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This study comprehensively investigates the self‐compacting alkali‐activated slag concrete‐filled cold‐formed steel tubes (SACFST) stub columns under axial compression. The innovative combination of alkali‐activated slag concrete (AASC) with concrete‐filled steel tubes (CFST) enhances both sustainability and structural performance. AASC, known for its eco‐friendly benefits compared to conventional concrete, was developed using industrial wastes, contributing to green construction practices. Based on Taguchi's L‐9 orthogonal array, nine mixes of self‐compacting alkali‐activated slag concrete (SASC) were developed, achieving impressive flowability exceeding 700 mm and compressive strengths ranging from 48 to 69 MPa. Additionally, split‐tensile strengths between 3.8 and 5.7 MPa, flexural strengths from 6.3 to 8.2 MPa, and a modulus of elasticity between 27.6 and 32.9 GPa were observed. Nine circular CFSTs containing SASC mixes were tested under axial compression, and a finite element model was developed to simulate their results. The experimental results were compared with standards from ACI 318, AIJ‐97, AISC‐360, AS 5100, and EC‐4, to evaluate the accuracy of axial capacity predictions. Among these standards, EC‐4 and AS 5100 provided the closest estimates, with mean PTest/PEC4 and PTest/P5100 ratios of 1.03 and 1.04, respectively, indicating a high level of accuracy. These findings highlight the potential of SACFST in advancing sustainable and resilient construction practices, laying the groundwork for future applications in structural engineering. [ABSTRACT FROM AUTHOR]

Abstract: An improved C0 two dimensional finite element model based on higher order zigzag plate theory (HOZT) is developed and applied to the analysis of laminated composite and sandwich plates under different situations to study the performance of the model. In the proposed model, the in-plane displacements variation is considered to be cubic for both the face sheets and the core, while the transverse displacement is assumed to vary quadratically within the core and remains constant in the faces beyond the core. It satisfies the conditions of transverse shear stress continuity at the layer interfaces as well as satisfies the zero transverse shear stress condition at the top and bottom of the plate. The well-known problem of continuity requirement of the derivatives of transverse displacements is overcome by choosing the nodal field variables in an efficient manner. A nine-node C0 quadratic plate finite element is implemented to model the HOZT for the present analysis. Numerical examples covering different features of laminated composite and sandwich plates are presented to illustrate the accuracy of the present model. [Copyright &y& Elsevier]

Abstract: Bending and free vibration behaviour of laminated soft core skew sandwich plate with stiff laminate face sheets is investigated using a recently developed C0 finite element (FE) model based on higher order zigzag theory (HOZT) in this paper. The in-plane displacement fields are assumed as a combination of a linear zigzag function with different slopes at each layer and a cubically varying function over the entire thickness. The out of plane displacement is considered to be quadratic within the core and constant in the face sheets. The plate theory ensures a shear stress-free condition at the top and bottom surfaces of the plate. Thus, the plate theory has all of the features required for accurate modelling of laminated skew sandwich plates. As very few element model based on this plate theory (HOZT) exist and they possess certain disadvantages, an attempt has been made to check the applicability of the refined element model. The nodal field variables are chosen in such a manner that there is no need to impose any penalty stiffness in the formulation. Refined C0 finite element model has been utilized to study some interesting problems on static and free vibration analysis of laminated skew sandwich plates. [Copyright &y& Elsevier]