AS NZS 1664 1 Supp 1-1997 Aluminium structures - Limit state design - Commentary (Supplement to AS NZS 1664 1 1997)《铝结构 限定情况设计 注释（AS NZS 1664 1 1997的补充）》.pdf

1、AS/NZS 1664.1 Supp1:1997AS/NZS 1664.1Supplement 1:1997Aluminium structuresPart 1: Limit state designCommentary(Supplement 1 toAS/NZS 1664.1:1997)Accessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 2006AS/NZS 1664.1 Supp1:1997This Joint Australian/New Zealand Standard was prepared

2、 by Joint TechnicalCommittee BD/50, Aluminium Structures. It was approved on behalf of the Councilof Standards Australia on 27 June 1997 and on behalf of the Council of StandardsNew Zealand on 11 July 1997. It was published on 5 September 1997.The following interests are represented on Committee BD/

3、50:The Association of Consulting Engineers, AustraliaAluminium Development CouncilAustralian Building Codes BoardInstitution of Professional Engineers New ZealandUniversity of SydneyReview of Standards. To keep abreast of progress in industry, Joint Australian/New Zealand Standards are subject to pe

4、riodic review and are kept up to date by the issueof amendments or new editions as necessary. It is important therefore that Standards usersensure that they are in possession of the latest edition, and any amendments thereto.Full details of all Joint Standards and related publications will be found

5、in the StandardsAustralia and Standards New Zealand Catalogue of Publications; this information issupplemented each month by the magazines The Australian Standard and StandardsNew Zealand, which subscribing members receive, and which give details of newpublications, new editions and amendments, and

6、of withdrawn Standards.Suggestions for improvements to Joint Standards, addressed to the head office of eitherStandards Australia or Standards New Zealand, are welcomed. Notification of anyinaccuracy or ambiguity found in a Joint Australian/New Zealand Standard should be madewithout delay in order t

7、hat the matter may be investigated and appropriate action taken.Accessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 2006AS/NZS 1664.1 Supp1:1997AS/NZS 1664.1Supplement 1:1997Aluminium structuresPart 1: Limit state designCommentary(Supplement 1 toAS/NZS 1664.1:1997)Originated in A

8、ustralia as part of AS 1664 1975.Previous Australian edition AS 1664 1979.Jointly revised and designated AS/NZS 1664.1 Supplement 1:1997.Incorporating:Amdt 11999PUBLISHED JOINTLY BY:STANDARDS AUSTRALIA1 The Crescent,Homebush NSW 2140 AustraliaSTANDARDS NEW ZEALANDLevel 10, Radio New Zealand House,15

9、5 The Terrace,Wellington 6001 New ZealandISBN 0 7337 1283 5Accessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 2006AS/NZS 1664.1 Supp1:1997 2PREFACEThis Commentary was prepared by the Standards Australia/Standards New ZealandCommittee BD/50, Aluminium Structures. It is intended t

10、o be read in conjunction withAS/NZS 1664.1, Aluminium Structures, Part 1: Limit state design, but it does not form anintegral part of that Standard.This Commentary is not intended to provide a general primer to probability-based limitstate design (LSD) criteria. This is provided in Reference 2 and i

11、n the further referenceswhich are cross-referenced numerically in the text and listed at the end of this document.The objective of this Commentary is to give an explanation of the reasons for therecommended capacity factors in AS/NZS 1664.1 and to provide background material tothe requirements of th

12、at Standard.The clause numbers and titles used in this Commentary are the same as those inAS/NZS 1664.1 except that they are prefixed by the letter C.Gaps in the numerical sequence of this Commentarys clause numbering means that noexplanation of or background to the missing clause(s) is necessary. C

13、opyright STANDARDS AUSTRALIA/ STANDARDS NEW ZEALANDUsers of Standards are reminded that copyright subsists in all Standards Australia and Standards New Zealand publications and software.Except where the Copyright Act allows and except where provided for below no publications or software produced byS

14、tandards Australia or Standards New Zealand may be reproduced, stored in a retrieval system in any form or transmitted by any meanswithout prior permission in writing from Standards Australia or Standards New Zealand. Permission may be conditional on anappropriate royalty payment. Australian request

15、s for permission and information on commercial software royalties should be directed tothe head office of Standards Australia. New Zealand requests should be directed to Standards New Zealand.Up to 10 percent of the technical content pages of a Standard may be copied for use exclusively in-house by

16、purchasers of theStandard without payment of a royalty or advice to Standards Australia or Standards New Zealand.Inclusion of copyright material in computer software programs is also permitted without royalty payment provided such programsare used exclusively in-house by the creators of the programs

17、.Care should be taken to ensure that material used is from the current edition of the Standard and that it is updated whenever the Standardis amended or revised. The number and date of the Standard should therefore be clearly identified.The use of material in print form or in computer software progr

18、ams to be used commercially, with or without payment, or in commercialcontracts is subject to the payment of a royalty. This policy may be varied by Standards Australia or Standards New Zealand at any time.Accessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 20063 AS/NZS 1664.1 Su

19、pp1:1997CONTENTSPageSECTION C1 GENERALC1.4 REFERENCED DOCUMENTS . 4SECTION C3 GENERAL DESIGN RULESC3.4 FACTORED LIMIT STATE STRESSES 9SECTION C5 MECHANICAL CONNECTIONSC5.1 BOLTED AND RIVETED CONNECTIONS . 17SECTION C6 FABRICATIONC6.6 PAINTING . 18SECTION C7 WELDED CONSTRUCTIONC7.2 FILLER WIRE 19SECT

20、ION C8 TESTINGC8.3 TEST REQUIREMENTS 20C8.5 PROOF TESTING . 20C8.6.2 Test load . 20REFERENCES 21Accessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 2006AS/NZS 1664.1 Supp1:1997 4STANDARDS AUSTRALIA/STANDARDS NEW ZEALANDAustralian/New Zealand StandardAluminium structuresPart 1: Li

21、mit state designCommentary(Supplement 1 to AS/NZS 1664.1: 1997)SECTION C1 GENERALC1.4 REFERENCED DOCUMENTS The Standards listed in Clause 1.4 are subject torevision from time to time. A check should be made with Standards Australia or StandardsNew Zealand, as appropriate, as to the currency of any d

22、ocument referenced in the text.COPYRIGHTAccessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 20065 AS/NZS 1664.1 Supp1:1997SECTION C3 GENERAL DESIGN RULESINTRODUCTION The general procedure of applying the limit state design (LSD)method for aluminium building structures consists of

23、 the following steps:(a) Determine the stress due to the factored loads, f, by conventional elastic structuralanalysis. The factored loads are the specified dead, live, wind, rain, snow orearthquake loads multiplied by the load factors given in Clause 2.4.(b) Compute the factored limit state stress

24、FLfrom Clause 3.4 and verify thatFL fClause 3.4 gives the capacity factor and the limit state stress FLfor a variety ofcommonly encountered aluminium structural members and elements. The limit statestress FLis dependent on the material properties and the member geometry. It reflects theultimate load

25、-carrying capacity of the member or element, be that yield, fracture,plastification, buckling or crippling. The limit state stresses in these LSD criteria areidentical to those given in AS/NZS 1664.2 by setting the factors of safety equal to unityin the various formulas given in Clause 3.4 of AS/NZS

26、 1664.2.The capacity factor accounts for the uncertainties of determining the limit state stress. Itis computed by the method of first-order second-moment probabilistic analysis presentedin Reference 2 for a target reliability index of T= 2.5 for the yield limit state andT= 3.0 for the fracture limi

27、t state. Below is a detailed account presenting the backgroundfor each of the capacity factors used in Clause 3.4 of the LSD criteria.Prior to this detailed account it will be instructive to discuss in a simple manner the basicconcepts of probabilistic design. Failure is defined when the resistance,

28、 as characterizedby a limit state, is less than or equal to the load effect on the structural element. The loadeffect in these LSD criteria for aluminium structures is characterized by the stresscomputed by elastic analysis from the forces acting on the structure. Both the resistance Rand the load e

29、ffect Q are random quantities (see Figure C1).FIGURE C1 SCHEMATIC REPRESENTATION OF PROBABILITIES OF THE LOADEFFECT AND THE RESISTANCELimit states are either ultimate or serviceability limit states. These LSD criteria pertain tothe ultimate limit states of yield, fracture, plastification, buckling a

30、nd crippling, althoughthe serviceability limit states of deflection and the appearance of buckling are alsofeatures (see Section 4).COPYRIGHTAccessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 2006AS/NZS 1664.1 Supp1:1997 6Failure is then not necessarily the total collapse of the

31、 member, but the reaching of apractically defined ultimate limit state. It occurs when R 1.2The capacity factor thus varies linearly as the slenderness parameter . The valuesresulting from the use of cc(Equation C3(31) is the LSD design criteria are shown asthe solid curve in Figure C5. The target v

32、alue of T= 2.5 is fairly closely approximated.FIGURE C5 RELIABILITY WITH LINEARLY VARYING ccCOPYRIGHTAccessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 2006AS/NZS 1664.1 Supp1:1997 14In Reference 5 considerable work was done on one additional aspect of column design.Real pinned-

33、end columns rarely exist in practice. Even nominally pinned columns havesome end restraint, and most columns are actually restrained by the connection to the baseor to members framing into their ends. Furthermore, intentionally axially loaded membersare also rare, most compression members being actu

34、ally beam-columns subjected to bothcompression and bending. It was shown that each of these effects has a conservativeinfluence and thus tends to increase . A number of additional cases were studied,showing the same general trend of a somewhat increased value of due to restraint.C3.4.9 to C3.4.25 Th

35、e statistical basis for selecting the values in Clauses 3.4.9to 3.4.25 is presented in Reference 3. The same values of ywere recommended as fortension of the corresponding member types of Clauses 3.4.3 to 3.4.5, thus equating thereliability of short compressed members and elements to that underlying

36、 tension elements.The relevant data for choosing the values, which apply to buckling or crippling typelimit states, are summarized in Tables C3.4.9.1, C3.4.9.2, C3.4.9.3, and C3.4.9.4.For certain alloys and specifications sections, a negative S1slenderness limit may resultfrom the equations given in

37、 Table 3.4(C). In such cases S1should be taken as 0.TABLE C3.4.9.1SUMMARY OF STATISTICAL DATASection inReference 1LimitstateFS PmMmFmVpVMVFVRCategory3.4.1, 2, 3, 4 Y ny1.0 1.10 1.0 1.10 0 0.06 0.05 0.08 AU ktnu1.0 1.10 1.0 1.10 0 0.06 0.05 0.08 B3.4.8, 9 Y kcny1.0 1.10 1.0 1.10 0 0.06 0.05 0.08 CB n

38、u1.0 1.0 1.0 1.0 0.05 0.06 0.05 0.09 D3.4.10 Y kcny1.0 1.10 1.0 1.10 0 0.06 0.05 0.08 CIB nu1.0 1.0 1.0 1.0 0.05 0.06 0.05 0.09 DEB nu1.24 1.0 1.0 1.24 0.27 0.06 0.05 0.28 E3.4.11, 13,14Y ny1.0 1.10 1.0 1.10 0 0.06 0.05 0.08 AB ny1.03 1.0 1.0 1.03 0.11 0.06 0.05 0.13 F3.4.12, 16.1 Y ny1.0 1.10 1.0 1

39、.10 0 0.06 0.05 0.08 AIB ny1.01 1.0 1.0 1.01 0.05 0.06 0.05 0.09 GEB ny1.24 1.0 1.0 1.24 0.27 0.06 0.05 0.28 H3.4.15, 16,17Y ny1.0 1.10 1.0 1.10 0 0.06 0.05 0.08 AB ny1.0 1.0 1.0 1.0 0.05 0.06 0.05 0.09 I3.4.20 Y ny1.0 1.10 1.0 1.10 0 0.06 0.05 0.08 AIB ny1.07 1.0 1.0 1.07 0.09 0.06 0.05 0.12 JEB ny

40、0.93 1.0 1.0 0.93 0.09 0.06 0.05 0.12 KCOPYRIGHTAccessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 200615 AS/NZS 1664.1 Supp1:1997TABLE C3.4.9.2LIMIT STATE CATEGORIESCategory FS R/RnVRDescriptionA 1.65 1.10 0.08 yield in tensionB 1.95 1.10 0.08 fracture in tensionC 1.82 1.10 0.0

41、8 yield in compressionD 1.95 1.00 0.09 buckling of column components inelasticcolumn bucklingE 1.95 1.24 0.28 elastic column bucklingF 1.65 1.03 0.13 beam buckling, overallG 1.65 1.01 0.09 inelastic local bucklingH 1.65 1.24 0.28 elastic local bucklingI 1.65 1.00 0.09 local buckling of beamsJ 1.65 1

42、.07 0.12 inelastic shear bucklingK 1.65 0.93 0.12 elastic shear bucklingTABLE C3.4.9.3RELIABILITY INDICES FOR ASD SPECIFICATIONCategoryfor D/L = 0.1 for D/L = 0.2A 2.46 2.64B 3.16 3.40C 2.87 3.09D 2.72 2.92E 2.44 2.51F 2.01 2.13G 2.08 2.22H 1.98 2.03I 2.04 2.18J 2.20 2.34K 1.65 1.75COPYRIGHTAccessed

43、 by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 2006AS/NZS 1664.1 Supp1:1997 16TABLE C3.4.9.4CAPACITY FACTORS FOR LSD SPECIFICATIONCategoryTarget Target II*for D/L = 0.2for D/L = 0.1 for D/L = 0.2 Rounded offFor primary structural elements For secondary elementsA 2.5 0.94 0.96 0.95 2

44、.0 1.07B 3.0 0.83 0.86 0.85 2.5 0.96C 2.5 0.94 0.96 0.95 2.0 1.07D 2.5 0.85 0.86 0.85 2.0 0.97E 2.5 0.78 0.79 0.80 2.0 0.94F 2.5 0.83 0.85 0.85 2.0 0.96G 2.5 0.85 0.87 0.85 2.0 0.98H 2.5 0.78 0.79 0.80 2.0 0.94I 2.5 0.85 0.86 0.85 2.0 0.97J 2.5 0.88 0.89 0.90 2.0 1.01K 2.5 0.76 0.78 0.80 2.0 0.88* w

45、here 1.0 for secondary elements. recommended for use in LSD Spec.COPYRIGHTAccessed by ISONET - CHINA STATE BUREAU OF TECHNICAL SUPERVIS on 06 Jun 200617 AS/NZS 1664.1 Supp1:1997SECTION C5 MECHANICAL CONNECTIONSC5.1 BOLTED AND RIVETED CONNECTIONSC5.1.1 General For mechanical connections of pre-painte

46、d aluminium structures seeParagraph C6.6.1.C5.1.2 Factored limit state loads The -factors used for bearing stresses inTable 5.1.2.4 were adopted from Clause 3.4.6. The value of = 0.65 for shear stress onrivets and bolts was determined by the following derivation. It was assumed that thetypical shear

47、 strength values for rivets given in Reference 10 represent mean values. Theratio of the mean to the minimum expected values was found to be 1:15. A coefficientof variation of 0.1 was assumed. It was also assumed that the nominal rivet area is equalto the mean, with a coefficient of variation of 0.1

48、. The mean shear capacity of a rivet isthus. . . C5(1)R = A Fsu=1.01.5AnFsunand. . . C5(2)With these statistics a calibration was performed using Equation 1, and for a D/L = 0.2 itwas found that ASD design gave = 3.9. The LSD design with = 0.65 gave = 4.0.COPYRIGHTAccessed by ISONET - CHINA STATE BU

49、REAU OF TECHNICAL SUPERVIS on 06 Jun 2006AS/NZS 1664.1 Supp1:1997 18SECTION C6 FABRICATIONC6.6 PAINTINGC6.6.1 General Mechanical connections of pre-painted aluminium structural membersmay be affected as follows:(a) Connecting by bolts The total film build between the two painted aluminiummembers may affect the torque retention of the connecting bolts. The retentiontorque loss may lead to loose connection and subsequently premature fatigue failureof bolts and aluminium members in the localized join area.In addition, the corrosion r