9-168 Section 920. Permanent Pavement Marking Materials
920.01 Marking Materials
Select pavement marking materials from the Qualified Products List . When selecting preformed thermoplastic produc ts, ensure that preformed thermoplastic materials have a thickness of 90 mils for surface applications and a thickness of 125 mils for recessed applic ations. For black liquid shadow markings and blue markings used in parking areas, choose a specified binder material and color from the Qualified Products List or select a white specified binder material from the Qualified Products List and tint the product to the appropriate color. Use liquid applied pavement marking materials manufactured in the previous 12 months or within the shelf life directed by the manufacturer, whichever is less. Use solid applied materials within the shelf life directed by the manufacturer . Provide certification that liquid and solid applied pavement marking materials have been stored per the manufacturer ’s requirements . Materials not in compliance will be rejected and removed at the Contractor ’s expense.
A.General Packaging and Lab eling. Material containers or packages must be marked on the tops and sides using a durable, weather -resistant marking . Include the following information:
1.Manufacturer ’s name and address ;
2.Description of the material ;
3.Product identification number ;
4.Lot or b atch number ;
5.Date of manufacture;
6.Volume; and
7.Weight.
B.Packaging and Labeling for Cold Plastic and Thermoplastic Markings
1.Cold Plastic . Containers or packages of cold plastic material and the core of each rol l must be marked with the information specified in subsection 920.01.A.
2.Thermoplastic . In addition to the requirements of subsection
920.01 A, thermoplastic material must be packaged in non-stick
MDOT Standard Specifications for Construction Section 920 9-169 containers and labeled with “heat to manufacturer -recommended temperature range. ”
920.02 Glass Beads and Wet Reflective Optics
A.Packaging and Labeling . Package g lass beads and wet reflective optics in moisture-resistant bags and label with the following information:
1.Manufacturer ’s name and address ;
2.Shipping point ;
3.Trademark or name;
4.The wording “ Glass Beads ” or “Optics ”;
5.Specification number ;
6.Weight ;
7.Lot or b atch number; and
8.Date of manufacture. Drop-on AASHTO M247 Type I beads are herein referred to as standard glass beads . Large glass beads must meet federal specification TTB-1325 for a Type 4 glass bead. All glass beads and wet reflective optics to be used on Federal -aid projects must contain no more than 200 parts per million of arsenic or lead, as determined in accordance with Environmental Protection Agency testing methods 3052, 6010B, or 6010C.
B.General Requirements for Standard Glass Beads. Standard glass beads must meet the physical characteristics and gradation requirements specified in Table 920-1 unless otherwise specified in subsection
920.02 D for specific applications.
Table 920- 1: General Requirements for Standard Glass Bead : Physical C haracteristics (MTM 711) Characteristic Requirement General appearance Transparent, clean, smooth, free from milkiness, pits, or excessive air bubbles Shape Spherical with ≥75% true spheres Color Colorless, very light gray, very light gray tinge, or bright white Index of refraction ≥1.50 Alkalinity ≤2.0 MDOT Standard Specifications for Construction Section 920 9-170 Table 920- 2: Gradation Requirements (MTM 711) Sieve Size (No.) Total % Passing 20 100 30 75–95 50 15–35 100 0–5
C.General Requirements for Wet Reflective Optics. Select wet reflective optics from the Qualified Products List or a Department -approved alternative that meet s or exceeds the retroreflectivity requirements specified in Table 920-2 . Prior to application, submit certification from the wet reflective optics manufacturer that when applied according to the manufacturer ’s application recommendations , the wet reflective optics meet the requirements in Table 920-2 . Table 920- 3: General Wet Reflective Optic Requirements: Average Initial Retroreflectivity at 30- meter G eometry in mcd/lux/m2 Test Method Color White Yellow Dry (ASTM E1710) 700 500 Wet recovery (ASTM E2177) 250 200 Wet continuous (ASTM E2832) 100 75
D.Standard Glass Bead and Wet Reflective Optic Requirements for Specific Applications
1.For recessed longitudinal markings, use a double-drop system of large and standard glass beads, a double-drop system of wet reflective optics and standard glass beads, or an Engineer -approved alternat ive. Ensure that large glass beads meet federal specification TTB -1325 for a Type 4 glass bead.
2.Waterborne and Low -Temperature Waterborne. Standard and large glass beads for use with waterborne marking material and low-temperature waterborne marking material require a moisture -resistant coating and a silane coating. The type, gradation, and application rates for wet reflective optics used with waterborne and low -temperature waterborne marking materials must meet the waterborne manufacturer ’s recommendat ions.
3.Regular Dry . Standard and large glass beads for use with regular dry marking material may have a moisture-resistant coating, a silane MDOT Standard Specifications for Construction Section 920 9-171 coating, or both. The type, gradation, and application rates for wet reflective optics used with regular dry marking materials must meet the regular dry manufacturer ’s recommendations.
4.Thermoplastic . Standard and large glass beads for thermoplastic marking material must have a moisture-resistant coating. The type, gradation, and application rates for wet reflective optics used with thermoplastic marking materials must meet the thermoplastic manufacturer ’s recommendations.
5.Sprayable Thermoplastic . The type, gradation, and application rates for all standard and large glass beads and wet reflective optics used with sprayable thermoplastic marking material must meet the sprayable thermoplastic manufacturer ’s recommendation.
6.Polyurea. The type, gradation, and application rates for all standard and large glass beads and wet reflective optics used with polyurea marking material must meet the polyurea manufacturer ’s recommendation.
7.Modified Epoxy . The type, gradation, and application rates for all standard and large glass beads and wet reflective optics used with modified epoxy marking material must meet the modified epoxy manufacturer ’s recommendation.
Source: Michigan Standard Specifications for Construction, 2020 Edition. Pages 978–981 of 1,146.