1. PORTABLE TRAFFIC MONITORING SITE INSTALLATION AND INSPECTION TRAINING
PRESENTED BY:
FLORIDA DEPARTMENT OF TRANSPORTATION AND SOUTHERN TRAFFIC SERVICES
RUBIE FRASE & TERRY ROBINSON

2. THE IMPORTANCE OF DATA COLLECTING
The State Road Department started collecting traffic data at ten locations back in As the state grew both in population and number of lane miles, the need to expand traffic data collection was obvious.

3. THE IMPORTANCE OF DATA COLLECTING
The value of good traffic data became apparent early on in the evolution of the national Department of Transportation (DOT) and eventually the Federal Highway Administration (FHWA).

4. THE IMPORTANCE OF DATA COLLECTING
This data is translated into revenue allocations for the state and federal highway programs.

5. THE IMPORTANCE OF DATA COLLECTING
Good data is a result of good site installations. Good count/speed/vehicle classification and weight data is essential to the following customers:
Some Internal Uses:
Roadway Design uses our data to determine if facility enhancements/lane additions are needed;
Pavement Design uses our data to determine pavement type & thickness requirements;
Traffic Operations/Maint. Use it to determine lane closure restrictions. And there are many others.

6. THE IMPORTANCE OF DATA COLLECTING
Data uses (cont.)
Some External Uses:
The FHWA compiles data for use in national trend reports, national Truck Weight Study and other studies and for apportioning funds back to us;
Advertisers and developers that need to know how many motorists are passing a given location in order to set sign and rates or determine potential demand for retail outlets, etc. (among many others).

7. THE IMPORTANCE OF DATA COLLECTING
Two categories of traffic monitoring sites have permanent equipment physically located in the roadway. These are TTMS and PTMS. They are the backbone of the traffic count program administered by the FDOT Central and District Offices.

8. THE IMPORTANCE OF DATA COLLECTING
The data collected at these sites may include: volume, speed, vehicle class and weight. The type of equipment installed and the programs set-up in the equipment determine how the site functions.

9. TTMS

10. TELEMETERED TRAFFIC MONITORING SITE
TTMS
TELEMETERED TRAFFIC MONITORING SITE
TTMS sites are the locations that are polled via modem daily by the TRANSTAT Central Office computers. They record and transmit every day of the year and provide the data used for adjusting short-term traffic counts to Annual Average Daily Traffic (AADT).
TTMS sites are installed and maintained out of Central Office in Tallahassee.
Many have solar panels

11. TYPE III PEDESTAL MOUNTED
PTMS
TYPE II BASE MOUNTED
TYPE III PEDESTAL MOUNTED

12. PORTABLE TRAFFIC MONITORING SITE
PTMS
PORTABLE TRAFFIC MONITORING SITE
PTMS locations are usually installed on high volume urban arterials where rubber hose counts or other equipment is difficult to install and maintain.

13. PTMS
Piezo
Loop
The permanent part of the installation is the cabinet and loop/piezo wires installed in the pavement. Greater reliability, personnel safety, and accuracy are the reason loops and piezos are preferred to hose counts.

14. PTMS
LOOP
PIEZO
Loops provide a volume count of vehicles crossing the loop sensors. The piezos provide classification count which measures the axles as the vehicle crosses the piezo.

15. PTMS
To gather data, a traffic counter is normally placed in the cabinet and attached to the wire harness for a short period (2 – 7 days) either annually or quarterly, then moved from one site to another, hence the term portable traffic monitoring site.

16. ADR-1000 COUNTER IN CABINET
PTMS
ADR-1000 COUNTER IN CABINET

17. HISTORY OF ISSUES Issue – PTMS Inspections Not Passing
Resolution – Train DOT, Construction, Contract and Sub-contract employees on how to install a PTMS site.

18. OBJECTIVE FOR THIS CLASS
Above all, the need to follow Design Standards and Plan Specifications.
Design standards are reviewed every year and changes made as needed. You need to keep a copy of the latest standards with you at all times.
The following slide reflects a major change to loops.

19. OBJECTIVE FOR THIS CLASS
Square Corners

20. OBJECTIVE FOR THIS CLASS
Above all, the need to follow Design Standards and Plan Specifications.
Review the plans and follow the placement, materials to be used and location precisely.
For Example: Loops are no longer to be cut at a 45° angle. Since the year 2001 the standard is to drill corners with a 1.5” bit by 2” minimum depth.

21. OBJECTIVE FOR THIS CLASS
Above all, the need to follow Design Standards and Plan Specifications.
Loops SHOULD NOT be cut across the concrete joint in the roadway. As the vehicles travel across the pavement, the pavement jars and could loosen the loop wires and render them useless.

22. OBJECTIVE FOR THIS CLASS

23. OBJECTIVE FOR THIS CLASS
Above all, the need to follow Design Standards and Plan Specifications.
Piezos come with a warranty card. The warranty card must be filled out and a copy of it placed in the cabinet along with a copy of the cabinet schematics.

24. OBJECTIVE FOR THIS CLASS

25. OBJECTIVE FOR THIS CLASS
Above all, the need to follow Design Standards and Plan Specifications.
The difference between a good and bad site!
Good Bad

26. OBJECTIVE FOR THIS CLASS
Above all, the need to follow Design Standards and Plan Specifications.
Every time a site does not pass on the first inspection is wasted tax payer’s money. This affects all of us including you.

27. GOING FORWARD
The plans are delivered to the Data Collection Manager, and they review them for proper location, design and placement.

28. GOING FORWARD

29. GOING FORWARD
The Data Collection Manager shall be contacted by the contractor and/or sub-contractor prior to any installation. This includes the cabinet, loops and piezos.

30. GOING FORWARD
The Data Collection Manager shall be contacted when the site has been installed and ready for inspection.
In most cases, there is a bonus tied to the project. If the site does not pass….your company may lose or be the cause of any bonus not being paid.

31. GOING FORWARD
In your travels throughout the district, if you find a damaged site, please do the following:
Take a picture of the damage.
Call Road Rangers or local police if the site was involved in an accident.
Contact the Data Collection Manager immediately.
In most cases, if the damage was caused by an accident, we can recoup the cost of repair from the at-fault insurance company.

32. CONTACT INFORMATION
RUBIE FRASE – I am the main contact person for District 5
– Office
Cell

33. TECHNICAL PRESENTATION
Presented by
Terry Robinson – Southern Traffic Services

34. Planning Materials Action
PRE-ENGINEERING
Planning Materials Action

35. PRE-ENGINEERING PLANNING
Sites are selected by the Data Collection and Planning Office in most scenarios.
Sites are approved by the District Engineers.
Plans are developed by the Office of Design and reviewed by the Data Collection Office.

36. PRE-ENGINEERING
PTMS sites are independent of one another, and sites are built to fit the location.
Numerous departments are involved with the building of a PTMS site. Statistics office, Planning office, Data office, Design office, Engineering office, Construction division, etc.

37. PRE-ENGINEERING Utility locates are completed
Pavement is cured and ready for sensors
All equipment is on hand and meets Approved Product List (APL) and Qualified Product List (QPL)

38. PRE-ENGINEERING Engineers have approved ALL Plans and changes
Schedules have been approved by: Project Manager, Project Engineer, Traffic Operations Engineer, Consultant
Maintenance of Traffic Plan submitted and Approved.

39. WHAT ARE THE COMPONENTS OF A PTMS SITE?
MATERIALS
Cabinet – Type III, IV, and V
Piezoelectric sensors
Inductive Loop sensors
Pull boxes
Grounding electrodes
Surge Protection
Conduit

40. MATERIALS Is cabinet in place? Does cabinet face the right direction?
Does cabinet meet plans and specifications?
Pull boxes in place and installed to specifications?
All conduits in place?
Have piezo sensors been tested prior to installation

41. MATERIALS Do loop wires and cables meet QPL?
Are epoxies and sealants approved?
Are dates on piezos, sealants and epoxies recorded?

42. ACTION Areas of Concern Maintenance of Traffic (MOT)
Review of MOT Plan
Placement of Temporary Traffic Control Devices
Any ADDITIONAL SIGNS REQUIRED?
District or Area Public Information Office Contacted?

43. ACTION
Verify all Public Safety and Local Governments are aware of Lane Closures
Update Traffic Operations if changes are made to MOT Plan
Notify ALL parties that all lanes are open upon completion

44. BREAK TIME

45. INDUCTIVE LOOP ASSEMBLIES
Inductive loops are simply a coil of wire embedded in the road’s surface.
The loops that are installed in the State of Florida and used by the FDOT are usually 6’ X 6’ loops using 12 gauge wire consisting of 4 turns.
2 loops are installed in each lane that work in conjunction with the Piezoelectric Sensors.

46. INDUCTIVE LOOP ASSEMBLIES
What is an inductor?
An inductor is simply a coil of wire or an electromagnet.
The inductor or wire has a very low resistance. When a vehicle passes over the loop, the inductance is elevated. This unit of increase is measured in “Henry’s”, or microhenries. The vehicle becomes the “inductor” or the coil.

47. LAYOUT OF SENSORS Verify the space of the sensors
Standard spacing is 16 feet from leading edge of leading loop to leading edge of trailing loop
Loops MUST be in CENTER of lane and MUST NOT cross expansion joints unless approved by Engineer prior to installations

48. LAYOUT OF SENSORS
Standard loops are 6 foot by 6 foot, 4 turns on each loop
Loops cut in asphalt SHALL be cut to a depth of 3 inches or deeper
Loops cut in concrete SHALL be cut 2.5 inches or deeper
Piezo Sensors shall be placed on one side of the lane and NOT placed in the middle of the lane

49. LAYOUT OF SENSORS
PIEZO
LOOP

50. LOOPS & LOOP INSTALLATIONS
Loops shall be installed as per FDOT Standards and Specifications
FDOT District 5 Standards REQUIRE that LOOPS ARE NOT TO BE SPLICED
Loop wires are to be checked prior to installation
Loops are to be placed in the BOTTOM of the slots

51. LOOPS & LOOP INSTALLATIONS
Insure there are not any scars, rips, insulation abrasions, or kinks in the wire assembly
All loops will be DRILLED in the corner using a 1.5 inch diameter bit
Make sure slots are clear of debris, rocks, and asphalt deposits
Verify depths are uniform throughout the entire cut

52. LOOPS & LOOP INSTALLATIONS
No loops shall be installed in WET asphalt or concrete
Do not apply sealants if roadway has residue or moisture in slots or on surface around cuts
A minimum of 2 inches of clearance from the top of the loop wire in the slot to the surface of the roadway is required

53. LOOPS & LOOP INSTALLATIONS
Loops shall be twisted a minimum of 6 to 12 turns per foot throughout the entire homerun length
Loops shall be marked in pull box and inside the cabinet
Homeruns shall be placed in the bottom of each cut

54. LOOPS & LOOP INSTALLATIONS
The homerun cut will start at 3 inches deep and for each additional homerun added to the slot and additional ½ inch will be cut to the depth
This process will allow for fewer homerun cuts to the roadway

55. PIEZO
LOOP
HOMERUN
CONDUIT
PULL BOX

56. LOOPS & LOOP INSTALLATIONS
We test all loops upon final inspection
We are checking the insulation, signal strength and circuit of the loops
We WILL NOT pass any loop that does no meet Entire Minimum Specifications

57. PIEZO INSTALLATIONS
Piezoelectric sensors most commonly used by FDOT are Measurement Specialties Incorporated (MSI) – BL Roadtrax
Sensors – BL is short for Brass Linguini

58. PIEZO INSTALLATIONS

59. PIEZO INSTALLATIONS
Piezoelectric systems use piezoelectric sensors. The sensors are embedded in a conducting material. When weight is applied the pressure changes the voltage of the electric charge flowing through the conductor. The sensors measure the change in voltage and calculate the load.

60. PIEZO SENSORS
The base technology is piezoelectric polymer. The Brass Linguini is a highly compressed piezoelectric polymer in a coaxial configuration, with brass outer casing.
The BL is flat, about 1/16” (1.5mm) thick and ¼ “ (7mm) wide. The sensors are put into the road in a ¾” (19mm) wide and 1.5” (25mm) deep slot cut in the road.

61. PIEZO SENSORS Installations
Piezo sensors are to be installed to Manufacture Specifications
All warranty cards and manufacture paperwork shall be left in the cabinet upon installation
All testing of sensors are to be performed in front of a Representative of the FDOT

62. PIEZO SENSORS Installations Epoxies to be used are as follows:
AS475: asphalt, modified mixes, superpave roadways
G100-EBOND: concrete
NO SPLICING OF PIEZO SENSORS
All piezo sensors MUST be marked in each pull box and inside of cabinet

63. PIEZO SENSORS Installations Re-test all piezo sensors in cabinet
***Piezo sensors shall be pushed down to .250 inches below surface of roadway*** This is a NEW application in FDOT Standards!!!

64. PULL BOX AND CONCRETE APRONS
Pull boxes may be made of Quazite material or concrete with a steel lid
All pull boxes must have locking bolts and screws
Each pull box is required to have a concrete apron that is 12 inches off each edge, 4 inches deep and slopes away to the surface around the pull box

65. PULL BOX AND CONCRETE APRONS
Pull boxes shall have a minimum of 8 inches of washed gravel inside of the base
All pull boxes shall have clearly marked cables and conduits

66. CABINETS All cabinets should meet the Specifications on the plans
All cabinets shall be mounted 48 inches off the ground measured to the handle of the cabinet to ground
The cabinet shall have proper grounding and grounding electrodes in place

67. IN-ROAD SENSOR TEMPLATES
The most common configuration used is the Loop-Piezo-Loop.
Piezo-Loop-Piezo configurations are also used in some scenarios.
WIM or Weigh in Motion sites most commonly use Piezo-Loop-Piezo configurations.

68. IN-ROAD SENSOR TEMPLATES
PTMS sites that collect volume and speed only by lane are made up of loop-loop configurations.
The type of sensors to be installed will be determined by the appropriate parties and placed in the design plans.

69. SITE LAYOUT AND MEASUREMENTS
Determine where the Piezo sensor will be placed in the lane.
Piezos are always laid perpendicular to the lane.
Mark the line with crayon or paint using a straight edge.
Add 6 inches to the length of the piezo to insure the length is correct.

70. SITE LAYOUT AND MEASUREMENTS
The piezo MUST BE located between the loops in the travel lane.
Measure upstream from the piezo 5 feet and mark this spot with crayon or paint.
Measure from the piezo 11 feet and mark with crayon or paint.
Using the center point we have already determined, we will now layout the loop.

71. SITE LAYOUT AND MEASUREMENTS
The loop is marked and painted.
Using a steel tape we will now measure 16 feet downstream and make a mark, this is the leading edge for the trailing loop. We will now measure 22 feet from the leading loop (this is 6 feet behind the mark we just made). We now have the second loop ready to mark and paint.

72. SITE LAYOUT AND MEASUREMENTS
We will use a straight edge that is at least 6 feet long to mark each leg of the loops.
A Laser may also be used to insure the loops are parallel in the lane.
We now have a loop-piezo-loop configuration.

73. SITE LAYOUT AND MEASUREMENTS
Check the loops from the stripe using a steel tape, each loop should be the same distance from the edge line or skip line, if not check the measurements and adjust until the distances are the same.
See diagrams for reference.

74. CONSTRUCTION CHECKLIST - PIEZOS
Type I or II
Cable length of piezo sensors
Approved Epoxy on Approved Products List
Depth of saw cut – 7/8” – 1.25” to 1.5”
Width of saw cut – ¾” – 7/8”

75. CONSTRUCTION CHECKLIST - PIEZOS
Piezo tested prior to installations
Warranty cards filled out completely
Slots clean of debris and water
Epoxy mixed to manufacturer’s standard
Duct tape applied to each side of piezo cut

76. CONSTRUCTION CHECKLIST - PIEZOS
Epoxy poured in several lifts or layers
Sensor cables at correct depth
Sensors retested after epoxy is applied
Manufacturer install sheets completed
Cables marked with lane of piezo

77. CONSTRUCTION CHECKLIST - LOOPS
Loops are corrected cut and corners drilled.
Loops are cut at correct depth
Loop wire is 12 gauge wire that is gasoline and oil resistant
Loop wire is placed into bottom of slot, no visible kinks or knots in wire

78. CONSTRUCTION CHECKLIST - LOOPS
Wire is applied with a blunt object (not a screwdriver, knife, etc.)
Loop wire is turned 4 times in grid
Loop wire is continuous with no splices in roadway
Loop slots are clean and compressed air used to blow out slots
Loop slots are dry

79. CONSTRUCTION CHECKLIST - LOOPS
Loop wire is placed in slot only when all saws and blowers are no longer in use
Loop wires are twisted at homerun junction – 6-12 twists per foot
Wire is re-inspected for cuts, nick, knots.

80. CONSTRUCTION CHECKLIST - LOOPS
Wire is placed into conduit and gently pulled to pull boxes.
Loop wires are marked in pull box and coiled with inches of excess wire
Wire is tested for inductance and continuity

81. CONSTRUCTION CHECKLIST – PULL BOXES
Pull box meets specification
Pull box is placed in solid ground
Pull box has correct depth of washed gravel
Pull box has a 5’ concrete pad surrounding it
Pull box is level and allows water to run off and not collect in or on pull box
Grass and aggregates are placed around pull box to prevent erosion

82. CONSTRUCTION CHECKLIST - CABINETS
Cabinet should meet Specifications
Cabinet should be securely anchored
Cabinet should be properly grounded
Cabinet should be mounted with the center of the cabinet at 48” from the ground
Cabinet should be facing away from the roadway

83. PTMS CHECKLIST Are piezo lengths correct? ______
Are piezo cables long enough to reach the cabinet? ______
Is the epoxy being used approved and mixed properly? ______
Is loop wire 12 gauge and gasoline and oil resistant? ______
Are loops located in the center of the lane? ______

84. PTMS CHECKLIST
Have piezos been checked prior to placement in road? ______
Has warranty card and paperwork been completed? ______
Is roadway clean and all equipment turned off before sensors installed? ______
Are saw cuts clean and is depth the same throughout entire loop/piezo? ______
Are corners of loops drilled with a 1 1/2” bit? ______

85. PTMS CHECKLIST
Do loop wires lay in bottom of slots without rise and falls? ______
Is loop wire twisted at homerun intersection? ______
Do loop wires have any kinks or cuts? ____
Is loop sealant applied evenly and covers all the slots? ______
Is the excess loop sealant removed from the roadway? ______

86. PTMS CHECKLIST Is epoxy mixed correctly? ______
Is epoxy on the APL list? ______
Was the piezo epoxy applied in layers? ___
Is epoxy cured and dry? ______
Is loop wire labeled? ______
Are pull boxes approved? ______
Are pull boxes correctly installed? ______
Washed gravel in pull boxes? ______

87. PTMS CHECKLIST
Did the contractor assign lane numbers inside the cabinet to piezos/loops? ______
Is cabinet level? ______
Is cabinet accessible? ______
Is the dirt and grass replaced? ______
Is dirt compacted to avoid erosion issues? ______
Are all dust, residue and compounds out of the roadway? ______

88. PTMS CHECKLIST
Is cabinet and grounding according to specifications? ______
Is conduit being used approved? ______
Are all schematic, paperwork, and warranty cards placed in cabinet? ______
Does cabinet lock and secure properly? ___

89. QUESTIONS?