1、Designation: C946 10Standard Practice forConstruction of Dry-Stacked, Surface-Bonded Walls1This standard is issued under the fixed designation C946; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe
2、r in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers material, workmanship, and con-struction procedures for applying surface bonded mortar toboth sides of dry stacked conc
3、rete masonry units. It does notinclude grout, reinforcing, anchorage, or control joints sincetheir use is essentially the same as conventional concretemasonry construction, unless specifically mentioned in thispractice.NOTE 1Design and construction procedures for conventional concretemasonry constru
4、ction are found in Building Code Requirements forMasonry Structures (TMS 402-08/ACI 530-08/ASCE 5-08) and Specifi-cation for Masonry Structures (TMS 602-08/ACI 530.1-08/ASCE 6-08).1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematica
5、lconversions to SI units that are provided for information onlyand are not considered standard.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 and health pr
6、actices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C55 Specification for Concrete Building BrickC90 Specification for Loadbearing Concrete Masonry UnitsC129 Specification for Nonloadbearing Concrete MasonryUnitsC270 Specificatio
7、n for Mortar for Unit MasonryC887 Specification for Packaged, Dry, Combined Materialsfor Surface Bonding Mortar2.2 Other Documents:TMS 402-08/ACI 530-08/ASCE 5-08 The Masonry Soci-ety, Building Code Requirements for Masonry Structures3TMS 602-08/ACI 530.1-08/ASCE 6-08 The Masonry Soci-ety, Specifica
8、tion for Masonry Structures3TEK 10-2A National Concrete Masonry Association, Con-trol Joints for Concrete Masonry Walls4Standard Practice for Bracing Masonry Walls Under Con-struction, Masonry Contractors Association of America53. Storage3.1 Deliver and store surface bonding mortar in originalcontai
9、ners off the ground to prevent contact with water. Protectfrom rain with suitable covering.3.2 Store concrete masonry units off the ground to preventcontamination by mud, dust, and materials likely to causestaining or other defects, and protect from rain.4. Materials and Manufacture4.1 Concrete maso
10、nry units shall be clean and shall meet therequirements of either Specifications C55, C90,orC129. Thesurface to receive surface bonding mortar shall be free of paint,oil, efflorescence, or foreign materials that interfere withbonding.4.2 Surface bonding mortar shall meet the requirements ofSpecifica
11、tion C887. If the dry mix contains hard lumps, it shallnot be used.4.3 Leveling course shall be bedded with a mortar meetingeither Specification C270 or Specification C887.4.4 Shims shall be corrosion-resistant metal or plastic witha minimum compressive strength of 2000 psi (13.8 MPa), orsteel prote
12、cted from corrosion by a coating of zinc at least 0.8oz/ft2(2.4 gm/mm2), or by a coating of cadmium or zinc ofequivalent corrosion resistance.1This practice is under the jurisdiction ofASTM Committee C12 on Mortars andGrouts for Unit Masonry and is the direct responsibility of Subcommittee C12.06 on
13、Surface Bonding.Current edition approved Jan. 1, 2010. Published February 2010. Originallyapproved in 1981. Last previous edition approved in 2001 as C946 91(2001). DOI:10.1520/C0946-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceas
14、tm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from The Masonry Society, www.masonrysociety.org; AmericanConcrete Institute, www.aci-int.org; and American Society of Civil Engineers,www.asce.org.4Available from
15、the National Concrete Masonry Assn. (NCMA), P.O. Box 781,Herndon, VA 22070, http:/www.ncma.org.5Available from Masonry Contractors Association of America (MCAA), 33South Roselle Rd., Schaumberg, IL 60193, http:/www.masoncontractors.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C70
16、0, West Conshohocken, PA 19428-2959, United States.5. Leveling Courses5.1 Leveling courses, when needed, are to provide a smoothsurface level within14 in. (6.35 mm) in 20 ft (6.1 m), for drystacking concrete masonry units. Leveling courses shall belocated whenever a vertical difference greater than1
17、2 in. (12.7mm) in 10 ft (3.0 m) occurs within one course. Levelingcourses are usually located on the first course above thefoundation, because footings are not normally placed in a levelcondition, and at each floor level.5.2 When Specification C270 mortar or surface bondingmortar is used a leveling
18、course, concrete masonry units shallbe set in a full bed of mortar, laid to a line with the top surfacelevel, as defined in 5.1, and butted together with no mortar inthe head joints. Bed joints shall be struck flush. If the cores areto be grouted, no mortar shall be placed in the space to receivegro
19、ut.5.3 Allow the levelling mortar to set sufficiently so nomovement breaks the bond while dry stacking units in subse-quent courses.6. Dry-Stacking Concrete Masonry Units6.1 Courses of concrete masonry units between the levelingcourses shall be placed without mortar on the bed or headjoints. Place u
20、nits in running bond. Remove burrs and buttblocks tightly.6.2 Use shims, mortar, or surface bonding mortar to plumband level individual units when necessary.6.3 Check the wall every fourth course to be certain it isplumb and level. If any course is out of level by more than12in. (12.7 mm) in 10 ft (
21、3.0 m), another leveling course shall bebuilt.6.4 Cut masonry units to fit openings. Minimum length ofcut piece used in the wall shall be 114 in. (31.8 mm).6.5 Precut units for inserts indicated on drawings.6.6 Anchors, reinforcing, flashing, lintels, and other items tobe built in shall be installed
22、 as the stacking progresses. Cut ornotch masonry units as required.NOTE 2Special consideration must be given to the placement ofbuilt-in items. Surface bonding mortar requires approximately 114 in.(31.8 mm) from the edge of a unit to develop tensile strength across thejoint. Layout of the first cour
23、se with respect to built in items is extremelyimportant, it determines the size of the cut pieces for closure.NOTE 3Utilities such as electrical lines and plumbing located in thecores of the units are best placed prior to the application of surfacebonding mortar while the concrete masonry units are
24、visible.6.7 Cores to be filled with grout shall be aligned to providea continuous, unobstructed opening.6.8 Where a horizontal change in wall thickness occurs, thethicker portion shall end with a solid surface. Use a levelingcourse for the first course in the upper portion.7. Mixing Surface Bonding
25、Mortar7.1 Use clean mixing equipment and water free of deleteri-ous amounts of acid, alkali, and organic materials.7.2 Surface bonding mortar shall be mixed according to themanufacturers instructions and used within the time recom-mended by the manufacturer.7.3 Mix only full bag multiples of materia
26、l to overcome anysegregation of ingredients while in the package.7.4 Mixing time shall be kept to a minimum, as over-mixingmay cause damage to fibers in Specification C887 mortar.7.5 Hand Mixing:7.5.1 Place water in the mixing container.7.5.2 Slowly add the dry surface bonding material.7.5.3 Mix tho
27、roughly.7.6 Machine Mixing:7.6.1 Place water in mixer.7.6.2 Add the surface bonding material to the operatingmixer.7.6.3 Mix thoroughly, 1 to 3 min after all materials havebeen added.7.7 The mixture should be creamy, nonlumpy, and easy toapply.7.8 Admixtures may be permitted within the limits set by
28、Specification C887 and the manufacturer of the surface bond-ing mortar. If desired, admixtures must be specified in thecontract documents.8. Application of Surface Bonding Mortar8.1 Wet the wall uniformly with water immediately beforeapplying surface bonding mortar to prevent excessive suctionof wat
29、er from the surface bonding mortar. If the wall dries priorto application, rewet it. Avoid saturating the units.8.2 Trowel- or spray-apply surface bonding mortar to bothsides of the dry-stacked concrete masonry units.8.3 Completely cover the wall surface with a minimumthickness of18 in. (3.2 mm) of
30、surface bonding mortar bytrowel or spray.8.4 When a second coat of surface bonding mortar is to beapplied, the first coat shall have taken its initial set but not becompletely hardened or dried out. If the first coat has com-pletely hardened or dried out, consult the manufacturersrecommendations for
31、 application of a second coat, since abonding agent may be required.8.5 Finish to the texture specified.8.6 If application of surface bonding mortar is discontinuedfor more than 1 h, the horizontal joint between the twoapplications, other than at wall tops, must occur at least 114 in.(31.8 mm) from
32、the horizontal edge of the concrete masonryunit.9. Curing and Protection9.1 At ambient temperatures below 40F (4.4C) or above90F (32.2C), follow the Specification for Masonry Structures(TMS 602-08/ACI 530.1-08/ASCE 6-08).9.2 Dampen the wall with a water mist after 8 h, but within24 h of application
33、of the surface bonding mortar.9.3 Fog spray twice within the first 24 h from application ofthe surface bonding mortar. With pigmented mortar, the timemay be extended to 48 h. With maximum temperature in excessof 90F (32.2C), wind speed greater than 20 mph (32.2 km/h),or mean relative humidity less t
34、han 50 % relative humidity,more frequent application of fog spray shall be necessary.9.4 The top of the walls shall be covered with a nonstaining,waterproof covering, extending at least 2 ft (0.6 m) on eachside of the wall to prevent moisture from entering the wall untilthe top is permanently protec
35、ted.C946 10210. Other Requirements10.1 Requirements concerning grout, reinforcement, an-chors, ties, corrosion resistance, dimensional tolerances, wallbracing after coating, and miscellaneous items unless specifiedby the manufacturer of the surface bonding mortar shall beoutlined in the following:10
36、.1.1 TMS 402-08/ACI 530-08/ASCE 5-08, BuildingCode Requirements for Masonry Structures.10.1.2 TMS 602-08/ACI 530.1-08/ASCE 6-08, Specifica-tion for Masonry Structures.10.1.3 Standard Practice for Bracing Masonry Walls UnderConstruction.10.2 Control Joints:10.2.1 Location, spacing, and type of contro
37、l joints shallmeet the requirements of TEK 10-2A, Control Joints forConcrete Masonry Walls.10.2.2 Control joints shall be uniform in width, through thewall, and continuous from top to bottom of the wall.10.2.3 Remove surface bonding mortar from the controljoint.11. Keywords11.1 dry stacked; fiber re
38、inforced; mortar; packaged; surfacebondingASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and t
39、he riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision
40、of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shoul
41、dmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, 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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).C946 103
