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Social and Behavioral Sciences Commons

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2019

Science and Technology Studies

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Full-Text Articles in Social and Behavioral Sciences

Performance Evaluation Of Intermittently Cfrp Wrapped Square And Circularised Square Reinforced Concrete Columns Under Different Loading Conditions, Anh Duc Mai, M Neaz Sheikh, Muhammad N. S Hadi Jan 2019

Performance Evaluation Of Intermittently Cfrp Wrapped Square And Circularised Square Reinforced Concrete Columns Under Different Loading Conditions, Anh Duc Mai, M Neaz Sheikh, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents the results of an experimental investigation on square and circularised square rein-forced concrete (RC) columns intermittently wrapped with carbon fibre reinforced polymer (CFRP)under different loading conditions. Twelve RC specimens consisting of eight square RC specimenswith 150mm150mm cross-section and 800mm height and four circularised square RC specimenswith 212mm diameter and 800 mm height were tested under concentric axial load, eccentric axialload and four-point flexural load. The test results showed that intermittent wrapping increased thestrength and ductility of square RC specimens. The test results also showed that circularisation com-bined with intermittent wrapping significantly improved the strength and ductility of …


Experimental And Numerical Studies Of Square Concrete-Filled Double Steel Tubular Short Columns Under Eccentric Loading, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2019

Experimental And Numerical Studies Of Square Concrete-Filled Double Steel Tubular Short Columns Under Eccentric Loading, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Square concrete-filled double steel tubular (CFDST) beam-columns consisting of an internal circular steel tube have increasingly been utilized in composite building structures because of their high structural performance. This paper describes experimental and numerical studies on the structural responses of square thin-walled CFDST columns loaded eccentrically. Tests on twenty short square CFDST columns were undertaken that included sixteen columns under eccentric loading and four columns under concentric loading. The parameters examined in the experiments included the cross-sectional dimensions, the width-to-thickness ratios of outer and internal tubes and loading eccentricity. The measured ultimate strengths, load-shortening responses, load-lateral displacement curves, stress-strain curves …


Numerical Analysis Of Axially Loaded Rectangular Concrete-Filled Steel Tubular Short Columns At Elevated Temperatures, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi Jan 2019

Numerical Analysis Of Axially Loaded Rectangular Concrete-Filled Steel Tubular Short Columns At Elevated Temperatures, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Elevated temperatures significantly reduce the local buckling strengths of steel tubes and the ultimate strengths of rectangular concrete-filled steel tubular (CFST) columns exposed to fire. No fiber-based models have been developed that include local buckling effects on the fire-resistance of rectangular CFST columns. This paper presents a new fiber element model for the fire-resistance predictions of axially loaded rectangular CFST short columns at elevated temperatures considering local buckling. The thermal analysis problem of a CFST column is solved by the finite difference method to determine the temperature distribution within its cross-section including an air gap, concrete moisture content and the …


Numerical Analysis Of Axially Loaded Circular High Strength Concrete-Filled Double Steel Tubular Short Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2019

Numerical Analysis Of Axially Loaded Circular High Strength Concrete-Filled Double Steel Tubular Short Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Circular high-strength concrete-filled double steel tubular (CFDST) columns are high performance members where the internal and external steel tubes offer significant confinement to the concrete infill. The confinement remarkably improves the concrete compressive strength and ductility. However, no fiber element models have been formulated for computing the responses of CFDST columns with circular steel tubes filled with high-strength concrete incorporating accurate confinement to the core and sandwiched concrete. In this paper, a new fiber-based numerical model is developed that computes the axial load-strain responses of circular high-strength CFDST short columns under axial loading. Based on existing experimental results, a new …


Maximum Axial Load Carrying Capacity Of Fibre Reinforced-Polymer (Frp) Bar Reinforced Concrete Columns Under Axial Compression, Hayder Alaa Hasan, M Neaz Sheikh, Muhammad N. S Hadi Jan 2019

Maximum Axial Load Carrying Capacity Of Fibre Reinforced-Polymer (Frp) Bar Reinforced Concrete Columns Under Axial Compression, Hayder Alaa Hasan, M Neaz Sheikh, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

In this study, a new equation is proposed to compute the maximum axial load carrying capacity of FRP bar reinforced concrete columns under axial compression. The equation proposed in this study was critically compared with the equations proposed in the previous research studies using a wide range of experimental data taken from the available literature. In general, it was found that computing the contribution of the FRP longitudinal bars in concrete columns based on the modulus of elasticity (stiffness) of the FRP bars provides more rational predictions than computing the contribution of the FRP longitudinal bars based on the ultimate …


Axial-Flexural Interaction Diagram Of Rpc Columns Reinforced With Steel Fibres, Ahmed Al-Tikrite, Muhammad N. S Hadi Jan 2019

Axial-Flexural Interaction Diagram Of Rpc Columns Reinforced With Steel Fibres, Ahmed Al-Tikrite, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents analytical modelling of the axial-flexural behaviour of Reactive Powder Concrete (RPC) columns reinforced with and without steel fibres of different types (industrial and waste) in individual and hybrid forms. An analytical stress-strain model for unconfined RPC was used for the analysis of the axial loads and bending moments of the fibrous RPC columns. The layer-by-layer numerical integration method was used to calculate the axial load and bending moments in this study. The analytically developed axial load-bending moment ( P-M ) interaction diagrams were validated by using experimental results from the literature. A para- metric study was carried …


New Technique For Strengthening Squarereinforced Concrete Columns By The Circularisation With Reactive Powder Concrete And Wrapping With Fibre-Reinforced Polymer, Atheer Hilal Mahdi Al - Gburi, M Neaz Sheikh, Muhammad N. S Hadi Jan 2019

New Technique For Strengthening Squarereinforced Concrete Columns By The Circularisation With Reactive Powder Concrete And Wrapping With Fibre-Reinforced Polymer, Atheer Hilal Mahdi Al - Gburi, M Neaz Sheikh, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents a new strengthening technique for square-reinforced concrete (RC) columns by circularisation with reactive powder concrete (RPC) and wrapping with fibre-reinforced polymer (FRP). RC column specimens were tested, divided into four groups of four specimens based on the strengthening technique: four reference square specimens (150mm side length) without any strengthening, four were wrapped with two layers of carbon fibre-reinforced polymer (CFRP) and the remaining eight were strengthened by changing the square cross-section to a 240mm diameter circle with RPC jacket. Four of the RPC jacketed specimens were left unwrapped, while the last four were wrapped with two layers …


Fiber Element Simulation Of Interaction Behavior Of Local And Global Buckling In Axially Loaded Rectangular Concrete-Filled Steel Tubular Slender Columns Under Fire Exposure, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi Jan 2019

Fiber Element Simulation Of Interaction Behavior Of Local And Global Buckling In Axially Loaded Rectangular Concrete-Filled Steel Tubular Slender Columns Under Fire Exposure, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Slender rectangular thin-walled concrete-filled steel tubular (CFST) columns in composite building structures exposed to fire may experience the interaction of local and global buckling. Numerical investigations on the interaction buckling responses of such columns under fire exposure have been rarely reported. This paper describes a fiber-based computational model for the prediction of the fire-resistance and interaction responses of local and global buckling of concentrically-loaded slender CFST columns made of rectangular sections exposed to fire. The thermal analysis is undertaken to calculate the distribution of temperatures in the column cross-section considering the effects of the air gap between concrete and steel, …


Nonlinear Post-Fire Simulation Of Concentrically Loaded Rectangular Thin-Walled Concrete-Filled Steel Tubular Short Columns Accounting For Progressive Local Buckling, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi Jan 2019

Nonlinear Post-Fire Simulation Of Concentrically Loaded Rectangular Thin-Walled Concrete-Filled Steel Tubular Short Columns Accounting For Progressive Local Buckling, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

The repair of fire-damaged thin-walled rectangular concrete-filled steel tubular (CFST) columns in engineering structures after fire exposure requires the assessment of their residual strength and stiffness. Existing numerical models have not accounted for the effects of local buckling on the post-fire behavior of CFST columns with rectangular thin-walled sections. This paper describes a nonlinear post-fire simulation technique underlying the theory of fiber analysis for determining the residual strengths and post-fire responses of concentrically loaded short thin-walled rectangular CFST columns accounting for progressive local buckling. The post-fire stress-strain laws for concrete in rectangular CFST columns are proposed based on available test …


Behavior Of Eccentrically Loaded Double Circular Steel Tubular Short Columns Filled With Concrete, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2019

Behavior Of Eccentrically Loaded Double Circular Steel Tubular Short Columns Filled With Concrete, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Circular concrete-filled double steel tubular (CFDST) columns in high-rise building structures possess high ductility and strength performance owing to the concrete confinement exerted by the external and internal circular steel tubes. However, the behavior of circular CFDST short columns that are loaded eccentrically has not been investigated either experimentally or numerically. Particularly, numerical studies on the moment-curvature responses, strength envelopes, confinement effects and moment distributions in circular CFDST beam-columns have not been reported. In this paper, experimental and computational investigations into the structural responses of circular CFDST short columns loaded eccentrically are presented. Nineteen short circular CFDST columns with various …