1、Section 13 PAINTING 13.1 GENERAL 13.1.1 Description This work shall consist of the painting of surfaces shown on the plans or otherwise specified to be painted. The work includes, but is not limited to, the preparation of surfaces to be painted, application and curing of the paint, protection of the
2、 work, protection of existing facil- ities, vehicles and the public from damage due to this work, and the furnishing of all labor, equipment, and ma- terials needed to perform the work. the adjacent roadbed and shoulders with water or dust pal- liative for a sufficient distance on each side of the l
3、ocation where painting is being done. Upon completion of all painting operations and of any other work that would cause dust, grease, or other foreign materials to be deposited on the painted surfaces, the painted surfaces shall be thoroughly cleaned. At the time of opening structures to public traf
4、fic, the painting shall be completed, and the surfaces shall be undamaged and clean. 13.1.4 Color 13.1.2 Protection of Public and Property If not otherwise shown or specified, the color of the top or finish coat of paint shall be as directed by the Engineer. The Contractor shall comply with all appl
5、icable envi- ronmental protection and occupational safety and health standards, rules, regulations, and orders. Failure to com- ply with these standards, rules, regulations, and orders will be sufficient cause for suspension or disqualification. All reasonable precautions shall be taken to contain w
6、aste materials (used blasting material and old Paint) classified as hazardous. Disposal of hazardous waste ma- teria1 shall be performed in accordance with all applicable federal, state, and local laws. 13.2.2 Weather Conditions The Contractor shall provide protective devices such as tarps, screens
7、or covers as necessary to prevent damage to the Work and to other Property Or Persons from all cleaning and painting operations. Paint Or Paint Stains that result in an unsightly aP- pearance On Surfaces not designated to be painted shall be removed or obliterated by the Contractor at own ex- pense.
8、 13.1.3 Protection of the Work 13.2 PAINTING METAL STRUCTURES 13.2.1 Coating Systems and Paints The coating system and paints to be applied shall con- sist of the system in Table 13.2.1 which is specified for use or modified by fie special provisions. Paint shall be applied only on thoroughly dry su
9、rfaces. Painting will not be permitted when the atmospheric tem- perature, paint, or the surface to be painted is at or below 40F or above 100“F, or when metal surfaces are less than 5F above the dew point, or when the humidity exceeds 85% at the site of the work, or when freshly painted sur- faces
10、may become damaged by rain, fog, or dust, or when it can be anticipated that the atmospheric temperature will drop below 40F during the drying period, except as pro- vided herein for painting in enclosures. Metal surfaces which are hot enough to cause the paint to blister, to pro- duce a porous pain
11、t film, or to cause the vehicle to sepa- rate from the pigment shall not be painted. Subject to approval of the Engineer, the Contractor may provide a suitable enclosure to permit painting dur- ing inclement weather. Provisions shall be made to artifi- All painted surfaces that are marred or damaged
12、 as a result of operations of the Contractor shall be repaired by the Contractor, at own expense, with materials and to a condition equal to that of the coating specified herein. If traffic causes an objectionable amount of dust, the Contractor, when directed by the Engineer, shall sprinkle 59 1 592
13、 HIGHWAY BRIDGES 13.2.2 TABLE 13.2.1 High Pollution and Mild Climate or Maintenance Coastal Mild Climate Repainting Primer Inorganic Zinc-3 mils. Organic Zinc-3 mils. OilAlkyd-2 mils. Intermediate Coat Epoxy 2 mils or Vinyl Epoxy 2 mils. or Vinyl OilAlkyd-2 mils. Top Coat Epoxy, Vinyl, or Epoxy, Vin
14、yl, or OiYAlkyd-2 mils. Total System 5.3-7 mils. 5.3-7 mils. 6 mils. Wash Primer 0.3-0.5 mils. Wash Primer 0.3-0.5 mils. Urethane-2 mils. Urethane-2 mils. Notes: (1) Except for vinyl wash primer, the coating and system thicknesses shown are minimums. (2) Coating systems shown for severe areas are sa
15、tisfactory in less severe areas. (3) Coastal-within 1,O feet of ocean or tidal water. High Pollution-air pollution environment such as industrial areas. Mild-othex than (4) Inorganic zinc paint shall meet the requirements of Military Specification DOD-P-23236A (SH). (5) Organic zinc paint shall meet
16、 the requirements of Military Specification DOD-F21035A. (6) Vinyl Wash Primer shall meet the requirements of Military Specification DOD-P-15328D. (7) Vinyl top coat paint shall meet the requirements of the Steel Structures Painting Council, SSPC-Paint 9. (8) Epoxy paint shall meet the requirements
17、of the Steel Structures Painting Council, SSPC-22. (9) OiVAUcyd primer and intermediate coat paint shall meet the requirements of the Steel Structures Painting Council, SSPC-Paint 25. coastal area not in air pollution environment. (10) OilAlkyd top coat paint shall meet the requirements of the Steel
18、 Structures Painting Council, SSPC-Paint 104. (1 1) Urethane top coat paint shall meet the recommendations of the Steel Structures Painting Council, SSPC-PS Guide 1700. (12) Paints are hazardous because of their flammability and potential toxicity. Safe handling practices are required and should inc
19、lude, but not be limited to, the provisions of SSPC-PA Guide 3, “A Guide to Safety in Paint Application.” cially control atmospheric conditions inside the enclo- sure within limits suitable for painting throughout the painting operation. Surfaces painted under cover in damp or cold weather shall rem
20、ain under cover until the paint dries or weather conditions permit open exposure. Full compensation for providing and maintaining such en- closures shall be considered as included in the prices paid for the various contract items of work involving painting and no additional compensation will be allo
21、wed therefore. All blast cleaning, except that performed within closed buildings, and all painting shall be performed during day- light hours unless otherwise provided by the contract doc- uments. 13.2.3 Surface Preparation All exposed surfaces of structural steel, except galva- nized or metalized s
22、urfaces, shall be cleaned and painted. All surfaces of new structural steel shall be cleaned by the blast-cleaning method unless otherwise specified in the special provisions, or approved in writing by the En- gineer. In repainting existing steel structures the method of cleaning shall be as specifi
23、ed in the special provisions. Any damage to sound paint, on areas not designated for treatment, resulting from the Contractors operations shall be repaired by the Contractor at own expense to the satis- faction of the Engineer. The methods used in the cleaning of metal surfaces shall conform to the
24、following. 13.2.3.1 Blast Cleaning Abrasives used for blast cleaning shall be either clean dry sand, mineral grit, steel shot, or steel grit, at the option of the Contractor, and shall have a suitable grading to pro- duce satisfactory results. The use of other abrasives will not be permitted unless
25、approved in writing by the Engi- neer. Unwashed beach sand containing salt or excessive amounts of silt will not be allowed. All dirt, mill scale, rust, paint, and other foreign material shall be removed from exposed steel surfaces in accordance with the requirements of the Steel Struc- tures Painti
26、ng Council Surface Preparation Specification No. 10, SSPC-SPlO-Near-White Blast Cleaning. Blast cleaning shall leave all surfaces with a dense and uni- form anchor pattern of not less than 1 nor more than 3 mils. as measured with an approved surface profile com- parator. When blast cleaning is being
27、 performed near machin- ery, all journals, bearings, motors, and moving parts shall be sealed against entry of abrasive dust before blast clean- ing begins. Blast cleaned surfaces shall be primed or treated the same day blast cleaning is done, unless otherwise autho- rized by the Engineer. If cleane
28、d surfaces rust or are con- 13.2.3.1 DIVISION II-CONSTRUCTION 593 taminated with foreign material before painting is accom- plished, they shall be reblast cleaned by the Contractor at own expense. 13.2.3.2 Steam Cleaning All dirt, grease, loose chalky paint, or other foreign material which has accum
29、ulated on the previously painted or galvanized surfaces shall be removed with a steam cleaning apparatus which shall precede all other phases of cleaning. It is not intended that sound paint be removed by this process. Any paint which becomes loose, curled, lifted, or loses its bond with the precedi
30、ng coat or coats after steam cleaning shall be removed as directed by the Engineer to sound paint or metal surface by the Contrac- tor at own expense. A biodegradable detergent shall be added to the feed water of the steam generator or applied to the surface to be cleaned. The detergent shall be of
31、such composition and shall be added or applied in such quantity that the cleaning as described in the above paragraph is accomplished. Any residue, detergent, or other foreign material which may accumulate on cleaned surfaces shall be removed by flushing with fresh water. Steam cleaning shall not be
32、 performed more than 2 weeks prior to painting or other phases of cleaning. Subsequent painting shall not be performed until the cleaned surfaces are thoroughly dry and in no case in less than 24 hours after cleaning and flushing. 13.2.3.3 Solvent Cleaning Unless otherwise prohibited by the special
33、provisions, solvents shall be used to remove oil, grease, and other sol- uble contaminants in accordance with the requirements of SSPC-SP1, Solvent Cleaning. Solvent cleaning shall be performed prior to blast cleaning. If contamination remains after blasting, the area shall be recleaned with solvent
34、. 13.2.3.4 Hand Cleaning Wire brushes, either hand or powered, hand scraping tools, power grinders, or sandpaper shall be used to re- move all dirt, loose rust and mill scale, or paint which is not firmly bonded to the metal surfaces. Pneumatic chipping hammers shall not be used unless authorized in
35、 writing by the Engineer. 13.2.4 Application of Paints The Contractor shall notify the Engineer, in writing, at least 1 week in advance of the date that cleaning and painting operations are to begin. Painting shall be done in a neat and workmanlike man- ner. Unless otherwise specified, paint shall b
36、e applied by brush, spray, or roller, or any combination thereof pecu- liar to the paint being applied. Each application of paint shall be thoroughly cured and any skips, holidays, thin areas, or other deficiencies cor- rected before the succeeding application. The surface of the paint being covered
37、 shall be free from moisture, dust, grease, or any other deleterious materials that would pre- vent the bond of the succeeding applications. In spot painting, old paint which lifts after the first application shall be removed by scraping and the area repainted be- fore the next application. Paints s
38、pecified are formulated ready for application and no thinning will be allowed unless otherwise provided in the applicable materials specification for the paint being used. Brushes, when used, shall have sufficient body and length of bristle to spread the paint in a uniform film. Round, oval-shaped b
39、rushes, or flat brushes not wider than 4% inches shall be used. Paint shall be evenly spread and thoroughly brushed out. On all surfaces that are inaccessible for painting by regular means, the paint shall be applied by sheepskin daubers, bottle brushes, or by any other means approved by the Enginee
40、r. Rollers, when used, shall be of a type that do not leave a stippled texture in the paint film. Rollers shall be used only on flat, even surfaces to produce a paint film of even thickness with no skips, runs, sags, or thin areas. Paint may be applied with airless or conventional spray equipment. S
41、uitable traps or separators acceptable to the Engineer shall be furnished and installed in the airline to each spray pot to exclude oil and water from the air. Any spray method which produces excessive paint build-up, runs, sags, or thin areas in the paint film, or skips and holidays, will be consid
42、ered unsatisfactory and the Engineer may require modification of the spray method or prohibit its use and require brushing instead. Mechanical mixers shall be used to mix paint. Prior to application, paint shall be mixed a sufficient length of time to thoroughly mix the pigment and vehicle together,
43、 and shall be kept thoroughly mixed during its application. The dry film thickness of the paint will be measured in place with a calibrated magnetic film thickness gage ac- cording to Steel Structures Painting Council SSPC-PA2. The thickness of each application shall be limited to that which will re
44、sult in uniform drying throughout the paint film. Succeeding applications of paint shall be of such shade as to contrast with the paint being covered. 594 HIGHWAY BRIDGES 13.2.4 Structures shall be blast cleaned and painted with the total thickness of undercoats before erection. After erec- tion and
45、 before applying subsequent paint, all areas where paint has been damaged or has deteriorated and all ex- posed unpainted surfaces shall be thoroughly cleaned and spot painted with the specified undercoats to the specified thickness. Surfaces exposed to the atmosphere and which would be inaccessible
46、 for painting after erection shall be painted the full number of applications prior to erection. Vinyl wash primer, if required, shall not be applied more than 12 hours before application of the succeeding coat of paint. The vinyl wash primer shall be applied by spraying to produce a uniform wet fil
47、m on the surface. The dry film thickness shall be between 0.3 and 0.5 mils. The painting of areas under joint connection and splice plates shall conform to Article 11.5.6.3. 13.2.4.1 Application of Zinc-Rich Primers Zinc-rich primers, which include organic and inor- ganic zinc primers, shall be appl
48、ied by spray methods. On areas inaccessible to spray application, the paint may be applied by brush or daubers. Mechanical mixers shall be used in mixing the primer. After mixing, zinc-rich primers shall be strained through a metal 30-60 mesh screen or a double layer of cheese- cloth immediately pri
49、or to or during pouring into the spray pot. An agitating spray pot shall be used in all spray appli- cation of zinc-rich primers. The agitator or stirring rod shall reach to within 2 inches of the bottom of the spray pot and shall be in motion at all times during primer ap- plication. Such motion shall be sufficient to keep the primer well mixed. Spray equipment shall provide the proper pot pressure and atomization pressure to produce a coating the com- position of which shall comply in all respects to the spec- ifications for zinc paint. The hose from pot to nozzle shall not
