Structural response of aluminium alloy concrete filled tubular columns

Abstract

There is an increasing trend of using structural aluminium within the construction industry, due to its superior mechanical properties, such as high strength‐to‐weight ratio and high resistance to corrosion. The use of aluminium combined with concrete can be advantageous in terms of the resultant structural capacity. Currently, the design standards for the structural use of aluminium are substantially conservative and less exhaustive, which limits the full exploitation of aluminium as a structural material. This paper aims at developing more reliable structural design specifications based on experimental testing of aluminium‐concrete composite columns. A series of specimens comprising concrete‐filled aluminium hollow sections were experimentally investigated. Square hollow sections and rectangular hollow sections with different aspect ratios were considered. The hollow sections employed 6082‐T6 aluminium alloy and were filled with concrete of C30 grade. The specimens were subjected to gradually increasing axial compressive loading until their failure. The behaviour of the specimens was observed through continuous monitoring and recording of the strain and displacement through instrumentation mounted on the specimens at critical locations. The experimentally obtained load capacities were compared to those predicted by European design specifications. Conclusions with regards to the structural efficiency of concrete‐filled aluminium alloy columns are drawn and design recommendations in line with the observed structural response are made.

Numerical modelling of concrete-filled aluminium alloy 6082-T6 columns under axial compression

“…The interaction properties between the concrete infill and the aluminium tube and material modelling of concrete were carefully considered. The obtained numerical results were verified against the experimental ones reported by [11]. A parametric study was carried out considering a wide variety of parameters such as the cross-sectional aspect ratio (h/b), slenderness and concrete strength.…”

“…The model aimed to simulate the non-linear behaviour of aluminium alloy square (SHS) and rectangular hollow sections (RHS), filled with concrete and subjected to gradually increased axial compressive loading. Recent experimental investigations on CFAT columns under axial compression performed by Georgantzia et al [11] were used to validate the FE model developed in this numerical study. In [11], a total of 10 members with pin-ended support conditions were tested.…”

“…Recent experimental investigations on CFAT columns under axial compression performed by Georgantzia et al [11] were used to validate the FE model developed in this numerical study. In [11], a total of 10 members with pin-ended support conditions were tested. The specimens comprised RHS and SHS and were fabricated by extrusion of 6082-T6 heat treated aluminium alloy.…”

“…All specimens failed due to flexural buckling around the minor axis. The measured material properties and dimensions of the specimens in [11] are summarised for reference in table 1, where Ea, fy and fck are the Young's Modulus of aluminium, the proof strength of aluminium and the compressive strength of concrete, respectively. The FE models developed in the first part of this study replicate the 10 specimens reported in [11].…”

“…The measured material properties and dimensions of the specimens in [11] are summarised for reference in table 1, where Ea, fy and fck are the Young's Modulus of aluminium, the proof strength of aluminium and the compressive strength of concrete, respectively. The FE models developed in the first part of this study replicate the 10 specimens reported in [11]. This section discusses key numerical modelling parameters such as element type and mesh, applied boundary conditions, initial geometric imperfections, material modelling and load application that will allow a successful validation of the FE model.…”