Improvement of glass curtain wall connections subjected to quasistatic and dynamic loading

Extreme events, such as explosions, can significantly compromise the structural integrity of buildings. Currently, glass curtain wall (CW) systems are widely used as façade solutions in government, educational, medical, and commercial structures. However, advancements in manufactured and improvised explosive devices (IEDs) have resulted in a rise in explosive incidents and related injuries in recent years. Despite their widespread use, there has been limited experimental research on full-scale CW system connections. This study aims to address this gap by developing blast design and retrofit connection recommendations for modern curtain walls through quasi-static and dynamic testing of curtain wall mullions and connections. Several studies were conducted to assess the conventional design of glass curtain wall connection and explore ways to enhance the connections for improved mechanical properties. The initial test involved a quasi-static evaluation of a 1219.2 mm (48 in) long mullion specimen. The widely used conventional T anchor connection was tested first, followed by five additional strengthening techniques. These techniques included: a through bolt connecting the mullion and T anchor, a steel C channel insert, a steel C channel insert with through bolts, aluminum and steel bearing angles, and a closed T anchor stem design. Each of these designs was compared to the conventional model to evaluate the mechanical advantages provided by the strengthening techniques. Preliminary experimental work for dynamic loading was initiated on both the conventional and strengthened connections. A drop weight machine was used to apply dynamic loads to the 1219.2 mm (48 in) long mullion specimens, utilizing piezoelectric load cells to measure the reactions at each end and the load applied at the midspan of the mullion. These results were used to help develop a dynamic increase factor (DIF) to help correlate the responses from the quasistatic testing to the dynamic testing in terms of peak load. Finally, experimental work was conducted on full-scale mullion specimens subjected to quasi-static loads. These samples demonstrated the behavioral differences between flexural failure and shear failure in the mullion specimens. The results from these tests varied from those of the 1219.2 mm (48 in) long mullion specimens. Load and deflection data were collected for all tests, which are detailed in the results section below. Understanding how strengthening the connections in a full-scale glass curtain wall system can improve energy absorption is crucial for designing against catastrophic events like blast explosions. This paper discusses these key characteristics and offers practical insights for achieving better performance than conventional designs.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Civil engineering (MU)

Grantor dc:publisher

University of Missouri--Columbia

Year dc:date.issued

2024

Author dc:creator

• White, Donald Andrew

Advisor dc:contributor.advisor

• Salim, Hani

Language dc:language.iso

eng, English

DOI

https://doi.org/10.32469/10355/108965

OAI identifier oai:identifier

oai:mospace.umsystem.edu:10355/108965