1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 12504-2:2012Testing concrete in structuresPart 2: Non-destructive testing Determination of rebound numberCopyright European Committee for Standardization Provided by IHS un
2、der license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12504-2:2012 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 12504-2:2012. It supersedes BS EN 12504-2:2001 which is withdrawn.The UK participation in it
3、s preparation was entrusted to Technical Committee B/517/1, Concrete production and testing.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible
4、 for its correct application. The British Standards Institution 2012. Published by BSI Standards Limited 2012ISBN 978 0 580 76921 4 ICS 91.100.30 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards
5、Policy and Strategy Committee on 31 January 2013.Amendments issued since publicationDate Text affectedCopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12504-2:2012EUROPEAN S
6、TANDARD NORME EUROPENNE EUROPISCHE NORM EN 12504-2 September 2012 ICS 91.100.30 Supersedes EN 12504-2:2001English Version Testing concrete in structures - Part 2: Non-destructive testing -Determination of rebound number Essais pour bton dans les structures - Partie 2: Essais non destructifs - Dtermi
7、nation de lindice de rebondissement Prfung von Beton in Bauwerken - Teil 2: Zerstrungsfreie Prfung - Bestimmung der Rckprallzahl This European Standard was approved by CEN on 13 July 2012. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for gi
8、ving 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 CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three of
9、ficial 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 CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies
10、of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain
11、, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN nati
12、onal Members. Ref. No. EN 12504-2:2012: ECopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12504-2:2012EN 12504-2:2012 (E) 2 Contents Page Foreword 31 Scope 42 Normative refe
13、rences 43 Principle 44 Apparatus .44.1 Rebound hammer 44.2 Reference anvil 44.3 Abrasive stone .55 Test location .55.1 Selection .55.2 Preparation .56 Procedure .56.1 Preliminary preparation 56.2 Operations 56.3 Reference checking .67 Test result .68 Test report 69 Precision .7Bibliography 8National
14、 Annex NA (informative) Guidance on the application of surface hardness testing by rebound hammer 9Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12504-2:2012EN 12504-2:20
15、12 (E) 3 Foreword This document (EN 12504-2:2012) has been prepared by Technical Committee CEN/TC 104 “Concrete and related products”, 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 en
16、dorsement, at the latest by March 2013, and conflicting national standards shall be withdrawn at the latest by March 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identi
17、fying any or all such patent rights. This document supersedes EN 12504-2:2001. This document is based on the International Standard ISO 1920-7, Testing of concrete Part 7: Non-destructive tests on hardened concrete, and reference has been made to ASTM C805, Standard Test Method for Rebound number of
18、 hardened concrete. This document has been framed around the use of a Type N, spring driven steel hammer, originally designed by Schmidt. This European Standard is one of a series of test methods for concrete. The series EN 12504 “Testing concrete in structures“ consists of the following parts: Part
19、 1: Cored specimens Taking, examining and testing in compression; Part 2: Non-destructive testing Determination of rebound number; Part 3: Determination of pull-out force; Part 4: Determination of ultrasonic pulse velocity. The main changes with respect to the previous edition are listed below: a) e
20、ditorial revision; b) clarification to the procedure for carrying out the test and indicates the required specification of the equipment to be used; c) the option of using an electronic measuring device as well as the mechanical version. According to the CEN/CENELEC Internal Regulations, the nationa
21、l standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithua
22、nia, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without
23、license from IHS-,-,-BS EN 12504-2:2012EN 12504-2:2012 (E) 4 1 Scope This European Standard specifies a method for determining the rebound number of an area of hardened concrete using a spring-driven hammer. NOTE 1 The rebound number determined by this method can be used to assess the uniformity of
24、concrete in situ, to delineate zones or areas of poor quality or deteriorated concrete in structures. NOTE 2 The test method is not intended as an alternative for the compressive strength determination of concrete (EN 12390-3), but with suitable correlation, it can provide an estimate of in situ com
25、pressive strength. For the assessment of in-situ compressive strength see EN 13791. NOTE 3 The hammer may be used for comparative testing, referenced against a concrete with known strength or against a concrete which has been shown that it has come from a defined volume of concrete with a population
26、 verified as conforming to a particular strength class. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest
27、 edition of the referenced document (including any amendments) applies. EN ISO 6508-1, Metallic materials Rockwell hardness test Part 1: Test method (scales A, B, C, D, E, F, G, H, K, N, T) (ISO 6508-1) 3 Principle A mass propelled by a spring strikes a plunger in contact with the surface of the str
28、ucture or specimen to be tested. The test result is expressed as a number in terms of the rebound distance of the mass. A number may also be obtained in terms of the energy or velocity differential before and after impact of the mass. 4 Apparatus 4.1 Rebound hammer Consisting of a spring-loaded hamm
29、er mass which, when released, strikes a plunger in contact with the surface to be tested. The rebound distance of the hammer mass from the plunger or other rebound values shall be measured. NOTE Several types and sizes of rebound hammers are commercially available for testing various strength classe
30、s and types of concrete. Each type and size of hammer should be used only with the strength class and type of concrete for which it is intended. 4.2 Reference anvil Steel reference anvil for verification of the hammer, with an impact area having a hardness of minimum 52 HRC when tested in accordance
31、 with EN ISO 6508-1 and a mass of (16 1) kg and a diameter of approximately 150 mm. Other anvils may be used if it can be demonstrated the accuracy of the readings are not significantly affected. The manufacturers instructions and any other equipment shall be used to ensure the longitudinal axis of
32、the plunger is perpendicular to the surface of the anvil at impact. NOTE Verification on an anvil will not guarantee that different hammers will yield the same results at other points on the rebound scale. Copyright European Committee for Standardization Provided by IHS under license with CENNot for
33、 ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12504-2:2012EN 12504-2:2012 (E) 5 4.3 Abrasive stone A medium-grain texture silicon carbide stone or equivalent material. 5 Test location 5.1 Selection Concrete elements to be tested shall be at least 100 mm thick and
34、fixed within a structure. Smaller elements or specimens may be tested provided they are rigidly supported. Areas exhibiting honeycombing, scaling, rough texture, or high porosity should be avoided. In selecting an area to be tested, the following factors should be considered: a) the strength of the
35、concrete; b) type of surface (e.g. formed or unformed); c) type of concrete (e.g. normal or lightweight); d) moisture condition of the surface; e) carbonation (if appropriate); f) direction of test; g) other appropriate factors. A test location should be approximately 300 mm 300 mm. 5.2 Preparation
36、Using the abrasive stone, grind heavily textured or soft surfaces, or surfaces with loose mortar, until they are smooth and free of loose material. Smooth-formed or trowelled surfaces may be tested without grinding. Remove any water present on the surface of the concrete. 6 Procedure 6.1 Preliminary
37、 preparation 6.1.1 Use the hammer in accordance with the manufacturers instructions for its operation. 6.1.2 Before a sequence of tests on a concrete surface, clean the impact surfaces of the reference anvil and plunger. Perform at least five impacts on the steel reference anvil and record the readi
38、ngs from the next five impacts. If the readings from the last five impacts are not within 3 of the value given by the manufacturer, clean and/or adjust the hammer in accordance with the manufacturers instructions and repeat the above. 6.1.3 The hammer shall only be operated at a temperature within t
39、he range 0 C to 50 C. 6.2 Operations At the time of the test, the hammer shall meet the requirements defined in 6.1.2. Hold the hammer firmly in a position that allows the plunger to impact perpendicularly to the surface being tested. Copyright European Committee for Standardization Provided by IHS
40、under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12504-2:2012EN 12504-2:2012 (E) 6 Gradually increase the pressure on the plunger until the hammer impacts (see 6.1.1). After impact, record the rebound number based on the rebound distance
41、and/or energy or velocity measurements. Examine each impression made on the surface after impact and if the impact has crushed or broken through a near-to-surface void, discount the result. Take a minimum of nine valid readings to obtain a reliable estimate of the rebound number for a test location.
42、 Record the position and orientation of the hammer for each set of readings. Ensure that no two impact points are closer than 25 mm and none are within 25 mm of an edge. NOTE It is preferable to draw a regular grid of lines 25 mm to 50 mm apart and take the intersections of the lines as the test poi
43、nts. 6.3 Reference checking After performing the tests, take five readings using the steel reference anvil. If the readings are not within 3 of the value given by the manufacturer, clean and/or adjust the hammer according to the manufacturers instruction and repeat the test. 7 Test result The reboun
44、d number of the test location shall be taken as the median of all the readings, adjusted if necessary to take into account the orientation of the hammer in accordance with the manufacturers instructions. The rebound number shall be expressed as a whole number. If more than 20 % of all the readings d
45、iffer from the median by more than 30 % the entire set of readings shall be discarded. NOTE If more than one hammer is to be used, a sufficient number of tests should be made on similar concrete surfaces with all hammers, to determine the variation in the results obtained. 8 Test report The report s
46、hall include: a) identification of the concrete structure/element; b) identification of test location(s); c) identification of the rebound hammer and its specification if known; d) description of preparation of test location(s); e) details of concrete (if known) and its condition; f) date/time of pe
47、rformance of the test; g) rebound number (median of test result readings) adjusted for hammer orientation (if appropriate) for each test location; h) any deviation from the standard test method e.g. presence of water on surface (see 5.2), temperature outside acceptable range (see 6.1.3); Copyright E
48、uropean Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12504-2:2012EN 12504-2:2012 (E) 7 i) a declaration by the person technically responsible for the test that it was carried out in accordance with this document, except as noted in item h). The report may include: j) individual rebound hammer readings, if required. 9 Precision There are no precision data available for this test. Copyright European Committee for Standardization Provided by IHS under license with
