626Thermoplastic Traffic Markings

626.01 Description. This work consists of furnishing materials and placing thermoplastic

pavement markings of the type specified in reasonably close conformity with these specifications and the details shown on the plans or established. All pavement marking material, excluding edge lines over rumble strips, shall be applied using the extrusion/ribbon method. Edge lines placed over rumble strips shall be applied using the atomization/spray method. Cold plastic traffic markings may be used in lieu of hot applied thermoplastic markings. Substitution will only be allowed for pay items 626-A through H. Substituted cold plastic markings shall be of the same color and width as that required for the hot applied stripe. Unless otherwise specified, the markings, whether hot applied or cold plastic, shall be of the same type of material for the entire project. Material and construction requirements for substituted cold plastic traffic markings shall meet the requirements of Section 628 of the Standard Specifications. The layout and spacing for substituted cold plastic traffic markings will remain as shown in the plans, or in the contract documents, for hot applied thermoplastic markings. Measurement of substituted cold plastic traffic markings shall be made in accordance with Section 628 of the Standard Specifications. Payment for substituted cold plastic traffic markings shall be made at the unit price for the appropriate hot applied thermoplastic marking.

626.02 Materials. The Department reserves the right to perform additional testing of

thermoplastic traffic marking materials at an y time. Upon request of the State Materials Engineer, samples of the thermoplastic compound, glass beads and epoxy resin shall be furnished. Blue - ADA thermoplastic marking material shall meet the requirements of Subsection

720.02 with the exception that the color shall be blue-ADA. In lieu of the above material

requirements, the Contractor may use hot a pplied thermoplastic materials meeting the satisfaction of the Engineer.

626.02.1 Thermoplastic Material. Thermoplastic material shall meet the requirements

of Subsection 720.02, except an alkyd resin shall be used in the formulation when used in construction of stop lines, crosswalks, and legends.

626.02.2 Glass Beads. Glass beads shall meet the requirements of Subsection 720.01.

Unless otherwise noted, Class A glass beads shall be used.

626.03 Construction Requirements.

626.03.1 Thermoplastic Traffic Stripe.

626.03.1 1--Equipment. Equipment for hot application shall be of sufficient size and

stability to ensure smooth, uniform, properly aligned markings of the dimensions specified. The application equipment shall be capable of automatic placement of intermittent and continuous line patterns in single or double line applications simultaneously. The intermittent timer mechanism shall provide a variable ratio of materials applied and variable cycle length such that accurate placement of new patterns, or replacement of existing patterns can be achieved. When edge lines are placed over rumble strips , the equipment must be able to apply the marking material using the atomization/spray method instead of extrusion/ribbon method. To ensure the proper alignment of the rumble stripes, the Contractor will be required to place a layout line to be followed during inst allation of the edge lines over the rumble strips. The equipment shall also be capable of applying the top dressing of glass beads in a manner that firmly embeds them into the surface of the thermoplastic material for at least one half of the diameter of the larger gradation sizes of the beads. The dispensing equipment shall be equipped with an automatic cut-off control for the application of the beads that is synchronized with the cut-off of the thermoplastic material.

626.03.1 2--Construction Details. Application of thermoplastic material shall be made

only in periods of dry weather and when the temperature of the pavement surface is at least 55°F. The pavement shall be surface dry, to the satisfaction of the Engineer, before application will be permitted. The application temperature of the thermoplastic material shall be between 400° and 450°F. Upon request, the Engineer will establish the control points for ma rkings at necessary intervals not to exceed 600 feet on tangents and more often on curves. All additional work necessary to establish intermediate control points shall be performed by the Contractor. On curves, unsightly variations from the normal curvature will not be permitted unless specifically shown on the plans or ordered by the Engineer. Immediately before application, the areas to receive markings shall be cleaned thoroughly in accordance with Subsection 625.03.2. On areas of pavement cured with compound, the membrane shall be removed completely by shot blasting, sand blasting or other approved method. Unless otherwise directed by the Engineer, tr affic stripes that are coincidental with the thermoplastic stripe shall be removed prior to placement of the thermoplastic material, except that temporary paint stripe may be left in place when satisfactorily placed in the proper location. Any temporary stripe not covered shall be removed. Payment for removal of stripe, except temporary stripe, will be made under Section 202. When thermoplastic material is to be applie d to concrete pavements or bridge surfaces, a binder-sealer of the type and amount recommended by the manufacturer of the thermoplastic material shall be applied prior to placement of the thermoplastic material. On other pavement surfaces, a binder-sealer shall be applied under those conditions recommended by the manufacturer of the thermoplastic material. The thickness of the thermoplastic material, when measured above the surface plane of the pavement, shall be within tolerance of the specified thickness. Unless otherwise specified in the plans or contract documents, the thickness shall be 90 mils for edge lines, center lines, lane lines, barrier lines and detail stripe including gore markings, and 120 mils for crosswalks, stop lines, and railroad, word and symbol markings. The measured thickness at the center of the line shall be no less than the specified thickness with the edge of the line not thinner than 75% of the specified center thickness and will be checked at intervals of one mile or less as directed by the Engineer. Any thermoplastic traffic marking less than th e required thickness shall be corrected by overlaying with an additional application of thermoplastic material. Any such required overlay will be no less than 30 mils. Although a tolerance of 25 percent from center to edge is allowed, a consistent underrun of any amount in thickness will not be acceptable. Additional beads by the drop-on method shall be applied at a rate of not less than three pounds of beads per 100 feet of six-inch stripe. When double drop thermoplastic stripe is called for in the contract, additional beads by the drop-on method shall be applied as follows:  Class A glass beads at a rate of not less than three pounds of beads per 100 feet of six-inch stripe. Class B glass beads at a rate of not less than three pounds of beads per 100 feet of six-inch stripe.  The Class B glass beads shall be applied to the newly placed stripe first, followed by the application of the Class A glass beads. All newly applied thermoplastic material shall be protected from traffic until the material is sufficiently dry so as not to sustain damage from vehicle tires. Any material so damaged, marred or picked up by traffic shall be repa ired, and the thermoplastic material tracked onto the pavement shall be removed. The length and width of lines shall be within a tolerance of plus or minus three inches and plus or minus 1/8 inch, respectively. For skip markings, the tolerance for intervals shall not exceed the line length tolerance.

626.04 Method of Measurement. Thermoplastic stripe completed in accordance with

the plans and specifications will be measured by the mile or by the linear foot, as indicated, from end-to-end of individual stripes. In the case of skip lines the measurement will include skips. The length used to measure centerline, lane lines and edge stripes will be the horizontal length computed along the stationed control line. Detail traffic stripe will be measured by the linear foot from end-to-end of individual stripes. Measurements will be made along the surface of each stripe and will exclude skip intervals where skips are specified. Stripes more than six inches in width will be converted to equivalent lengths of six-inch stripe. Legend, which is to include railroad markings, pedestrian crosswalks and stop lines, will be measured by the square foot or linear foot. Pay areas of individual letters and symbols will usually be shown on the plans and measured by the square foot. Transverse railroad bands, pedestrian crosswalks and stop lines will generally be measured by the linear foot, in which case, stripes more than six inches in width will be converted to equivalent lengths of six-inch widths.

626.05 Basis of Payment. Thermoplastic traffic markings will be paid for at the contract

unit price per mile, linear foot, or square foot, as applicable, which shall be full compensation for completing the work. Payment will be made under: 626-A: 6" Thermoplastic * Traffic Stripe, Skip White - per linear foot or mile 626-B: 6" Thermoplastic * Traffic Stripe, Continuous White - per linear foot or mile 626-C: 6" Thermoplastic * Edge Stripe, Continuous White - per linear foot or mile 626-D: 6" Thermoplastic * Traffic Stripe, Skip Yellow - per linear foot or mile 626-E: 6" Thermoplastic * Traffic Stripe, Continuous Yellow - per linear foot or mile