1、BSI Standards PublicationBS 8597:2015Steels for the reinforcementof concrete Reinforcementcouplers Requirements andtest methodsPublishing and copyright informationThe BSI copyright notice displayed in this document indicates when the documentwas last issued. The British Standards Institution 2015Pub
2、lished by BSI Standards Limited 2015ISBN 978 0 580 83058 7ICS 77.140.15The following BSI references relate to the work on this document:Committee reference ISE/104Draft for comment 14/30283495 DCPublication historyFirst published August 2015Amendments issued since publicationDate Text affectedBS 859
3、7:2015 BRITISH STANDARDContentsForeword ii1 Scope 12 Normative references 13 Terms, definitions and symbols 14 Requirements 35 Testing of mechanical splices 56 Test report 97 Evaluation of conformity 10AnnexesAnnex A (informative) Stainless steel couplers 12Annex B (informative) High cycle elastic f
4、atigue testing 13Annex C (informative) Example of calculation of 99% and 95% characteristicstrength based on test results 14Bibliography 16List of figuresFigure 1 Principle of measurement of tensile properties 6Figure 2 Load cycle diagram for the high cycle fatigue test 8Figure B.1 Shape of the desi
5、gn S-N fatigue strength curve for mechanicalcouplers in accordance with BS EN 1992-1-1 13List of tablesTable 1 Symbols 3Table2Tensile strength requirements for mechanical splices 4Table3Testing frequency 11Table A.1 Tensile strength requirements for mechanical splices in stainlesssteel 12Table B.1 D
6、esign parameters for S-N curves for reinforcing steel in accordancewith BS EN 1992-1-1 13Table B.2 Basis of fatigue testing specification for highway schemes in theUK 14Table C.1 Coefficient, k1, as a function of number of tested samples 15Table C.2 Coefficient, k2, in Equation C.2 as a function of
7、number of testedsamples 15Summary of pagesThis document comprises a front cover, an inside front cover, pages i to ii,pages 1 to 16, an inside back cover and a back cover.BRITISH STANDARD BS 8597:2015 The British Standards Institution 2015 iForewordPublishing informationThis British Standard is publ
8、ished by BSI Standards Limited, under licence fromThe British Standards Institution, and came into effect on 31 August 2015. It wasprepared by Technical Committee ISE/104, Concrete reinforcing and pre-stressingsteels. A list of organizations represented on this committee can be obtained onrequest to
9、 its secretary.Information about this documentProduct certification. Users of this British Standard are advised to consider thedesirability of third-party certification of product conformity with this BritishStandard. Users seeking assistance in identifying appropriate conformityassessment bodies or
10、 schemes may ask BSI to forward their enquiries to therelevant association.Test laboratory accreditation. Users of this British Standard are advised toconsider the desirability of selecting test laboratories that are accredited toBS EN ISO/IEC 17025 by a national or international accreditation body.
11、Presentational conventionsThe provisions of this standard are presented in roman (i.e. upright) type. Itsrequirements are expressed in sentences in which the principal auxiliary verb is“shall”.Commentary, explanation and general informative material is presented insmaller italic type, and does not c
12、onstitute a normative element.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legalobligations.BRITISH STANDARD
13、BS 8597:2015ii The British Standards Institution 20151 ScopeThis British Standard specifies requirements and test methods for steelreinforcement couplers (hereafter called couplers) to be used for the mechanicalsplicing of steel reinforcing bars. It specifies requirements for couplers to beused for
14、mechanical splices in reinforced concrete structures underpredominantly static loads and additional requirements for couplers to be usedin elements of structures subject to high cycle elastic fatigue loading. It alsospecifies requirements for the evaluation of conformity of couplers.This British Sta
15、ndard does not specify requirements for couplers which are to beused for mechanical splices in reinforced concrete structures subject to low cycleloading in the elastic-plastic range.This British Standard specifies performance requirements for couplers. Thecouplers are tested as part of a mechanical
16、 splice between two lengths ofreinforcing steel, manufactured in accordance with BS 4449 or BS 6744. Theperformance tests specified are therefore for mechanical splices incorporatingthe coupler being assessed. The requirements of this standard apply to themanufacture of couplers and not the assembly
17、 or installation of mechanicalsplices on site.NOTE Instructions for assembly or installation of couplers can be obtained from themanufacturer.2 Normative referencesThe following referenced documents are indispensable for the application ofthis document. For dated references, only the edition cited a
18、pplies. For undatedreferences, the latest edition of the referenced document (including anyamendments) applies.BS 4449, Steel for the reinforcement of concrete Weldable reinforcing steel Bar, coil and decoiled product SpecificationBS EN ISO 7500-1, Metallic materials Verification of static uniaxial
19、testingmachines Part 1: Tension/compression testing machines Verification andcalibration of the force-measuring systemBS EN ISO 9513:2012, Metallic materials Calibration of extensometer systemsused in uniaxial testingBS EN ISO 15630-1:2010, Steel for the reinforcement and prestressing ofconcrete Tes
20、t methods Part 1: Reinforcing bars, wire rod and wireBS ISO 16020, Steel for the reinforcement and prestressing of concrete Vocabulary3 Terms, definitions and symbols3.1 Terms and definitionsFor the purposes of this British Standard, the terms and definitions given inBS ISO 16020 and the following a
21、pply.3.1.1 characteristic valuevalue of a material or product property having a prescribed probability of notbeing attained in a hypothetical unlimited test seriesNOTE This value generally corresponds to a specific fractile of the assumedstatistical distribution of the particular property of the mat
22、erial or product.BRITISH STANDARD BS 8597:2015 The British Standards Institution 2015 13.1.2 couplerdevice for the mechanical connection of two lengths of reinforcing barproviding a transfer of tension and/or compression loads from one bar tothe otherNOTE Also known as a reinforcement coupler.3.1.3
23、coupler length (L1)actual length of the coupler, including all load-transferring parts, and includinglock nuts, if any3.1.4 extension measurement deviceassembly consisting of a device or devices for the measurement of extension andany system used to fix it/them to a mechanical splice3.1.5 length of
24、mechanical splice (L)coupler length plus two times the nominal bar diameter at each end of thecouplerNOTE This is a conventionally agreed definition taking into account the affectedzone in an approximate way.3.1.6 mechanical splicecomplete assembly of a coupler including any additional intervening m
25、aterialor other components providing a connection between two reinforcing bars(and including the length of reinforcing steel, L2, affected by the connection ateither end)3.1.7 qualification testinitial type tests performed on a mechanical splice system3.1.8 reference barlength of reinforcing bar fro
26、m the same bar as used for the mechanical splice,tested for comparison with the performance of the splice3.1.9 slippermanent change in the length of a mechanical splice after being loaded to adefined load level and unloaded to zero3.1.10 stress ratioratio of the minimum stress to the maximum stress
27、in one cycle of loading in afatigue test3.1.11 sub-assemblypair of load-transmitting components where a coupler consists of more than twoload-transmitting componentsBRITISH STANDARDBS 8597:20152 The British Standards Institution 20153.2 SymbolsFor the purposes of this British Standard, the symbols i
28、n Table 1 apply.Table 1 SymbolsSymbol Unit DesignationAgt% Percentage total elongation at maximum tensile force, Fmaxd mm Nominal diameter of the reinforcing barFmaxN Maximum tensile forceN Specified number of load cycles in axial load fatigue testReMPaA)Characteristic yield strength of the reinforc
29、ing barRp0.2MPa Characteristic 0.2% proof strength, non-proportional extension, of thereinforcing barRmMPa Tensile strength of the reinforcing bar(Rm/Re) Characteristic tensile/yield strength ratio of the reinforcing bar(Rm/Rp0.2) Characteristic tensile/proof strength ratio of the reinforcing bar2a=
30、 _rskMPa Stress range of a high cycle fatigue testmaxMPa Maximum stress in a high cycle fatigue testminMPa Minimum stress in a high cycle fatigue testA)1 MPa = 1 N/mm24 Requirements4.1 GeneralThe requirements shall apply to the coupler, although the assessment ofconformity of the coupler is carried
31、out on a mechanical splice that has beenassembled in accordance with the manufacturers written instructions, usingreinforcing bar of the grade for which the coupler is qualified (see Table 2).When tested in accordance with Clause 5, the specified requirements shall bemet for the following:a) slip un
32、der static forces; andb) strength under static forces.Optionally, when tested in accordance with 5.5, the specified requirements shallbe met for performance under high cycle fatigue loading in the elastic range.In addition, the following shall be recorded:1) ductility under static forces; and2) iden
33、tification and marking.NOTE If stainless steel couplers are specified then these should be used inaccordance with the recommendations set out in Annex A.BRITISH STANDARD BS 8597:2015 The British Standards Institution 2015 34.2 Slip under static forces4.2.1 GeneralThe slip across the mechanical splic
34、e shall be taken to be the residual extension(in tension) or contraction (in compression) of the mechanical splice afterloading the splice to a load equivalent to 0.65 Reand unloading to zero.NOTE Slip is usually measured after loading and then unloading in tension.The measurement of slip in compres
35、sion is only required where this is specified bythe designer.4.2.2 Slip requirement in tension or compressionWhen tested in accordance with 5.3, the slip value measured for a simplecoupler, consisting of no more than two load-transmitting components, shall notexceed 0.10 mm.For couplers consisting o
36、f more than two load-transmitting components, whentested in accordance with 5.3, either:a) the slip value shall not exceed 0.10 mm; orb) the strain measured across the splice at a load equivalent to 0.65 Reshallnot exceed 0.16% or the actual value measured on the reference bar,whichever is the great
37、er. In addition for qualification testing the slipmeasured across each sub-assembly after unloading shall notexceed 0.10 mm.4.3 Strength and ductility under static forces4.3.1 StrengthWhen tested in accordance with 5.4, the tensile strength of the mechanicalsplice shall meet the requirements in Tabl
38、e 2.If couplers are used to connect bars of different diameters, the tensile strengthshall be calculated using the nominal cross-sectional area of the smallerreinforcing bar.4.3.2 DuctilityWhen tested in accordance with 5.4, the Agtdeveloped in the bar shall bemeasured and recorded. The Agtshall not
39、 be a cause for rejection.NOTE Ductility of the coupler itself is not subject to testing; only the ductility ofthe splice.4.4 Failure location and modeThe location of the failure and its mode shall be reported according to therequirements of 5.4.4.Table 2 Tensile strength requirements for mechanical
40、 splicesReinforcing bar standard Grade Minimum tensile strength, Rm(MPa)BS 4449 B500A 525BS 4449 B500B 540BS 4449 B500C 575BRITISH STANDARDBS 8597:20154 The British Standards Institution 20154.5 Properties under high cycle fatigue loading in the elasticrangeWhen tested in accordance with 5.5, the hi
41、gh cycle elastic fatigue performanceshall meet the specified requirement(s).Where the specification of the requirement(s) for performance under high cyclefatigue is by means of a specified minimum number of cycles to be sustainedunder specified fatigue loading conditions, testing shall be carried ou
42、t inaccordance with 5.5.When tested in this way, the following acceptance criteria shall be applied. If all test samples resist the fatigue loading, the test is passed. If one test sample fails the test, five additional samples of the same typeand diameter as those that have failed shall be tested.
43、If all five additionaltest samples pass, the test is passed. If two or more test samples fail the fatigue test, the test is failed.NOTE Annex B gives the specified fatigue test requirements for highway structureson UK motorways and trunk roads, and for use of couplers in designs in accordancewith BS
44、 EN 1992-1-1. Other fatigue performance requirements can be agreedbetween the client and the manufacturer.Alternatively, the performance of a mechanical splice under high cycle stresses ofdifferent amplitudes can be characterized by an S-N diagram; if an S-N diagramis determined, the provisions in 5
45、.5.4 shall be applied. Where this option isselected, the decision on the suitability of the splice under high cycle elasticfatigue loading shall be agreed between the client and the manufacturer foreach contract.4.6 Identification and markingEach coupler shall be legibly and durably marked (e.g. har
46、d stamped) with themanufacturers identification, the coupler type, the nominal bar size for which itis intended and a batch mark for traceability purposes. Each coupler shall betraceable back to its production data.4.7 Installation instructionsThe manufacturer shall provide clear, written installati
47、on instructions. Thedescribed processing of the couplers shall be achievable under construction siteconditions.5 Testing of mechanical splices5.1 GeneralAll tests shall be carried out on mechanical splices assembled in accordance withthe manufacturers written instructions. In cases of dispute, test
48、specimens shallbe tested in an artificially aged condition. Where required, a reference samplefrom the same bar used for the splice shall be tested to determine its actualmechanical properties. A reference bar shall always be tested in the case ofqualification testing and continuous independent test
49、ing. The test methods tobe carried out shall be:a) slip test;b) tensile test; andc) high cycle fatigue test (optional).NOTE 1 The principle of measurement of tensile properties is shown in Figure 1.BRITISH STANDARD BS 8597:2015 The British Standards Institution 2015 5NOTE 2 Artificially aged means heating the splice to 100 C, maintaining at thistemperature 10 C for a period of 1 h 15 min and then cooling in still air toambient temperature.NOTE 3 It is advisable to retain a reference bar for all tests for inv
