Create an Account
Structural glass is used in a range of building applications, and while the ASTM E1300 has recently been updated to provide a design method to account for probabilistic failure models for a range of geometries under uniform loads, there does not exist detailed design information for point loads. While, ASTM E2751 provides an allowable stress based on a theoretical probability of breakage (POB) of 8/1000 from the appendix of ASTM E1300, these allowable stresses have only a loose correlation to POB and are not accurate for all glass configurations. To address this, the authors explore the effect of point loads on glass strength using the glass failure prediction model (GFPM) from E1300 to determines the allowable stress (or allowable load) for common glass lite geometry based on a POB of 8/1000 and 1/1000. Results allow practitioners to benchmark designs for monolithic and PVB laminated glass based on various point-support boundary conditions.
The parametric study investigates the maximum principle stresses and stress concentrations of specimen types subjected to out-of-plane bending due to a point load over 26 cm2(4 in2).The maximum point load is found for various 4-side supported glass lites at a POB of 8/1000 and 1/1000.
Structural glass applications, particularly façade and canopy elements, continue to grow in ubiquity as transparency and daylighting remain significant motivators of architectural design. However, current design procedures (i.e., elasticity and
A series of parametric finite element models were run using Abaqus FEA software (Abaqus, 2017) to obtain the maximum principle stresses and stress distributions. The modeling approach followed the methods
Maximum, deflections, U, principle stresses, S1, and stress distributions were found for the rectangular panels of varying aspect ratios (Figs 4-6). The stress distributions and deflected shapes of the panels
The design loads and related stresses presented in Figs 7-10, provide designers a simple reference for selection of geometries to meet desired POB for annealed and HS lites of 5.5
The results presented are for four side supported, 6 mm thick, annealed and HS glass types. Ongoing studies are being completed to build out a series of design tables for
The authors gratefully acknowledge Stutzki Engineering for the use of images.
ABAQUS: Multi-Purpose Finite Element Analysis Software, Dassault Systems. 2017
Afolabi, Bolaji, H. Scott Norville, and Stephen M. Morse. "Experimental study of weathered tempered glass plates from the Northeastern United States." Journal of Architectural Engineering 22, no. 3 (2016): 04016010.
ASTM International. ASTM E1300-16 Standard practice for determining load resistance of glass in buildings. West Conshohocken, Pennsylvania, USA. ASTM; 2016. www.astm.org p. 1-62.
ASTM International. ASTM E2751-17a. Standard Practice for Design and Performance of Supported Glass Walkways. West Conshohocken, Pennsylvania, USA. ASTM; 2017. www.astm.org p. 1-8.
Beason, W. Lynn, and James R. Morgan. "Glass failure prediction model." Journal of Structural Engineering 110, no. 2 (1984): 197-212.
Bowles, R., and B. Sugarman. "The strength and deflection characteristics of large rectangular glass panels under uniform pressure." Glass Technology 3, no. 5 (1962): 156-170.
Cervenka, J., Schultz, J.A., Stahl, D., and Knowles, J. “Strength of point-supported glass.” In Proceedings of the 1st Facade Tectonics World Congress; Tectonics Press Publications., pp. 381-389. 2016.
Charles, R. J. "Static fatigue of glass. I and II." Journal of Applied Physics 29, no. 11 (1958): 1549-1553.
Griffith, Alan A. "The phenomena of rupture and flow in solids." Philosophical transactions of the royal society of london. Series A, containing papers of a mathematical or physical character 221 (1921): 163-198.
Morse, S. and Norville, H. “An analytical method for determining window glass strength.” In Proceedings of Glass Performance Days 2011; GPD Press 9; pp. 480-482. 2011.
Morse, Stephen M., and H. Scott Norville. "Design methodology for determining the load resistance of heat-treated window glass." Journal of Architectural Engineering18, no. 1 (2011): 42-51.
Natividad, Kayla, Stephen M. Morse, and H. Scott Norville. "Fracture Origins and Maximum Principal Stresses in Rectangular Glass Lites." Journal of Architectural Engineering 22, no. 2 (2015): 04015014.
Orr, Leighton. "Engineering properties of glass." Publication 478 (1957): 51-61. Bowles and Sugarman, 1962;
Schultz, J.A., Knowles, J., and Morse, S., “Glass Failure Prediction Model for Out-of-Plane Bending of Waterjet-Drilled Holes,” In Proceedings of the 39th IABSE Symposium, International Associated of Bridge and Structural Engineers, Vancouver, Canada. 2017.
Schultz, Joshua, Douglas Stahl, and Christian Stutzki. "Experimental investigation of numerical design method for point-supported glass." Journal of Architectural Engineering18, no. 3 (2012): 223-232.
Vallabhan, CV Girija, Bob Yao-Ting Wang, Gee David Chou, and Joseph E. Minor. "Thin glass plates on elastic supports." Journal of Structural Engineering 111, no. 11 (1985): 2416-2426.
Vallabhan, CV Girija, Joseph E. Minor, and Sesha R. Nagalla. "Stresses in layered glass units and monolithic glass plates." Journal of structural Engineering 113, no. 1 (1987): 36-43.
Walker, G. R., and L. H. Muir. "Investigation of the Bending Strength of Glass Louvre Blades." In Ninth Australasian Conference on the Mechanics of Structures and Materials, ACMSM 9., pp. 122-126. 1984.
Weibull, Waloddi. "A statistical theory of the strength of materials." Ingeniors Vetenskaps Akademien (1939).