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In this research study, the fracture strength of flat 10 mm thick annealed glass sheets having an abrasive water-jet cut surface and bearing against a transparent interface material is experimentally investigated. The transparent interface material is necessary to provide axial-compressive force continuity in modular compression-dominant all- glass shell structures. A series of short glass columns were tested in axial compression under a variety of load cases, which included cyclic, creep, and monotonic-to-fracture loading. A target glass fracture bearing stress of 36.6 MPa is identified and represents an upper bound bearing stress for annealed glass compression members failing in a flexural buckling mode. The study concludes the transparent thermoplastic material, known as Surlyn, was able to achieve a fracture strength that exceeds the target value and that the fracture strength is not affected by cyclic or creep loading. Consequently, column-related failure limit states will occur before glass fracture is associated with interface bearing. Glass fracture occurs in Type-I mode, reflecting the presence of interface tensile stress. Furthermore, the monotonic bearing stiffness in the service range of 5 to 15 MPa is increased by 20 % and 16 % for samples subjected to cyclic and creep loading, respectively, relative to monotonic-only samples.
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Effects of acid leaching treatment of soda‐lime silicate glass on crack initiation and fracture
Abstract Water or acid soaking surface treatments have been shown to increase the mechanical strength of soda‐lime silicate (SLS) glasses. This increase in strength has traditionally been attributed to effects related to residual stress or changes in fracture resistance. In this work, we report experimental data that cannot be explained based on the existing knowledge of glass surface mechanics. In dry environments, annealed and acid‐leached SLS surfaces have comparable crack initiation stress and fracture stress as measured by Hertzian indentation and biaxial bending tests, respectively. Yet, in the presence of humidity, acid‐leached surfaces have higher failure stress than the annealed surfaces. This apparent enhancement in the crack resistance of the acid‐leached surface of SLS glass in humid environments supports the hypothesis that acid‐leached surface chemistry can lower the transport kinetics of molecular water to critical flaws.
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- Award ID(s):
- 2011410
- PAR ID:
- 10449055
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of the American Ceramic Society
- Volume:
- 104
- Issue:
- 9
- ISSN:
- 0002-7820
- Page Range / eLocation ID:
- p. 4550-4558
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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