Office Procedures for Processing GPRProfiles

Non-Destructive Testing Unit

(January 2017)

** It is mandatory that you read the RADAN7Manual before proceeding. This manual is also a great reference for when you have issues with any phase of the layer-picking process. The manual can be found here: (B:)PavementAnalysis\NDT\GPR\RADAN

1)Open RADAN7 (GSSI’s current version)

1If it isn’t already open, under the ‘Home’ tab, click the ‘Global Settings’ icon:

Set ‘Source Directory’ to current Gpr file folder location

Set ‘Output Directory’ to current Gpr/Proc file folder location

Set ‘Display Channel’ to All

Set ‘Marker Style’ to Long

Set ‘Horizontal Scale‘ to Show

Set ‘Grid Lines‘ to Hide

Set ‘Vertical Units‘ toInches

Set ‘Horizontal Units‘ to Feet

Set ‘GPS Units‘ to *

Set ‘Auto-Switch Display‘ to No

Set ‘Current Display’ to Standard Processing

2*Other than the Source/Output Directories, you should only need to set these parameters once

2)Analyze GPR Profile Data

1Under the ‘Home’ tab, select the ‘Open’ icon

2Select the .DZT file in the GPR folder currently working on

Click ‘OK’ on the number of GPS points (*if this window doesn’t pop up the first time, no GPS was collected).

3After the software runs the entire length of the profile, a window will pop up asking to save the file:

If a single antenna was used to collect the data, add an underscore + 2ghz to the end of the filename (i.e. 420R000_2ghz).

If two antennas were used (2ghz & 400mhz), add an underscore + dual to the end of the filename (i.e. 420R000_dual).

4**See A and Bbelow to finish processing both types of files (single-antenna, dual-antenna)

  1. Processing A Single Antenna, 2Ghz Air-Launched File:

1In the ‘Properties’ window (Global Settings), change the ‘Source Directory’ to the ‘Gpr’ folder and ‘Output Directory’ to the ‘Proc’ folders of the file you are working on.

2Under the ‘Home’ tab, select the ‘Open’ icon

3Select the .DZT file in the GPR folder currently working on

4Click ‘OK’ on the number of GPS points

**If this window doesn’t pop up (the first time), no GPS was collected

5After the software runs the entire length of the profile, a window will pop up asking to save the file:

Add an underscore + 2ghz to the end of the filename (i.e. 420R000_2ghz)

6Under the ‘RoadScan’ tab, select the ‘Reflection Picking’ icon:

Change ‘Cal File Select Method’ to ‘User Select’

For the correct ‘Calibration File’, find and select the .CZT file from the current ‘Proc’ folder

‘Yes’ to ‘Automatic Mode’

Click ‘Apply’ (check to see that the solid black line around 4” down moved to the top of the screen – if it did, click ‘OK’ – if it didn’t, check ‘Time Zero’ or you could be using the wrong calibration file (.CZT)).

A window will pop up asking you to save the changes; to the end of the file, add a hyphen + rp (i.e. 420R000_2GHZ_rp)

Click ‘Save’

7Click the ‘Home’ tab

Turn the ‘Depth Pane’ and ‘Tables’ buttonson (if not already)

Adjust your ‘Display Gain’ and ‘Color Tables/Xforms’ to your liking

8Click back to the ‘RoadScan’ tab

9In the ‘Tables’ window (bottom of page):

Click the ‘Layers’ tab

  • Change the ‘Vel. Method’ cells to ‘Automatic’ (**2Ghz only; the 400Mhz should read ‘Default Vel.’).

10Make sure you are on ‘Layer 1’ by the ‘Focus’ button

11Choose the ‘EZ Tracker’ button

Then click the green ‘Start’ arrow

12Begin picking the first layer

13Occasionally, click the ‘Save’ button as you go along

14When you are finished with the first layer:

Click ‘Stop’

15Edit the layer picks by using either the ‘Single Point’ or ‘Select Block’ buttons

16When finished editing the first layer, click ‘Save’

17If choosing more than one layer, change the ‘Focus’ button to ‘Layer 2’ and follow step ten above.

18When all the layers are picked:

Click the black ‘Stop’ button

Click ‘Save’

Then click the ‘.CSV’ button (upper, far right)

  • Create a .csv file (place it in the current ‘Proc’ folder)

19**See the ‘NOS’ procedural instructions on how to process the .csv file

  1. Processing A Dual (2Ghz Hornand 400Mhz Ground)AntennaFile:

1Run through step 2 above

2For a Dual Antenna file: click on the ‘circle G’ ( ) > Save AsRADAN FileSplit Channels

Save = filename + ‘split’ (remove ‘dual’ from name)

  • example: 019R010_split / software will create 2 files: A = 2Ghz, B = 400Mhz
  1. To process the SplitA file (2Ghz):

1Under ‘Processes’, click ‘RoadScan’ > ‘Reflection Picking’

2Change ‘Automatic Mode’ to False

3Change ‘Starting Depth’ to 4” (only when collected with the 400mhz antenna)

4Under ‘Cal File Select Method’ > choose ‘User Select’

5Under ‘Calibration File’ > find and choose the calibration file used (.CZT)

6Click ‘Apply’ > if profile looks good then click ‘OK’

7Save = add a hyphen + rp to end of file (example: 019R010_splitA-rp)

8Continue with A./7 above

  1. To process the SplitB file (400Mhz):

1Under ‘Processes’, click ‘Time Zero’

Grab the signal (click/hold with mouse) and push up until the FIRST positive reflection is lined up with zero (see the RADAN7 manual).

Click ‘Apply’ – if the profile shifted properly, click ‘OK’; if not, make sure you are moving the signal properly in the previous step.

To Save: add a hyphen + tz to end of filename (i.e. 420R000_SPLITB-tz)

2Under ‘Processes’, click ‘Filters’, then ‘Background Removal’

Make sure the ‘BR Type’ is set to ‘Full Pass’

Click ‘OK’

To Save: add a hyphen + br to end of filename (i.e. 420R000_SPLITB-TZ-br)

3Under ‘Processes’, click ‘Gain’, then ‘Range Gain’

Alongside the ‘# Of Points’ row, choose a number between 2 and 5 – keep the number that makes the profile look the best.

  • Change the number then click ‘Apply’ to see the change; if you don’t like it, hit ‘Reset’ then try another number.
  • When you find the setting you like best, click ‘OK’ and save by adding a hyphen + rg to the end of the file (i.e. 420R000_SPLITB-TZ-BR-rg).

4You have finished filtering the file

5Under the ‘Home’ tab, click the ‘Processes’ button (to turn it off)

6Make sure both the ‘Depth Pane’ and ‘Tables’ buttons are both on

7Continue with A./7 above

Address: 40 Simon Street, Nashua, NH 03060-3075

Telephone Number: 603-893-1109

Toll Free Number (U.S. only): 800-524-3011

Fax Number: 603-889-3984

CUSTOMER SUPPORT MANAGER:

Dan Welch:

  • Direct: 603-681-2030 / Mobile: 617-818-7379

USER SUPPORT:

Roger Roberts / 603-681-2057

TECH SUPPORT:

Uri / 603-681-2096 - ext. 296

Rob Sommerfeldt

Application Specialist – Roads & Bridges, Concrete

Geophysical Survey Systems, Inc.

40 Simon Street • Nashua, NH 03060

603. 893.1109 main •603.681.2072 direct•603.889.3984 fax

Ken Corcoran

Product Marketing Manager

Geophysical Survey Systems, Inc.

40 Simon Street • Nashua, NH 03060

603.893.1109 main •603.681.2032 direct•603.889.3984 fax

Skype: corcorank1

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