E − A The probability of breakages for Lite No. 1 and Lite Pb2 = e No. 2 for the load carried by each are as follows: A Conclusion— The. ASTM E – 12ae1. Standard Practice for Determining Load Resistance of Glass in Buildings. Active Standard ASTM E | Developed by Subcommittee: . Edition: 12ae1 (). Superseded by: ASTM E Check Published. Number of pages: Price: NOK 1 ,00 (excl. VAT) NOK 1 ,00 (with VAT).
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Thank you for interesting in our services. We are a non-profit group that run this website to share documents. We need your help to maintenance this website. Please help us to share our service with your friends. Home E – 12ae1 E – 12ae1 September 14, Author: A number in parentheses indicates the year of last reapproval. The values given in parentheses are for mathematical conversions to inch-pound units that are provided for information only and are not considered standard.
This practice shall not apply to other applications including, but not limited to, balustrades, glass floor panels, aquariums, structural glass members, and glass shelves. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
This practice assumes that 1 the supported glass edges for two, three, and four-sided support conditions are simply supported and free to slip in plane; 2 glass supported on two sides acts as a simply supported beam; and 3 glass supported on one side acts as a cantilever.
For insulating glass units, this practice only applies to insulating glass units with four-sided edge support. For glass simply supported on three sides, the ratio of the length of one of the supported edges perpendicular to the free edge, to the length of the free edge, is equal to or greater than 0.
The final thickness and type of glass selected also depends upon a variety of other factors see 5. Appendix X1 provides additional procedures to determine maximum lateral deflection for glass simply supported on four sides. Current edition approved May 1, Originally approved in Last previous edition approved in as E — If the sum of all interlayer thicknesses is greater than 1.
The construction of two 2. The information in this practice applies only to polyvinyl butyral PVB interlayer or those interlayers that demonstrate equivalency according to Appendix X8. Minimum Thickness, mm in. The specified design load shall be used for this calculation.
E 1300 – 12ae1
NOTE 1—This practice does not address aesthetic issues caused by glass deflection. These factors include but are not limited to: In addition, considerations set forth in building codes along with criteria presented in safety glazing standards and site specific concerns may control the ultimate glass type and thickness selection. If the maximum lateral deflection falls outside the charts in Annex A1, then use the procedures outlined in Appendix X1.
Summary of Practice 4. If the LR is less than the specified load, then other glass types and thicknesses may be evaluated to find a suitable assembly having LR equal to or exceeding the specified design load. Appendix X1 presents additional procedures to determine 12ze1 approximate maximum lateral deflection for a specified load on glass simply supported on four sides. Significance and Use 5. If the maximum lateral deflection falls outside the charts in Annex A1, e1300 use the procedures outlined — X1.
Zstm 2—Values are approximated. Use Vallabhan and Chou 1 for alternate method. See Appendix X3 for basis of these values. If the LR ast, greater than or equal to the specified design load, then the glass types and thicknesses are acceptable for a breakage probability of less than, or equal to, 8 in NOTE 4—The user is recommended to limit the combined width of both air spaces in the IG unit to less than or equal to 25 mm 1 in.
A larger combined dimension may result in excessive sealant stress and glass stresses due to temperature and altitude conditions. It is possible that the information presented in awtm NFL charts may change as further data becomes available.
Precision and Bias 8. Complete discussions of the formulation of the model are presented elsewhere 2, 3. The NFL charts were developed using a failure prediction model for glass 4, 5. The model allows the probability of breakage of any lite or ply to be specified in terms of two surface flaw parameters, m and k. No recommendations are made in this practice regarding acceptable lateral deflections.
The lower charts of Fig. In development of the NFL charts presented in upper charts of Fig. These flaw parameters represent the surface strength of weathered window glass that has undergone in-service conditions for approximately 20 years.
The selection of the surface flaw parameters was based upon the best available data and engineering judgment. If the charts are used to predict the strength of freshly manufactured glass, the results may be conservative.
This method does not apply to glass that has been subjected to severe surface degradation or abuse such as weld splatter or sand blasting. These minimum glass thicknesses are presented in Table 4. Glass may be manufactured thicker than those minimums.
The NFL is thus found to be 2. Convert kPa to inch-pound units by multiplying 2. Example 4 illustrates the determination of approximate center of glass deflection. The outboard lite Lite No. Determine if the skylight will support a 6. Therefore the LR of the IG is: Approximate Center of Glass Deflection Determination in SI Units—Determine the approximate center of glass deflection associated with a vertical by by 6-mm rectangular glass plate subjected to a uniform lateral load of 1.
Will this window glass support a 1. This leaves a short term duration LR for the IG unit of: Lateral Deflection Calculation in SI Units Using Method X2—Determine the maximum lateral deflection w of a vertical by by 6-mm rectangular glass plate subjected to a uniform lateral load of 1. The actual thickness of the glass is 5.
The actual thickness of the glass is 0. Such deflections, which will exceed the lite thickness, should be rounded to the nearest mm 0. For aspect ratios greater than 5, use 5. Rigorous engineering analysis that accounts for the geometrically nonlinear performance of glass lites, glass surface condition, residual surface compression, surface area under stress, geometry, support conditions, load type and duration, and other relevant parameters can result in other type factors.
Therefore the AN lite probability factor becomes: As the area of glass under a given stress increases there is an increased risk of breakage occurring. For a single monolithic lite with two surfaces equally at risk, p 5 1. This is due to sealed air space pressure differences caused by changes in: The factor for all IG units is: Where membrane stresses predominate, the exponent is less than 3 but this regime is outside the range of typical architectural glass design.
Under short duration loads LG is assumed to behave in a monolithic-like manner. The glass thickness used for calculating load sharing factors for short duration loads is the sum of the thickness of glass of the 2 plies in accordance with Table 1.
The load sharing is then based on the individual ply thicknesses of the LG.
The LS factor for one ply of the laminated lite of an IG composed of: Similarly the LS factor for Lite No. To convert, multiply the LR by the factor in Table X4.
Duration Factor 3s 10 s 60 s 10 min 60 min 12 h 24 h 1 week 1 month 30 days 1 year beyond 1 year 1. All loads are considered normal to the glass surface. Use the following equation to calculate the equivalent 3-s duration design load: The maximum allowable stress allowable is a function of area Aload duration in seconds dand probability of breakage Pb. This includes trapezoids, circular, triangular, and other odd shapes.
E – 12ae1 – Free Download PDF
A conservative allowable surface stress value for a 3-s duration load is This maximum calculated stress must be less than the maximum allowable stress. Note that Section 6 references a Pb less than or equal to 0. This includes applications where the glass is not supported on one or more edges.
An approximate allowable edge stress value for a 3-s duration can be found in Table X7. Polished Edges, MPa psi Astj comprised of differing polymers in multiple layers are not covered in this procedure. Two different effective laminate thickness values are determined for a specific case: These effective thickness values can be used with standard engineering formulae or finite element methods for calculating both deflection and glass stress of laminates subjected to load.
The method applies to 2-ply laminates fabricated from both equal and unequal thickness glass plies. The intent of Appendix X9 is to provide a method that allows the user to perform engineering analysis of lami- X9.
Contact the interlayer manufacturer for appropriate shear modulus values. The beam is fixed along one long edge cantilever and is subjected to a line load, P, of 0. The proposed laminate construction is 10 mm glass 1. For these loading duration and temperature considerations the interlayer shear modulus, G, asm determined to be 0. Substituting into Eq X9.