1、Designation: E2751 11Standard Practice forDesign and Performance of Supported Glass Walkways1This standard is issued under the fixed designation E2751; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A nu
2、mber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice addresses elements related to load-bearingglass walkways, glass treads, and glass landings constructedwith laminated glass.
3、 This standard includes performance,design, and safe behavior considerations. It addresses thecharacteristics unique to glass and laminated glass. Issues thatare common to all walkways, such as slip resistance, areaddressed in existing referenced standards.1.2 This practice does not address glass wa
4、lkways con-structed with monolithic glass, glass block, insulating glassunits, glass tiles that are directly bonded to a non-glassstructural substrate, or glass walkways intended to supportvehicular traffic.1.3 The values stated in SI units are to be regarded as thestandard. The values given in pare
5、ntheses are for mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establ
6、ish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C1028 Test Method for Determining the Static Coefficientof Friction of Ceramic Tile and Other Like Surfaces by theHorizontal Dynamometer Pul
7、l-Meter MethodC1036 Specification for Flat GlassC1048 Specification for Heat-Treated Flat GlassKind HS,Kind FT Coated and Uncoated GlassC1172 Specification for Laminated Architectural Flat GlassE631 Terminology of Building ConstructionsE1300 Practice for Determining Load Resistance of Glassin Buildi
8、ngsF609 Test Method for Using a Horizontal Pull Slipmeter(HPS)2.2 ANSI Standards:3ANSI/ASSE TR-A1264.3-2007 ANSI Technical Report,Using Variable Angle Tribometers (VAT) for Measure-ment of the Slip Resistance of Walkway Surfaces2.3 UL Standards:4UL 410 Standard for Safety for Slip Resistance of Floo
9、rSurface Materials3. Terminology3.1 DefinitionsFor definitions of general terms related tobuilding construction used in this practice, refer to Terminol-ogy E631.3.2 Definitions of Terms Specific to This Standard:3.2.1 duration of loadthe period of continuous applica-tion of a given load, or the agg
10、regate of periods of intermittentapplications of the same load.3.2.1.1 DiscussionAny load duration longer than onehour shall be considered a permanent load. Uniformly distrib-uted live loads shall have a load duration of at least one hour.Concentrated live loads shall have a load duration of at leas
11、tten minutes.3.2.2 ethylene vinyl acetate (EVA) interlayerco-polymerof ethylene and vinyl acetate used to permanently bond two ormore lites of glass.3.2.3 glass-clad polycarbonate laminateassembly con-sisting of two or more lites of glass and one or more sheets ofpolycarbonate bonded by interlayers.
12、3.2.4 ionomer interlayera partially neutralized copolymerof ethylene and acrylic or methacrylic acid, used to perma-nently bond two or more lites of glass.3.2.5 laminated glassan assembly consisting of two ormore lites of glass bonded by an interlayer.3.2.6 liquid resin interlayerliquid formulations
13、, generallypolyester-, urethane-, or acrylic-based, that react to form solidinterlayers after being introduced between two lites of glass.3.2.7 polyurethane interlayerpolymer sheeting based onisocyanates and mostly polyester or acrylic polyols, or both.1This practice is under the jurisdiction of AST
14、M Committee E06 on Perfor-mance of Buildings and is the direct responsibility of Subcommittee E06.56 onPerformance of Railing Systems and Glass for Floors and Stairs.Current edition approved Oct. 1, 2011. Published October 2011. DOI: 10.1520/E2751-11.2For referenced ASTM standards, visit the ASTM we
15、bsite, 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.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, ht
16、tp:/www.ansi.org.4Available from Underwriters Laboratories (UL), 2600 N.W. Lake Rd., Camas,WA 98607-8542, http:/.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.8 polyvinyl butyral (PVB) interlayerpolymer sheetingprepared from po
17、lyvinyl alcohol by reaction with butyralde-hyde used to permanently bond two or more lites of glass.3.2.9 post-breakage glass retentionthe ability of the bro-ken glass to remain in place so as to reduce cutting and piercinginjuries from the broken shards and to prevent fall through orglass fallout.3
18、.2.10 slip resistantthe provision of adequate slip resis-tance to reduce the likelihood of slip for pedestrians usingreasonable care on the walking surface under expected useconditions.3.2.11 supported glass walkwayany glass walkway with afree spanning section, including continuous or local multiple
19、supports at the edge or any location of the glass.3.2.12 walkway surfacesinterior and exterior walking sur-faces constructed and intended for pedestrian use, includingbut not limited to floors, ramps, sidewalks, and stair treads.4. Significance and Use4.1 Glass is a brittle material with different t
20、ime andtemperature-dependent properties than other solid materialsused as walkways surfaces. Therefore, the type of glass is animportant consideration in the design and construction of glasstreads and glass landings constructed with laminated glass.4.2 Post-breakage glass retention is an important c
21、onsider-ation in the design of a glass walkway system as a means ofminimizing tripping, cutting/piercing injuries, or fall-throughor fallout of the glass.4.3 The structural design shall be confirmed by calculationsby a licensed design professional in accordance with Section 5.4.4 The post-breakage b
22、ehavior of the glass walkway shallbe verified by testing in accordance with Section 6.4.4.1 For laminates with two glass plies, verification testingis required.4.4.2 For laminates with more than two glass plies, verifi-cation testing is not required provided that calculations com-pleted in accordanc
23、e with 4.3 demonstrate that the glassassembly has sufficient strength to sustain the full design loadwith any one glass ply broken.4.4.3 When verifying post-breakage behavior by calcula-tion, allowable glass stress for 10 min load duration in accor-dance with Table 1 shall be used for all load cases
24、.4.5 The manufacturer or designer of glass walkway systemsshall provide installation directions and fabrication and instal-lation tolerances of their systems.4.6 The structural integrity of the glass walkway systemafter glass breakage shall be sufficient to support the designloads after any one glas
25、s ply is broken. If damage of any kindoccurs, the walkway shall be cordoned off and the installationshall be inspected to ensure structural integrity and pedestriansafety of the system.5. Calculation Procedure5.1 Use established engineering methods, such as engineer-ing mechanics or finite element a
26、nalysis, to determine glassassembly stresses and deflections. Such methods shall accountfor temperature, boundary conditions, loading requirements,load duration, interlayer properties, and glass strength.5.2 Design Criteria:5.2.1 Assign nominal load conditions or combinations ofload conditions as re
27、quired by the specifying authority. Addi-tionally, the final design shall include consideration of aconcentrated live load of at least 136 kg (300 lb) applied to allglass walking surfaces in a 2600 mm2(4 in.2) area.5.2.2 Determine maximum allowable material stress.5.2.2.1 GlassRefer to Table 1 to de
28、termine allowableglass stress.(1) Use minimum glass thickness in accordance withSpecification C1036, Table 2, for design purposes.5.2.2.2 InterlayerConsult the interlayer manufacturer forinterlayer material properties, load duration and temperaturebehavior. Typical interlayers are PVB, ionomer, liqu
29、id resin,EVA, and polyurethane.5.2.2.3 Other Laminate MaterialsConsult the supplier forproperties of other laminate materials, such as polycarbonate.5.2.3 The structural support system shall provide sufficientstrength to support the combined applicable loads.5.2.4 Deflection of the floor members sha
30、ll conform torelevant building code requirements.6. Post-breakage Verification Test Methods6.1 Assign nominal load conditions or combinations of loadconditions as required by the specifying authority.6.2 Test for the dominant load case (uniform load orconcentrated load) as determined by calculations
31、 in accordancewith Section 5.6.3 Test the glass as a system with frame and attachments.6.4 For walkways with two supported edges, test a panelwith the largest span between supports. For walkways withthree or more supported edges, test the sample size thatrepresents the most demanding or highest stre
32、ss condition.6.5 Condition glass for at least four hours at the sametemperature at which it will be tested.6.6 Conduct testing at the maximum temperature for theintended use environment. When the intended end use envi-ronment is unknown, conduct testing at 50C and 0C 6 5C.6.7 Concentrated Load Testi
33、ng:6.7.1 Break any one glass lite to produce the most unfavor-able results. The worst case condition shall be determined byanalysis or all combinations of broken glass shall be tested.TABLE 1 Allowable Glass Stresses for Nominal Load ConditionsNOTE 1An allowable stress reduction factor of 0.5 is rec
34、ommendedfor disruptive surface treatments, for example, acid etching or sandblast-ing, unless otherwise provided by the manufacturer. A glass stressreduction factor may be required for some patterned glasses; consult themanufacturer.NOTE 2Values derived from Practice E1300, Table X9.1 (seamededges),
35、 factored for load duration using Practice E1300, Equation X7.1,where n = 16 for annealed glass, n = 32 for heat strengthened glass, andn = 48 for tempered glass.Glass Type3-secMPa (psi)10-minMPa (psi)60-minMPa (psi)PermanentMPa (psi)Annealed 18.3 (2650) 13.2 (1902) 11.7 (1701) 5.7 (827)Heat-strengt
36、hened 36.5 (5300) 30.9 (4482) 29.2 (4235) 20.3 (2944)Tempered 73.0 (10 600) 65.3 (9471) 63.0 (9137) 49.4 (7165)E2751 1126.7.2 Apply the specified load over a 2600 mm2(4 in.2)area at a rate of 45.4 kg (100 lbs) per minute up to the designload and hold for a duration of 10 min.6.7.3 At the conclusion
37、of testing, no additional glass pliesshall have broken.6.8 Uniform Load Testing:6.8.1 Break any one glass lite to produce the most unfavor-able results. Worst case condition shall be determined byanalysis or all combinations of broken glass shall be tested.6.8.2 Apply the specified uniform load at a
38、 rate of 30 psf/min up to the design pressure and hold for a duration of 60 min.6.8.3 At the conclusion of testing, no additional glass pliesshall have broken.7. Other Considerations7.1 Slip Resistance:7.1.1 A minimum coefficient of friction of 0.5 is recom-mended for walking surfaces under dry cond
39、itions. Wet orcontaminated conditions may require the use of special pre-cautions and measures to minimize the risk of slips and falls.7.1.2 Non-level walkways or walkways on which otherspecial activities take place, such as lifting, running, athleticactivities, may require a higher level of slip re
40、sistance.7.1.3 Appropriate levels of slip resistance can be accom-plished through a variety of glass surface treatments, includingsandblasting, acid-etching, ceramic frit, embossing, kilncasting/fusing, and other processes designed to treat the walk-ing surface.7.1.4 The selection of the slip resist
41、ant treatment shall bemade according to the intended use and desired durability ofthe walking surface.7.1.5 Evaluate slip resistance using one of the following testmethods or by other methods selected as appropriate for use:7.1.5.1 Test Method C10287.1.5.2 Test Method F6097.1.5.3 UL 4107.1.5.4 ANSI/
42、ASSE TR-A1264.3-20077.2 Materials:7.2.1 Glass SelectionGlass selection is based on manyfactors, including strength, fabrication, durability, aesthetics,cost, and glass post- breakage behavior.7.2.1.1 Annealed GlassRefer to Specification C1036 forrequirements pertaining to flat glass.7.2.1.2 Heat-Str
43、engthened GlassRefer to SpecificationC1048 for requirements pertaining to heat-strengthened glass.7.2.1.3 Tempered GlassRefer to Specification C1048 forrequirements pertaining to tempered glass.7.2.1.4 Laminated GlassRefer to Specification C1172 forrequirements pertaining to laminated glass.7.2.2 In
44、terlayer SelectionInterlayer selection is based onmany factors, including strength, fabrication, durability, aes-thetics, cost, and glass post-breakage behavior.7.3 Structural Support System:7.3.1 The glass edge support system shall be sufficientlystiff to limit the deflection of the supported glass
45、 edges underthe design load to no more than L/500 of their lengths, whereL is the supported length of the glass, unless analysis takinginto account frame deflection effects on glass stress is carriedout in combination with the design loads in accordance withSection 5.7.3.2 The glass shall be cushion
46、ed to prevent direct contactwith the glass support system.7.4 Dynamic Use Considerations:7.4.1 The licensed design professional shall consider thenecessity of a glass floor systems vibration review, and ifnecessary, perform such review. Considerations may includesystem continuity, supports, and defl
47、ection compatibility withadjacent structures.7.5 Fire Resistance Requirements:7.5.1 Glass walkways shall provide a fire rating whenrequired by the authority having jurisdiction.7.6 Visual Cues:7.7 Glass walkways present a special challenge in balancingthe visual characteristics of glass with conside
48、rations of safety.Visual cues of conditions that impair the ability of pedestriansto walk safely shall be incorporated into the glass walkwaydesign.8. Durability8.1 The walking surface of the glass shall be designed withsuitable durability for the specified application. In cases whereuse of the walk
49、way eventually reduces its slip resistance,instruction shall be provided to the end user regarding safemaintenance and replacement requirements.8.2 The use of cleaning and maintenance equipment shall betested for compatibility with the glass walking surface andwalking surface components.9. Keywords9.1 annealed glass; heat-strengthened glass; glass; glassfloor; glass stair treads; glass walkways; laminated glass;tempered glassE2751 113ASTM International takes no position respecting the validity of any patent rights asserted in connection with
