.
    2.  
    3. Compare IRI values along each wheel path with those obtained during previous site visit.
    4.  
    5. Review spikes in profile data and review operator comments (if any) regarding spikes.
    6.  
    7. Compare profile data with those collected during previous site visit(s).
    8.  
    9. Review distress maps to investigate spikes in data if required.

    10.  
    Once these tasks are completed, assign RCO Code to profile runs using guidelines presented in section 5.4. The RCO Code is assigned in the "Results and Status" tab of the "Run Details" sheet in ProQual.

    RCO Note: A RCO Note must be made for each profile run. The RCO Note is assigned in the "Results and Status" tab of the "Run Details" sheet in ProQual. A drop down list is available in this field to select an appropriate comment. The operator also has the option of typing in a comment in this field, or to select a comment from the drop down list and then type in additional comments.

    An entry in the RCO Note field should be made to indicate locations where spikes were logically marked and/or to indicate if spikes are pavement related.

    The following comments are available in the drop down list:
    1. PROFILE ATA OK.
    2.  
    3. SPIKES ARE PAVEMENT RELATED.
    4.  
    5. VARIABLE PROFILES.
    6.  
    7. SPIKE(S) IN WHEELPATH REMOVED.
    8.  
    9. POOR PROFILE MATCH: DMI DIFFERENCE.
    10.  
    11. POOR PROFILE OVERLAY: ROUGH PAVEMENT.
    12.  

    Any comments typed in this field must be in capital letters. If there are no specific comments to make regarding a profile run, the comment "PROFILE DATA OK" must be selected from the drop down list in the RCO Note field.
  16.  
  17. Create LTPP PPDB upload files. Select the longitudinal Dipstick® profile file for upload and create a RIMS upload file. Check the ProQual Export Review Summary Report for errors and exceptions, and if any are found resolve issue(s) and recreate RIMS upload files, as needed.
  18.  
  19. Submit RIMS files to appropriate RSC personnel for review and upload. If any problems are encountered during upload of RIMS data to PPDB, resolve the problems and upload corrected data to PPDB.
  20.  
  21. Backup the data. Backup all files related to the site that were created by ProQual. Use the file structure indicated in directive GO-41, Submission of Electronic Data for Customer Support and AIMS (or current version of that directive) to back up the data. Store the field data sheets and ProQual generated reports in appropriate files.
  22.  

5.4 ASSIGNMENT OF RCO CODE

A RCO Code must be assigned to the longitudinal profile data collected by the profiler as well as by the Dipstick® after quality control checks have been performed on the data. The assignment of a RCO code to profiler data is described in section 5.2 in step 9. The assignment of a RCO code to longitudinal Dipstick® data is described in section 5.3 in step 8.

The assignment of a RCO Code should be performed by a person knowledgeable in profile data analysis. This section provides guidance to the person who is performing the quality control checks in selecting the appropriate RCO Code to be assigned to each profile run. The following guidelines should be used to assign the RCO Code for a profile run:

  1. RCO Code = 1.

    A RCO Code of one should be assigned to a profile run if there are no data problems. Such profile runs have the following characteristics:

    1. If there is variability between multiple profile runs, the operator comments explain that the cause of this variability is pavement related.
    2.  
    3. If spikes are present in data, they occur because of pavement features and they are documented by the operator comments/notes to be pavement related.
    4.  
    5. If profile data plots are in good agreement with those collected during previous site visits. This procedure provides a check on errors caused by incorrect subsectioning of SPS sites, incorrect labeling of sites, and incorrect start locations for profile data collection.
    6.  
  2.  
  3. RCO Code = 2.

    A RCO Code of two should be assigned to a profile run if any of the following features are identified in the data:

    1. There is poor repeatability between the multiple profile runs, and operator comments do not indicate that this variability was caused by pavement features.

      It has been observed that sometimes profilers have poor repeatability on rough sections and on sections where the approach to the section is rough (e.g., patched core holes prior to section). On such sections, the data from multiple profiler runs are generally different from each other, with the operator having no comments regarding wheel path tracking problems. Although there are large differences in profile data, the IRI values from these runs are generally in good agreement with each other and may meet the ProQual IRI acceptance criteria. This occurs because differences in profile data are caused by long wavelengths that do not contribute to the IRI). Such profile runs should be assigned a RCO Code of two.
    2.  
    3. There are spikes in the profile.

      If there are spikes in the profile data, and the operator comments indicate that the spikes are not pavement related, such data points shall be logically marked and the profile run should be assigned a RCO Code of two.

      It has been reported that the white pavement markings at the beginning and end of a test section as well as 30 m crosses that are in the wheel path can cause spikes in the profile data. In such cases, the spikes will generally occur at the indicated locations for the replicate runs. If the operator indicates that these spikes are not explained by pavement features, such profile data points should be logically marked and the profile run assigned a RCO Code of two.
    4.  
  4.  
  5. RCO Code = 3.

    A RCO Code of three should be assigned to a profile run if any of the following conditions are identified:

    1. There is a large IRI difference that cannot be explained when compared to other profile runs collected during the site visit.
    2.  
    3. There are spikes in the profile data that are not explained by the operator comments.
    4.  
    5. There are differences in the profile data when compared to other profile runs collected during the site visit, but the differences cannot be explained by the operator.
    6.  
    7. The profiler runs collected during the site visit are repeatable, but they are different from those collected during previous site visits, and the differences are identified to be caused by conditions at the time of testing (e.g., damp pavement). It should be noted that data collection at LTPP test sections should be performed on dry pavements. There could be cases where data were collected on a damp surface due to existing circumstances.
    8.  
  6.  

5.5 TRANSVERSE DIPSTICK® Data

The following are the recommended procedures to be used in the office for processing and performing quality assurance checks on transverse profile data collected with a Dipstick®:

  1. Check if the Dipstick® passed pre and post measurement checks. Check form DS-7 to verify that the Dipstick® passed the zero check and calibration check prior to and after data collection.
  2.  
  3. Enter the header information. This section presents general procedures on navigating through the different ProQual menus and specifies the information that needs to be entered into the header fields. Details on procedures for navigating between menus are presented in the ProQual Manuals.(6,7,8) There are several header entries that are not entered in the LTPP PPDB. However, these entries may be useful if the ProQual files are reviewed at a future date.

    To enter header information for a site into ProQual, select "Manual" from main menu, and then select "Transverse" option. Thereafter, select the site from the left side of the screen (if the site has not been created in ProQual, create site by selecting "System" in Main menu and then selecting "Sites" option). Select the "Insert Data Set" icon (+ icon) and edit/enter information in the following fields in the Manual Data Set part of the screen:

    1. Name: The default entry shown in this field contains the LTPP Section ID, Current Date, and Current Time (for example, if the + icon was selected on 13 May 2003 at 1:36:10 PM for site 261000 the entry shown in this field will be, 261000 Manual Data Set: 13/May/2003 1:36:10 PM). Edit the date and time in this field to show the data collection date and time at which data collection was started. This information is contained in form DS-8.
    2.  
    3. Station Interval: The default value shown in this field is 15.24 m. This is the station interval at which transverse data are collected at LTPP sections. No changes are needed to this field.
    4.  
    5. Tests: The number of readings taken for a transverse profile. Enter the number of readings by reviewing data on form DS-8.
    6.  
    7. Date: Enter the date of data collection from sheet DS-8.
    8.  
    9. Time: Enter the time data collection started from sheet DS-8.
    10.  
    11. Equipment: Select the appropriate Dipstick® model number from drop down list such that Model Number and Equipment # corresponds to the Serial Number and Model Number shown in form DS-8. If the required Dipstick® Model Number and Serial Number is not available in the drop down list, then the appropriate Dipstick® information should be entered in the equipment parameters screen of ProQual.

      Check if all entries are correct and save the data. After data are saved, the Manual Header entry fields will appear on the screen and the information in following fields have to be edited or entered: Road Name, Site Type, Visit, Run Length, Units, Lane, Direction, Crew, Clouds, Temperature, Weather, Surface Type, Surface Condition, Operator Comment, and Run End Comment. The entries for Road Name, Site Type, Visit, Lane, Direction, Crew, Clouds, Temperature, Weather, Surface Type and Surface Condition are available in form DS-8. Check if entries meet the following criteria (described in section 3.3.5.2) and enter information into appropriate field in ProQual.
    12.  
    13. Road Name: This is the highway or route designation. Enter information in capital letters (e.g., INTERSTATE 57, US 395, S.R. 31). This information is not entered into the LTPP PPDB.
    14.  
    15. Site Type: The drop down list gives the following options: SPS, GPS, SMP, CAL, and WIM. Select appropriate site type. This information is not entered into the LTPP PPDB.
    16.  
    17. Visit: Sequential visit identifier. (e.g., A for first visit to site, B for second visit, C for third visit, etc). Check if the visit identifier is correct and enter the value. This information is not entered into the LTPP PPDB.
    18.  
    19. Units: This field shows a default value of mm. All Dipsticks® used in the LTPP program show readings in millimeters. Therefore, no change is required to the value shown in this field.
    20.  
    21. Lane: Use drop down list to select lane, which can be either OUTSIDE or INSIDE. Check if lane is correct. This information is not entered into the LTPP PPDB.
    22.  
    23. Direction: This is traffic direction of test section. Use drop down list to select NORTH, EAST, WEST or SOUTH. Check if the direction is correct. This information is not entered into the LTPP PPDB.
    24.  
    25. Crew: The operator and recorder should be identified by two characters each; first letter of their first and last names. Operator and recorder names should be separated by a forward slash and typed in capital letters (e.g., CK/RS).
    26.  
    27. Clouds (Cloud Conditions): Valid entries for this field are CLEAR, P. CLOUDY, or CLOUDY. Use the drop down list in ProQual and enter the cloud conditions. This information is not entered into the LTPP PPDB.
    28.  
    29. Temperature: The pavement temperature in degrees Celsius obtained with an infrared device is entered in this field. Check if the temperature appears to be reasonable based on season/month when test was performed and enter the value. This information is not entered into the LTPP PPDB.
    30.  
    31. Weather Comment: ProQual contains the following predetermined comments: CONDITIONS OK, STEADY CROSSWIND, WIND GUSTS, HOT AND HUMID, HAZY, LOW SUN ANGLE. If comment indicated in form DS-8 corresponds to one of the predetermined comments, use the drop down list to select an appropriate entry. If the comment is different, type the comment noted in form DS-8 (use capital letters). This information is not entered into the LTPP PPDB.
    32.  
    33. Surface Type: Use the drop down list to select the surface type noted in form DS-8. Use A-CC for asphalt surfaced pavements and P-CC for PCC surfaced pavements. This information is not entered into the LTPP PPDB.
    34.  
    35. Surface Condition: Enter the condition of the pavement as either V.GOOD, GOOD, FAIR, or POOR. Use the drop down list to select entry that was made in form DS-8. Since this is a subjective entry made in the field by the operator, it is recommended that the value assigned to the section during the previous site visit be reviewed when checking this field. Otherwise, there could be variability in the value assigned to this field from one year to another (e.g., V.GOOD during latest visit, but value for previous visit was GOOD). This information is not entered into the LTPP PPDB.

      There are three more header fields in the header menu: Operator Comment, Run End Comment, and RCO Comment. It is recommended that these three fields be completed after the transverse Dipstick® data has been entered and evaluated.

      Once all header entries have been made and checked, save header information.
    36.  
  4.  
  5. Enter the transverse Dipstick® data. The transverse Dipstick® data collected in the field and recorded on form DS-8 are entered into ProQual through the Profiles tab. The readings taken from Edge of Pavement to Center Line should be entered in the left column. The data for the return run (center of pavement to edge of pavement) should be entered in the right column. All measurements should be entered exactly as recorded on form DS-8, with negative values on form DS-8 entered into ProQual as negative values.

    All three boxes on top of the graph should be checked so that elevations are displayed for the following:
    1. Run from the edge of pavement to the centerline.
    2.  
    3. Run from the centerline to the edge of the pavement.
    4.  
    5. Sum of the two elevation measurements.
    6.  

    Once data have been entered, review and see if the graphical "Sum" plot is a horizontal line. If the line is not horizontal and spikes are noted at some locations, the data at those locations may have been incorrectly entered. If so, check if data have been entered correctly.

    After data have been checked for accuracy, click on "Verify Profiles." Confirm that the closure error limit has been met. If not, recheck the data entry. If the data do not meet the closure limit, the data from that run should be submitted to the FHWA with a copy to the LTPP Technical Services Support Contractor.

    Enter data for the other transverse locations. Follow the procedures outlined above to check those data.
  6.  
  7. Use the graphic profile option to check the profiles. After the data for all transverse profile runs have been entered, use the "Graphic Profile" option to plot the profile data. When this option is selected, a graph showing the profile plots for all transverse locations is displayed. Check if the profiles reasonably match between the stations. If a plot for any specific station appears to be different from the rest of the profiles, check the data that were entered for that location.
  8.  
  9. Run a rut analysis. Click on the "Rut Analysis" icon to compute rut depths and then print a Rut Report using the "Rut Report" icon. Review rut depths computed along the left and right wheel paths at different transverse locations. If the rut depth at any location appears to be different from those for the other locations, check if the data have been entered correctly.

    If the RSC maintains a record of rut depths computed by ProQual for a previous site visit, compare the current rut depths with those from the previous visit. The comparison should be made at each transverse location for each wheel path. If there are large differences, investigate if correct data have been entered.
  10.  
  11. Enter an Operator Comment, a Run End Comment, and a RCO Comment. The Operator Comment, Run End Comment, or RCO Comment is not uploaded to the LTPP PPDB. Therefore, entries made to these fields are only useful if the ProQual data files are reviewed at a future date. If the operator has made comments in form DS-8 related to data collection, enter the comments in the Operator Comment field. If all comments cannot be entered into this field, enter remaining comments in the Run End Comment field. Also, enter a RCO Comment if needed to comment on the data.
  12.  
  13. Create PPDB upload files. Run "IMS Export" to create RIMS files. If problems are encountered, resolve the issue and recreate the RIMS upload files, as needed.
  14.  
  15. Submit RIMS files to the appropriate RSC personnel for review and upload. The RIMS files should be submitted to appropriate RSC personnel for review and then uploaded to the LTPP PPDB. Resolve any issues that may arise during upload.
  16.  
  17. Backup the data. Backup all files related to the site that were created by ProQual. Use the file structure indicated in directive GO-41, Submission of Electronic Data for Customer Support and AIMS (or current version of that directive) to back up the data. Store the field data sheets and ProQual generated reports in appropriate files.
  18.  

5.6 STORING WIM DATA

Profile data collected at WIM sections should be stored at the RSC offices in external hard disk based media with a USB interface. RSCs should follow the naming convention specified in LTPP directive GO-41, Submission of Electronic Data for Customer Support and AIMS (or the current version of that directive) in the creation of the external drive. For the ICC profiler, the raw profile data files that need to be backed up are the files with extensions of p, e, and v. All files generated by ProQual for each site should be backed up in conjunction with the raw profile data files.

The storage of working files should be done in accordance with LTPP Directive GO-41, Submission of Electronic Data for Customer Support and AIMS (or current version of that directive).

In addition to the CD ROMs, the RSCs should maintain a file with the completed Profiling of WIM Sections: Data Summary Sheet (form PROF-7 in appendix C) for each occasion a WIM section has been profiled.

 

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The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT).
The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT). Provide leadership and technology for the delivery of long life pavements that meet our customers needs and are safe, cost effective, and can be effectively maintained. Federal Highway Administration's (FHWA) R&T Web site portal, which provides access to or information about the Agency’s R&T program, projects, partnerships, publications, and results.
FHWA
United States Department of Transportation - Federal Highway Administration