BS-EN-523-1997.pdf

BRITISH STANDARD BS EN 523:1997 Steel strip sheaths for prestressing tendons Terminology, requirements, quality control The European Standard EN 523:1997 has the status of a British Standard ICS 01.040.77; 01.040.91; 77.140.75; 91.080.40 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 02:02:53 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 523:1997 This British Standard, having been prepared under the direction of the Sector Board for Materials and Chemicals, was published under the authority of the Standards Board and comes into effect on 15 November 1997 © BSI 04-2000 ISBN 0 580 28665 7 National foreword This British Standard is the English language version of EN 523:1997. The UK participation in its preparation was entrusted by Technical Committee B/525, Building and civil engineering structures, to Subcommittee B/525/2, Structural use of concrete, which has the responsibility to: aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages 2 to 10 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 02:02:53 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 523:1997 © BSI 04-2000i Contents Page National forewordInside front cover Foreword2 Test of EN 5233 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 02:02:53 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ii blank Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 02:02:53 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 523 March 1997 ICS 77.140.75; 91.080.40 Descriptors: Prestressed concrete, cables, ropes, sheaths, protectors, strips, steels, plastics, classifications, specifications, quality control, marking English version Steel strip sheaths for prestressing tendons Terminology, requirements, quality control Gaines en feuillard dacier pour câbles de précontrainte Terminologie, prescriptions, contrôle de qualité Hüllrohre aus Bandstahl für Spannglieder Begriffe, Anforderungen, Güteüberwachung This European Standard was approved by CEN on 1997-01-27. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comité Européen de Normalisation Europäisches Komitee für Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels © 1997 Copyright reserved to CEN members. Ref. No. EN 523:1997 E Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 02:02:53 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 523:1997 © BSI 04-2000 2 Foreword This European Standard has been prepared by Technical Committee CEN/TC 104, Concrete (performance, production, placing and compliance criteria), the Secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 1997, and conflicting national standards shall be withdrawn at the latest by September 1997. This European Standard applies together with the standards of the EN 524 series which comprises test methods for sheaths. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Contents Page Foreword2 1Scope3 2Normative references3 3Definitions3 4Classification3 5Requirements3 6Marking, technical documents, delivery note5 7Storage6 8Quality control procedures6 Annex A (informative) Explanatory notes9 Figure 1 Dimensions of couplers6 Table 1 Minimum requirements4 Table 2 Routine checks as specified in clause 8.2.3 and 8.2.47 Table 3 Testing of characteristics as specified in clause 58 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 02:02:53 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 523:1997 © BSI 04-20003 1 Scope This standard is applicable to uncoated cylindrical steel sheaths with a corrugated profile and with a nominal internal diameter of up to 130 mm1) and their connectors (couplers) which are assembled to form ducts for prestressing tendons in post-tensioned prestressed concrete elements. It is only applicable to sheaths and connectors made of interlocked or welded steel strip2)3). The seals required between sheaths and couplers are not covered by this standard4). 2 Normative references This European Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN 524-1, Steel strip sheaths for prestressing tendons Methods of test Part 1: Determination of shape and dimensions. EN 524-2, Steel strip sheaths for prestressing tendons Methods of test Part 2: Determination of flexural behaviour. EN 524-3, Steel strip sheaths for prestressing tendons Methods of test Part 3: To-and-fro bending test. EN 524-4, Steel strip sheaths for prestressing tendons Methods of test Part 4: Determination of lateral load resistance. EN 524-5, Steel strip sheaths for prestressing tendons Methods of test Part 5: Determination of tensile load resistance. EN 524-6, Steel strip sheaths for prestressing tendons Methods of test Part 6: Determination of leaktightness (Determination of water loss). ISO 6932, Cold-reduced carbon steel strip with a maximum carbon content of 0,25 %. 3 Definitions 3.1 types of sheath sheaths are designated by the manufacturer according to type, each type having certain features, e.g. production procedure (welded or interlocked), shape of profile, etc 3.2 connectors (couplers) connectors are specific devices to join sheath sections. They are usually made from cut ends of sheaths with the same profile type but with larger diameter (see 5.2) 3.3 stiffeners stiffeners are additional components whose purpose is to increase the lateral load strength of the sheaths at supporting points, e.g. semi-circular sheathing sections placed between supports and tendons 4 Classification Sheaths are classified by the requirements as given in Table 1. Class 1 (normal sheaths) Class 2 (rigid sheaths) 5 Requirements 5.1 Sheaths 5.1.1 General requirements Sheaths shall have sufficient strength to ensure that they are able to withstand varying degrees and types of mechanical loading. Sheaths shall have a corrugated profile to provide a sufficient mechanical bond with the concrete externally and the grout internally. The inner and outer surfaces of the sheaths shall be free of any detrimental corrosion (see clause 7). Sheaths shall be leaktight (see 5.1.9). All joints between sheaths shall be sealed carefully (see Annex A). The sheaths and their connectors shall be designed in such a way to allow this proper sealing of the joints. 1) For diameters greater than 130 mm requirements should be drawn up on the basis of this standard and agreed upon by the parties involved. 2) In case of coated or galvanized steel additional provisions have to be considered, which are not covered by this standard. 3) For plastic sheaths, see Annex A. 4) The appropriate rules will be specified in a separate European Standard for concrete structures which is under preparation. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 02:02:53 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 523:1997 4 © BSI 04-2000 5.1.2 Steel strip Sheaths shall be made from rolled steel strip conforming to ISO 6932 or specifies steel with similar properties. The nominal thickness of the steel strip shall be not less than the values given in Table 1, lines 1a and 1b. 5.1.3 Tolerances (ovality) Deviations from the mean values of the internal diameter of any cross-section of the sheaths determined according to EN 524-1 shall not exceed ± 1 % or ± 0,5 mm, whichever is the greater. 5.1.4 Relative volume of the profile The relative volume of the profile Vrel determined in accordance with EN 524-1 shall be not less than 0,08 cm3/cm2. For nominal internal diameters greater than 25 mm, the height of the profile shall be not less than 2,5 mm (see EN 524-1). 5.1.5 Flexural behaviour The relative load Frel = Fpl/d1 in N/mm and the load Fpl at the beginning of plastic deformation shall be determined in accordance with EN 524-2. The relative load Frel for class 2 shall not be less than the given values in Table 1, line 2. For class 1 there are no requirements but test results shall be given for information to the user in the relevant documents (see 6.2). 5.1.6 Flexibility When tested by means of the to-and-fro bending test described in EN 524-3, flexibility is sufficient if, after the bending test, no significant deformations of the corrugation appear so that the plunger can push in the specimen in whole length. A straightening of the specimen by means of the tensile load test (see EN 524-5) is permitted. 5.1.7 Lateral load resistance The irreversible reduction of the internal diameter shall not exceed 10 % or 5 mm whichever is the smaller when the loads given in Table 1, lines 4a to 4c are applied according to EN 524-4. If any type of sheaths of class 1 withstands the load Fl = 1 500 N without a stiffener a test with lower forces accordance to Table 1, line 4a is not required. 5.1.8 Tensile load resistance When loaded in accordance with EN 524-5, the tensile load strength is sufficient if the sleeve coupling (comprising sheaths and the corresponding coupler) does not fall by complete separation under the test loads specified in Table 1, line 5. 5.1.9 Leaktightness When tested in accordance with EN 524-6, using a specimen tested earlier for flexibility, lateral load resistance and tensile load resistance, the water loss shall not exceed the values given in Table 1, line 6. Table 1 Minimum requirements 1234567891011 CharacteristicClass Nominal internal diameter d1 in mm k 25 over 25 to 35 over 35 to 45 over 45 to 55 over 55 to 65 over 65 to 75 over 75 to 85 over 85 to 100 over 100 to 130 1a Nominal thickness of steel strip in mm 10,200,250,250,300,300,350,350,40U 0,40 1b20,400,450,450,500,500,60U 0,60 2Relative load Fpl/d1 in N/mm 23,03,54,04,04,55,05,56,06,5 3a Radius r for the flexibility test, in mm (maximum values) 17507507507507507507509001 000 3b21 500 1 5001 5001 5001 5001 5001 5001 8001 800 4a Lateral load Fl in N without stiffeners 15006007507509509509501 0501 050 4bwith stiffeners 11 500 1 5001 5001 5001 5001 5001 5001 5001 500 4cwithout stiffeners 21 500 1 5001 5001 5001 5001 5001 5001 5001 500 5Tensile load F2 in N 1 and 2 2504006009001 1001 4001 6001 9002 200 6Tightness1 and 2 Water loss k 1,5 % by volume Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 02:02:53 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 523:1997 © BSI 04-20005 5.2 Connectors (couplers) 5.2.1 General requirements Couplers made from corrugated metal strip sheaths shall fulfil the requirements given in 5.1.1. 5.2.2 Minimum length The length of the couplers shall be at least three times the nominal internal diameter of the sheaths, but not less than 150 mm. 5.2.3 Nominal internal diameter and wall thickness of the couplers When measured in accordance with EN 524-1, the nominal internal diameter of the couplers d1,c shall not exceed a value of d1,c = d1,s + 8ts + c (for interlocked sheaths) d1,c = d1,s + 3ts + c (for welded sheaths) where (see also Figure 1) The clearance, c, shall not exceed 2,0 mm for sheaths with an internal diameter of up to 55 mm or 3,0 mm for larger diameters. The steel strips from which couplers are made shall at least fulfil the minimum requirements concerning the wall thickness as the sheaths which are to be connected (see Table 1, lines 1a to 1b). 5.3 Stiffeners It shall be possible to strengthen locally those sheaths which do not possess the increased lateral load resistance specified in Table 1, line 4b. The size of the stiffeners shall not exceed half the circumference of the sheath and shall be designed such that, after concreting, no cavities remain between the sheath and the stiffener which could have detrimental effects. This requirement can be met for instance by using the same profile and at least the same wall thickness for stiffener and sheath. The length of the stiffeners shall not exceed 1,5 times the nominal internal diameter of the sheaths or 10 cm, whichever is the greater. 6 Marking, technical documents, delivery note 6.1 Marking The producers mark or trademark, the reference “EN 523”, classification, nominal internal diameter and, where necessary, the type of sheath shall be displayed either on each packing unit or transport bundle or on the sheaths themselves. 6.2 Technical docu