PREFORMED THERMOPLASTIC PAVEMENT MARKINGS
Preformed thermoplastic is a pavement marking material applied to the roadway surface typically by heating torches. Preformed thermoplastics are used as striping material, symbols and legends on the pavement surface including stop bars, arrows, pavement signs and text markings.
Preformed thermoplastic shall meet the following requirements:
Binder Content – 18% Minimum
Glass Beads – 30% Minimum
Bond Strength (ASTM 4796) 200 psi Minimum
Skid Resistance (ASTM E 303) 45 BPN Minimum
The color shall stay in the chromaticity box for standard highway colors (upon initial installation).
Thickness shall be as specified. (Typically 90 mils or 125 mils)
Reflectivity (upon initial installation): mcd/sq m/lux
300 Minimum White
200 Minimum Yellow
Installation of preformed thermoplastic pavement markings shall be as required by the product manufacturer (Additional bead drops may be necessary to meet Reflectivity requirements). Improper heating of the thermoplastic can affect initial reflectivity readings, care should be taken to closely follow manufacturer installation requirements. Utilization of primers may be required for proper installation on pavement surfaces and shall be used as recommended by the manufacturer.
The Preformed Thermoplastic Pavement Marking Material must be produced in the United States and the manufacturer shall be ISO 9001:2015 certified. Shelf life of preformed thermoplastics is typically less than 1 year when stored in amicable conditions therefore preformed thermoplastics should be applied to the pavement within 10 months of manufacture or placement of preformed thermoplastic pavement markings shall be within the manufacturers published shelf life for the material.
MANUFACTURER / BRAND NAME APPROVAL
Request for approval shall be made to the Construction and Materials Bureau in Ames, Iowa. This shall include a complete product description, instructions for application, technical data sheet, recommended usage and NTPEP test deck data. A sample of at least 5 feet of 4 inch wide preformed thermoplastic of each color shall be furnished to the Construction and Materials Bureau at the Iowa Department of Transportation, 800 Lincoln Way, Ames Iowa, 50010.
If NTPEP test deck data for the product is not available at the time of initial application for approval the preformed thermoplastic products shall be submitted to the National Transportation Product Evaluation Program (NTPEP) test deck for evaluation and once data is acquired shall be submitted for review. Probationary approval of a preformed thermoplastic may be allowed pursuant to submittal to NTPEP along with sufficient performance data and/or proven performance in the field of the product being submitted as determined by the Construction and Materials Bureau.
Preformed thermoplastic markings shall be evaluated pursuant to the NTPEP work plan for field and laboratory evaluation of preformed thermoplastics.
Approval of preformed thermoplastic markings may be withdrawn because of deficient test results on samples; product changes made after the original qualification, or unsatisfactory field performance. Samples of the preformed thermoplastic on which a qualification was based will be used as the standards for comparison with preformed thermoplastics supplied to projects.
The Construction and Materials Bureau may sample and test the preformed thermoplastic to verify compliance with specifications. Such samples will be a continuous section as typically supplied by the manufacturer.
Acceptance of initial Preformed thermoplastic material supplied for a project shall be based on approved manufacturer and approved Brand Name. Approved manufacturers and Brand Names are listed in the Materials Approved Products Listing Enterprise (MAPLE).