Test Specimen Configurations

Silicone sealant properties and constitutive response are often derived from specimens in which the stress fields remain parallel during uniaxial loads. Ac­tual sealed joints in blast mitigating windows or curtainwalls, however, are exposed to extremely complicated stress fields that are still difficult to model based on the constitutive behavior of the sealant. Furthermore, the simple specimens used in deriving the constitutive response do not take adhesion or joint geometry into account; these factors need to be considered in the math­ematical modeling of the actual joints. As an interim step, the authors of this paper considered various specimen configurations that mimic actual sealed joints in blast mitigating window and curtainwall designs.

Specimen Type H0 (Tension and Compression Tests)—Test specimens were fabricated as tensile adhesion joints (H-pieces) as described in ASTM C1135 Test Method for Determining Tensile Adhesion Properties of Structural Seal­ants [37] and ETAG 002 Guideline for European Technical Approval for Struc­tural Sealant Glazing Kits with a sealed joint of dimensions 12 by 12 by 50 mm3 (width by height by length) between two (mill-finished) aluminum sub­Copyright by ASTM Int’l (all rights reserved); Tue May 6 11:22:28 EDT 2014 Downloaded/printed by

Rochester Institute Of Technology pursuant to License Agreement. No further reproductions authorized.

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FIG. 6—Configuration and dimensions of specimen Type M (dimensions given in millimetres).

strates of dimensions 40 by 5 by 50 mm3 (width by height by length).

Specimen Type HW (Tension)—Test specimens of Type HW were of the same configuration as Type H0, however, with one of the (mill-finished) aluminum substrates replaced by a float glass plate of dimensions 40 by 6 by 50 mm3 (width by height by length).

Specimen Type HS (Tension)—The tension test specimens of Type HS were similar to those of the Type H0, however with a smaller cross-sectional area, i. e., with a sealed joint of dimensions 12 by 6 by 50 mm3 (width by height by length) between two (mill-finished) aluminum substrates of dimensions 40 by 5 by 50 mm3 (width by height by length).

Specimen Type HL (Tension)—The tension test specimens of Type HS were similar to those of the Type H0, however with a larger cross-sectional area, i. e., with a sealed joint of dimensions 24 by 12 by 50 mm3 (width by height by length) between two (mill-finished) aluminum substrates of dimensions 40 by 5 by 50 mm3 (width by height by length).

Specimen Type M (Shear)—The configuration of specimen Type M is shown in Fig. 6. The specimen configuration comprises two symmetrically arranged joints, each having sealed joint dimensions of 12 by 12 by 50 mm3 (width by height by length) between two (mill-finished) aluminum substrates.

Specimen Type L (Combined Tension and Shear)—The configuration of specimen Type L is shown in Fig. 7. The specimen configuration comprises a U-shaped joint holding two L-shaped sealed joints between two (mill-finished) aluminum substrates.

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FIG. 7—Configuration and dimensions of specimen Type L (dimensions given in millimetres).