End of life considerations of silicone bonded glazing
Global construction industry and regulations target circularity in buildings and lower embodied carbon. Following this trend, commercial buildings are more frequently considered for refurbishment for reuse as commercial or residential building. During the refurbishment, part of the constitutive elements, such as glass and aluminum frame, are reused in the renovated façade. Alternatively, the whole façade could be kept in place if sufficient remaining lifetime expectancy of the constitutive elements can be confirmed.
Silicone bonded glazing façades are recognized as a durable, energy and material efficient façade system. However, uncertainty exists as how to refurbish, reuse and/or extend lifetime this type of façades. Recommendations on how to debond units, how to assess the quality of the old sealant and how to rebond are needed. This paper will review different disassembly and testing methods to evaluate the quality on different types of bonding silicone and the rebonding procedure. The refurbishment of the CITIBANK tower in London which was originally structurally glazed with DOWSIL™ 993 Structural glazing sealant is used as case study to illustrate the various steps.
Case Study of FE Modeling Approaches for SSG in Blast
Designing for blast performance for glazing units can be very complex. The test methods for evaluating performance include subjecting units to actual or simulated blast conditions, which occur rapidly on a very short time scale. Connecting laminated glass to a metal frame using structural silicone sealant creates a unique composite based on the use of a brittle plate with an elastic soft rubber to a ductile rigid metal.
Glazed units were tested with a shock tube charged with various levels of explosive to record the damage development with various modes of failure of the material. Two test results were modeled to compare to the actual observations. Based on the outcome, techniques for effective modeling are discussed as well as future needs.
Understanding Stress Distributions in Wet Glazed Glass Railing Systems
Glass railing systems have become increasingly popular due to their ability to provide unobstructed views and exceptional durability. While mechanical fixation methods are available, glass embedment is often preferred for its aesthetic and structural benefits. Wet glazed glass embedment systems for balustrades involve securing glass panels materials using a polymeric resin, sealant, or grout. These systems must comply with stringent standards and building codes to meet specific safety requirements, making it crucial to understand the performance of the materials involved. This study aimed to develop a comprehensive understanding of stress distribution in polymeric glass embedment materials as a part of a glass rail system. By combining finite element modeling and experimental testing, the research analyzed how these materials behave under both wind loading and line loads. The goal was to develop dimensioning equations to optimize embedding design parameters, ensuring safety and performance. The findings are supported by a case study, which provides practical insights into the real-world application of the developed models and material. This case study highlights the importance of accurate stress distribution analysis in preventing failures and ensuring the performance of glass railing systems. The research contributes to the field by offering a framework for better understanding design factors that impact the stress state of glass balustrade systems. These learnings are valuable as they offer context for utilizing embedment materials in various applications beyond glass rail systems, including windscreens, dead load support, and panel stiffening.
