1、SSPC-TU 2/NACE 6G97February, 997SSPC-TU 2Publication No. 97-04Informational Report and Technology UpdateDesign, Installation, and Maintenance of Coating Systems forConcrete Used in Secondary ContainmentThis NACE International (NACE)/Steel Structures Painting Council (SSPC) report represents a consen
2、sus of thoseindividual members who have reviewed this document, its scope, and provisions. Its acceptance does not in anyrespect preclude anyone, whether he has adopted the report or not, from manufacturing, marketing, purchasing, orusing products, processes, or procedures not in conformance with th
3、is report. Nothing contained in thisNACE/SSPC report is to be construed as granting any right, by implication or otherwise, to manufacture, sell, or usein connection with any method, apparatus, or product covered by Letters Patent, or as indemnifying or protectinganyone against liability for infring
4、ement of Letters Patent. This report should in no way be interpreted as a restrictionon the use of better procedures or materials. Neither is this report intended to apply in all cases relating to thesubject. Unpredictable circumstances may negate the usefulness of this report in specific instances.
5、 NACE andSSPC assume no responsibility for the interpretation or use of this report by other parties.Users of this NACE/SSPC report are responsible for reviewing appropriate health, safety, environmental, andregulatory documents and for determining their applicability in relation to this report prio
6、r to its use. ThisNACE/SSPC report may not necessarily address all potential health and safety problems or environmental hazardsassociated with the use of materials, equipment, and/or operations detailed or referred to within this report. Users ofthis NACE/SSPC report are also responsible for establ
7、ishing appropriate health, safety, and environmentalprotection practices, in consultation with appropriate regulatory authorities if necessary, to achieve compliance withany existing applicable regulatory requirements prior to the use of this report.CAUTIONARY NOTICE: The user is cautioned to obtain
8、 the latest edition of this report. NACE/SSPC reports aresubject to periodic review, and may be revised or withdrawn at any time without prior notice. NACE and SSPCrequire that action be taken to reaffirm, revise, or withdraw this report no later than ten years from the date of initialpublication.Ap
9、proved February 997997, NACE International and SSPCNOTICE TO THE READER: The NACE and SSPC releases of this publication contain identical wording in thesame sequence. Publication format may differ.Steel Structures Painting Council0 2th St.Pittsburgh, PA 222+ (2)2-2NACE InternationalP.O. Box 20Housto
10、n, TX 772-0+ (2)92-0Printed by NACE InternationalNACE 6G197Item No. 24193SSPC-TU 2NACE 6G1972SSPC-TU 2/NACE 6G97February, 997NACE 6G197/SSPC-TU 2666ForewordThis state-of-the-art report covers the design,installation, and maintenance of polymeric coatingsystems that are applied and directly bonded to
11、concrete in secondary containment applications.This report is intended to inform manufacturers,specifiers, applicators, and facility owners who arerequired to contain chemicals and/or protect concretein these applications.Concrete is used in secondary containmentstructures because it is a cost-effec
12、tive material ifproperly designed and installed. A chemical-resis-tant coating is often applied to the concrete to extendthe service life of the secondary containment struc-ture and properly contain the chemicals.Numerous recommended practices, specifica-tions, guides, conference proceedings, books,
13、 andtechnical papers have been published by NACE,SSPC, and other organizations covering the manyaspects of coatings for concrete. This report focuseson those aspects of the design, materials, and pro-cedures that are specific to coatings for concrete insecondary containment applications, making refe
14、r-ence to other publications when appropriate. Whilethere are numerous successful commercial productsand designs for containment of chemicals, this reportfocuses on concrete structures that are coated withthermoset polymer coating systems. Other poten-tially effective containment systems, such as ac
15、id-resistant brick and thermoplastic liners, are notdescribed in this report.Coatings used in secondary containment appli-cations are also called linings, lining systems, orprotective barrier systems; however, for simplicitythey will be referred to as coatings or coatingsystems in this report.This t
16、echnical committee report was drafted byNACE Task Group T-6H-2, a subcommittee of T-6Hon Coating Materials for Atmospheric Service.NACE/SSPC Joint Task Group H* completed thereport, which is published by NACE Internationalunder the auspices of Group Committee T-6 onProtective Coatings and Linings an
17、d by the SteelStructures Painting Council.ContentsSection : Regulations 2Section 2: Service Conditions . Section : Concrete . Concrete Design for New Structures. .2 Existing Concrete Structures . Surface Preparation.Section : Coating System Design Requirements . General .2 Chemical Resistance . Syst
18、em Physical Properties and StressConsiderations. Permeability. Adhesion .6 Thermal Effects .7 Design Details .6. Other Design Factors.2.9 System Compatibility Testing.22Section : Coating Systems2. General .2.2 Polymer Types.2. Reinforcement and Fillers 2. Other Formulation Components. 26. Alternativ
19、e Systems. 26Section 6: Coating System Installation . 276. Concrete Cure and Surface Preparation. 276.2 Patching of Concrete Surface Imperfections 276. Priming . 26. Coating System. 26. Testing and Inspection 0Section 7: Maintenance 7. Spill Cleanup. 7.2 Inspections 7. Repairs . Section : Safety Sec
20、tion 9: Glossary of Terms. 2References Appendix AChemical Conditions 2Appendix BPhysical Conditions Appendix CExamples of Chemicals Within EachType 6Section 1: Regulations. The objective of regulations on secondary con-tainment is to prevent migration of hazardousmaterials into the soil, ground wate
21、r, and surfacewater. In the United States numerous federal, state,and local regulations specifically address thecontainment of hazardous materials.-7The Re-source Conservation and Recovery Act (RCRA)2is aprimary example of the applicable regulations thatrefer to containment of hazardous wastes.2 Reg
22、ulations on secondary containment usuallyrequire that the systems:() prevent migration of hazardous (regulated)materials;(2) have a sound substrate;_*Chairman Fred S. Gelfant, Stonhard Inc., Maple Shade, NJ.SSPC-TU 2/NACE 6G97February, 997NACE 6G197/SSPC-TU 2667() be constructed of or lined with mat
23、erials that arecompatible with the hazardous (regulated)materials;() be free of cracks or gaps; and() contain the capacity of the largest tank.Section 2: Service Conditions2. The exposure of secondary containment sys-tems to various chemicals and physical conditions isusually considered in the selec
24、tion and design of thesystem. This section discusses the classification ofexposure conditions. Appendices A and B listgeneric coating systems that have been successfullyused in each exposure classification.2.2 Chemicals2.2. Classification by TypeMost acids and alkalis attack concrete; coat-ings are
25、used to protect the concrete fromattack. Most solvents and hydrocarbons donot attack concrete; however, they are classi-fied as hazardous materials, and existing regu-lations require that they be contained.Chemicals can be classified by specific typesand concentrations to rate the resistance ofcoati
26、ngs to chemicals. Typically, chemicalswithin a specific class attack polymers in asimilar manner. For acids and alkalis (withsome exceptions), the higher the concen-tration, the more aggressive the attack. Withsolvents, the closer the solvent is to thesolubility parameter of the coating, the morepro
27、ne that coating is to swelling by permeationof that solvent. In addition, the lower themolecular weight of the solvent, the morerapidly it diffuses into the coating.Mixing some chemicals reduces their aggres-siveness to coatings (e.g., mixing acids withalkalis), assuming that the exotherm from themi
28、xing does not cause thermal damage.(Potential thermal damage from exotherm isignored.) Mixing other chemicals significantlyincreases their aggressiveness. For example,mixtures of acids and solvents or mixtures oftwo or more solvents are commonly used aspaint strippers.2.2.2 The chemical types used i
29、n Appendix Ainclude:() inorganic acids(2) organic acids() oxidizers and oxidizing acids() alkalis() chlorinated solvents(6) oxygenated solvents(7) hydrocarbon solvents() salt solutions(9) pesticides and herbicidesExamples of typical chemicals within each typeare given in Appendix C.2.2. Classificati
30、on by Concentration2.2. Most acids and alkalis are fur-ther classified by concentration, usuallypercent by weight in water. When apolymer in a coating is susceptible toattack by a specific chemical, a higherconcentration of that chemical is usuallymore aggressive to the coating (sodiumhydroxide is o
31、ne notable exception).Where a known concentration of a speci-fic chemical is to be contained, com-patibility is determined by testing theresistance of the coating to that con-centration of the chemical.2.2.2 Evaporation, solidification, andmixing can modify the aggressiveness ofa specific chemical.
32、Many acids oralkalis will become more concentrateddue to evaporation if they are spilled at alow concentration on a coating and notcleaned immediately. The higher con-centrations are potentially more aggres-sive toward the coating. Some chemi-cals are spilled in the liquid state butsolidify at ambie
33、nt temperature, thusreducing their mobility and aggres-siveness.2.2. The concentration classifica-tions used in Appendix A vary dependingon the chemical type. For acids andalkalis, Appendix A follows the commonpractice of listing resistance to a diluteconcentration (usually up to 0%, inwater), a med
34、ium concentration (usuallyabove 0%), and a concentrated level(the highest commonly used con-centration). For solvents, Appendix Alists only the resistance to the concen-trated (undiluted) level.2.2. Frequency and Duration of Contact2.2. For coatings that are suitablefor continuous and long-term expo
35、sureto a chemical (i.e., suitable for immer-SSPC-TU 2/NACE 6G97February, 997NACE 6G197/SSPC-TU 2668sion exposure or primary containment),frequency and duration of contact withthe chemical is not a concern; however,for aggressive chemicals that will deg-rade a specific coating system, deter-mining th
36、e frequency and duration ofcontact is important. Many factors canaffect the actual exposure of the coatingto the chemicals that are to be con-tained. These include spill frequency,spill amount, time until dilution or clean-up, effectiveness of dilution or cleanup,and temperature of the spill (see 2.
37、2.).2.2.2 The exposure classificationsused in Appendix A are 72 hours andcontinuous. The 72-hour classificationapplies to secondary containment areassubject to spills that are cleaned as soonas they are detected. The 72-hourchemical resistance requirement is oftenadopted for areas where spills may n
38、otbe detected until after one whole week-end. The 72-hour classification is alsoapplied to areas that are not subject tospills but are designed to contain chemi-cals after catastrophic failure of aprimary containment tank. The contin-uous classification is for areas that aresubject to continuous spi
39、lls or areaswhere spills are not cleaned.2.2. Surface Temperatures2.2. Although spills from processchemicals may initially be at tem-peratures above ambient, these spillsusually cool to ambient conditions in arelatively short period of time. Cata-strophic tank failure for a chemicalstored above ambi
40、ent temperature isone exception. Increases in temperaturecaused by diluting and/or neutralizingconcentrated acids and alkalis couldaffect the maximum temperature towhich the coating is exposed.2.2.2 The surface temperature classi-fications used in Appendix A includeambient temperatures (up to 0C0F),
41、 elevated temperatures (0C to70C 0F to F), and hightemperatures (70C to 00C F to22F). These classifications are im-portant because coatings used in secon-dary containment may deteriorate rapid-ly when exposed to chemicals at ele-vated or high temperatures.2. Physical Conditions2. Ambient Environment
42、2. When classifying the ambientenvironment to determine the exposureand suitability of a coating system,important factors include the tempera-ture range (maximum and minimumsurface temperature), the rate of tem-perature changes (i.e., daily due toambient temperature swings or suddendue to thermal sh
43、ock from chemicalspills), and sunlight exposure.2.2 The ambient temperatureranges used in Appendix B are asfollows: low-temperature range (22C 0C 72F 0F), which includesmost indoor and controlled environ-ments; medium-temperature range(22C 20C 72F 6F), whichincludes most indoor areas withouttemperat
44、ure control and some outdoor,covered areas; wider-temperature range(22C 0C 72F 6F), whichincludes most outdoor environments;and extreme-temperature range (22Cmore than 0C 72F more than 6F), which includes severe hot or coldoutdoor environments.2.2 Traffic ConditionsThe traffic condition classificati
45、ons used inAppendix B include:() occasional foot traffic(2) constant foot traffic() fork lift() drum storage() process area(6) tank storage(7) heavy traffic (tanker trucks, steel-wheeledvehicles)Section 3: Concrete. Concrete Design for New Structures-Proper concrete design and installation practices
46、 arerequired to ensure the performance and success ofthe concrete as the substrate of the secondarycontainment system. Concrete PropertiesSSPC-TU 2/NACE 6G97February, 997NACE 6G197/SSPC-TU 2669Describing specific raw materials and mixdesigns for concrete is beyond the scope ofthis report. These topi
47、cs are adequatelycovered in numerous American ConcreteInstitute documents.()It is important to knowthe desired properties of the finished concretestructure and concrete surface and how theyaffect the coating to be applied. The propertiesof concern, the factors that affect theseproperties, and common
48、 specifications aregiven in the following paragraphs. Strength. Compressive strengthprovides a rigid structural base forthe coating. Tensile strength pro-vides adequate adhesion betweenthe coating system and the con-crete. Tensile and shear strengthensure the concrete survives thestresses applied by the curingcoating on the concrete. Tensileand flexural strength resist crackingin the concrete during curing anddrying of the concrete and duringthermal cycling.2 In addition to instal-lation, finishing, and curing prac-tices, the strength of concrete isaffected
