AASHTO M 249 White and Yellow Reflective Thermoplastic Striped Material (Solid Form)

The “ AASHTO M 249 White and yellow reflective thermoplastic striping material (solid form)” standard, published by the American Association of Highway and Transportation Authorities (AASHTO) , covers reflective thermoplastic pavement striping material applied to the road surface by mechanically melting glass beads onto the surface at a rate specified by the buyer or manufacturer. When the applied thermoplastic is cooled to normal pavement temperature, it produces an adhesive retroreflective strip of the specified color, thickness, and width that is resistant to deformation by traffic.

Thermoplastic material is composed of a homogeneous mixture of pigment, filler, resin, and glass reflective spheres. The thermoplastic material is available in both white and yellow. The resin is either alkyd or hydrocarbon, as specified by the purifier. The supplier has the option of formulating the material to their own specifications. However, the physical and chemical properties in this specification apply regardless of the type of formulation used.

Glass beads (premix) must be lead-free and formulated according to AASHTO M 247 standard, Type I. The yellow pigment must be free of lead and lead-chromate.

The specific gravity of the white and yellow thermoplastic traffic line material should not exceed 2,15.

The pigment, beads, and filler must be evenly dispersed throughout the resin. The material must be free of all scale, dirt, and foreign matter and must conform to the requirements in the table provided in the standard.

The thermoplastic material must meet the values ​​given in the standard after being heated to 218 degrees plus/minus 2 degrees for 240 minutes plus/minus 5 minutes and cooled to 25 degrees plus/minus 2 degrees.

The AASHTO M 249 standard specifies requirements for reflective thermoplastic road stripe materials used on road surfaces to enhance visibility and ensure durability in traffic conditions. This standard specifies the properties, application methods, and test procedures for white and yellow thermoplastic stripe materials.

The AASHTO M 249 standard covers reflective thermoplastic road strip material applied in a molten state to road surfaces by mechanical means. Glass beads are incorporated into the surface at a ratio specified by the purchaser or manufacturer to provide retroreflective properties that enhance visibility, particularly at night or in adverse weather conditions. When the material cools to normal road temperature, it forms an adhesive, reflective strip of a specified color (white or yellow), thickness, and width, resistant to traffic-induced deformation.

This standard specifies the composition of the thermoplastic material and generally includes:

• Binder: A resin that holds the material together and allows it to adhere to the coating.
• Pigments: Provides white or yellow color, meeting specific color requirements for visibility and consistency.
• Glass beads: Embedded in the material to provide retroreflective properties, making the stripes visible in low-light conditions.
• Fillers: Such as calcium carbonate or other aggregates that contribute to the strength and structural integrity of the material.

The material must meet certain physical and chemical properties to ensure it will perform under varying environmental and traffic conditions.

The AASHTO M 249 standard outlines several performance criteria, including:

• Adhesion: The material must adhere firmly to asphalt or concrete surfaces.
• Durability: The strip must be resistant to deformation over time and wear from traffic.
• Retroreflection: The addition of glass beads ensures that the strip effectively reflects light and meets minimum retroreflection standards.
• Color stability: White and yellow colors should remain consistent and not fade prematurely when exposed to sunlight and weather conditions.

The thermoplastic material is typically applied in the molten state at temperatures between 204°C and 232°C. The standard specifies:

• Application method: Mechanical application such as extrusion or spraying to achieve uniform thickness and width.
• Glass bead application: Glass beads are applied at a specific rate to ensure consistent retroreflection across the strip.
• Cooling time: The material must solidify quickly after cooling to form a durable, traffic-resistant strip.

The AASHTO M 249 standard refers to various standards to ensure comprehensive testing and quality control:

• The standard “AASHTO M 247 Standard Specification for Glass Beads Used in Road Markings” regulates the quality and properties of glass beads.
• The standard, “AASHTO T 250 Standard test method for thermoplastic traffic marking material,” outlines procedures for testing the properties of the material.
• The standard “ASTM D36/D36M Standard test method for softening point of bitumen” is used to determine the softening point of thermoplastic material.
• The standard “ASTM E1710 Standard test method for measuring retroreflective road marking materials” ensures that the material meets the retroreflective requirements.
• “FED-STD-141 Methods of testing physical and chemical properties of paint and related materials” standard.

The AASHTO M 249 standard includes prequalification requirements to ensure that materials meet performance criteria before they can be widely used. These briefly cover:

• Sampling methods to obtain representative test samples.
• Preparation of test samples.
• Evaluation of physical properties such as softening point, hardness and retroreflection.

The AASHTO M 249 standard is considered important because it directly impacts road safety, durability, and consistency in road markings. The primary reasons for its importance are as follows:

• Improves road safety: This standard requires white and yellow thermoplastic stripe materials to be highly reflective thanks to embedded glass beads. This retroreflective property improves visibility in low-light conditions, such as at night or in adverse weather conditions, helping drivers stay in their lanes and avoid accidents.
• Ensures durability: This standard specifies requirements for adhesion and resistance to abrasion from traffic and environmental factors. This durability ensures that road markings remain durable and effective for longer, reducing costly maintenance and repainting.
• Promotes consistency: By providing clear guidelines for material composition, application methods, and performance testing, the standard ensures uniformity in road markings across regions and jurisdictions. Consistent markings help drivers reliably interpret road markings and lanes regardless of location.
• Supports infrastructure efficiency: This standard's rigorous testing and prequalification processes ensure high-quality materials, reducing the likelihood of premature failures that could disrupt traffic or require unexpected repairs. This contributes to cost-effective road maintenance.
• Simplifies compliance: Transportation agencies and contractors rely on this standard to meet federal and state requirements for road markings and ensure compliance with safety regulations and industry best practices.

As a result, the AASHTO M 249 standard is critical for creating safe, durable, and standardized road markings that increase driver safety and support efficient transportation infrastructure.

Our organization, which has been serving for many years and meticulously following global developments in science and technology, employs a team of experienced professionals and a broad infrastructure to conduct testing, measurement, and analysis in a wide range of areas for businesses across all sectors. In this context, we also provide testing services in accordance with the "AASHTO M 249 White and yellow reflective thermoplastic striped material (solid form)" standard.