3592Drop-On Glass Beads

3592.1SCOPE

Provide treated glass beads for retroreflectorizing liquid pavement markings.

3592.2REQUIREMENTS

Provide treated glass beads meeting AASHTO M 247 Standard Specification for Glass Beads Used in Pavement Markings, with the following characteristics and requirements: A General Requirements

B Gradation and Roundness Requirements B.1 Standard Gradation Meet the requirements of AASHTO M 247, Type 1 except with at least 80 percent true spheres. B.2 “Utah Blend” Gradation Meet the graduation requirements of Table 3592.2-1 and at least 80 percent true spheres for beads passing the No. 30 Sieve. Table 3592.2-1 Utah Blend Gradation Requirements Sieve Size Percent Passing No. 18 65-80 No. 30 30-50 No. 50 0-5 C Coating Requirements C.1 Dual Coated Beads Provide beads with dual surface treatment meeting the following requirements and characteristics for use with water-based paints:

AASHTO M 247 and AASHTO T346 Standard Method of Test for Glass Beads Used in Pavement Markings, as recommended by the paint manufacturer

manufacturer

T346 C.2 Moisture Resistant Coated Beads Provide beads for use with multi-component liquid with a moisture resistant silicone surface treatment meeting the requirements of AASHTO M 247 and T346 as recommended by the multi-component liquid manufacturer. D Packaging Requirements Unless otherwise specified, provide beads packaged in moisture-proof, multi-wall shipping bags, and in containers marked with the following information:

Deliver the containers and contents in a dry condition. The Engineer will reject beads not meeting the requirements of this Specification.

3592.3SAMPLING AND TESTING

Provide samples in the rates and sizes meeting the requirements of the Schedule for Materials Control and as required by the Contract. The Engineer will test in accordance with AASHTO M 247, except the Engineer will determine roundness meeting the requirements detailed in the Laboratory Manual.

Stone and Brick