SPECIAL SPECIFICATION 5478 Anti-Graffiti Coating

Transcription

1 1995 Metric CSJ SPECIAL SPECIFICATION 5478 Anti-Graffiti Coating 1. Description. This Item shall govern for furnishing, surface preparation and application of materials used to deter the adhesion of graffiti onto porous surfaces. 2. Materials. This specification shall govern for the materials, quality, sampling, testing and pre-qualification of 2 types, Type I - Sacrificial and Type II - Permanent, of anti-graffiti coating. (1) Bidder's and/or Supplier's Requirements. All bidders and/or suppliers are notified that before any bid is considered, the materials proposed for submission shall be of manufacturer and product code or designation shown on the list of approved manufacturers of materials covered by this Item and maintained by the Materials Section Construction Division (CSTM). (2) Establishment of Quality. (a) Pre-qualification as an Approved Source. Prospective suppliers, who desire to establish pre-qualification for materials governed by this specification, shall submit a 1 liter sample of the material to be pre-qualified to the Director of CSTM, Texas Department of Transportation (TxDOT), Construction Division, Director of Materials and Pavements, 9500 Lake Creek Parkway, Austin, Texas The Department will evaluate, at no cost to the supplier, one formulation per supplier for conformance with the requirements of this specification. A Material Safety Data Sheet that complies with OSHA's Hazard Communication Standard 29 CFR shall accompany the sample. If approved for use by TxDOT, the material(s) will be appended to the list of approved products maintained by CSTM. Any additional samples necessary to establish quality shall be charged to the supplier at a rate of $ per sample. Additional samples, after the first, necessary to establish quality, shall be accompanied by a written request for evaluation and a Cashier's Check in the amount of $ made out to the Highway Fund. (b) Formulation Changes. One submission of a reformulation of an approved product will be permitted per year at no cost to the supplier. Any change in formulation detected without re-qualifying will be cause to withdraw qualification. A supplier who has had an approved product withdrawn due to formulation changes shall bear all costs of re-qualifying at the rate of $ per sample. Furthermore, re-qualifying will not be allowed in less than 6 months

2 (3) Sampling and Testing. All anti-graffiti coatings shall be sampled and tested. Sampling and testing will be in accordance with TxDOT's Manual of Testing Procedures. Costs of sampling and testing are normally borne by TxDOT; however, the costs of sampling and testing of materials failing to conform with the requirements of this specification will be borne by the Contractor or supplier. Costs of sampling and testing of failing materials will be assessed at the rate established by the Director of CSTM in effect at the time of testing. Amounts due the Department for conducting such tests will be deducted from partial or final payments on direct purchases by the State. The Contractor or supplier may be required to reimburse TxDOT for the costs of storage and/or handling of material failing to meet specification requirements. (4) Material Requirements. The Contractor shall secure materials in sufficient time to allow for testing and timely execution of the work. All anti-graffiti coatings shall meet the specific requirements for each type of coating. Requirements set forth for antigraffiti coatings, which are proprietary in nature, do not relieve the manufacturer and/or the Contractor of any obligations relating to patents, nor does it give the manufacturer the right to patent infringement. Anti-graffiti coatings may be used for above grade concrete, concrete block, exposed aggregate concrete, brick and stonework. The anti-graffiti coating shall not react deleteriously with any of the above substrates. When applied it shall produce a firm, continuous, uniform film which is free of pinholes, cracks, or other film defects and exhibit satisfactory adherence. The consistency shall be such that the coating can be satisfactorily applied by spray, by roller, or by brush at atmospheric and material temperatures above 10 C without thinning. When applied properly to vertical surfaces, the material shall not sag, disintegrate, check, peel, crack, or otherwise not form a uniform coating during the required curing period. Primers, when recommended by the manufacturer, shall be the same formulation and type as that pre-qualified by CSTM. (a) Type I Sacrificial. (i) General. Type I coating systems are sacrificial coatings that require a pressurized water wash for graffiti removal. Pressure wash requirements shall not exceed 10,350 kpa and 60 C. The coating shall protect the substrate from damage during the pressure wash. Type I coatings shall be clear or translucent. (ii) Specific. When tested in accordance with Test Method Tex-890-B, the Type I coating shall exhibit resistance to graffiti staining. The density shall not vary by more than ± kilograms per liter from the density established on the preliminary evaluation sample. The infrared spectra of the coating shall match that of the preliminary evaluation sample. The percent solids shall be within 2% of that established on the preliminary evaluation sample. A 75 micrometer wet film shall be set-to-touch in not more than 1 hour and shall be dry through in not more than 4 hours. The coating shall be free of skins, agglomerates, or

3 other undesirable particles as determined by the last paragraph of the procedure in Test Method Tex-805-B. (b) Type II Permanent. (i) General. Type II coatings are two-component, permanent coatings that do not require a re-coat after graffiti removal. Graffiti removal is a two- step process. The first step is to brush a graffiti remover or solvent onto the graffiti. The second step is to remove the graffiti using either rags or a water-wash. A waterwash can only be used if a biodegradable and water soluble graffiti remover is used. The graffiti remover or solvent shall be approved for use by the Engineer. The Type II coating shall not suffer any damage or pigment loss due to the use of a graffiti remover and/or solvent. When properly applied, the coating shall withstand a methyl ethyl ketone rub test when tested in accordance with ASTM D Unless otherwise shown on the plans, the color of Type II anti-graffiti coatings shall be concrete gray. When other colors are shown on the plans, the color of the Type II coating shall match the color standard supplied by the Engineer. (ii) Specific. The densities for the base and cure components of the anti-graffiti coating shall not vary more than plus or minus 0.1 pound per gallon from the densities established on the preliminary evaluation samples. The infrared spectra of the base and cure components shall match those of the preliminary evaluation samples. The percent solids of the base and cure components shall be within 2% of that established on the preliminary evaluation samples. When tested in accordance with Test Method Tex-890- B, the cured coating shall exhibit resistance to graffiti staining. The cured coating shall have a minimum sag resistance of 4 mil. A 3 mil wet film of the coating shall be setto-touch in not more than 4 hours and shall be dry through in not more than 24 hours. 3. Container and Markings. Shipment will be made in suitable, strong, well-sealed containers which meet Federal requirements and are sufficiently sturdy to withstand normal shipping and handling. Finished product containers and cases will be plainly and securely labeled with: (1) Manufacturer's name (2) Product designation, including component part (3) Batch number (4) Date of manufacturer, and (5) Net volume. Labeling will be on the sides of containers and cases and shall be sufficiently moisture resistant to withstand outdoor storage for a minimum of 1 year. Containers shall be protected from freezing. When the finished product is palletized for shipment, the labels will be to the outside for easy identification

4 4. Construction Methods. In preparation for the application of anti- graffiti coatings, all surfaces shall be cleaned to remove laitance, curing compound, dirt, grime and other contaminants. Concrete surfaces shall be blast cleaned; the blast cleaning shall be in accordance with Item 427, Surface Finishes for Concrete, Subarticle (1). For other surfaces the cleaning method used shall be approved by the Engineer. A primer, when required by the manufacturer, shall be applied in accordance with the manufacturer's recommendations. If the anti-graffiti coating is to be applied over an existing concrete coating, the concrete coating shall first be cleaned of dirt, grime and other contaminants to meet the tape test described in Subarticle (1) of Item 427. The cleaning method used shall be approved by the Engineer, before the application of the anti-graffiti coating. Material preparation and equipment requirements shall be in accordance with the manufacturer's recommendations. The anti-graffiti coating shall not be thinned for application without the approval of the Engineer. The anti-graffiti coating shall be applied after the cleaning has been completed and just prior to the final acceptance of the work unless otherwise approved by the Engineer. Anti-graffiti coatings require a dry surface. The temperature of the atmosphere, substrate surface and material shall be above 10 C at the time of application. Anti-graffiti coatings shall not be applied when impending weather conditions might result in injury to the fresh coating. Anti-graffiti coatings may be applied by spraying, by roller, or by brush. When application is by spray, the applicator shall spray in deliberate length passes, triggering the spray gun at the end of each pass, overlapping adjacent passes 20 to 40%. The spray gun shall be aimed so that the material is meeting the surface at an angle not less than 80 degrees. Applicators who do not practice the above techniques will not be allowed to paint on this project. Type I coatings shall be applied in a minimum of 2 coats. A minimum of 1 hour dry time shall be allowed between coats. Total coverage shall be at the rate of not more than: Smooth finish concrete, 2.5 square meters per liter; and exposed aggregate concrete, brick, stonework, and striated concrete, 1.9 square meters per liter. Type II coatings shall be applied at a total coverage rate of not more then 6 square meters per liter. A minimum 4 hour dry time shall be allowed between coats. Note: It is imperative that the anti-graffiti coating product name, producer name, and the exact location where the coating was applied be recorded for future reference. Type I coatings require a recoat after graffiti removal; it is important that the material applied for the recoat be the same as the material that was initially applied. Product performance may be compromised by combining different products. Subsequent recoats of Type I material do not require the surface preparation as specified under Article 4; however, re-application shall not proceed until the surface has dried to a damp dry (usually within 1 hour, depending on weather conditions). The recoat shall be applied at a total coverage rate of not more than 3.7 square meters per liter

5 5. Measurement. Anti-graffiti coatings will be measured by the square meter of surface coated. This is a plans quantity measurement Item and the quantity to be paid for will be that quantity shown in the proposal and on the Estimate and Quantity sheet of the contract plans, except as may be modified by Article 9.8. If no adjustment of quantities is required, additional measurements or calculations will not be required. 6. Payment. The work performed and materials furnished in accordance with this Item and measured as provided under Measurement will be paid for at the unit price bid for Antigraffiti Coating - Type I, and/or Anti-graffiti Coating-Type II. These prices shall be full compensation for furnishing all materials, for cleaning existing surfaces, for application of material and for all labor, tools, equipment and incidentals necessary to complete the work