Test methodology for performance assessment of structural sealant glazing systems at superimposed mechanical and climatic loading

Durability assessment of structural sealant glazing systems applying a performance test method

“…Although it is challenging, if possible at all, to suggest loading parameters which represent a wide range of possible exposure conditions, it was attempted to design such a generalised durability test. [18,19] Supposing a model case building (Figure 1a), different design features and load scenarios were considered and combined following a worst-case approach to develop a test procedure that realises simultaneous weathering and mechanical loading (Figure 1b). Specifically designed medium-scale specimens ( Figure 2), referred to as system specimens, resemble a segment of a common SSG-bond.…”

“…Details on the development of the test are given in a previous publication. [19] One of the main goals of this study is the interpretation of the system response during laboratory exposure. The paper further studies effects of combined mechanical and climatic exposure on the conventional mechanical characteristics from tensile and shear tests in comparison with those of nonexposed reference specimens and specimens exposed only to the climatic loading function.…”

“…At the same time, changing ambient conditions lead to volume changes of the sealant bead, also affecting the actual stress state in the bond. [19] However, evaluation of the system response should give qualitative information on relative changes of characteristic mechanical parameters over the course of the test. Irrespective of exact measurement uncertainties, when only considering mechanical cycles that occur at the same temperature level, it is possible to exclude a temperature-induced error of stress and strain.…”

“…Another paper, which deals with performance assessment of SSG-joints, discusses these aspects in more detail. [19] This paper focusses on how the performance of the system specimens changes throughout the durability test. The following section discusses effects on the moduli.…”

“…A previous study showed that stress relaxation and modulus recovery occur at all three different strain amplitudes. [19] In this way, previous loading influences the system response. As ambient conditions also affect the dynamic mechanical characteristics and volume of the sealant, various effective load combinations occur during a 24 h climatic cycle.…”