ISO INTERNATIONAL STANDARD 6934-1 First edition 1991-07-01 Steel for the prestressing of concrete Part 1: General requirements Acierpourarmatures deprecontrainte Partie1:Specifications generales Referencenumber ISO 6934-1:1991(E) ISO 6934-1:1991(E) Foreword iso (the International Organization for Standardization)is a worldwide federationof national standardsbodies (iso memberbodies).The work of preparing International Standards isnormally carriedout through Iso technical committees.Each member body interested in a subject for which a technical committee has been established has the rightto be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with IsO, also take part in the work.Iso collaborates closely with the Internationai Electrotechnical Commission (iEC)onallmattersofelectrotechnicalstandardization Draft International Standards adopted by thetechnical committees are circulated to the member bodies for voting. Publication as an Inter- national Standard requires approval by at least75%of the member bodies casting a vote. International StandardIso6934-1waspreparedbyTechnicalCommittee ISO/TC17.Steel. iso6934consists of thefollowingparts,underthegeneral titleSteelfor theprestressing ofconcrete: --- Part 1:General requirements Part2:Cold-drawnwire --Part3:Quenchedandtemperedwire Part4:Strand Part5:Hot-rolled steelbarswithorwithout subsequentprocessing AnnexAformsanintegralpartofthispartofiso6934.AnnexesBand Careforinformationonly. ISO.1991 or by any means,electronic or mechanical, including photocopying and microfim, without permission inwritingfromthepublisher. InternationalOrganizationforStandardization CasePostale56.CH-1211Geneve20·Switzerland Printed in Switzeriand ii ISO 6934-1:1991(E) INTERNATIONAL STANDARD Steel for the prestressing of concrete Part 1: General requirements 3.1 cast analysis: Chemical analysis of a sample Scope 1 ofthe molten steel during casting. 1.1 Iso6934 specifiesrequirements for high 3.2, characteristic value: Value having a prescribed tensile strength steel to be used in prestressed probability of not being attained in a hypothetical concrete. it applies only to material in the condition unlimitedtest series.[isO8930] as supplied by the manufacturer.Itdoes not cover requirements for materials and anchorage devices NOTE 1 Equivalent to fractile, which is defined in used in conjunction with the prestressing steel in ISO3534. structural components. 3.3 nominalcross-sectional area:The cross- 1.2The specific properties for each type of pre- sectional area equivalent to the area of a circular stressing steel are given in Iso 6934-2 to iso 6934-5. plain bar of nominal diameter. 3.4 relaxation: Time-dependent stress loss for a Normative references constant length.Relaxation is stated as a percent- age of the initial stress applied to the steel. The following standards contain provisions which through reference in this text, constitute provisions of thispart of iso 6934.At thetime of publication Manufacturing process 4 the editions indicated were valid. Ail standards are subjecttorevision,andpartiestoagreementsbased Steel according to iso 6934 may be made by any on this partof iso6934are encouragedto investi- process except the air or mixed air/oxygen bottom gate the possibility of applying the most recent edi- blownprocesses. tions of the standards indicated below. Members of IEC and ISo maintain registers of currently valid International Standards. Types of prestressing steel 5 Iso1099:1975,Metals--Axial loadfatiguetesting 5.1Cold-drawn wire Iso6892:1984,Metallicmaterials-Tensiletesting. A solid product obtained from a rod by cold working through dies or rollers. The product is supplied in Iso7801:1984,Metallicmaterials-Wire-Reverse coils of diameter approximately equal to that of the bend test. wiredrawing machine capstan (millcoils)orin larger diameter coils of straightened wire. Iso10065:1990,Steelbarsfor reinforcement of con- crete -- Bend and