WORK ZONE TRAFFIC PATTERN MASKING:

(10/21/2018)

Description

Furnish and install Work Zone Traffic Pattern Masking material for placement on existing asphalt or concrete pavements during work zone operations.The Work Zone Traffic Pattern Masking material shall be black in color and used during traffic pattern changes to completely cover the entire pavement surface; thus masking/concealingthe existing pavement markings and allowing the revised work zone pavement markings to be placed on a newly applied black surface. Its purpose is to eliminate the grind marks and “ghost markings” on pavement surfaces which can create motorist confusion and pavement damage while providing an incomparable contrast between therevitalized black pavement color and newly applied pavement markings for work zone patterns of up to a year.

Materials

A)General

Use materials in accordance with Manufacturer’s recommendations that will retain a black color for a period of up to 12 months. The black material shall bea flat black color when fully cured and shall completely mask/conceal the existing pavement markings for the same 12 month period.

The material shall not exhibit glare orretroreflectance in either day or night conditions. To ensure the material provides ample concealment and doesn’t exhibit excessive glare, the materialopaqueness shall be a minimum of 95% and the retroreflective properties shall not exceed4 mcd/lux/m2.

It shall not adversely affect the ability of the pavement to drain water or make the pavement adversely slick in either dry and wet conditions and shall meet the skid properties as described in Section C below.

The material shall not contain any petroleum components and shall not contain any Volatile Organic Compounds (VOC’s).

The material shall not exhibit excessive cracking or create excessive cracking to the pavement surface after placement.

In addition, it shall be manufactured to bond successfully to both concrete and asphalt pavements and allow resurfacing treatments to be applied directly over its surface without having to be removed for successful bonding of the new asphalt or concrete overlays.

It should also be manufactured to receive any type ofpolyurea,epoxy, polymer, cold applied plastic,or thermoplastic pavement marking materials.

B) Material Qualifications/Certifications

Use Work ZoneTraffic Pattern Masking materials that are on the NCDOT Approved Products List. Provide a Type 3 (Manufacturers) Certification in accordance with Article 106-3 in the North Carolina Standard Specifications for Roads and Structures to ensure the material meets or exceeds the requirements in this specification.

In addition, provide a Type 5 (Typical Certified Test Report) Certification in accordance with Article 106-3 in the North Carolina Standard Specifications for Roads and Structures that ensures the material has been tested by an independent testing company that meets or exceeds the braking/skid requirements as described in Section (C) below.

C) Performance

The Work Zone Pattern Masking material shall be tested by an independent test laboratory for skid properties according to the test standards in ASTM E274 or ASTM E303-93 (2008). The material shall provide minimum frictional resistance numbers when tested with either test standard. The minimum average Skid Number (SN) for ASTM E274 is 37. The minimum average British Pendulum Number (BPN) for ASTM E303-93 (2008) is 37.

The work zone travel lane shall retain its black distinguishable appearance throughout the life of the traffic pattern. Normal wearing is expected in the wheel paths of the travel lanes, but the work zone travel lanes shall always have a noticeable black appearance at all times during the expected 12-month traffic pattern life.

At any time this material fails to keep previously installed pavement markings concealed, resulting in conflicting traffic patterns or does not retain its black color contrast for the required 12-month duration, it is not meeting the requirements and intention of this specification and shall be replaced immediately.

The Work Zone Pattern Masking material shall retain its black color and continue to conceal the pavement markings underneath after a single snowplow event within its 12-month expected life.

If the work zone experiences more than 1 snowplowing event, the Engineer will determine if the Work Zone Pattern Masking is still performing adequately or if replacement is necessary due to excessive damage caused by snowplow activities. If the material is damaged to the point where 20% or more of the concealed pavement markings are revealed, it shall be replaced, at an 8” width to re-conceal the exposed pavement markings, at the contract unit price unless the traffic pattern is to change within 30 days.

Poor performance of Work Zone Pattern Masking material at any site, whether or not related to a specific contract may be grounds for removing the material from the NCDOT Approved Products List and or removing from any project under contract.

Construction Methods

A) Application Equipment

The equipment to apply Work Zone TrafficPattern Masking material shall be truck mounted pneumatic or airless spray machines with suitable arrangement of atomizing nozzles and controls to cover the entire pavementsurface to achieve uniform coverage with consistent thickness as required in thisspecification. Do not use hand applied methods or any other non-truck mounted application equipment or device to install material for applications longer than 1,000 feet.

The application spray equipment shall be set up in such a manner to apply the Work Zone TrafficPattern Maskingmaterial inspray pattern widths to ensure complete and uniform coverage of the entire travelway and to reduce the overlap from multiple passes. If the application equipment isn’t equipped to spray a full 12’ travel lane in a single pass, it shall be set-up to spray a 6 foot minimum width. No more than 2 passes per travel lane will be allowed. A 1” overlap width is required when applying the material in less than the full width of the travel lane.

B) Material Application

TheWork ZoneTraffic Pattern Masking material is to be applied to the full width and length of the pavementsurface where traffic patterns are to change thus masking/concealing the existing pavement markings as well as providing a new black surface for the placement of the revised pavement markings. The masking/concealmentof individual pavement marking edge lines, skips, mini skips, lane lines or gore lines is not allowed.

The Work Zone Traffic Pattern Masking material shall be applied at a uniform thickness of approximately 16 mils(+/-) directly onto the existing pavement. Thematerial shall be set and/or cured to receive pavement markings within 10 minutes of installation according to the temperature requirements stated within this specification.

C) Surface Preparation

i)Asphalt- The existing pavement surface shall be swept clean and prepared in accordance with the Manufacturer’s recommendations to receive the Work Zone Traffic Pattern Maskingmaterial. Although, no existing pavement marking line removal is required, any loose, flaking or other laitance material from existing markings shall be machine broomed or scarifed as directed by Manufacturer before placing the Work Zone Traffic Pattern Masking material.

ii) Concrete- The existing concrete surface shall be swept clean and prepared in accordance with the Manufacturer’s recommendations to receive the Work Zone Traffic Pattern Masking material.

Although, no existing pavement marking line removal is required, any loose, flaking or other laitance material from existing markings shall be machine broomed or scarifed as directed by Manufacturer before placing the Work Zone Traffic Pattern Masking material.

NOTE: For newly placed concrete pavements, newly installed concrete bridge decks or existing concrete pavements that do not receive a surface treatment, Work Zone Traffic Pattern Masking Material shall not be placed. The conflicting pavement marking lines shall be removed by water blasting methods only.

D) Temperature and Weather Limitations

Do not apply Work Zone Traffic Pattern Masking material unless the ambient air temperature and the pavement temperature is 40F or higher. Do not install unless the pavement surface is completely dry and not within 4 hours of a significant rain event such as a thunderstorm with rainfall intensities greater than 1 inch/per hour. Always follow the Manufacturer’s recommendations for placement during periods of excessive humidity.

Maintenance

There should be no required maintenance of the Work Zone Traffic Pattern Masking material. Replace any Work Zone Traffic Pattern Masking material that prematurely fails to keep pavement markings masked/concealed for the full 12 month duration. Any traffic control or material costs due to replacement will be at no cost to the Department.

Measurement and Payment

Work Zone Traffic Pattern Masking material will be measured and paid by the square foot. The quantity of material that’s to be paid is calculated by multiplying the length by the width of all lanes affected by each work zone traffic pattern change.

Pay ItemPay Unit

Work Zone Traffic Pattern MaskingSquare Foot