Design rules for aluminium sub-heads in facade systems
Author(s)
Akbari, Masomeh
Gunalan, Shanmuganathan
Gilbert, Benoit
Guan, Hong
Baleshan, Balesh
Year published
2020
Metadata
Show full item recordAbstract
Aluminium window wall frames are widely used in high-rise buildings as the building envelope to protect against environmental actions. However, the susceptibility of aluminum window wall frames to bearing failure under wind pressure is a subject of concern. The vertical members of window wall frames receive the wind load via the glass panels. Subsequently, this uniformly distributed load is transferred to the sub-heads at the end of the frames connected to the adjoining slab. Consequently, the sub-heads of window frames endure bearing failure due to the bending of the long cantilevered flange element. The structural behavior ...
View more >Aluminium window wall frames are widely used in high-rise buildings as the building envelope to protect against environmental actions. However, the susceptibility of aluminum window wall frames to bearing failure under wind pressure is a subject of concern. The vertical members of window wall frames receive the wind load via the glass panels. Subsequently, this uniformly distributed load is transferred to the sub-heads at the end of the frames connected to the adjoining slab. Consequently, the sub-heads of window frames endure bearing failure due to the bending of the long cantilevered flange element. The structural behavior of sub-head is similar to that of cold-formed steel tracks subjected to concentrated load by the stud in light gauge steel frame (LSF) walls. The AISI S240 2015, TI 809-07, and SSMA 2000 specifications provide design rules to predict the nominal cold formed steel stud-to-track connection strength in LSF walls. However, no design rule exists in the current aluminium standards to predict the bearing capacity of aluminium sub-heads. This oversight has necessitated the development of a set of design rules to predict the bearing capacity of aluminium subheads based on the bending of the flange. To achieve this goal, an experimental study was conducted to evaluate the bearing behavior of aluminum sub-heads subjected to concentrated load. The tests were performed using four different geometric sections under different bearing widths, loading positions, and boundary conditions. All specimens failed due to yielding at web-flange corner and the slipping of the bearing plate. Comparison of test results with the predictions from the aforementioned standards indicated that the available steel design rules are highly conservative for sub-head aluminium sections in window walls. Therefore, appropriate modifications were implemented in the existing design rules to predict the bearing capacities of aluminium sub-head sections with a high level of accuracy. This paper presents the details of the experimental study and the development of the new design rules.
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View more >Aluminium window wall frames are widely used in high-rise buildings as the building envelope to protect against environmental actions. However, the susceptibility of aluminum window wall frames to bearing failure under wind pressure is a subject of concern. The vertical members of window wall frames receive the wind load via the glass panels. Subsequently, this uniformly distributed load is transferred to the sub-heads at the end of the frames connected to the adjoining slab. Consequently, the sub-heads of window frames endure bearing failure due to the bending of the long cantilevered flange element. The structural behavior of sub-head is similar to that of cold-formed steel tracks subjected to concentrated load by the stud in light gauge steel frame (LSF) walls. The AISI S240 2015, TI 809-07, and SSMA 2000 specifications provide design rules to predict the nominal cold formed steel stud-to-track connection strength in LSF walls. However, no design rule exists in the current aluminium standards to predict the bearing capacity of aluminium sub-heads. This oversight has necessitated the development of a set of design rules to predict the bearing capacity of aluminium subheads based on the bending of the flange. To achieve this goal, an experimental study was conducted to evaluate the bearing behavior of aluminum sub-heads subjected to concentrated load. The tests were performed using four different geometric sections under different bearing widths, loading positions, and boundary conditions. All specimens failed due to yielding at web-flange corner and the slipping of the bearing plate. Comparison of test results with the predictions from the aforementioned standards indicated that the available steel design rules are highly conservative for sub-head aluminium sections in window walls. Therefore, appropriate modifications were implemented in the existing design rules to predict the bearing capacities of aluminium sub-head sections with a high level of accuracy. This paper presents the details of the experimental study and the development of the new design rules.
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Conference Title
Lecture Notes in Civil Engineering
Volume
37
Publisher URI
Subject
Civil engineering