919.01 1006 SECTION 919 – PAVEMENT MARKING MATERIAL AND MARKERS
919.01 Thermoplastic Pavement Marking Material ............................... 1006
919.02 Spray Thermoplastic Pavement Marking Material ..................... 1010
919.03 Preformed Plastic Pavement Marking Materials ........................ 1012
919.04 Raised Refle ctive Pavement Markers ................................ ......... 1012
919.05 Snowplowable Reflective Pavement Markers ............................ 1012
919.01 Thermoplastic Pavement Marking Material
Provide material conform ing to AASHTO M 249, with the following additions.
A.Materials Provide retroreflective pavement marking material of an alkyd/maleic based thermoplastic material consisting of homogeneously mixed pigments, filler, resins , and glass beads. Ensure that the pigment, beads, and filler are uniformly dispersed in the resin. The mate rial shall be manufactured from virgin material using no reprocessed components. Ensure that t he material is free from all skins, dirt, and foreign objects , and conforms to the requirements specified in Table 919.01 -1. Table 919.01 -1: Thermoplastic Pavem ent Marking Material Component White Yellow Binder, % minimum 19 19 TiO2 Pigment, % minimum 10 N/A Intermix Glass Beads , % minimum 35 35 Calcium Carbonate/ Fillers, % maximum 36 (1) 46 (1)
1.The amount of Calcium Carbonate and inert fillers shall be as recommended by the manufacturer, provid ed all other specifications are met. 919.01 1007 Titanium d ioxide shall be Rutile Type II , conforming to ASTM D476 , with a minimum purity of 93%. The premixed beads s hall constitute the total silica content used in the formulation of the thermoplastic. Uniformly disperse the pigment, beads , and filler in the binder. The Alkyd/Maleic binder shall consist of a mixture of synthetic resins and high boiling point plasticize rs, one of which shall be solid at room temperature. At least one -half of the binder composition , and no less than 15% of the entire material formulation , shall be 100% maleic modified glycerol ester of resin. Do not use a binder contain ing any petroleum, hydrocarbon resins, tall oil resins , or rosins. Provide thermoplastic material meeting the following requirements:
1.The thermoplastic material shall be free of contaminates and shall be dry -blended or hot -mixed from 100% virgin stock using no reprocessed materials.
2.The thermoplastic material shall be formulated so that when it is on the roadway surface at any natural temperature , it will exist in a hard, solid state with cold ductility that allows normal movement with the road surface withou t chipping or cracking.
3.The thermoplastic shall not deteriorate or discolor when held at the application temperature for periods of time up to 4 hours or upon repeated reheating (a minimum of four times).
4.The color, viscosity, and chemical properties versus temperature characteristics of the thermoplastic material shall remain constant for up to 4 hours at the application temperature and shall be the same from batch to batch.
5.The thermoplastic material shall be readily applicable at temperatures be tween 400 °F and 440 °F from the approved equipment to produce lines and symbols of the specified thickness above the pavement surface.
B.Physical Requirements: After 4 hours @ 425 °F Ensure that t he thermoplastic material meets the physical requirements specified in AASHTO M 249, with the following changes . 919.01 1008 Test the material in accordance with AASHTO T 250 and/or with the appropriate method in Federal Test Method Standard #141 or ASTM Designation.
1.Bond Strength . 180 pounds per square inch, minimum, when tested in accordance with ASTM D4796.
2.Specific Gravity . Not to exceed 2.30 .
C.Glass Beads Provide glass beads that meet AASHTO M 247. Provide beads of clear, transparent, colorless glass, smooth and spherically shaped, free of milkiness, pits, or excessive air bubbles and that conform to the following specific requirements. Use glass beads contain ing no more than 200 parts per million of lead or 200 parts per million of arsenic. Certify and ensure that all glass beads meet all Federal requirements. Provide an independent test repor t certifying that all glass beads contain no more than 200 parts per million of arsenic or lead as determined by a certified independent (third party) laboratory, in accordance with Environmental Protection Agency testing methods 3 052, 6010B, or 6010C.
1.Color and Clarity. Beads shall be colorless, clear and free from carbon residues.
2.Roundness. Minimum true spheres overall shall be 80% when tested in accordance with ASTM D1155; for larger beads use visual inspection.
3.Index of Refra ction. Minimum of 1.50, when tested by the liquid emersion method at 77 °F
4.Air Inclusions. Maximum of 3% overall .
D.Intermix Glass Beads Premix glass beads into the thermoplastic mixture , to amount to 35% of the overall thermoplastic formulation. Use uncoated i ntermix beads 919.01 1009 defined by two distinct gradations and that meet the following requirements :
1.Type 1 Intermix glass beads shall make up at least 50% of 35% of the overall thermoplastic formulation (Intermix Glass Beads) and shall conform to AASHTO M 247, Type 1 , with the exception that the minimum true spheres overall shall be 80% as specified in 919.01.C.2 .
2.Type 3 Intermi x glass beads shall make up at least 50 % of 35% of the overall thermoplast ic formulation (Intermix Glass Beads) and shall conform to AASHTO M 247, Type 3 with the exception that the minimum true spheres overall shall be 80% as specified in 919.01.C.2 .
E.Double Drop System The double drop system shall be capable of applying glass beads at the specified application rates. Apply beads across the entire line width , ensuring uniform application and embedment of the beads to 50 to 60% of the bead diameter. Use Type 1 drop on beads that are dual-coated for moisture resistance and adhesi on and that meet the requirements of AASHTO M 247 Type 1 with the exception that the beads shall be 80% round overall. Use Type 4 drop on beads that are dual-coated for moisture resistance and adhesion and that meet the requirements of AASHTO M 247 Type 4 with the exception that the beads shall be 80% round overall.
F.Marking Compound. Use material having the following characteristics:
1.In the molten state, the material shall not give off fumes that are toxic or otherwise injurious to person s or property. Obtain material safety data sheets for the product from the manufacturer.
2.The temperature versus viscosity characteristic of the plastic material shall remain constant. In addition, the material shall not deteriorate in any manner duri ng three reheating processes.
3.No obvious change in material color shall occur as a result of up to three reheatings, or in maintaining the material at application 919.02 1010 temperature up to an aggregate time of 4 hours, or from batch to batch.
4.The maximum elapsed time after application at w hich normal traffic will leave no impression or imprint on the new pavement marking shall be 30 seconds when the air and road surface temperature is approximately 68 °F plus or minus 5 °F.
5.The applied pavement marking shall remain free from tack, and shall not lift from the pavement under normal traffic conditions, within a road temperature range of -20 ° to 150 °F.
6.The pavement marking shall maintain its original dimensions and placement.
7.Cold ductility of the material shall allow for normal di mensional distortion as a result of tall impact within the temperature range specified.
8.The material shall provide a pavement marking that has a uniform thickness throughout its cross -section.
919.02 Spray Thermoplastic Pavement Marking Material
Provide retroreflective pavement marking material that meets the requirements specified in 919.01, except as noted below.
A.Materials Spray thermoplastic pavement marking material shall conform to the requirements specified in Table 919.02 -1. 919.02 1011 Table 919.02 -1: Spray Thermoplastic Pavement Marking Material Component White Yellow Binder, % min 26 26 TiO2 Pigment, % min 10 N/A Intermix Glass Beads , % min 35 35 Calcium Carbonate/ Fillers, % max 29 (1) 29 (1)
1.The amount of Calcium Carbonate and inert fillers shall be as recommended by the manufacturer, provid ed all other specifications are met. Requirement 919.01.A.5 does not apply.
B.Physical Requirements: After 4 Hours at 425 °F Ensure that the thermoplastic material, after being heated for 4 hours plus or minus 5 minutes at 425 plus or minus 3 °F and cooled to 77 plus or minus 3 °F, meets the physical requirements set forth in AASH TO M 249, with the following changes. Test the material in accordance with AASHTO T 250.
1.Specific Gravity. 2.0 maximum
2.Softening Point. After heating the marking compound for 4 hours plus or minus 5 minutes at 425 plus or minus 3 °F and testing in accordance with ASTM E28, the material shall have a minimum softening point of 180 °F as measured by the ring and ball method.
C.Glass Beads Use beads conforming to AASHTO M 247, Type 1.
D.Intermix Glass Beads. Premix Type 1 glass beads for intermix into the thermoplastic mixture, to amount to 35% of the overall thermoplastic formulation.
E.Drop on Glass Beads. Use drop on glass beads that may be applied at the specified application rates and that can flow freely through dispensing equipment in any weather suit able for pavement marking 919.03 1012 application. Apply Type 1 beads at a minimum application rate of 10 pounds per 100 square feet. Apply beads across the entire line width, ensuring uniform application and embedment of the beads to 50 to 60% of the bead diameter. Treat Type I drop -on glass beads with a moisture resistant coating.
F.Marking Compound Use marking compound conforming to 919.01.F.
919.03 Preformed Plastic Pavement Marking Materials
Provide preformed plastic pavement marking material selected from the Department’s QPL.
919.04 Raised Reflective Pavement Markers
Provide raised reflective pavement markers listed on the Department’s QPL and classified a s follows: Type 1 One-Color, Reflective Markers (Two -way Traffic) Type 2 One-Color, Reflective Markers (One -Way Traffic) Type 3 Two-Color, Reflective Markers (One -way Traffic)
919.05 Snowplowable Reflective Pavement Markers
Provide reflectors consisting of an acrylic shell filled with tightly adherent potting compound. Select the potting compound based on strength, resilience, and adhesion adequate to pass the necessary physical requirements. The shell shal l contain one or two reflective faces. Attach the reflector to an iron casting with an elastomeric pad. Provide reflectors and castings selected from the Department’s QPL and that conform to the following requirements.
A.Reflectors
1.Dimensions. Provide refl ectors that are 4 plus or minus 0.5 inches by 2.0 plus or minus 0.25 inches at the base, with a height of 0.40 inch or no higher than 0.50 inch. The slope of the reflector shall be 30 degrees, and the minimum area of the reflective surface shall be 1.87 square inches. 919.05 1013 2. Outer Surface. Provide the shell with a smooth outer surface, except as needed for identification purposes.
3.Base Surface. Ensure that the base of the marker is substantially free from gloss or substances that may reduce its bond to adhesive . Attach the markers, either mono - or bi-directional as specified, to an iron casting that is shaped to be snow plowable in the two opposing longitudinal directions and designed to allow for removal and replacement when needed to restore reflectivity.
B.Castings
1.General. Provide casting that are 10 plus or minus 0.5 inches long by 5.5 plus or minus 0.5 inches wide. Ensure that the maximum projection of the casting above the roadway does not exceed 0.5 inch, and that snowplow blades will ride over the casti ng without contacting the reflective marker.
2.Casting Material. Provide castings of nodular iron conforming to ASTM A536, Grade 72 -45-05, hardened to 52 -54 RC.
3.Identification. Mark each casting with manufacturer’s name and model number of marker. 920.01 1014 SECTION 920 – EROSION CONTROL MATERIALS
920.01 Erosion Control Blankets ................................ ........................... 1014
920.02 Staples ................................ ................................ ........................ 1014
920.01 Erosion Control Blankets
Provide erosion control blankets selected from the Department’s QPL.
920.02 Staples
Use wire not smaller t han 11 gauge, formed into a U shape with legs at least 6 inches in length and a crown 1 inch in width. Ensure that staples have sufficient thickness to penetrate the soil without undue distortion.
Source: Tennessee Standard Specifications for Road and Bridge Construction, 2021 Edition. Pages 1015–1022 of 1,072.