1、Designation: E 455 04Standard Test Method forStatic Load Testing of Framed Floor or Roof DiaphragmConstructions for Buildings1This standard is issued under the fixed designation E 455; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, the year 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method cover
3、s procedures designed (1)toevaluate the static shear capacity of a typical segment of aframed diaphragm under simulated loading conditions, and (2)to provide a determination of the stiffness of the constructionand its connections. A diaphragm construction is an assemblyof materials designed to trans
4、mit shear forces in the plane ofthe construction.1.2 No effort has been made to specify the test apparatus, asthere are a number that can be used as long as the needs of thetesting agency are met. If round-robin testing is to be con-ducted, test apparatus and testing procedures shall be mutuallyagre
5、ed upon in advance by the participants.1.3 The text of this standard contains notes and footnotesthat provide explanatory information and are not requirementsof the standard. Notes and footnotes in tables and figures arerequirements of this standard.1.4 The values stated in inch-pound units are to b
6、e regardedas the standard. The values given in parentheses are forinformation only.1.5 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 practices and
7、determine the applica-bility of regulatory limitations prior to use. For specificprecautionary statements, see Section 6.2. Referenced Documents2.1 ASTM Standards:2E 631 Terminology for Building Constructions3. Terminology3.1 For definitions of terms used in this standard, refer toTerminology E 631.
8、3.2 Symbols specific to this standard:E = modulus of elasticity of flange or web mate-rial, depending upon which material is heldconstant in a transformed section analysis, psi(or MPa)G = shear modulus of the web material, psi (orMPa)G8 = shear stiffness of the diaphragm obtainedfrom test (includes
9、shear deformation factorfor the connection system), lbf/in. (or N/mm)I = moment of inertia of the transformed sectionof the diaphragm based on webs or flanges,in.4(or mm4)L = total span of a simply supported diaphragm,in. (or mm)P = concentrated load, lbf (or N)Ru= maximum diaphragm reaction, lbf (o
10、r N)Su= ultimate shear strength of the diaphragm,lbf/ft (or N/m)a = span length of cantilever diaphragm, in. (ormm)b = depth of diaphragm, in. (or mm)t = thickness of web material, in. (or mm)w = uniform load, lbf/in. (or N/mm)Db= bending deflection of diaphragm, in. (or mm)Dk= empirical expression
11、for that portion of thediaphragm deflection contributed by the sheardeformation of the connection system, in. (ormm)Ds= pure shear deformation of diaphragm, in. (ormm)1This method is under the jurisdiction ofASTM Committee E06 on Performanceof Buildings and is the direct responsibility of Subcommitt
12、ee E06.11 on Horizontaland Vertical Structures/Structural Performance of Completed Structures.Current edition approved April 1, 2004. Published April 2004. Originallyapproved in 1976. Last previous edition approved in 1998 as E 455 98.2For referenced ASTM standards, visit the ASTM website, www.astm.
13、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, United States.Ds8 = appar
14、ent total shear deformation of the dia-phragm based on test (see section 8.1.2.2), in.(or mm). This factor includes both the pureshear deformation and that contributed bydistortion of the connection system.Dt= total deflection of diaphragm, in. (or mm)D1,2,_= deformation measured at Point 1, 2,_,in.
15、(or mm)4. Summary of Method4.1 The general purpose of this test method is to evaluatethe shear forces that can be carried by the web of a framed flooror roof diaphragm assembly by testing a simulation of theconstruction. The test method outlines basic procedures for thestatic load testing of these c
16、onstructions using simple beam orcantilever-type test specimens. Suggested specimen and testsetup details are provided, along with loading procedures,instrumentation, and evaluation methods.4.2 Construction:4.2.1 Diaphragm Performance AssumptionsThese dia-phragm assemblies, assumed to act as plate g
17、irders, spanbetween shear walls, moment bents, or other constructions thatfurnish the end or intermediate supports to the system. Thechord members of the assembly perpendicular to the line ofapplied load act as the flanges of the girder, and the plate orpanel elements act as the web.Aschematic drawi
18、ng of a simplespan diaphragm is shown in Fig. 1.4.2.2 ConnectionsThe performance of the diaphragm isinfluenced by the type and spacing of the panel attachmentsand perimeter anchorage. It is necessary to ensure that the typeof connection system used and its application as nearly aspossible duplicate
19、the system intended for use in the prototypestructure.4.3 DeformationsThe in-plane diaphragm deformation(s)shall be recorded. The total in-plane deformation of a dia-phragm consists of bending and shear deformation plus anyadditional deformation caused by distortion of the connectionsystem. Table 1
20、contains some useful deflection equations.5. Significance and Use5.1 Framed floor and roof systems are tested by this testmethod for static shear capacity. This test method will helpdetermine structural diaphragm properties needed for designpurposes.6. Apparatus6.1 Test Assembly:6.1.1 GeneralThe dia
21、phragm test assembly consists of aframe or framing system on which the elements comprising theweb of the diaphragm are placed. The elements are fastened tothe frame in a manner equivalent to their attachment in thefield. The assembly may be tested horizontally or vertically.Either a cantilever or a
22、simple span diaphragm assembly maybe used, with concentrated or distributed loading.6.1.2 Frame RequirementsThe frame is a part of the testassembly and shall consist of members of the same or similarmaterials as those intended for use in the prototype construc-tion. The test frame members shall be o
23、f equal or less strengththan those intended for use in the prototype construction. If thetest objective is to force failure to occur elsewhere in theassembly, make the test frame members stronger and note themodification in the test report. The frame shall be calibrated toestablish its load-deformat
24、ion characteristics before attachingthe diaphragm elements. If the frame has a stiffness equal to orless than 2 % of the total diaphragm assembly, no adjustmentof test results for frame resistance need be made. However, ifthe frame stiffness is greater than 2 % of the total assembly, thetest results
25、 shall be adjusted to compensate for frame resis-tance.6.1.2.1 Cantilever Frame (see Fig. 2)A pinned framereaction at corner (C) shall be provided to transfer thehorizontal force (P) through the diaphragm into the supportFIG. 1 Schematic of Simple Span DiaphragmE455042system. The pin shall be locate
26、d as close as possible to thediaphragm-to-frame contact plane to minimize warping of thediaphragm surface. A vertical reaction roller or rollers shall beprovided in the diaphragm plane at corner (H). The frame shallbe laterally supported at adjacent corners (D) and (E) on rollersand at other locatio
27、ns as necessary to prevent displacement ofthe diaphragm from the plane of testing, but not to restrictin-plane displacements.6.1.2.2 Simple Span Frame (see Fig. 3)In-plane reactionsshall be provided at points (E) and (H) as shown to resist theapplied test load or loads. The frame shall be supported
28、withrollers at points (C), (D), (E), and (H), and under each loadingpoint. Hold-downs with rollers shall be provided to preventdisplacement of the specimen from the plane of testing but notto restrict in-plane displacements. The diaphragm can also besupported by tension reactions at points (C) and (
29、D) instead ofreactions shown at points (E) and (H)inFig. 3.6.1.3 Diaphragm Size:6.1.3.1 Cantilever DiaphragmThe diaphragm shall betested on a span length a, as shown in Fig. 2, equal to or greaterthan the typical support spacing likely to be used in thebuilding. The test assembly shall not be less t
30、han 8 ft (2.4 m)in either length or width; nor shall it contain less than fourelements if the diaphragm consists of individual elements. Thediaphragm shall contain typical end and side joints for theelements.NOTE 1When the web of the diaphragm is made of individualelements, they might not be equally
31、 effective for the same span length iflaid perpendicular or parallel to the load direction.TABLE 1 Useful Deflection EquationsNOTEOther equations may be applicable depending on the number of load points used.Type of Beam Loading ConditionMaximum DeflectionsADbDsDs8Simple beam uniform load 5wL4/384EI
32、 wL2/8Gbt wL2/8G8bSimple beam third-point loadB23PL3/648EI PL/3Gbt PL/3G8bCantilever beam uniform load wa4/8EI wa2/2Gbt wa2/2G8bCantilever beam concentrated load at free end Pa3/3EI Pa/Gbt Pa/G8bAAt midspan of simple beam and free end of cantilever beam. Make appropriate adjustment in units as requi
33、red for compatibility when SI units are used.BFor bending deflection at the load points under a third-point load, use the following equation:Db at L/3!5 5PL3/162EI!NOTE 1s Dial gage or other deflection measuring device.NOTE 2Lateral restraint devices are not shown, and should not restrict movement i
34、n the plane of the diaphragm.FIG. 2 Plan of a Cantilever Beam Diaphragm Test with a Concentrated LoadE4550436.1.3.2 Simple Beam DiaphragmThe diaphragm lengthand depth shall be as shown in Fig. 3, where the dimensions aand b have the same connotation as above with a minimumdimension in either case of
35、 8 ft (2.4 m). The diaphragm shallcontain typical end and side joints for the elements.7. Safety Precautions7.1 Tests of this type can be dangerous. Equipment andfacilities must be designed with ample safety factors to ensurethat it is the specimen that fails and not the test apparatus orfacilities.
36、 Observers and sensitive instrumentation must be keptaway from diaphragms when loading to failure or in a loadrange where performance is unknown.8. Number of Tests8.1 A minimum of two specimens shall be tested to deter-mine the value of a given construction. If the plan of thediaphragm is unsymmetri
37、cal, the second test shall be run withthe specimen orientation reversed with respect to the loadapplication used on the first specimen. If the tests do not agreewithin 10 % of the lower value, a third specimen shall be testedwith this specimen oriented in the same manner as the weakerof the two prev
38、ious tests. A mean value is computed from thelowest two values of the three tests.8.2 Duplicate tests may be waived when a series of tests arebeing made to simulate a range of variables.9. Procedure9.1 Determination of Frame StiffnessDetermine the framestiffness prior to the application of the web e
39、lements. Load theframe in a manner similar to that intended for the completeddiaphragm. If the frame is a “standard” frame, determine thestiffness of the frame. If calculations show that the framestiffness is less than 2 % of the total diaphragm assembly, aseparate frame test is not required.9.2 Loa
40、ding Procedure for Complete DiaphragmApplythe loads to the diaphragm parallel to and as close as practicalto the place of contact between the diaphragm web and frame,in a manner duplicating, as far as practical, the in-serviceloading conditions. Choose the rate of load such that theanticipated full
41、design load level will be reached in not lessthan 10 min. Take at least ten sets of uniformly spaceddeflection readings prior to failure to establish the load-deformation curve. The rate of load application shall permitload and deformation readings to be recorded. Apply loads byhydraulic jacks that
42、have been previously calibrated, or byother suitable types of loading apparatus. Take account of theweight of the specimen and loading apparatus if it is antici-pated that the weights will affect the results. Measure defor-mations with dial gages or other suitable devices to establish anadequate loa
43、d-deformation curve. Measure deflections to thenearest 0.01 in. (0.2 mm). Load-measuring devices shall beNOTE 1s Dial gage or other deflection measuring device.NOTE 2Lateral restraint devices are not shown, and should not restrict movement in the plane of the diaphragm.FIG. 3 Plan of a Simple Beam D
44、iaphragm Test with Third-Point LoadingE455044accurate to within 62 %. At load levels such as approximatelyone third and two thirds of the estimated ultimate load, the loadmay be removed and the recovery of the diaphragm recordedafter 5 min. Maintain a record of the total length of time thediaphragm
45、is under load.10. Calculation10.1 Base evaluation on the mean values resulting fromtests of identical specimens or on the results of single tests ifonly one specimen is involved, in accordance with the provi-sions of Section 6. The following information is obtained fromthese tests:10.1.1 Ultimate Sh
46、ear StrengthCalculate the ultimateshear strength, Su, as follows:Su, lbf/ft 512 Rubor (1)Su, N/m 51000 Rub(2)where Ruis the maximum reaction at failure in a simplebeam test, or the maximum reaction acting parallel to theapplied load in a cantilever beam test, and b is the diaphragmdepth, as indicate
47、d in Figs. 2 and 3.10.1.2 Apparent Shear StiffnessAn apparent shear stiff-ness G8 may be determined for the entire assembly on the basisof an applied load at a reference load level below theproportional limit for use in deflection calculations. In thefollowing formulas Dbis determined using the appr
48、opriateequations from Table 1.10.1.2.1 For use in determining the apparent shear stiffness,calculate the total deflection at any load level, Dt, takingaccount of the support movements, as follows:Cantilever beam test: Dt5D32FD11abD21D4!G(3)Simple beam test: Dt5D21D32D12D4!2(4)where D1, D2, D3, and D
49、4are measured deformations withappropriate signs at locations indicated in Figs. 2 and 3, and a/bis the ratio of the diaphragm assembly dimensions. Theload-deformation curve can then be plotted on the basis of thetest results.10.1.2.2 Calculate the real (Ds) and apparent (Ds8) sheardeformations at any load level as follows:Ds5Dt2Db2Dk(5)Ds8 5Dt2Db(6)For the concentrated load conditions shown in Figs. 2 and 3,calculate the apparent shear stiffness, G8, of the diaphragm asfollows:G8 5PDs8SabD(7)The test setups and loading pattern used in Figs. 2 and 3 mayb
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