1、Designation: C1394 03 (Reapproved 2012)Standard Guide forIn-Situ Structural Silicone Glazing Evaluation1This standard is issued under the fixed designation C1394; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONSSG is popular because of its unique method of retaining glass or other panels in smooth exteriorwalls, interrupted only by na
3、rrow sealant joints. The first four-sided SSG in commercial constructionis on the former corporate headquarters building of SHG Incorporated (formerly known as Smith,Hinchman unknown structuralsealant durability; and the level of understanding of the principles of SSG by glazers. This guideaddresses
4、 these concerns by providing suggestions for in situ evaluations of completed installations ofany age.1. Scope1.1 It is recommended to periodically evaluate the existingcondition of structural sealant glazing (hereinafter called SSG)installations in situ to detect problems before they becomesevere o
5、r pervasive. Evaluation of existing SSG installationsare required by certain building codes and local ordinances.This guide provides a program to evaluate the existingconditions, lists typical conditions, which might be found, andsuggests times when such evaluations are appropriate. Thecommittee wit
6、h jurisdiction over this standard is not aware ofany comparable standards published by any other organiza-tions.2. Referenced Documents2.1 ASTM Standards:2C717 Terminology of Building Seals and SealantsC1392 Guide for Evaluating Failure of Structural SealantGlazingC1401 Guide for Structural Sealant
7、Glazing3. Terminology3.1 Definitions:The definitions of the following terms usedin this guide are found in Terminology C717: structural sealant;structural sealant glazing; two-sided structural sealant glazing;four-sided structural sealant glazing; fluid migration.3.2 Definitions of Terms Specific to
8、 This Standard:3.2.1 qualified personone with a recognized degree orprofessional registration and extensive knowledge and experi-ence in the field of structural sealant glazing, and who iscapable of design, analysis, evaluation, and specifications inthe subject.4. Significance and Use4.1 Guidelines
9、are provided for the procedures to evaluateexisting SSG installations, including two- and four-sidedinstallations. Due to the unlimited range of materials that maybe used in a particular building, the information contained inthis guide is general in nature. For a discussion of new SSGinstallations,
10、refer to Guide C1401.4.2 Typical conditions are listed that might be discoveredduring, or suggest the need for, such evaluations. Guidelinesare also suggested for times to perform evaluations. Theseguidelines are also necessarily general. Professional judgmentof a qualified person should be used in
11、determining theappropriate time to perform an evaluation on a particularbuilding.4.3 This guide should not be the only reference consultedwhen determining the scope of a proposed evaluation. Forexample, the local building code and the manufacturers1This guide is under the jurisdiction ofASTM Committ
12、ee C24 on Building Sealsand Sealants and is the direct responsibility of Subcommittee C24.10 onSpecifications, Guides and Practices.Current edition approved Dec. 1, 2012. Published December 2012. Originallyapproved in 1998. Last previous edition approved in 2008 as C139403(2008). DOI:10.1520/C1394-0
13、3R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO
14、Box C700, West Conshohocken, PA 19428-2959. United States1product literature for the actual materials used (if known)should also be considered.4.4 This document is not a substitute for experience andjudgment in assessing the condition of the specialized types ofconstruction discussed.5. Reasons to P
15、erform an Evaluation5.1 There are numerous reasons that a building owner ormanager (hereinafter “owner”) may choose to evaluate an SSGsystem, whether discretionary or to comply with an ordinance.The recommended evaluation levels, as discussed in Section 7,are referenced for each situation. The findi
16、ngs from one levelof investigation may trigger the need for a more in-depthinvestigation. At a minimum, it is recommended that anexisting SSG installation be evaluated when triggered by anyof the following events:5.1.1 After a natural disaster, such as an earthquake or majorwind storm, or a man-made
17、 disaster such as a bomb blast,Level 2;5.1.2 After a recall or published concern over a specificproduct or system, Level 1;5.1.3 Upon a change of property ownership, Level 1;5.1.4 Before repeating a new design, Level 1;5.1.5 As dictated by government regulations, Level 1 or 2;or5.1.6 When distress i
18、s discovered (see Section 8), Level 2,or, if prevalent distress is found, Level 3.5.2 In addition to event-triggered evaluations, it is recom-mended that proactive owners also perform periodic evalua-tions at the following intervals: (Note that some of theseperiods may overlap. If distress is found
19、during any evaluation,then more frequent and more in-depth evaluations should beconsidered.)5.2.1 When convenient, such as in conjunction with occa-sional glass replacement, or when access is available, Level 1;5.2.2 Immediately after installation of a new system, Level2;5.2.3 Just before expiration
20、 of the warranty period, Level 2;5.2.4 Between 1 and 2 years after substantial completion,Level 1;5.2.5 After 5 years, Level 1;5.2.6 After 10 years, Level 2;5.2.7 After 15 years, Level 1 (if Level 2 was performed asrecommended after 10 years); and5.2.8 After 20 years, and each successive 10 years, L
21、evel 2.6. Symptoms of Problems With SSG6.1 Whether due to original construction mistakes or latentdefects, SSG installations sometimes exhibit distress. Thefollowing list summarizes conditions that may indicate poororiginal construction or a subsequent failure of the structuralsealant, and therefore
22、 require evaluation. This list may not beall-inconclusive.6.1.1 Glass breakage from an unknown causeThere arenumerous potential causes of spontaneous glass breakage; ifthe cause is unknown, then it should be investigated prior toglass replacement whether an SSG defect contributed to thefailure.6.1.2
23、 Air or water infiltrationIf air or water migratesthrough or to the structural sealant joint, then it must also havelost its structural functionat least for part of its length.Symptoms of air or water leakage include:6.1.2.1 Visible accumulation of liquid water during orfollowing storms;6.1.2.2 Wet
24、insulation;6.1.2.3 Organic growth;6.1.2.4 Water stains or salt deposits;6.1.2.5 Audible rattle or whistle;6.1.2.6 Discoloration of laminated glazing;6.1.2.7 Condensation or frost on glazing;6.1.2.8 Fogging of insulated glass units;6.1.2.9 Opacifier failure on spandrel glassMoisture is afactor in the
25、 failure of some opacifiers, and may indicate waterinfiltration; and6.1.2.10 Visible sealant failures Sealant failures may beobserved from inside or outside, depending on the design, andmay involve the weather-seal joint as well as the structuraljoint. Visible manifestations of sealant failures incl
26、ude:6.1.2.10.1 Intermittent loss of adhesionNonadhered sealant may differ in iridescence or reflectivitycompared to adhered sealant when viewed through the glass;6.1.2.10.2 Fluid migration or exudationThe accumulation of a fluid residue on the sealant or glass mayindicate a chemical reaction between
27、 the sealant and anincompatible adjacent material;6.1.2.10.3 Discoloration of the sealantA color change may indicate a chemical reaction between thesealant and an incompatible adjacent material;6.1.2.10.4 Cohesive failureAlthough difficult to observe from inside or outside, cohesivefailure could ind
28、icate overstressing of the sealant;6.1.2.11 Disengaged or nonaligned lites, or displaced spac-ers or setting blocks, which may indicate glass displacement;and6.1.2.12 Poor dimensional control of a structural sealantjointWhen viewed from inside or outside, the structuralsealant should have uniform di
29、mensions and full joints. Vary-ing dimensions may indicate poor original installationpractices, or improper/inadequate cure of the sealant.7. Procedures for Evaluating Existing Conditions7.1 The following evaluation procedures are recommendedto be performed in determining the condition of an SSGinst
30、allation. Depending on the reason for the evaluation and thetype of installation, only certain procedures may be necessary;for example, more scrutiny is warranted for high-rise, 4-sidedSSG than for low-rise, 2-sided SSG. The objective of theevaluation is to obtain a reasonable degree of confidence i
31、n theexisting system, since one hundred percent certainty is notpossible.7.2 Different levels of expertise are needed to perform thevarious levels of evaluation, but in all cases a qualified personshould supervise the evaluation.7.3 Level 1Perform all of the following evaluation proce-dures:C1394 03
32、 (2012)27.3.1 Review project documentation, including original de-sign drawings, shop drawings, mock-up testing report, andprevious evaluation reports. Review original SSG designcalculations, or if not available, perform calculations to deter-mine stress on sealant from thermal and wind loading (and
33、,where appropriate, seismic loading);7.3.2 Interview building management and maintenance per-sonnel and tenants regarding breakage history of lites and otherdistress. Map findings on elevation drawings, and assesswhether a pattern exists; and7.3.3 Perform a cursory visual assessment from the interio
34、r,and from the exterior ground, roofs, and balconies.7.4 Level 2Perform the following, plus all of the proce-dures of Level 1 (unless a Level 1 evaluation has beenperformed previously and the documentation recommended tobe kept by the owner in 8.2 is available):7.4.1 Perform close-up visual evaluati
35、on from the interior;7.4.2 Observe weatherseal joints and structural joints fromthe exterior. Document distress, and assess whether a patternexists. Utilize high-powered optical tools to assist in observingfrom remote viewing areas, or from suspended scaffolding.Choose scaffold “drops” to represent
36、the entire building,including different wind zones, elevations, exposures, details,and construction times; and7.4.3 Qualitatively measure the sealant adhesion by press-ing in with a thumb. Alternatively, semi-quantitative adhesionstrength data can be obtained using a Chatalon spring loadindicator, o
37、r pulling cut tabs to failure and measuring theelongation.7.5 Level 3Perform all of the following procedures underthe field supervision of a qualified person, plus the proceduresof Levels 1 and 2 (except that Level 1 may be eliminated if ithas been performed previously and the documentation recom-me
38、nded to be kept by the owner in 8.2 is available:7.5.1 Consider whether the existing conditions indicate thatevaluation of all lites is warranted. If not, develop a rationalapproach for evaluating a representative sample of the totallites. There is a trade-off between accuracy and the cost of thestu
39、dy. For quantitative tests and measurements, it is recom-mended that the number of specimens or tests be selected toensure achieving at least a 90 % confidence interval with amaximum 20 % margin of error. Different levels of study mayrequire stricter parameters; and7.5.2 Perform in-situ load testing
40、 on selected lites, either byuniform load (air pressure) or point load (suction cups). Oneapplicable test method is described in Guide C1392.8. Report and Record Keeping8.1 At the conclusion of the evaluation, a written reportshould be prepared presenting findings, conclusions, and, ifappropriate, r
41、ecommendations for remedial action.8.2 It is very important that the evaluation data be main-tained by the building owner in a standardized format tofacilitate comparisons over time. It is recommended that allevaluation reports be kept in one notebook binder, along withother information pertinent to
42、 the SSG installation.8.3 The report should provide the following information:8.3.1 Building identification, background information, andreferences to original design and construction firms.8.3.2 Purpose of evaluation, and triggering event or reason.8.3.3 Evaluation procedures used, including referen
43、cing thespecified levels of evaluation in this guide.8.3.4 Availability and adequacy of original design andconstruction documentation, drawings, and calculations, espe-cially in relation to current code requirements or state-of-the-art SSG design procedures.8.3.5 Distress and defects observed.8.3.6
44、Changes since last evaluation.8.3.7 Field testing results. Record findings and test locationson elevation drawings in an appendix.8.3.8 Expected reliability of extrapolating the findings fromlimited areas to the entire system.8.3.9 Recommendations for further evaluation or remedialaction.9. Keywords
45、9.1 distress; durability; glazing; structural glazing; struc-trual sealant glazing; structural sealant joint; structural silicone;SSG; SSG design calculation; SSG design procedure; SSGevaluation; SSG installationsAPPENDIX(Nonmandatory Information)X1. BIBLIOGRAPHYX1.1 For more information see the fol
46、lowing:X1.1.1 Documents prepared by manufacturers and tradeassociations:X1.1.1.1 Structural Silicone Glazing, by Dow Corning Cor-poration.X1.1.1.2 Structural Silicone Glazing Guide, by GeneralElectric (GE Silicones) CompanyX1.1.1.3 Architectural Guidelines for Glazing Systems, byTremco CorporationX1
47、.1.1.4 Curtain Wall Manual No. 13, Structural SealantGlazing Systems (CW-13), AAMA, Schaumburg, Illinois,1985.X1.1.2 Books:X1.1.2.1 Sealants in Construction, Jerome M. Klosowski,Marcel Dekker, Inc., 1989.X1.1.2.2 Construction Sealants and Adhesives, Julian R.Panek or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).C1394 03 (2012)4
