621 Raised Pavement Markers (RPM)

Raised Pavement Markers – General

Materials (621.02)

Installation RPM Casting (621.04)

Documentation Requirements – 621 Raised Pavement Markers

 

Raised Pavement Markers – General

This information is intended to serve as a guide for construction personnel where the Contractor furnishes and installs raised pavement markers.  However, it may also be useful for maintenance personnel performing the same functions.  Inspection procedures are outlined.  This information points out the various important features and references the applicable specification or standard drawing.

Conduct 25 – 75% inspection during the installation activities which include daily start-up, intermittent, and end of day inspection.  Additionally, conduct 80 – 100% inspection of all installed RPM’s prior to final acceptance.

 

Materials (621.02)

Make sure that all RPM materials used on projects are approved and are listed on the Qualified Product List at the following web site:

Item 721.01 Raised Pavement Marker Castings

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=721.01

Item 721.02 Prismatic Reflectors

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=721.02

Item 721.03 Raised Pavement Marker Castings Adhesive

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=721.03

Item 721.04 Prismatic Reflectors Adhesive

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=721.04

 

 

Installation RPM Casting (621.04)

1.        References

a.        Brochure for RPM Installation Procedure

b.        See Traffic Engineering Manual, Section 350-3 at the following web site:

c.        http://www.dot.state.oh.us/Divisions/HighwayOps/Traffic/publications2/TEM/Documents/Part_03_071808_bookmarked.pdf

2.        RPMs shall be placed when the pavement surface temperature and the ambient air temperature are at least 40 °F (5 °C) and the pavement is dry.

3.        RPMs shall not placed under the following conditions:

a.        On pavement surfaces with cracking, spalling, or failure of underlying base material.

b.        Within 1 foot (0.3 m) of active signal detector loop wires.

c.        Over pavement markings except with the Engineer’s approval.

d.        Closer than 2 inches (50mm) to a pavement construction (transverse or longitudinal) joint or within an intersection.

e.        Within 3 feet (1 m) of a bridge expansion joint.

 

Brochure for RPM Installation Procedure

1.        Casting Installation

Typical Saw Cut

a.        Pavement must be cut to the dimensions for the casting being used.

2.        Casting in Saw Cut Without Epoxy

a.        Each pavement cut must be inspected prior to adding epoxy.

b.        When a casting is inserted in the cut without epoxy all 4 leveling lugs/tabs must contact the pavement surface.

All four keel-ends of castings must be below the surrounding pavement surface.

3.        Casting Centered in Saw Cut Lengthwise

a.        Each casting must be centered lengthwise and should have 1/8 inch (3 mm) clearance between pavement cut and casting for epoxy to bond properly.

b.        Only the leveling lugs/tabs should be in contact with pavement surface after insertion of casting in pavement so that minimum of 1/8 inches (3 mm) of epoxy is the bonding adhesive between casting and pavement.

c.        The pavement cut must be completely dry and free of dust, dirt or any other material that will interfere with the adhesive bond.

d.        Epoxy on the active reflector face must be removed immediately.

e.        Saw cut – casting fit must be periodically checked as saw blades wear to insure correct dimensions are maintained

4.        Properly Installed RPM with Epoxy Around Casting

a.        Two component epoxy adhesive approved, must be on QPL  is to be used to fill the pavement cut to within 3/8" of top of pavement cut, prior to placing casting.

b.        After placing casting:

The 4 leveling lugs/tabs must be in contact with pavement surface.

The epoxy should ooze out from under the casting from all sides filling all voids around the casting and be level with pavement surface.

RPM Lens Replacement

1.        References

a.        Brochure for RPM Installation Procedure

b.        See Traffic Engineering Manual Section 350-3 at the following web site:

c.        http://www.dot.state.oh.us/Divisions/HighwayOps/Traffic/publications2/TEM/Documents/Part_03_071808_bookmarked.pdf

2.        Remove Reflector

a.        Pry old reflector out of casting.

b.        Use eye protection when replacing reflector.

3.        Clean the casting:

a.        Scrape old pad material and adhesive out of reflector pocket, using an air hammer or wire brush.

b.        Sandblast the casting pocket to remove all residual adhesive, rust, and other contaminants.

c.        It is important that the casting is clean to ensure long-lasting performance.

4.        Apply Adhesive

a.        Peel the release liner from the back of the reflector.

b.        Apply a wide bead (approximately 3/8 inch) of an adhesive (as approved ODOT QPL) in the center of the adhesive pad on the back of the reflector.

5.        Install Reflector into Casting

a.        Place the reflector into the casting pocket.

b.        Apply foot pressure on the reflector for 1-3 seconds.

c.        Adhesive must flow out around all edges of the reflector to indicate that the adhesive completely covers the entire bottom of the reflector and provides a uniform adhesive layer between the reflector and the casting.

Remedial Actions for Poorly Installed RPM Castings

This information is intended to serve as a guide for construction and/or maintenance personnel where the RPM castings are poorly installed. Also, it provides a guide to the necessary remedial action to fix the problem.

The RPM casting shall be installed properly according to the following references:

1.        Item 621.03 “Layout”.

2.        Item 621.04 “Installation of RPM Casting”.

3.        Standard Construction Drawings TC-65.10 and TC-65.11.

The following information provides examples of defectively installed RPM castings and also describes remedial action to fix the problem:

Defective Installation: The RPM is installed with all four lugs/tabs not resting on the pavement such as shown in Figure 1 below:                  

new 23

Figure 1

Remedial Action:

Remove and reinstall the RPM casting at a new location.

New RPM location shall not exceed 25% of the specified RPM spacing.

If necessary to relocate the RPM to a distance greater than 25% of the RPM spacing, do not install the affected RPM. 

Fill the old cavity on the roadway surface with epoxy or asphalt concrete from where the RPM casting is removed.

Defective installation: The RPM is installed but does not fill the voids with epoxy all around the casting or the RPM is installed but the epoxy is not all around the casting to the surface of the pavement such as shown in Figure 2.

Figure 2

Remedial Action:

Blow out dirt from around casting with compressed air.

Fill the voids and seal the RPM casting all around with epoxy as shown in Figure 3.

DSC_0623

Figure 3

 Defective installation: The RPM casting is installed near or on a longitudinal joint or crack on the roadway surface such as shown in Figure 4.

Figure 4

Remedial Action:

Seal all the cracks with epoxy up to nine inches (225 mm) from the RPM casting as shown in Figures 5, 6 and 7.

DSC_0637

Figure 5

DSC_0646

Figure 6

DSC_0649

Figure 7

Defective installation: The RPM is installed but the epoxy adhesive is not hardened or the epoxy adhesive is not uniform gray in color such as shown in Figure 8.

Figure 8

Remedial Action:

Remove and reinstall the RPM casting at a new location.

New RPM location shall not exceed 25% of the specified RPM spacing.

If necessary to relocate the RPM to a distance greater than 25% of the RPM spacing, do not install the affected RPM. 

Fill the old cavity on the roadway surface with epoxy or asphalt concrete from where the RPM casting is removed.

Defective installation: The RPM is installed on construction joints which have extensive failure such as shown in Figure 9.

new 39

Figure 9

Remedial Action:

Remove and reinstall the RPM casting at a new location.

New RPM location shall not exceed 25% of the specified RPM spacing.

If necessary to relocate the RPM to a distance greater than 25% of the RPM spacing, do not install the affected RPM. 

Fill the old cavity on the roadway surface with epoxy or asphalt concrete from where the RPM casting is removed.

 

Documentation Requirements - 621 Raised Pavement Markers

1.        Verify castings to be used are on the Qualified Products List (QPL) before permitting installation.

2.        Verify the epoxy to be used to install the casting is on the Qualified Products List (QPL)

3.        Make sure that the keels of the casting are placed into the slots so that the tips of the RPM snowplow deflecting surfaces on the keels are below the pavement surface and all four lugs (Tabs) on the keels of the casting are in contact with the pavement.

4.        Check before placement of the epoxy, the saw cut is clean of all loose material and dry. Saw cut should have 1/8 inch (3 mm) clearance on all sides of the casting.

5.        Verify ambient air temperatures are at least 40 degrees Fahrenheit (5 degrees Centigrade) and the pavement is dry.

6.        Check epoxy is an A+B mixture, thoroughly mixed (grey color) and in accordance with manufacture’s recommendations.

7.        Check that sufficient epoxy is in and between the slots to ensure that all voids beneath and around the casting are filled.

8.        Placement of RPM castings shall be 6" (152 mm) from any construction joint (Lateral or Longitudinal).

9.        Location and / stations are per Standard Const. Drawing TC 65.10 and TC 65.11.

10.     Check quantity totals for payment.

11.     Document on CA-D-3B.

12.     Verify RPM reflectors to be used are on the Qualified Products List (QPL) before permitting installation.

13.     Verify the adhesive to be used to attach the reflector is on the Qualified Products List (QPL).

14.     Verify that all dirt, dust, oil, grease, rust, moisture, parts of damaged reflectors, or any foreign matter is removed that impairs adhesion of the reflector to the casting.

15.     Verify reflector area of the castings shall be sandblasted to 80% bare metal.

16.     Verify the application of adhesive is in a single bead, sufficient to squeeze out on all sides of the reflector when pressure is applied, to seat the reflector and seal out moisture.

17.     Document on CA-D-3B.