Dynatest FWD User manual

DYNATEST FWD/HWD
TEST SYSTEMS
OWNER’S MANUAL
Version 2.8.17

2017.06.19 FwdMan2.8.17.docx
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Dynatest.
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!IMPORTANT SAFETY REMARKS!
Please Read this first:
For your own safety and the safety of others, please read this advice carefully.
An FWD/HWD is a powerful, hence dangerous piece of equipment that may injure persons in
cases of malfunction or mistreatment.
Things that may happen:
The weight may drop unexpectedly.
Hydraulic oil may leak at high pressure.
Hydraulic leakage may ‘DROP’ the loading plate assembly onto the ground.
A few simple rules for the operator:
Stay clear of the moving parts of the FWD/HWD if at all possible.
Make sure nobody else gets close.
Never place objects like e.g. tools at or near the buffer hit plate.
Do not leave the weight raised to drop position.
Do not leave the subassembly raised and unlocked.
Support the weight or subassembly during maintenance.
During demonstrations, training etc.:
Announce what you are about to do before you press any buttons.

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Overview
1. Introduction..................................................................................................................1-1
2. Tow Vehicle Installation..............................................................................................2-6
3. Computer Configuration...........................................................................................3-19
4. Program Configuration.............................................................................................4-25
5. Preparing for Measurements....................................................................................5-40
6. Weight Setup..............................................................................................................6-46
7. Connecting the Electronics .......................................................................................7-51
8. Leaving Base...............................................................................................................8-54
9. Running the Program................................................................................................9-56
10. Performing the Measurements ...............................................................................10-69
11. The Dynatest FWD/HWD Hardware.....................................................................11-84
12. Transducers/Cables...............................................................................................12-102
13. Calibration..............................................................................................................13-105
14. Setup Details...........................................................................................................14-113
15. The Compact15 System Controller......................................................................15-128
16. Maintenance...........................................................................................................16-135
17. Trouble Shooting....................................................................................................17-137
18. Optional Accessories..............................................................................................18-150
19. Data Formats..........................................................................................................19-153
20. Error Messages ......................................................................................................20-171

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Table of Contents
1. Introduction..................................................................................................................1-1
1.1 Intro...........................................................................................................................1-1
1.2 History.......................................................................................................................1-1
1.3 General Specifications ..............................................................................................1-2
1.4 Performance Specifications.......................................................................................1-5
2. Tow Vehicle Installation..............................................................................................2-6
2.1 Short form Vehicle Installation Guide......................................................................2-6
2.2 Notes for the Vehicle Installation .............................................................................2-9
3. Computer Configuration...........................................................................................3-19
3.1 Requirements ..........................................................................................................3-19
3.2 Network Settings.....................................................................................................3-22
3.3 Virus Protection ......................................................................................................3-22
3.4 Backup ....................................................................................................................3-23
3.5 Software Upgrades..................................................................................................3-23
3.6 Cameras...................................................................................................................3-24
4. Program Configuration.............................................................................................4-25
4.1 Dynatest Data Collection (DDC)............................................................................4-25
4.2 Applet Overview.....................................................................................................4-28
4.3 Completing the Setup..............................................................................................4-29
5. Preparing for Measurements....................................................................................5-40
5.1 Checking the FWD/HWD Hardware......................................................................5-40
5.2 Drop Heights Adjustment .......................................................................................5-41
5.3 “Lock error” and “Plate not low error”...................................................................5-45
6. Weight Setup..............................................................................................................6-46
6.1 Changing the UUFWDUU Weight Setup ..........................................................................6-46
6.2 Changing the UUHWDUU Weight Setup..........................................................................6-48
7. Connecting the Electronics .......................................................................................7-51
7.1 Connecting Transducers/Cables..............................................................................7-51
7.2 Connecting the Computer .......................................................................................7-53
8. Leaving Base...............................................................................................................8-54
8.1 Maintenance Checks ...............................................................................................8-54
8.2 Connect Trailer to Tow Vehicle..............................................................................8-54
8.3 Functional Check ....................................................................................................8-54
8.4 Just Before Leaving... .............................................................................................8-55
8.5 During Driving........................................................................................................8-55
9. Running the Program................................................................................................9-56
9.1 Switch ON...............................................................................................................9-56
9.2 Warnings.................................................................................................................9-56
9.3 Dynatest Data Collection (DDC)............................................................................9-57
9.4 The Data Collection Screen ....................................................................................9-63
9.5 Main Window .........................................................................................................9-64
9.6 Sub-Windows..........................................................................................................9-67
10. Performing the Measurements ...............................................................................10-69
10.1 Test Setups............................................................................................................10-69
10.2 Test Section...........................................................................................................10-75
10.3 Data Files ..............................................................................................................10-77
10.4 Running a Test ......................................................................................................10-78
10.5 Remarks ................................................................................................................10-79
10.6 Auxiliary Outputs X and Y...................................................................................10-79

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10.7 Closing the Data File.............................................................................................10-80
10.8 Opening a Data File ..............................................................................................10-80
10.9 Exporting Data......................................................................................................10-80
10.10 Monitoring the System’s Status ............................................................................10-81
10.11 Manual Control .....................................................................................................10-83
10.12 Exit........................................................................................................................10-83
11. The Dynatest FWD/HWD Hardware.....................................................................11-84
11.1 General Description ..............................................................................................11-84
11.2 Trailer Specifications............................................................................................11-86
11.3 FWD/HWD Hydraulics.........................................................................................11-87
11.4 Electrical System...................................................................................................11-95
11.5 FWD/HWD Trailer Mounted Power Unit (Generator - Optional) .......................11-98
12. Transducers/Cables...............................................................................................12-102
12.1 UUFWDUU Load Cell 86207........................................................................................12-102
12.2 UUHWDUU Load Cell 86205 .......................................................................................12-103
12.3 Seismic Detector 86211 ......................................................................................12-104
13. Calibration..............................................................................................................13-105
13.1 Relative Deflector Calibration ............................................................................13-105
13.2 Air Temperature Sensor Calibration...................................................................13-110
13.3 Surface Temperature Sensor Calibration............................................................13-111
13.4 DMI Calibration..................................................................................................13-112
14. Setup Details...........................................................................................................14-113
14.1 GPS .....................................................................................................................14-113
14.2 Cameras...............................................................................................................14-122
15. The Compact15 System Controller......................................................................15-128
15.1 Key Features .......................................................................................................15-128
15.2 General Description ............................................................................................15-128
15.3 Notes on Specifications.......................................................................................15-130
15.4 Switch ON...........................................................................................................15-130
15.5 Setup and Diagnostics.........................................................................................15-130
15.6 Description..........................................................................................................15-131
15.7 Manual Operation ...............................................................................................15-133
16. Maintenance...........................................................................................................16-135
16.1 Wheels/Brake System .........................................................................................16-135
16.2 Drop Weight Subassembly..................................................................................16-135
16.3 Electrical/Electronic Parts:..................................................................................16-136
16.4 Hydraulic System................................................................................................16-136
17. Trouble Shooting....................................................................................................17-137
17.1 Checking the Hydraulic Oil Level ......................................................................17-137
17.2 Switching off all Power.......................................................................................17-138
17.3 Checking Trailer Electronics Power ...................................................................17-138
17.4 Checking Trailer Battery Condition....................................................................17-138
17.5 Revealing hyd. leakage error ..............................................................................17-138
17.6 General Functional Checking of the Hydraulics.................................................17-139
17.7 Checking the Lower Plate/Raise Weight mode ..................................................17-146
17.8 Checking the DROP mode..................................................................................17-146
17.9 Checking the LOWER CATCH mode................................................................17-147
17.10 Checking the four Proximity Switch Sensors .....................................................17-147
17.11 Checking the Pressure Switches .........................................................................17-148
18. Optional Accessories..............................................................................................18-150

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18.1 Optional Hardware..............................................................................................18-150
18.2 Data Processing Software ...................................................................................18-152
19. Data Formats..........................................................................................................19-153
19.1 MS Access 2000 (MDB).....................................................................................19-153
19.2 Comma Delimited (F25).....................................................................................19-154
19.3 Nondelimited, 7+ Deflectors (F20).....................................................................19-159
19.4 Nondelimited, 7 Deflectors (FWD/HWD)..........................................................19-164
19.5 Pavement Deflection Data Exchange (DDX) .....................................................19-169
20. Error Messages ......................................................................................................20-171

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Full Table of Contents
1. Introduction..................................................................................................................1-1
1.1 Intro...........................................................................................................................1-1
1.2 History.......................................................................................................................1-1
1.3 General Specifications ..............................................................................................1-2
1.3.1 The FWD/HWD Mechanics............................................................................1-3
1.3.2 The Compact15 System Controller .................................................................1-4
1.3.3 The Remote Control Box.................................................................................1-4
1.3.4 The Computer..................................................................................................1-4
1.3.5 FwdWin, a Windows based FWD/HWD Field Program ................................1-4
1.4 Performance Specifications.......................................................................................1-5
1.4.1 Accuracy..........................................................................................................1-5
1.4.2 Reproducibility................................................................................................1-5
2. Tow Vehicle Installation..............................................................................................2-6
2.1 Short form Vehicle Installation Guide......................................................................2-6
2.1.1 General Remarks .............................................................................................2-6
2.1.2 Vehicle Type....................................................................................................2-6
2.1.3 Trailer Hitch ....................................................................................................2-6
2.1.4 Trailer Lights Socket (provided) .....................................................................2-6
2.1.5 Additional 12V Alternator...............................................................................2-6
2.1.6 Using/ (Replacing) the Existing Vehicle Alternator........................................2-6
2.1.7 Battery Separation Relay (provided if needed) ...............................................2-7
2.1.8 Electronics Buffer Battery (provided if required) ...........................................2-7
2.1.9 Heavy Fuse Box (provided).............................................................................2-7
2.1.10 12V Power Socket for Trailer (provided)........................................................2-7
2.1.11 Power Inverter (provided if needed)................................................................2-7
2.1.12 Throttle Regulator............................................................................................2-7
2.1.13 Alarm Connection Plug (provided) .................................................................2-7
2.1.14 Emergency Switch...........................................................................................2-7
2.1.15 Cable Access Opening.....................................................................................2-8
2.1.16 Placing the Computer ......................................................................................2-8
2.1.17 Air Conditioning..............................................................................................2-8
2.1.18 Warning Signs / Flasher Lights .......................................................................2-8
2.2 Notes for the Vehicle Installation .............................................................................2-9
2.2.1 Trailer Hitch Requirements .............................................................................2-9
2.2.2 Trailer Tail Lights Wiring .............................................................................2-10
2.2.3 System Powering...........................................................................................2-11
2.2.4 Plate-Low Alarm Connection........................................................................2-15
2.2.5 Cable Access Opening...................................................................................2-17
2.2.6 Placing the Computer and the Remote Control Box .....................................2-17
2.2.7 Warning Signs / Flasher Lights .....................................................................2-18
3. Computer Configuration...........................................................................................3-19
3.1 Requirements ..........................................................................................................3-19
3.2 Network Settings.....................................................................................................3-22
3.3 Virus Protection ......................................................................................................3-22
3.4 Backup ....................................................................................................................3-23
3.5 Software Upgrades..................................................................................................3-23
3.6 Cameras...................................................................................................................3-24
3.6.1 Camera Applet...............................................................................................3-24
3.6.2 HCamera Applet............................................................................................3-24

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4. Program Configuration.............................................................................................4-25
4.1 Dynatest Data Collection (DDC)............................................................................4-25
4.1.1 Vehicle ID......................................................................................................4-25
4.1.2 Driver.............................................................................................................4-25
4.1.3 User................................................................................................................4-26
4.1.4 Administrator.................................................................................................4-26
4.1.5 Options...........................................................................................................4-26
4.1.6 Entering the Main Program ...........................................................................4-27
4.2 Applet Overview.....................................................................................................4-28
4.3 Completing the Setup..............................................................................................4-29
4.3.1 Entering the Data Collection Screen .............................................................4-30
4.3.2 Loading Unit..................................................................................................4-30
4.3.3 Compact15 System Controller.......................................................................4-32
4.3.4 Load Cell .......................................................................................................4-32
4.3.5 Deflectors.......................................................................................................4-33
4.3.6 Program Options............................................................................................4-34
4.3.7 Air Temperature Sensor.................................................................................4-36
4.3.8 Surface Temperature Sensor..........................................................................4-37
4.3.9 Distance Measuring Instrument.....................................................................4-38
4.3.10 Global Positioning System (Optional)...........................................................4-39
5. Preparing for Measurements....................................................................................5-40
5.1 Checking the FWD/HWD Hardware......................................................................5-40
5.2 Drop Heights Adjustment .......................................................................................5-41
5.3 “Lock error” and “Plate not low error”...................................................................5-45
6. Weight Setup..............................................................................................................6-46
6.1 Changing the UUFWDUU Weight Setup ..........................................................................6-46
6.2 Changing the UUHWDUU Weight Setup..........................................................................6-48
7. Connecting the Electronics .......................................................................................7-51
7.1 Connecting Transducers/Cables..............................................................................7-51
7.1.1 Note on Load Cell Cable connection:............................................................7-52
7.1.2 Note on Placing the Deflectors......................................................................7-52
7.1.3 Important Notice!!!........................................................................................7-52
7.2 Connecting the Computer .......................................................................................7-53
7.2.1 Interface connections.....................................................................................7-53
7.2.2 Power Connections........................................................................................7-53
8. Leaving Base...............................................................................................................8-54
8.1 Maintenance Checks ...............................................................................................8-54
8.1.1 Tire Pressure..................................................................................................8-54
8.1.2 Hydraulic Oil Level.......................................................................................8-54
8.1.3 Battery Acid Level.........................................................................................8-54
8.2 Connect Trailer to Tow Vehicle..............................................................................8-54
8.2.1 Hook to Hitch ................................................................................................8-54
8.2.2 Rear Lights Connection.................................................................................8-54
8.2.3 Front Support Wheel .....................................................................................8-54
8.2.4 Power Cable...................................................................................................8-54
8.2.5 Network Cable...............................................................................................8-54
8.3 Functional Check ....................................................................................................8-54
8.4 Just Before Leaving... .............................................................................................8-55
8.4.1 Transport Locks (Automated or Manual)......................................................8-55
8.4.2 Raise/Lower Bar Locking Pin .......................................................................8-55
8.4.3 Trailer Handbrake..........................................................................................8-55

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8.5 During Driving........................................................................................................8-55
9. Running the Program................................................................................................9-56
9.1 Switch ON...............................................................................................................9-56
9.2 Warnings.................................................................................................................9-56
9.2.1 Emergencies...................................................................................................9-56
9.2.2 Stopping a Sequence......................................................................................9-56
9.2.3 Driving...........................................................................................................9-57
9.3 Dynatest Data Collection (DDC)............................................................................9-57
9.3.1 Applets...........................................................................................................9-57
9.3.1.1 Network .............................................................................................9-58
9.3.1.2 DMI....................................................................................................9-58
9.3.1.3 Speedometer.......................................................................................9-59
9.3.1.4 Thermometers....................................................................................9-59
9.3.1.5 GPS....................................................................................................9-59
9.3.1.6 Camera...............................................................................................9-60
9.3.1.7 Ground Penetrating Radar .................................................................9-61
9.3.2 Simulation Mode ...........................................................................................9-62
9.3.3 Entering the Main Program ...........................................................................9-62
9.4 The Data Collection Screen ....................................................................................9-63
9.5 Main Window .........................................................................................................9-64
9.5.1 Navigating with the Keyboard.......................................................................9-64
9.5.2 Special Keys ..................................................................................................9-66
9.6 Sub-Windows..........................................................................................................9-67
9.6.1 LED Panel......................................................................................................9-68
9.6.2 Time Histories ...............................................................................................9-68
9.6.3 Surface Moduli ..............................................................................................9-68
9.6.4 Surface Moduli Chart ....................................................................................9-68
10. Performing the Measurements ...............................................................................10-69
10.1 Test Setups............................................................................................................10-69
10.2 Test Section...........................................................................................................10-75
10.3 Data Files ..............................................................................................................10-77
10.4 Running a Test ......................................................................................................10-78
10.5 Remarks ................................................................................................................10-79
10.6 Auxiliary Outputs X and Y...................................................................................10-79
10.7 Closing the Data File.............................................................................................10-80
10.8 Opening a Data File ..............................................................................................10-80
10.9 Exporting Data......................................................................................................10-80
10.10 Monitoring the System’s Status ............................................................................10-81
10.11 Manual Control .....................................................................................................10-83
10.12 Exit........................................................................................................................10-83
11. The Dynatest FWD/HWD Hardware.....................................................................11-84
11.1 General Description ..............................................................................................11-84
11.2 Trailer Specifications............................................................................................11-86
11.3 FWD/HWD Hydraulics.........................................................................................11-87
11.3.1 General Description.....................................................................................11-87
11.3.2 Adjusting the Hyd. Pump Excess Pressure..................................................11-93
11.4 Electrical System...................................................................................................11-95
11.4.1 Transducers..................................................................................................11-95
11.4.2 FWD/HWD Control Circuits.......................................................................11-96
11.4.3 Trailer Status Switches................................................................................11-96
11.4.4 Hyd. Unit Connections ................................................................................11-97
11.4.5 Trailer Powering..........................................................................................11-97

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11.5 FWD/HWD Trailer Mounted Power Unit (Generator - Optional) .......................11-98
11.5.1 Generator Operating Instructions ................................................................11-99
12. Transducers/Cables...............................................................................................12-102
12.1 UUFWDUU Load Cell 86207........................................................................................12-102
12.1.1 Key Features..............................................................................................12-102
12.1.2 Description.................................................................................................12-102
12.1.3 Specifications.............................................................................................12-102
12.1.4 Calibration .................................................................................................12-102
12.2 UUHWDUU Load Cell 86205 .......................................................................................12-103
12.2.1 Key Features..............................................................................................12-103
12.2.2 Description.................................................................................................12-103
12.2.3 Specifications.............................................................................................12-103
12.2.4 Calibration .................................................................................................12-103
12.3 Seismic Detector 86211 ......................................................................................12-104
12.3.1 Key Features..............................................................................................12-104
12.3.2 Description.................................................................................................12-104
12.3.3 Specifications.............................................................................................12-104
13. Calibration..............................................................................................................13-105
13.1 Relative Deflector Calibration ............................................................................13-105
13.1.1 Data Collection..........................................................................................13-105
13.1.2 Analysis .....................................................................................................13-106
13.1.3 Gain Adjustment........................................................................................13-109
13.2 Air Temperature Sensor Calibration...................................................................13-110
13.3 Surface Temperature Sensor Calibration............................................................13-111
13.4 DMI Calibration..................................................................................................13-112
14. Setup Details...........................................................................................................14-113
14.1 GPS .....................................................................................................................14-113
14.1.1 Prefetch Maps............................................................................................14-113
14.1.2 Trimble Ag262 Setup ................................................................................14-114
14.1.3 Trimble BX982, Ver. 85992-01 (Basic Version) Setup............................14-117
14.1.4 Upgrading a BX982 to Ver. 85992-02 ......................................................14-121
14.2 Cameras...............................................................................................................14-122
14.2.1 Mounting ...................................................................................................14-122
14.2.2 Exposure....................................................................................................14-123
14.2.3 Unibrain Camera........................................................................................14-124
14.2.4 Unibrain Troubleshooting..........................................................................14-126
15. The Compact15 System Controller......................................................................15-128
15.1 Key Features .......................................................................................................15-128
15.2 General Description ............................................................................................15-128
15.3 Notes on Specifications.......................................................................................15-130
15.4 Switch ON...........................................................................................................15-130
15.5 Setup and Diagnostics.........................................................................................15-130
15.6 Description..........................................................................................................15-131
15.7 Manual Operation ...............................................................................................15-133
16. Maintenance...........................................................................................................16-135
16.1 Wheels/Brake System .........................................................................................16-135
16.2 Drop Weight Subassembly..................................................................................16-135
16.3 Electrical/Electronic Parts:..................................................................................16-136
16.4 Hydraulic System................................................................................................16-136
17. Trouble Shooting....................................................................................................17-137
17.1 Checking the Hydraulic Oil Level ......................................................................17-137

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17.2 Switching off all Power.......................................................................................17-138
17.3 Checking Trailer Electronics Power ...................................................................17-138
17.4 Checking Trailer Battery Condition....................................................................17-138
17.5 Revealing hyd. leakage error ..............................................................................17-138
17.6 General Functional Checking of the Hydraulics.................................................17-139
17.6.1 a) Brief Functional Description of the Hydraulics ....................................17-139
17.6.2 b) Checking the Hydraulic Modes.............................................................17-145
17.6.3 c) Checking the Hydraulic Solenoids/Valves............................................17-145
17.6.4 d) Hydraulic Solenoids Driver Circuits.....................................................17-145
17.7 Checking the Lower Plate/Raise Weight mode ..................................................17-146
17.8 Checking the DROP mode..................................................................................17-146
17.9 Checking the LOWER CATCH mode................................................................17-147
17.10 Checking the four Proximity Switch Sensors .....................................................17-147
17.11 Checking the Pressure Switches .........................................................................17-148
17.11.1 P1 check:....................................................................................................17-148
17.11.2 P2 check:....................................................................................................17-149
18. Optional Accessories..............................................................................................18-150
18.1 Optional Hardware..............................................................................................18-150
18.1.1 Distance Measuring Instrument.................................................................18-150
18.1.2 Global Positioning System ........................................................................18-150
18.1.3 Air/Pavement Temperature Probe .............................................................18-150
18.1.4 IR Surface Temperature Transmitter.........................................................18-150
18.1.5 Rear Extension Bar....................................................................................18-151
18.1.6 Rear/Side Extension Bar............................................................................18-151
18.1.7 Segmented Loading Plate..........................................................................18-151
18.1.8 Video Camera/Monitor Setup....................................................................18-151
18.1.9 Power Unit.................................................................................................18-151
18.1.10 Automated Transport Locks......................................................................18-151
18.1.11 Tandem Axle Trailer .................................................................................18-151
18.1.12 Special Trailer Colour ...............................................................................18-151
18.2 Data Processing Software ...................................................................................18-152
18.2.1 ELMOD.....................................................................................................18-152
19. Data Formats..........................................................................................................19-153
19.1 MS Access 2000 (MDB).....................................................................................19-153
19.2 Comma Delimited (F25).....................................................................................19-154
19.3 Nondelimited, 7+ Deflectors (F20).....................................................................19-159
19.4 Nondelimited, 7 Deflectors (FWD/HWD)..........................................................19-164
19.5 Pavement Deflection Data Exchange (DDX) .....................................................19-169
20. Error Messages ......................................................................................................20-171

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1. Introduction
1.1 Intro
A major advantage of analytically based structural design methods over more empirical
methods is that the former may be used with any type of material and structure and under all
climatic conditions, whereas the latter only may be used under those conditions for which the
empirical relationships were developed. Most pavement research effort has therefore
concentrated on developing and perfecting analytically based methods (e.g., the first six Ann
Arbor Conferences).
Analytically based methods can only be used if the moduli of the pavement layers can be
determined. This may be done if the test method allows for:
1. A force amplitude and duration approximating the effect of a heavy moving wheel load in
order to allow for non-linear and visco-elastic stress-strain response, and
2. Very accurate deflection measurements, especially at several large distances (i.e. larger
than the thickness of the pavement) from the centre of the load. This is absolutely essential
in order to get an accurate determination of the (non-linear!) Subgrade modulus, which
generally contributes some 60-80% to the total centre deflection.
The Dynatest 8000 FWD (Falling Weight Deflectometer) Test System, 8000 VMD (Van
Mounted Deflectometer) and 8081 HWD (Heavy Weight Deflectometer) Test System all
satisfy these conditions, whereas most vibrating equipment has a light load capacity, and
Benkelman or other beam type equipment is inaccurate at significant distances from the load
because the deflection gauge must be supported within the deflection basin itself.
The FWD, VMD or HWD may therefore - contrary to most other equipment - be used with
analytically based structural design methods.
1.2 History
Based on early work in France during the sixties, the Technical University of Denmark, the
Danish Road Institute and the Dynatest Group have gradually developed and employed the
Falling Weight Deflectometer (FWD) for use in Non Destructive Testing of highway and
airfield pavements. In 1977, the Dynatest 7800 Registration Equipment was introduced to
obtain digital load and deflection value readouts, although it was still necessary to hand place
the deflection sensors away from the load. Various research projects showed, however, that
simultaneous measurements of at least six deflections (plus the load) were necessary for quick
and precise deflection basin determinations, from which it became possible to evaluate the In
Situ E-moduli or stiffnesses of all structural layers in an existing pavement system through the
use of the Dynatest “ISSEM4” main frame Fortran computer program, and in the recent years
through the ELMOD PC computer program.
In 1979, Dynatest introduced the Model 8001 FWD featuring compact mechanical design
with integrated raise/lower sensor bar and remote control of all operations, including load

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1-2
level. Finally, the 7800 Registration Equipment was precluded in 1981 by a more compact
micro-processing system called the Dynatest 8600 System Processor. In conjunction with a
newer model FWD, the Dynatest 8002 FWD featuring a loading range of 7 kN (1,500 lbf) to
120 kN (27,000 lbf), and a matching Hewlett Packard HP-85 Computer, this system was able
to handle seven simultaneous deflections, one load and numerous site and configuration
identifiers, in very short order, by a single operator doing inventory work.
In 1986, the Computer program for the FWD Test System, called the Field Program, was
made DOS compatible and extended with a lot of features. The DOS compatibility made it
possible to use almost any IBM compatible PC as the Computer. The latest version of this
Field Program is Edition 20 (which may be replaced by the latest FwdWin program, see
below).
In 1987, Dynatest introduced a “big brother” to the FWD, the Dynatest 8081 HWD Test
System, which with a dynamic peak load capacity of up to 240 kN was developed to simulate
heavy aircraft loads. The HWD can, however, also be used for road evaluation at load levels
down to 30 kN. The Model 8081 HWD uses almost exactly the same electronics and software
as the Model 8000 FWD (apart from adjustments for the higher load capacity), so that the
HWD is producing data at the same high accuracy as the FWD.
In early 1989, a second-generation microprocessor control and data acquisition unit was
introduced, called the Dynatest 9000 System Processor, featuring two (and prepared for eight)
additional deflection channels, so that a total of 10 channels (1 load + 9 deflections) was
available (required Edition 25 or FwdWin Field Program - please see below). The 9000 had
several new features, e.g. a 40 character LCD display for system status monitoring (even
without a PC connected).
In 1992, Dynatest introduced the Edition 25 Field Program, based on Object Oriented
Programming, featuring window pull-down menus and a series of features over the Edition 20
FP, mainly providing for 9 (10) (and prepared for 15) deflection channels, 0.1 micron
deflection resolution, load sensing/targeting, on-line Help System, fast sampling/storage of
signal time histories, user modifiable data file format, etc.
In 2001, Dynatest introduced a Microsoft Windowsversion of the Field Program called
FwdWin. FwdWin now runs under Windows 2000, XP and Vista. It offers all the advantages
of a graphical user interface (GUI), plus real time display of many data elements. It also
utilizes Microsoft Accessdatabase format for data storage in addition to the traditional
ASCII data formats.
In 2003, a third-generation control and data acquisition unit was introduced, called the
Dynatest Compact15, featuring fifteen deflection channels, so that a total of 16 channels (1
load + 15 deflections) is available (FwdWin Field Program required - please see above).
Compact15 is an embedded computer unit mounted on the loading subunit and
communicating with the host computer through an Ethernet connection.
The FWD/HWD, including a Compact15 System Controller and a standard PC with the
FwdWin Field Program constitutes the newest, most sophisticated Dynatest FWD/HWD Test
System, which fulfil or exceed all requirements to meet e.g., ASTM D-4694 and D-4695
standards.
1.3 General Specifications
A Dynatest FWD/HWD Test System consists of five main components:
A Dynatest 8002 FWD Trailer, a van mounted FWD Subunit or an 8082 HWD Trailer.
A Dynatest Compact15 System Controller.
A Remote Control Box

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An IBM compatible computer like e.g., a Notebook or Laptop type PC with Windows.
The FwdWin field data collection program.
1.3.1 The FWD/HWD Mechanics
By means of a falling weight striking a specially designed rubber spring system, a Dynatest
FWD/HWD produces an essentially half-sine shaped, single “impact” load of 25-30 msec in
duration, closely approximating the effect of a moving wheel load of up to 120 kN (27,000
lbf) (optionally 150 kN (33,000 lbf)) for the FWD/VMD or 240 kN (59,000 lbf) (optionally
300 kN (66,000 lbf)) for the HWD.
Peak load range 7 to 120 (opt. 150) kN (1,500 to 27,000 (opt. 33,000) lbf) for the 8000
FWD or the VMD
Peak load range 30 to 240 (opt. 300) kN (6,500 to 54,000 (opt. 66,000) lbf) for the 8081
HWD
Light weight, trailer or van mounted. Trailer versions may be towed by an ordinary
passenger automobile or van.
Height of trailers less than 1.5 m (58”) in transport as well as measuring mode, low centre
of gravity, stable at normal highway speeds.
Centre mounted load cell, integrated with the loading plate and swivel suspended.
7 (optionally up to 15) seismic deflection transducers, in movable holders along a 2.45 m
(8 ft) raise/lower bar, for precise deflection basin measurements.
Automatic, remote controlled operation (including falling height selection) by one person
(the driver).
A typical testing sequence in one measuring point is performed in less than 40 seconds
(HWD: 50 secs.)
Weather resistant (–20C to +50C (–5F to +122F)) for all components located outside the
towing vehicle.
12V DC power requirement only, heavy duty buffer battery supply provided.

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1.3.2 The Compact15 System Controller
The Dynatest Compact15 System Controller is a PC based control and signal processing unit,
which is networked with the host computer (Ethernet).
A temperature controlled case, compact and light.
Controls FWD/HWD operation.
Performs scanning, conditioning and further processing of the transducer signals (1 load +
up to 15 deflections).
Monitors status of the FWD/HWD unit to ensure correct measurements.
12VDC powered.
1.3.3 The Remote Control Box
The Remote Control Box (placed in the towing vehicle) interfaces the Park Alarm signal and
switches on and off the System electronics and (optional) warning lights.
1.3.4 The Computer
The Computer is used for input of control and site/test identification data as well as for
displaying, storing (on disc), editing, sorting and further processing of FWD/HWD test data.
Ethernet RJ45 connector (10/100 Mbit)
1.3.5 FwdWin, a Windows based FWD/HWD Field Program
Features
User Interface
Flexible layout through floating, resizable windows
Voice feedback (error- and warning-messages)
Support for multiple languages
Data Files
Test data is stored in databases for ease of processing.
Earlier Dynatest ASCII file formats still supported.
Pavement Deflection Data eXchange (PDDX by AASHTO)
Section Database
The operator can retrieve Roadway network information in the field:
Facility Names and Codes
Sectioning
Structural information
Quality Assessment
Changes to primary program- and equipment-parameters are logged.

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1.4 Performance Specifications
1.4.1 Accuracy
The deflections are measured with an absolute accuracy of better than 2% ± 2 microns, and
with a typical, relative accuracy of 1% ± 1 micron. The resolution of the equipment (in terms
of deflection) is 0.1 micron (1 micron = 0.04 mil).
The load is measured with an accuracy of better than 2% ± 0.3 kN. The resolution of the
equipment (in terms of load) is 0.03 to 0.2 kN (7 to 45 lbf), magnitude dependent.
1.4.2 Reproducibility
The reproducibility of successive FWD/HWD tests run on the same elastic materials is
typically 1% in terms of the load/deflection ratio, for a given falling height and mass
configuration.

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2. Tow Vehicle Installation
2.1 Short form Vehicle Installation Guide
2.1.1 General Remarks
Normally, the delivery of a Dynatest FWD/HWD Test System does not include a towing
vehicle.
In this section, therefore, are given all Installation Instructions (and hints) necessary to
prepare a towing vehicle for a proper FWD/HWD System Setup.
In this section are NOT described all the “non-permanent” connections (regarding
transducers, computer power and interface cable) which are performed using quick-connect
plugs - refer to subsequent sections 7, “Connecting the Electronics” and 12,
“Transducers/Cables” for descriptions and cable diagrams.
The Hardware Installation Instructions are given below in a rather short form, backed up by
supplementary Notes where necessary (to be found in subsection 2.2).
Items followed by “(provided)” will be included in the system delivery or be shipped in
advance of delivery if so agreed.
2.1.2 Vehicle Type
The towing vehicle should be of adequate size and engine power to tow the FWD/HWD
trailer with max. permissible weight. The engine compartment should preferably allow for
space for an additional alternator (see below).
2.1.3 Trailer Hitch
The vehicle should be fitted with a trailer hitch with a 50 mm (or 2”) diameter hitch ball, the
centre of which should be located 480-500 mm (18-20”) above ground level when LOADED
with some 100kg (see also Note 2.2.1). The hitch must be rated for towing of the FWD/HWD
trailer max. permissible weight.
2.1.4 Trailer Lights Socket (provided)
A trailer tail lights connection socket should be mounted on the rear of the towing vehicle
close to the towing hitch ball (preferably in front of and some 200 mm to any side of the ball)
(see also Note 2.2.2).
2.1.5 Additional 12V Alternator
For optimum powering of the FWD/HWD Test System, an UUadditionalUU 12V alternator of at
least 60 Amp. output capacity, preferably 90 Amp. or more (HWD: at least 90 Amp.,
preferably 110 Amp. or more) should be mounted onto (and belt driven by) the vehicle engine
(see Note 2.2.3). ALTERNATIVELY, IF this solution is not possible/desirable, the vehicle’s
own (existing) alternator MAY be used under certain conditions. A third solution is using an
optional trailer mounted Power Unit, see notes in the following.
2.1.6 Using/ (Replacing) the Existing Vehicle Alternator
If it is NOT possible or desirable to mount an ADDITIONAL alternator in the towing vehicle,
then the vehicle’s EXISTING alternator MAY alternatively be used, IF it has an adequate
current output rating (FWD: at least 90 Amp. output capacity, preferably 110 Amp. HWD: at

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least 120 Amp. output capacity, preferably 150 Amp.). IF NOT, it could be REPLACED by a
heavier alternator, if available/possible.
A battery separating RELAY should be used (see below).
2.1.7 Battery Separation Relay (provided if needed)
IF (and ONLY if) the FWD/HWD System is powered from the EXISTING vehicle alternator
(or its replacement), a special, heavy duty battery separation RELAY should be installed (see
Note 2.2.3).
2.1.8 Electronics Buffer Battery (provided if required)
For buffering of the alternator generated 12VDC power supply to a 12VDC-to-110/220VAC
Power Inverter (see 2.1.11), an additional battery should be mounted in the vehicle cabin.
Preferably use a maintenance-free (“add-no-water”) 12V battery of 40-60 Ah capacity
(standard size in most small passenger vehicles) (see Note 2.2.3).
2.1.9 Heavy Fuse Box (provided)
A heavy fuse box should be installed for protection of the 12V power circuits (see Note
2.2.3).
2.1.10 12V Power Socket for Trailer (provided)
A heavy, 2-pin (female) power output socket for powering/charging of the trailer 12V electro
hydraulic system and buffer battery should be mounted close to the towing hitch ball (like the
lights output socket, but preferably to the opposite side of the ball (see Note 2.2.3).
2.1.11 Power Inverter (provided if needed)
If the Computer requires 110/220VAC powering, a 12VDC-to-110/220VAC Power Inverter
should be installed (see Note 2.2.3).
2.1.12 Throttle Regulator
If the Vehicle alternator capacity is in the low end, the vehicle engine should preferably be
fitted with a manual or automated throttle regulator, so that the engine UUidlingUU RPM can be
raised to 1000-1500, to ensure adequate 12VDC power supply from the alternator during
testing. On most new vehicles, this is difficult or not possible, in which case it is important to
use an alternator with an output capacity in the high end.
2.1.13 Alarm Connection Plug (provided)
A 3-pin DIN plug should be used for connection of the vehicle’s PARK indicator OR hand
brake (emergency brake) indicator to the ALARM socket on the Remote Control Box. This
enables the system to give a warning ALARM signal AND to automatically raise the loading
plate, if the vehicle is set into DRIVE (or the emergency hand brake is released) during testing
(see Note 2.2.4).
2.1.14 Emergency Switch
An emergency switch (with a momentary UUbreakUU contact) may be connected in series with the
above mentioned ALARM connection for immediate raising of the loading plate in an
emergency situation. This switch could e.g. be dash mounted and have a large, visible push
knob (see Note 2.2.4).

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2.1.15 Cable Access Opening
The towing vehicle should be fitted with some kind of an opening in the rear, so that the
network cable can be easily passed from the Computer to the Trailer (see Note 2.2.5).
2.1.16 Placing the Computer
The towing vehicle should be fitted with some kind of a small table or the like for the
Computer (see Note 2.2.6).
2.1.17 Air Conditioning
If necessary, the vehicle should be equipped with an air conditioner to keep the interior of the
vehicle below 40°C (105°F) (and to keep out dust from open windows). A white roof, tinted
glass and/or curtains can perhaps also be used to reduce sun heating.
2.1.18 Warning Signs / Flasher Lights
To warn the traffic during testing, warning flasher lights should be mounted on top of the
towing vehicle.
Warning signs may also be mounted on the rear of the vehicle and/or the Trailer (see also
Note 2.2.7).