1、BS ISO 11528:2016Buildings and civil engineeringworks Sealants Determination of crazing andcracking following exposure toartificial or natural weatheringBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 11528:2016 BRITISH STANDARDNational forewordThis British St
2、andard is the UK implementation of ISO 11528:2016.The UK participation in its preparation was entrusted to Technical Committee B/547, Sealants for building and construction.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not pur
3、port to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 86013 3 ICS 91.100.50 Compliance with a British Standard cannot confer immunity from legal oblig
4、ations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 August 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 11528:2016 ISO 2016Buildings and civil engineering works Sealants Determination of crazing
5、and cracking following exposure to artificial or natural weatheringBtiments et ouvrages de gnie civil Mastics Dtermination du tressaillage et du craquelage suite une exposition au vieillissement naturel ou artificielINTERNATIONAL STANDARDISO11528First edition2016-08-01Reference numberISO 11528:2016(
6、E)BS ISO 11528:2016ISO 11528:2016(E)ii ISO 2016 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2016, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical
7、, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, Switzerla
8、ndTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 11528:2016ISO 11528:2016(E)Foreword iv1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 15 Apparatus . 26 Observer 27 Evaluation specimens 27.1 General . 27.2 Specimen thickness . 27.3 Size of inspec
9、tion surface. 27.4 Flatness of inspection surface 27.5 Conditioning of evaluation specimens . 28 Procedure. 38.1 Viewing of evaluation specimens 38.2 Assessment of test specimens prior to exposure 38.3 Weathering . 38.4 Assessment of test specimens after exposure . 38.5 Photo documentation of evalua
10、tion specimens . 59 Test report . 6Annex A (informative) Photographic documentation 8Annex B (informative) Preparation of the specimen for photography 14Bibliography .18 ISO 2016 All rights reserved iiiContents PageBS ISO 11528:2016ISO 11528:2016(E)ForewordISO (the International Organization for Sta
11、ndardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the righ
12、t to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures
13、used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rule
14、s of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identif
15、ied during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on
16、the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO
17、/TC 59, Building and civil engineering works, Subcommittee SC 8, Sealants.iv ISO 2016 All rights reservedBS ISO 11528:2016INTERNATIONAL STANDARD ISO 11528:2016(E)Buildings and civil engineering works Sealants Determination of crazing and cracking following exposure to artificial or natural weatherin
18、g1 ScopeThis International Standard specifies methods for the assessment of surface defects (crazing and cracking) on sealants after exposure to artificial or natural weathering.NOTE Sealants are weathered in the laboratory in order to simulate ageing processes occurring during natural weathering. G
19、enerally, valid correlations between ageing during artificial and natural weathering cannot be expected because of the large number of influencing factors. Certain relationships can only be expected if the effect of the important parameters (spectral distribution of the irradiance in their photochem
20、ically relevant range, temperature of the specimen, type of wetting, wetting cycle relative humidity) on the sealant is known. However, unlike natural weathering, testing in the laboratory is carried out taking into consideration a limited number of variables which can be controlled, and therefore,
21、the results are more reproducible.2 Normative referencesThe 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 edition of the referen
22、ced document (including any amendments) applies.ISO 291, Plastics Standard atmospheres for conditioning and testingISO 3668, Paints and varnishes Visual comparison of the colour of paintsISO 6927, Buildings and civil engineering works Sealants VocabularyCIE Publication No.51, A Method for Assessing
23、the Quality of Daylight Simulators for Colorimetry (CIE 051.2-1999 (including Supplement 1-1999)3 Terms and definitionsFor the purposes of this document, the definitions given in ISO 6927 apply.4 PrincipleThis International Standard defines an evaluation scheme for designating the quantity and quali
24、ty of specific surface defects (cohesive cracks and crazes) occurring in sealants as a result of exposure to outdoor or artificial weathering. The sealant test specimens are visually examined and rated for crack density, crack width, and crack depth. The extent of damage in terms of crack width and
25、crack density is determined by visual evaluation and comparison with pictorial references provided in this International Standard. The crack depth is visually assessed with reference to a rating scale.Visual assessment is carried out under specified illumination and viewing conditions in artificial
26、daylight (D65). Findings are documented by digital photography. ISO 2016 All rights reserved 1BS ISO 11528:2016ISO 11528:2016(E)5 Apparatus5.1 Standardized lighting apparatus, in accordance with ISO 3668, which is illuminating the test specimen surface with artificial daylight (D65) 6 500 K.The qual
27、ity of simulation of daylight shall be assessed by the method described in CIE Publication No. 51. The spectral distribution of the illuminant shall be in category BC (CIELAB) or better. The level of illumination at the specimen inspection position shall be between 2 000 lx and 4 000 lx.5.2 Calliper
28、 gauge, with an accuracy of 0,05 mm, for the measurement of deviation of specimen surface flatness.5.3 Microscope, with a magnification of 10, for the assessment of surface defects.6 ObserverObservers shall have normal colour vision and shall be selected carefully because a significant proportion of
29、 people have defective colour vision. To avoid eye fatigue effects, pastel or complementary colours shall not be viewed immediately after strong colours. The quality of visual judgements falls off severely if the observer works continuously. Rest periods of several minutes, during which no specimen
30、inspection is attempted, shall therefore be taken frequently.7 Evaluation specimens7.1 GeneralEvaluation specimens are cured sealant samples with or without adjacent substrates (supports) that have been exposed to either natural (outdoor) or artificial weathering. A minimum of two specimens shall be
31、 evaluated for each sealant product and weathering condition.7.2 Specimen thicknessThe thickness of the evaluation specimen (cured sealant layer) shall be a minimum of 3 mm.7.3 Size of inspection surfaceThe size of the specimen surface that is inspected for surface defects shall be at a minimum 10 m
32、m 20 mm and at a maximum 40 mm 50 mm in size.NOTE Standard-sized test specimens according to ISO 8339 are deemed as providing a suitable inspection surface.7.4 Flatness of inspection surfaceThe inspection surface of the evaluation specimens shall be nearly flat, i.e. the deviation of the inspection
33、surface from a perfect plane shall not exceed 2 mm at any point across the inspection surface. Deviation from the plane is measured by placing a straight-edge steel ruler across the specimen and using a standard pointed depth gauge (calliper gauge, 5.2). The measured value shall be expressed as conc
34、ave (+) when the surface layer is facing towards the ruler and as convex () when the surface layer is facing away from the ruler.7.5 Conditioning of evaluation specimensThe evaluation specimens shall be conditioned at (23 2) C and (50 10) % relative humidity (standard atmosphere 23/50 class 2 accord
35、ing to ISO 291) for a minimum of 16 h prior to inspection.2 ISO 2016 All rights reservedBS ISO 11528:2016ISO 11528:2016(E)8 Procedure8.1 Viewing of evaluation specimensView the evaluation specimens at a distance of 30 cm to 40 cm and an angle of 45 to 60 with illumination at an angle of 90 or vice v
36、ersa in a controlled lighting apparatus (5.1) under standardized lighting conditions conforming to CIE standard illuminant artificial daylight (D65) 6500 K.8.2 Assessment of test specimens prior to exposureIf evaluation specimens are not obtained from the field and therefore are available prior to e
37、xposure, each specimen shall be inspected. Specimens with any significant application defects (bubbles, deviations from planarity, etc.) shall be discarded.8.3 WeatheringThe evaluation specimens shall be exposed to natural (outdoor) or artificial weathering.NOTE Weathering can be carried out with or
38、 without simultaneous or sequential cyclic movement. For a discussion of different weathering methods see, for instance, ISO 11617 or the RILEM Technical Recommendations.2348.4 Assessment of test specimens after exposureAfter exposure to natural (outdoor) or artificial weathering, the evaluation spe
39、cimens are inspected visually under controlled lighting conditions (see 8.1). Inspection of the evaluation specimens may occur in their non-extended state or, preferably, in an extended state. The extension amplitude applied during inspection of the evaluation specimens shall be reported in the test
40、 report (extension amplitude of non-extended specimens: 0 %).The specimens shall be examined for evidence of loss of adhesion and cohesion or any surface changes (cracking, crazing, chalking, etc.) of the sealant beads. Certain types of degradation that are only visible at the back surface may occur
41、. Report any relevant observation, such as splitting of the sealant surface, depolymerization (reversion) of the bulk sealant, etc.Determine the rating for quantity, width, and depth of cohesive cracks over the inspection area according to Table 1, Table 2, and Table 3, respectively. Assess the quan
42、tity of cohesive cracks by reference to Table 1 and by using, as an example, Figure 1 a) and Figure 1 b), depending on the type of cracking. The degree of degradation (crack width, crack density, and crack depth) can vary over the specimen surface. In such cases, the determination of the crack width
43、, crack density, and crack depth shall be made at several locations on the specimen surface and the minimum and maximum value shall be reported.NOTE 1 Figure 1 a) shows cracking without preferential direction and Figure 1 b) shows cracking in one preferential direction. Other forms of cracking occur
44、, but the principles of assessing the quantity remain the same (see Annex A).Use measuring devices capable of reading to 0,05 mm for crack depth and width.NOTE 2 Various tools for the determination of crack depth, which are often used in the study of corrosion-induced pitting and cracking, for examp
45、le, measuring microscope, digital optical micrometer, and digital pit and crack depth gauges are commercially available.If required for the proper rating of surface defects of outdoor weathered specimens, remove surface contamination by detergent wash followed by water rinse. No aggressive solvents
46、should be used. Brushing or wiping of the surface may damage the surface topology and should be avoided. Ultrasonically aided cleaning is often particularly effective in achieving satisfactory surface decontamination. ISO 2016 All rights reserved 3BS ISO 11528:2016ISO 11528:2016(E)For specimens expo
47、sed to natural (outdoor) weathering, dirt deposited on the surface from the atmosphere or surface mould growth may mask some of the cracking and crazing. In this case, efforts shall be made to remove the dirt or mould by suitable means.Table 1 Rating for quantity of cohesive cracksRating Quantity of
48、 cracks (Q)0 None, i.e. no detected cracks1 Very few, i.e. some just detectable cracks2 Few, i.e. small number of cracks3 Moderate, i.e. medium number of cracks4 Considerable, i.e. significant number of cracks5 Dense, i.e. dense pattern of crackingTable 2 Rating for width of cohesive cracksRating Wi
49、dth of cracks0 Not visible at 10 magnification1 Only visible under magnification up to 102 Just visible with normal (or corrected) vision (1 mm to 3 mm depth)4 Very significant surface crack depth (3 mm to 10 mm depth)5 Cohesive failure (10 mm depth)4 ISO 2016 All rights reservedBS ISO 11528:2016ISO 11528:2016(E)Q = 1 Q = 2 Q = 3 Q = 4 Q = 5a) Cracking without preferential directionb) Cracking in one preferential directionFigure 1 Examples for assessing the quantity of cohesive cracksFigure 1 a)
