1、Designation: C 1400 01 (Reapproved 2007)Standard Guide forReduction of Efflorescence Potential in New Masonry Walls1This standard is issued under the fixed designation C 1400; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the yea
2、r of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers methods for reducing efflorescencepotential in new masonry walls.1.2 The values stated in inch
3、-pound units are to be regardedas the standard. The SI units given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety an
4、d health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C43 Terminology of Structural Clay ProductsC67 Test Methods for Sampling and Testing Brick andStructural Clay TileC 270 Specification for Mortar for Unit MasonryC 118
5、0 Terminology of Mortar and Grout for Unit MasonryC 1209 Terminology of Concrete Masonry Units and Re-lated UnitsC 1232 Terminology of Masonry3. Terminology3.1 Definitions:3.1.1 Terminology defined in Terminologies C43, C 1180,C 1209, and C 1232 shall apply in this guide.3.2 Definitions of Terms Spe
6、cific to This Standard:3.2.1 cryptoflorescence, na crystalline deposit of water-soluble compounds in the pores of masonry3.2.2 efflorescence, na crystalline deposit, usually white,of water-soluble compounds on the surface of masonry.3.2.2.1 DiscussionThe color of stains produced by acid-soluble vana
7、dium compounds in clay masonry is usuallyyellow or green. The color of stains produced by acid-solublemanganese compounds is usually brown or gray.4. Significance and Use4.1 This guide provides information that, if implemented,will reduce efflorescence potential in new masonry walls.However, its imp
8、lementation will not always completely pre-vent efflorescence.4.2 This guide may be augmented by related informationcontained in the appendixes of Specification C 270, the addi-tional material listed at the end of this specification, and otherpublications.5. Principles of Efflorescence5.1 Effloresce
9、nce is directly related to the quantity ofwater-soluble compounds within, or exposed to, the wall; andto the quantity of water exposed to these compounds. Sinceneither water nor water-soluble compounds can be completelyeliminated from an exterior masonry wall, the potential forefflorescence is reduc
10、ed by reducing water-soluble compoundsand water within the wall.5.2 While water penetration is reduced through properdesign and construction, water can penetrate into masonrywalls through cracks and separations in the surface and the topof the wall. It can penetrate voids in the mortar joints or the
11、interface between the unit and mortar, and, to a lesser degreethrough the masonry units and the hardened mortar.5.3 If a significant amount of water penetrates the wall, thewater will dissolve water-soluble compounds that may exist inthe masonry units, mortar components, grout, admixtures orother se
12、condary sources, and may deposit them on the exteriorsurface of the masonry when it migrates to the wall surfacethrough evaporation. Deposits may also form within themasonry resulting in cryptoflorescence.5.4 The most common efflorescence deposits contain two ormore of the following: potassium, sodi
13、um, calcium, sulfates,carbonates, bicarbonates, chlorides, and hydroxides.5.5 Some water-soluble compounds deposited on the sur-face of masonry can chemically react to form compounds thatare not water-soluble. Calcium carbonate (CaCO3) deposits on1This guide is under the jurisdiction of ASTM Committ
14、ee C15 on ManufacturedMasonry Units and is the direct responsibility of Subcommittee C15.05 on MasonryAssemblies.Current edition approved Dec. 1, 2007. Published January 2008. Originallyapproved in 1998. Last previous edition approved in 2001 as C 1400 01.2For referenced ASTM standards, visit the AS
15、TM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, Unit
16、ed States.masonry are a fairly common example. They are a result ofreaction between the efflorescence compound calcium hydrox-ide and carbon dioxide after the calcium hydroxide is depositedon the surface of the masonry and is exposed to the air.5.6 Under some circumstances, particularly when exterio
17、rcoatings are present, efflorescence compounds can be depos-ited below the surface of the masonry units. This condition iscalled cryptoflorescence. When cryptoflorescence occurs, theforces resulting from its confinement can cause disintegrationof the masonry surfaces.6. Reduction of Efflorescence Po
18、tential in New MasonryWalls6.1 Efflorescence on a new masonry wall is reduced whenwater penetration of the wall is minimized; when water thatpenetrates or condenses in the wall is quickly drained from thewall; when contact between dissimilar masonry units isavoided; and when potential efflorescence
19、compounds in thewall materials are minimized.6.2 The amount of water from wind-driven rain that is ableto penetrate a masonry wall is minimized by:6.2.1 Good bond and full contact between masonry unitsand mortar. This condition is achieved by using mortar that iscompatible with the masonry units; co
20、mpletely filled head andbed mortar joints in solid unit masonry; completely filled faceshells head and bed joints in hollow unit masonry; compactedconcave, V, or grapevine mortar joints on the exterior face ofthe wall; cold weather construction practices that preventmasonry materials from freezing;
21、and by hot weather construc-tion practices that prevent newly placed mortar from dryingrapidly.6.2.2 Construction practices that protect the tops and sidesof uncompleted walls and openings from rain or snow duringconstruction.6.2.3 The use of flashing at the intersection of roofing andmasonry walls.
22、6.2.4 The use of sills, copings, and chimney caps of solidmasonry units, stone, reinforced concrete, or corrosion resis-tant metal. To be most effective, masonry, stone, and concretesills, copings, and chimney caps should project beyond the faceof the wall; have drips that are at least 1 in. (25 mm)
23、 from theface of the wall, and have functional flashing and weep holes.In addition, all sills, copings, and chimney caps should besloped a minimum of 1+4; be mechanically anchored to thewall, and should have properly sized, located, and sealedmovement joints when necessary.6.2.5 Properly sized, loca
24、ted, and sealed movement joints inwall and around openings in wall.6.2.6 Overhangs to protect the wall from rain.6.2.7 Utilization of compatible water repellent coating onconcrete masonry walls or integral water repellent admixturesin concrete masonry units.6.3 Water that penetrates a masonry wall i
25、s quickly drainedout of the wall by:6.3.1 Unobstructed drainage in air space of drainage walls.6.3.2 Functional, unpunctured flashing and weep holes atbase of wall above grade; above openings in wall, shelf angles,lintels, wall-roofing intersections, chimneys, and bay windows,and below window sills
26、and copings. The flashing should beextended beyond the exterior face of the wall. The flashingshould have end dams at its discontinuous ends, and properlysealed splices and laps at its joints.6.4 Contact between dissimilar masonry units is avoided by:6.4.1 The use of cavity walls with unobstructed 2
27、 in. (50mm) minimum drainage air space to separate the exteriormasonry wythe from the backup wall consisting of a dissimilarmasonry unit.6.4.2 The use of flashing between masonry wall and sills,copings, and chimney caps of a dissimilar material.6.4.3 The use of flashing or separator between changes
28、inmaterials in wall.6.5 Potential efflorescence compounds in the wall materialscan be minimized by:6.5.1 Preconstruction testing of all masonry materials, wa-ter, cleaning agents, and admixtures to be used in a masonrywall to evaluate their potential to contribute to efflorescence.The results of the
29、se tests should be evaluated together with theinfluence of construction practices and design in predictingefflorescence potential in masonry walls. Available precon-struction tests include: Test Methods C67efflorescence test forbrick; chemical analysis of cements to determine water solublealkali (Na
30、2OK2O) content; chemical analysis of hydrated limeto determine calcium sulfate content; and chemical analysis ofsand, water, admixtures and cleaning agents to determinealkali, chloride, and sulfate content. Presently, there is noASTM efflorescence test for concrete masonry units or mortar.The potent
31、ial for efflorescence increases with increasingamounts of water-soluble alkali, chlorides, and sulfates in themasonry wall materials.6.5.2 Storage and protection of all masonry materials priorto use to prevent contact with dissimilar materials and toprotect materials from moisture.6.5.3 Protection o
32、f all masonry materials during transporta-tion when there is a probability of contamination from roadsalts, fertilizers, and airborne contaminants.6.5.4 Utilization of proper cleaning materials and proce-dures on new masonry walls.7. Keywords7.1 efflorescence; end dam; flashing; masonry units; morta
33、r;preconstruction testing; water penetration; weep holesC 1400 01 (2007)2ADDITIONAL MATERIAL(1) Brownell, W. E., “The Causes and Control of Efflorescence onBrickwork,” Research Report Number 15, Structural Clay ProductsInstitute, McLean, VA, August 1969.(2) Chin, I. R., and Petry, L., “Design and Te
34、sting to Reduce Efflores-cence Potential in New Brick Masonry Walls,” Masonry: Designand Construction, Problems and Repair, ASTM STP 1180,J.M.Melander and L. R. Lauersdorf, Eds., American Society for Testingand Materials, Philadelphia, 1993, pp. 317.(3) “Control and Removal of Efflorescence,” NCMA-T
35、EK 8-3A, Na-tional Concrete Masonry Association, Herndon, VA, 1996.(4) “Efflorescence Causes and Mechanisms, Part I of II,” TechnicalNotes 23 (revised), Brick Institute of America, Reston, VA, May1985.(5) “Efflorescence Prevention and Control, Part II of II,” TechnicalNotes 23A (revised), Brick Inst
36、itute of America, Reston, VA, June1985.(6) Grimm, C. T. “Water Permeance of Masonry Walls: A Review ofthe Literature,” Masonry: Materials, Properties, and Performance,ASTM STP 778, J. G. Borchelt, Ed., American Society for Testingand Materials, Philadelphia, PA, 1982, pp. 178199.(7) Grimm, C. T., Th
37、e Hidden Flashing Fiasco, Construction ResearchCenter, University of Texas at Arlington, April 1994.(8) “Trowel Tips: Efflorescence,” 1S239, Portland CementAssociation,Skokie, IL, 1991.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any i
38、tem mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical co
39、mmittee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a
40、 meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Dri
41、ve, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C 1400 01 (2007)3
