554 THERMOPLASTIC PAVEMENT MARKINGS
From MDOT Policy Manual
- Furnish and apply thermoplastic pavement marking material to roadway surfaces as specified and as directed.
- Thermoplastic is a durable material. Select thermoplastic pavement markings from the Qualified Products List (QPLQualified Products List Award—The decision by a procurement agency to execute a purchase agreement or Contract after all necessary approvals have been obtained.).
- Refer to 549.03.
- 554.03.01 Quality Control. Refer to 549.03.01.
- 554.03.02 Quality Assurance. Refer to 549.03.02.
- 554.03.03 Cleaning Pavement Surfaces. Refer to 549.03.07.
- 554.03.04 Quality Control Test Strip. Refer to 549.03.09.
- 554.03.05 Application EquipmentAll machinery, tools, and apparatus necessary for the proper construction and acceptable completion of the work, together with the necessary supplies for upkeep and maintenance..
- (a) Kettles. Use equipment that has oil or air jacketed kettles for uniform melting and heating of the thermoplastic material, is equipped with an automatic thermostatic device to provide positive temperature control, and conforms to the requirements of the National BoardThe Board of Public Works of the State of Maryland. of Fire Underwriters (NBFUNational Board of Fire Underwriters), the National Fire Protection Association (NFPANational Fire Protection Association), and State and local authorities.
- (b) Agitation. Use equipment that provides continuous mixing and agitation of the material in the kettle, constructed so that all mixing and conveying parts, (including the application apparatus) maintains the material at the specified temperature and constructed to prevent clogging of the applicator conveying parts between the reservoir and the application apparatus.
- (c) Capacity. Use vehicle mounted equipment capable of holding a minimum of 600 lb of molten thermoplastic material for longitudinal line application.
- (d) Temperature Gauges. Use temperature gauges that have been calibrated every six months and submit a copy of the calibration certification per the QCP.
- (e) Footage Counters. Use calibrated footage counters to measure pavement markings and submit notarized calibration certification per the QCP.
- (f) Usage Counters. Use equipment that is equipped with material usage counters and printers or measure tanks manually using equipment manufacturer certified tables. Use beginning and ending quantities to calculate thickness of applied lines and record daily.
- (g) Bead Dispenser. Use a pressurized bead dispenser or other mechanical conveying method not dependent upon gravity for uniform application of glass beads for each material dispenser.
- (h) Material Dispenser. Use a material dispenser that is capable of applying all longitudinal markings at multiple width settings ranging from 5 to 12 in. as demonstrated by the quality control strip and as specified. Reconduct the quality control strip whenever the guns are repositioned or adjusted after the initial quality control strip.
- (i) Maneuverability. Use a vehicle that is mobile and maneuverable to produce straight lines, standard curves in true arcs, and capable of cleanly cutting off the ends of markings.
- (j) Cleanliness. Thoroughly clean all parts of the equipment of foreign or different colored material prior to the introduction of a new batch of material.
- 554.03.06 Application. Use vehicle mounted equipment to apply markings at the location, width, and type of marking specified and as directed. Apply to bare pavement or over exsiting thermoplastic per the manufacturer’s recommendations. Do not place thermoplastic material over longitudinal joints; offset 2 in. or as directed.
- Use small equipment capable of heating, agitation and applying glass beads to apply thermoplastic markings to gore areas, crosswalks, small intersections, roundabouts, wide markings, transverse markings and other areas that preclude the use of vehicle mounted equipment.
- (a) Ambient Conditions. Apply material when ambient and surface temperatures are at least 50 F and rising at the time of application.
- (b) Moisture in Pavement. MSMT 729. Do not apply material if test is positive for moisture.
- (c) Temperature. Apply thermoplastic material when the molten material temperature is between 400 and 440 F unless otherwise recommended by the manufacturer, and approved.
- (d) Primer. Use a primer that is compatible with the thermoplastic material and recommended by the thermoplastic manufacturer when thermoplastic material is applied to portland cement concrete surfaces.
- (e) Thickness. MSMT 729. The pavement markings shall yield a solid of 90 mils above the roadway surface. Variation from this range will be used for the price adjustment specified herein.
- (f) Glass Beads. MSMT 729. Apply standard glass beads to the surface of the molten thermoplastic at the minimum rate of 7 to 9 lb/100 ft2.
- (g) Color. MSMT 729.
- (h) Retroreflectance. MSMT 729. The minimum retroreflectance shall be 150 millicandelas/lux/square meter for yellow and 250 millicandelas/lux/square meter for white.
- (i) Widths. Refer to 549.03.04.
- (j) Alignment. Refer to 549.03.05.
- (k) Layout Markings. Refer to 549.03.06.
- 554.03.07 Curing. Refer to 549.03.10.
- 554.03.08 Observation Period. Refer to 549.03.11.
- 554.03.09 Submittals. Supply MSDS, Product Data Sheets, and QCPs.
554.04 MEASUREMENT AND PAYMENT.
- Refer to 549.04. Payment will be full compensation for all pavement preparation, furnishing and placing of markings, testing, and for all material, labor, equipment, tools, and incidentals necessary to complete the work.
- Thermoplastic Pavement Marking lines will be measured and paid for at the Contract unit price per linear foot for the color and width specified.
- Thermoplastic Pavement Marking Legends (letters and numbers) and Symbols will be paid for at the Contract unit price per square feet.
- 554.04.01 Price Adjustment for Film Thickness. The unit price for Thermoplastic Pavement Markings will be per striped linear foot based on MSMT 729 calculations for thickness, and will be adjusted in conformance with the following:
MIL THICKNESS* PERCENT OF PAYMENT - UNIT PRICE 90- (a)(b) 100 80-89 90 70-89 80 Less than 70 Retrace to achieve a thickness of 90 mils.
- (a) The EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. may require the removal of excess material thickness.
- (b) Removal of excess material and retracing pavement markings shall be performed at no additional cost to the AdministrationShall mean any one of the Administrations within the Maryland Department of Transportation, as listed in GP 1.02..
- *Material thickness less glass bead allowance.