1、Designation: E2751 11E2751 12Standard Practice forDesign and Performance of Supported Laminated GlassWalkways1This 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 la
2、st revision. A number 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-bearing glass walkways, glass treads, and glass landings constructed wi
3、thlaminated glass. This standard includes performance, design, and safe behavior considerations. It addresses the characteristicsunique to glass and laminated glass. Issues that are common to all walkways, such as slip resistance, are addressed in existingreferenced standards.1.2 This practice does
4、not address glass walkways constructed with monolithic glass, glass block, insulating glass units, glasstiles that are directly bonded to a non-glass structural substrate, or glass walkways intended to support vehicular traffic.1.3 The values stated in SI units are to be regarded as the standard. Th
5、e values given in parentheses are for mathematicalconversions to inch-pound units that are provided for information only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of t
6、his standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C1028 Test Method for Determining the Static Coefficient of Friction of Ceramic Tile and Other Like Surfaces by the Horiz
7、ontalDynamometer Pull-Meter MethodC1036 Specification for Flat GlassC1048 Specification for Heat-Strengthened and Fully Tempered Flat GlassC1172 Specification for Laminated Architectural Flat GlassE631 Terminology of Building ConstructionsE1300 Practice for Determining Load Resistance of Glass in Bu
8、ildingsF609 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 Measurement of the SlipResistance of Walkway Surfaces2.3 UL Standards:4UL 410 Standard for Safety for Slip Resistance of
9、Floor Surface Materials3. Terminology3.1 DefinitionsFor definitions of general terms related to building construction used in this practice, refer to TerminologyE631.3.2 Definitions of Terms Specific to This Standard:1 This practice is under the jurisdiction of ASTM Committee E06 on Performance of B
10、uildings and is the direct responsibility of Subcommittee E06.56 on Performanceof Railing Systems and Glass for Floors and Stairs.Current edition approved Oct. 1, 2011Nov. 1, 2012. Published October 2011December 2012. Originally approved in 2011. Last previous edition approve in 2011 as E2751 11. DO
11、I: 10.1520/E2751-11.10.1520/E2751-12.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from America
12、n National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.4 Available from Underwriters Laboratories (UL), 2600 N.W. Lake Rd., Camas, WA 98607-8542, http:/.This document is not an ASTM standard and is intended only to provide the user of an ASTM standar
13、d an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM i
14、s to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.1 duration of loadthe period of continuous application of a given load, or the aggregate of periods of intermittentapplications of the same l
15、oad.3.2.1.1 DiscussionAny load duration longer than one hour shall be considered a permanent load. Uniformly distributed live loads shall have a loadduration of at least one hour. Concentrated live loads shall have a load duration of at least ten minutes.3.2.2 ethylene vinyl acetate (EVA) interlayer
16、co-polymer of ethylene and vinyl acetate used to permanently bond two or morelites of glass.3.2.3 glass-clad polycarbonate laminateassembly consisting of two or more lites of glass and one or more sheets ofpolycarbonate bonded by interlayers.3.2.4 ionomer interlayera partially neutralized copolymer
17、of ethylene and acrylic or methacrylic acid, used to permanentlybond two or more lites of glass.3.2.5 laminated glassan assembly consisting of two or more lites of glass bonded by an interlayer.3.2.6 liquid resin interlayerliquid formulations, generally polyester-, urethane-, or acrylic-based, that
18、react to form solidinterlayers after being introduced between two lites of glass.3.2.7 polyurethane interlayerpolymer sheeting based on isocyanates and mostly polyester or acrylic polyols, or both.3.2.8 polyvinyl butyral (PVB) interlayerpolymer sheeting prepared from polyvinyl alcohol by reaction wi
19、th butyraldehydeused to permanently bond two or more lites of glass.3.2.9 post-breakage glass retentionthe ability of the broken glass to remain in place so as to reduce cutting and piercinginjuries from the broken shards and to prevent fall through or glass fallout.3.2.10 slip resistantthe provisio
20、n of adequate slip resistance to reduce the likelihood of slip for pedestrians using reasonablecare on the walking surface under expected use conditions.3.2.11 supported glass walkwayany glass walkway with a free spanning section, including continuous or local multiplesupports at the edge or any loc
21、ation of the glass.3.2.12 walkway surfacesinterior and exterior walking surfaces constructed and intended for pedestrian use, including but notlimited to floors, ramps, sidewalks, and stair treads.4. Significance and Use4.1 Glass is a brittle material with different time and temperature-dependent pr
22、operties than other solid materials used aswalkways surfaces. Therefore, the type of glass is an important consideration in the design and construction of glass treads andglass landings constructed with laminated glass.4.2 Post-breakage glass retention is an important consideration in the design of
23、a glass walkway system as a means ofminimizing tripping, cutting/piercing injuries, or fall-through or fallout of the glass.4.3 The structural design shall be confirmed by calculations by a licensed design professional in accordance with Section 5.4.4 The post-breakage If testing is required (see 4.
24、4.1-4.4.3) to verify post-glass breakage behavior of the glass walkwaywalkway, the testing shall be verified by testing in accordance with Section 6.4.4.1 For laminates with two glass plies, verification testing is required.4.4.2 For laminates with more than two glass plies, verification testing is
25、not required provided that calculations completed inaccordance with 4.3 demonstrate that the glass assembly has sufficient strength to sustain the full design load with any one glassply broken.4.4.3 When verifying post-breakage behavior by calculation, allowable glass stress for 10 min load duration
26、 in accordance withTable 1 shall be used for all load cases.4.5 The manufacturer or designer of glass walkway systems shall provide installation directions and fabrication and installationtolerances of their systems.4.6 The structural integrity of the glass walkway system after glass breakage shall
27、be sufficient to support the design loads afterany one glass ply is broken. If damage of any kind occurs, the walkway shall be cordoned off and the installation shall be inspectedto ensure structural integrity and pedestrian safety of the system.5. Calculation Procedure5.1 Use established engineerin
28、g methods, such as engineering mechanics or finite element analysis, to determine glass assemblystresses and deflections. Such methods shall account for temperature, boundary conditions, loading requirements, load duration,interlayer properties, and glass strength.E2751 1225.2 Design Criteria:5.2.1
29、Assign nominal load conditions or combinations of load conditions as required by the specifying authority. Additionally,the final design shall include consideration of a concentrated live load of at least 136 kg (300 lb) applied to all glass walkingsurfaces in a 2600 mm2 (4 in.2) area.5.2.2 Determin
30、e maximum allowable material stress.5.2.2.1 GlassRefer to Table 1 to determine allowable glass stress.(1) Use minimum glass thickness in accordance with Specification C1036, Table 2, for design purposes.5.2.2.2 InterlayerConsult the interlayer manufacturer for interlayer material properties, load du
31、ration and temperaturebehavior. Typical interlayers are PVB, ionomer, liquid resin, EVA, and polyurethane.5.2.2.3 Other Laminate MaterialsConsult the supplier for properties of other laminate materials, such as polycarbonate.5.2.3 The structural support system shall provide sufficient strength to su
32、pport the combined applicable loads.5.2.4 Deflection of the floor members shall conform to relevant building code requirements.6. Post-breakage Verification Test Methods6.1 Assign nominal load conditions or combinations of load conditions as required by the specifying authority.6.2 Test for the domi
33、nant load case (uniform load or concentrated load) as determined by calculations in accordance withSection 5.6.3 Test the glass as a system with frame and attachments.6.4 For walkways with two supported edges, test a panel with the largest span between supports. For walkways with three ormore suppor
34、ted edges, test the sample size that represents the most demanding or highest stress condition.6.5 Condition glass for at least four hours at the same temperature at which it will be tested.6.6 Conduct testing at the maximum temperature for the intended use environment. When the intended end use env
35、ironment isunknown, conduct testing at 50C and 0C 6 5C.6.7 Concentrated Load Testing:6.7.1 Break any one glass lite to produce the most unfavorable results. The worst case condition shall be determined by analysisor all combinations of broken glass shall be tested.6.7.2 Apply the specified load over
36、 a 2600 mm2 (4 in.2) area at a rate of 45.4 kg (100 lbs) per minute up to the design load andhold for a duration of 10 min.6.7.3 At the conclusion of testing, no additional glass plies shall have broken.6.8 Uniform Load Testing:6.8.1 Break any one glass lite to produce the most unfavorable results.
37、Worst case condition shall be determined by analysis orall combinations of broken glass shall be tested.6.8.2 Apply the specified uniform load at a 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 plies shall have
38、broken.7. Other Considerations7.1 Slip Resistance:7.1.1 A minimum static coefficient of friction of 0.5 is recommended for walking surfaces under dry conditions. Wet orcontaminated conditions may require the use of special precautions and measures to minimize the risk of slips and falls.TABLE 1 Allo
39、wable Glass Stresses for Nominal Load ConditionsNOTE 1An allowable stress reduction factor of 0.5 is recommendedfor disruptive surface treatments, for example, acid etching orsandblasting, unless otherwise provided by the manufacturer. A glassstress reduction factor may be required for some patterne
40、d glasses; consultthe manufacturer.NOTE 2Values derived from Practice E1300, Table X9.1 (seamededges), factored for load duration using Practice E1300, Equation X7.1,whereusing n = 16 for annealed glass, n = 32 for heat strengthened glass,and n = 48 for tempered glass.Glass Type 3-secMPa (psi) 10-mi
41、nMPa (psi) 60-minMPa (psi) PermanentMPa (psi)Annealed 18.3 (2650) 13.2 (1902) 11.7 (1701) 5.7 (827)Heat-strengthened36.5 (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 1237.1.2 Non-level walkways or walkways on which other special activities
42、 take place, such as lifting, running, athletic activities,may require a higher level of slip resistance.7.1.3 Appropriate levels of slip resistance can be accomplished through a variety of glass surface treatments, includingsandblasting, acid-etching, ceramic frit, embossing, kiln casting/fusing, a
43、nd other processes designed to treat the walking surface.7.1.4 The selection of the slip resistant treatment shall be made according to the intended use and desired durability of thewalking surface.7.1.5 Evaluate slip resistance using one of the following test methods or by other methods selected as
44、 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/ASSE TR-A1264.3-20077.2 Materials:7.2.1 Glass SelectionGlass selection is based on many factors, including strength, fabrication, durability, aesthetics, cost, andglass post- breakage behavior.7.2.1.1 An
45、nealed GlassRefer to Specification C1036 for requirements pertaining to flat glass.7.2.1.2 Heat-Strengthened GlassRefer to Specification C1048 for requirements pertaining to heat-strengthened glass.7.2.1.3 Tempered GlassRefer to Specification C1048 for requirements pertaining to tempered glass.7.2.1
46、.4 Laminated GlassRefer to Specification C1172 for requirements pertaining to laminated glass.7.2.2 Interlayer SelectionInterlayer selection is based on many factors, including strength, fabrication, durability, aesthetics,cost, and glass post-breakage behavior.7.3 Structural Support System:7.3.1 Th
47、e glass edge support system shall be sufficiently stiff to limit the deflection of the supported glass edges under the designload to no more than L/500 of their lengths, where L is the supported length of the glass, unless analysis taking into account framedeflection effects on glass stress is carri
48、ed out in combination with the design loads in accordance with Section 5.7.3.2 The glass shall be cushioned to prevent direct contact with the glass support system.7.4 Dynamic Use Considerations:7.4.1 The licensed design professional shall consider the necessity of a glass floor systems vibration re
49、view, and if necessary,perform such review. Considerations may include system continuity, supports, and deflection compatibility with adjacentstructures.7.5 Fire Resistance Requirements:7.5.1 Glass walkways shall provide a fire rating when required by the authority having jurisdiction.7.6 Visual Cues:7.7 Glass walkways present a special challenge in balancing the visual characteristics of glass with considerations of safety.Visual cues of conditions that impair the ability of pedestrians to walk safely shall be incorporated into the glass w
