1、Designation: C 635/C 635M 07Standard Specification forthe Manufacture, Performance, and Testing of MetalSuspension Systems for Acoustical Tile and Lay-in PanelCeilings1This standard is issued under the fixed designation C 635/C 635M; the number immediately following the designation indicates the yea
2、rof original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Departm
3、ent of Defense.1. Scope1.1 This specification covers metal ceiling suspension sys-tems used primarily to support acoustical tile or acousticallay-in panels.1.2 Some suspension systems incorporate locking assemblydetails that enhance performance by providing some continuityor load transfer capability
4、 between adjacent sections of theceiling grid. The test methods included in this specification donot provide the means for making a complete evaluation ofcontinuous beam systems, nor for assessing the continuitycontribution to overall system performance. However, the testmethods can be used for eval
5、uating primary structural mem-bers in conjunction with secondary members that interlock, aswell as with those of noninterlocking type.1.3 While this specification is applicable to the exteriorinstallation of metal suspension systems, the atmosphericconditions and wind loading require additional desi
6、gn attentionto ensure safe implementation. For that reason, a specificreview and approval should be solicited from the responsiblearchitect and engineer, or both, for any exterior application ofmetal suspension systems in the construction of a new buildingor building modification.1.4 The values stat
7、ed in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.5 Th
8、e following safety hazards caveat pertains only to thetest methods described in this specification. This standard doesnot purport to address all of the safety concerns, if any,associated with its use. It is the responsibility of the user of thisstandard to establish appropriate safety and health pra
9、cticesand determine the applicability of regulatory limitations priorto use.2. Referenced Documents2.1 ASTM Standards:2B117 Practice for Operating Salt Spray (Fog) Apparatus3. Terminology3.1 Definitions:3.1.1 Where these terms appear in this specification theyshall have the meaning herein indicated
10、as follows:3.1.1.1 backing board a flat sheet of gypsum board towhich acoustical tile is attached using adhesive, screws,staples, or other suitable means (Fig. 1c).3.1.1.2 bowthe maximum component of deviation in thevertical plane of a main runner, cross runner, or wall moldingwhere the centroidal a
11、xis of these structural components hasbeen permanently deformed from end to end into the shape ofa simple regular curve during the manufacturing process (Fig.2).NOTE 1The meanings for bow and camber given here may differ fromthose applied elsewhere.3.1.1.3 camberthe maximum component of deviation in
12、the horizontal plane of a main runner, cross runner, or wallmolding where the centroidal axis of these structural compo-nents has been permanently deformed from end to end into theshape of a simple regular curve during the manufacturingprocess (Fig. 2).3.1.1.4 carrying channel or hanging channelthe
13、three-sided or “”-shaped metal sections that support the entirestructural grid network in some forms of mechanical ceilingsuspension systems (Fig. 1b). The carrying channels areusually suspended by hanger wires from the existing structureand the main runners are then attached to the channels.3.1.1.5
14、 ceiling suspension systemthe entire network orgrid of structural components, as defined by the ceilingsuspension system manufacturer, that provides support for1This specification is under the jurisdiction of ASTM Committee E33 onBuilding and Environmental Acoustics and is the direct responsibility
15、of Subcom-mittee E33.04 on Application of Acoustical Materials and Systems.Current edition approved Oct. 1, 2007. Published October 2007. Originallyapproved in 1969. Last previous edition approved in 2004 as C 635 04.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AST
16、M 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, United States.acoustical ceiling tile, acou
17、stical ceiling panels, lighting fix-tures, and air diffusers.3.1.1.6 cross runner the secondary or cross beams of amechanical ceiling suspension system (Fig. 1, a and b). Thecross runners usually support only the acoustical tile. In someforms of suspension systems, however, the cross runners alsopro
18、vide support for lighting fixtures, air diffusers, and othercross runners.3.1.1.7 hanger wire the wire employed to suspend theacoustical ceiling from the existing structure (wood joists, steelbar joists, steel beams, concrete slabs, etc.) (Fig. 1).3.1.1.8 horizontal plane (of a structural component
19、of aceiling suspension system)a plane parallel to the plane of theceiling which passes through the centroidal axis of the member(Fig. 2).3.1.1.9 interlockinga ceiling system where the cross run-ners are connected to the main runner or other cross runners, orboth, at intervals controlled by slots, ho
20、les, etc. in the mainrunners.3.1.1.10 main runner the primary or main beams of thetype of ceiling suspension system in which the structuralmembers are mechanically locked together (Fig. 1, a and b).FIG. 1 Three Types of Ceiling Suspension Systems Showing All ComponentsC 635/C 635M 072The main runner
21、s provide direct support for cross runners, andmay support lighting fixtures and air diffusers. In addition, theacoustical tile may also be directly supported by the mainrunners. In some forms of mechanical ceiling suspensionsystems, the main runners are supported by hanger wiresattached directly to
22、 the existing structure. In other forms, themain runners (also referred to as “H” runners, “Z” bars, etc.)are installed perpendicular to carrying channels and are sup-ported by specially designed sheet metal or wire clips attachedto the carrying channels.3.1.1.11 nailing bar or furring barthe contin
23、uous sheetmetal strips to which a backing board is attached using eithernails or screws (Fig. 1c). The nailing bars are installedperpendicular to and supported by the carrying channels.3.1.1.12 non-interlockinga ceiling system that does notcomply with the specifications stated in the definition ofin
24、terlocking.3.1.1.13 splinea strip of metal or fiber inserted in the kerfsof adjacent acoustical tile to form a concealed mechanical jointseal (Fig. 1b).3.1.1.14 twistthe angle of rotation measured in a trans-verse plane between the two end cross sections of a mainrunner, cross runner, or wall moldin
25、g which has been perma-nently deformed during the process of manufacturing (Fig. 2).3.1.1.15 vertical plane (of a structural component of aceiling suspension system)a plane perpendicular to the planeof the ceiling which passes through the centroidal axis of themember (Fig. 2).3.1.1.16 wall molding t
26、he edge angles or channels of amechanical ceiling suspension system that are attached to awall (Fig. 1, a and b). The wall molding provides support forthe acoustical tile, main runners and cross runners that arelocated at the periphery of the ceiling.4. Classification4.1 The structural performance r
27、equired from a ceilingsuspension system shall be defined by the specifying authorityin terms of a suspension system structural classification.4.1.1 The structural classification of ceiling suspensionsystems shall be based on the load-carrying capacity of themain runners of the structural network. Lo
28、ad-carrying capacityas used herein is based on the more stringent requirement ofesthetic acceptance rather than the less confining prevention ofstructural failure. The criterion is the arbitrary but widelyestablished limit of deflection to1360 of the span betweensupports.4.1.2 The load-carrying capa
29、city shall be the maximumuniformly distributed load (pounds per linear foot N/m) thata simply supported main runner section having a span length ofFIG. 2 Diagrams Showing Camber, Bow, and TwistC 635/C 635M 0734 ft, 0 in. 1200 mm is capable of supporting without themid-span deflection exceeding 0.133
30、 in. 3.33 mm or1360 ofthe 4 ft, 0 in. 1200 mm span length, as tested in accordancewith the method described in Section 8.4.1.3 The structural classification or grade of ceiling sus-pension systems shall be determined by the capability of mainrunners or nailing bars to support a uniformly distributed
31、 load.These classifications shall be:4.1.3.1 Light-Duty Systems, used where ceiling loads otherthan acoustical tile or lay-in panels are not anticipated, such asresidential and light commercial structures.4.1.3.2 Intermediate-Duty Systems, used where ceilingloads other than acoustical tile or lay-in
32、 panels (light fixtures,air diffusers, etc.) are anticipated, such as ordinary commercialstructures.4.1.3.3 Heavy-Duty Systems, used where the quantities andweights of ceiling fixtures (lights, air diffusers, etc.) are greaterthan those for an ordinary commercial structure.4.1.4 For the purpose of d
33、etermining the structural classifi-cation of main runner members as covered in 4.1.2, theirsimple-span, minimum load-carrying capabilities, when testedin accordance with the test method described in Section 10,shall be listed as shown in Table 1 and Table 2.4.2 Cross runners shall be capable of carr
34、ying the loadspecified by the manufacturer without exceeding the maximumallowable deflection equal to1360 of its span.4.3 The design and definition of the suspension system shallbe the responsibility of the manufacturer. Included is selectionof appropriate materials, metal thicknesses, dimensions of
35、necessary component section configurations, design of specialhanger and assembly devices, and provision for whateveraccessory items are needed to ensure satisfactory ceilingperformance within the scope of this specification.4.3.1 System manufacturers may provide supplementarydata describing load def
36、lection capabilities of main runners ineach classification for spans other than 4 ft 1200 mm.4.4 Where specialized loading conditions that are outsidethe scope of this specification exist, the manufacturer should beconsulted for his recommendations; and, he may furnishengineering data as required. S
37、pecification or design of super-structure anchors or fasteners are not the responsibility of theceiling system manufacturer unless specified by the ceilingsystem manufacturer as part of the suspension system.5. Dimensional Tolerance5.1 Suspension system structural members shall conform tothe followi
38、ng tolerance requirements:5.1.1 Metal Thickness:5.1.1.1 For steel systems the thickness of metal used in mainrunners, cross runners, wall moldings, splines or nailing barsshall be stated by the suspension system manufacturer inFIG. 3 Load-Carrying Test Configuration for Inch/Pound UnitsFIG. 4 Load-C
39、arrying Test Configuration for Inch/Pound UnitsC 635/C 635M 074published literature. The thickness in thousandths of an inch ofmetal and the allowable thickness variation for the componentshall be stated.5.1.1.2 For aluminum systems the thickness of metal used inmain runners, cross runners, wall mol
40、dings, or splines shall bestated by the suspension system manufacturer in publishedliterature. The thickness in thousandths of an inch of metal andthe allowable thickness variation for the component shall bestated.5.1.2 Straightness:5.1.2.1 The amount of bow, camber, or twist in mainrunners, cross r
41、unners, wall molding, splines, or nailing bars ofvarious lengths shall not exceed the values shown in Table 3.5.1.2.2 Main runners, cross runners, wall moldings, splines,or nailing bars of ceiling suspension systems shall not containlocal kinks or bends.5.1.3 Length:5.1.3.1 The variation in the spec
42、ified length of main runnersections or cross runner sections that are part of an interlockinggrid system shall not exceed 60.010 in./4 ft 0.25 mm/1200mm.5.1.3.2 The variation in the specified spacing of slots orother cutouts in the webs of main runners or cross runners thatare employed in assembling
43、 a ceiling suspension grid systemshall not exceed 60.010 in. 0.25 mm.5.1.4 Over-all Cross-section Dimensions:5.1.4.1 For steel systems, the overall height of the crosssection of main runners, cross runners, wall molding, or nailingbar shall be the specified dimensions 60.030 in. 0.75 mm.The width of
44、 the cross section of exposed main runners or crossrunners shall be the specified dimension 60.008 in. 0.20 mm.5.1.4.2 For aluminum systems, the overall height of thecross section and the allowable variation of main runners, crossrunners, or wall molding shall be stated by the suspensionsystem manuf
45、acturer in published literature and price lists. Thewidth and allowable variation of the cross section of exposedmain runners or cross runners shall be similarly stated.5.1.5 Section Squareness:5.1.5.1 Intersecting webs and flanges of structural members(“I”,“ T”, or “Z” sections) shall form angles b
46、etween them of906 2. If deviations from squareness at more than one suchTABLE 1 Minimum Load-Carrying Capabilities of Main Runners - Inch/Pound UnitsSuspensionSystemDutyClassificationAppliedLoad (P)EquivalentUniformLoadAllowable MidspanDeflection (d)lb lb/ft in.Direct HungLight 5.0 5.0 0.133Intermed
47、iate 12.0 12.0 0.133Heavy 16.0 16.0 0.133Indirect HungLight 2.0 2.0 0.133Intermediate 3.5 3.5 0.133Heavy 8.0 8.0 0.133Furring BarLight 4.5 4.5 0.133Intermediate 6.5 6.5 0.133Heavy . . .d=span/360TABLE 2 Minimum Load-Carrying Capabilities of Main Runners - SI unitsSuspensionSystemDutyClassificationAp
48、plied Load(P)EquivalentUniformLoadAllowable MidspanDeflection (d)N N/m mm.Direct HungLight 22.7 75.7 3.33Intermediate 54.3 181.0 3.33Heavy 72.5 241.7 3.33Indirect HungLight 9.1 30.3 3.33Intermediate 15.9 53.0 3.33Heavy 36.3 121.0 3.33Furring BarLight 20.4 68.0 3.33Intermediate 29.4 98.0 3.33Heavy .
49、. .d=span/360Equivalent Uniform Load (n/m) obtained by the following relationship: P/0.3 mTABLE 3 Straightness Tolerances of Structural Members ofSuspension SystemsDeformation Straightness TolerancesBow132 in. 0.80 mm in any 2 ft 600 mmCamber132 in. 0.80 mm in any 2 ft 600 mmTwist 1 in any 2 ft 600 mmC 635/C 635M 075intersection are additive with respect to their use in a ceiling,the total angle shall not be greater than 2.5.1.5.2 The ends of structural members that abut or intersectother members in exposed grid systems shal
