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Full-Text Articles in Social and Behavioral Sciences

Computational Simulation Of Eccentrically Loaded Circular Thin-Walled Concrete-Filled Double Steel Tubular Slender Columns, Mizan Ahmed, Qing Liang, Vipulkumar Patel, Muhammad N. S Hadi Jan 2020

Computational Simulation Of Eccentrically Loaded Circular Thin-Walled Concrete-Filled Double Steel Tubular Slender Columns, Mizan Ahmed, Qing Liang, Vipulkumar Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

The concrete confinement provided by the circular steel tubes improves the performance of circular concretefilled double steel tubular (CFDST) columns, which have increasingly been employed as high-performance structural members in tall buildings. This paper presents computational and design models for the simulation and design of high strength CFDST slender columns composed of circular thin-walled sections that are eccentrically loaded. The formulation of the computational model is described, which takes into account the influences of concrete confinement, geometric imperfection, second-order, gradual plasticity of steel, and geometric and material nonlinearities. The inverse quadratic method is implemented in computational algorithms which solve the …


Nonlinear Analysis Of Square Concrete-Filled Double Steel Tubular Slender Columns Incorporating Preload Effects, Mizan Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2020

Nonlinear Analysis Of Square Concrete-Filled Double Steel Tubular Slender Columns Incorporating Preload Effects, Mizan Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Thin-walled square and circular hollow steel tubes are designed to support the permanent and construction loads of several upper composite floors before filling the concrete into the tubes to form concrete-filled double steel tubular (CFDST) columns. The influences of preloads acting on the steel tubes on the structural responses of slender square CFDST columns have not been investigated either experimentally or numerically. This paper presents a fiber-based computational model for the determination of the interaction behavior of local and global buckling in axially and eccentrically loaded CFDST thin-walled square slender columns including preload effects. The computational modeling method accounts for …


Experimental And Numerical Investigations Of Eccentrically Loaded Rectangular Concrete-Filled Double Steel Tubular Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2020

Experimental And Numerical Investigations Of Eccentrically Loaded Rectangular Concrete-Filled Double Steel Tubular Columns, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Rectangular concrete-filled double steel tubular (CFDST) columns have increasingly been utilized in high-rise buildings to support heavy loads. However, the responses of eccentrically loaded rectangular CFDST short columns have rarely been studied. This paper reports experimental and numerical investigations into the behavior of rectangular thin-walled short CFDST columns composed of a rectangular inner steel tube loaded eccentrically. Tests on rectangular and square CFDST short columns under eccentric loading and axial loading were carried out to examine their responses to various design parameters, including the cross-sectional dimensions, loading eccentricity, and width-to-thickness ratios of the external and internal tubes. The experimental program …


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 …


Influence Of Particle Gradation And Shape On The Performance Of Stone Columns In Soft Clay, Firman Siahaan, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn, Ana Heitor Jan 2018

Influence Of Particle Gradation And Shape On The Performance Of Stone Columns In Soft Clay, Firman Siahaan, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn, Ana Heitor

Faculty of Engineering and Information Sciences - Papers: Part B

A stone column typically consists of particles whose influence has largely been overlooked in design practice in terms of stress transfer, pattern of deformation, and intrusion of fines (clogging). This article presents an experimental study on the load-deformation behavior of a model stone column installed in soft clay with a particular emphasis on the influence of particle gradation and shape under undrained loading. The results show that particle gradation and shape have a significant influence on the load-deformation behavior and the extent of fines intrusion into the stone columns. Relatively well-graded particle sizes favor the development of higher peak shear …


Load And Moment Interaction Diagram For Circular Concrete Columns Reinforced With Gfrp Bars And Gfrp Helices, Hogr Karim, M Neaz Sheikh, Muhammad N. S Hadi Jan 2017

Load And Moment Interaction Diagram For Circular Concrete Columns Reinforced With Gfrp Bars And Gfrp Helices, Hogr Karim, M Neaz Sheikh, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents analytical and experimental studies on the axial load-bending moment behavior of glass fiber-reinforced polymer (GFRP) bars and helices RC columns. The nominal axial load and bending moment of the columns were analyzed based on the stress-strain behavior of the cross-sectional components. A numerical integration method was used to determine the compressive force of concrete in the compression region. The analytical results were verified with experimental results of 12 circular specimens reinforced with GFRP bars and GFRP helices. Out of these 12 specimens, eight specimens were taken from available literature and four specimens were tested in this study. …


Nonlinear Analysis Of Circular High Strength Concrete-Filled Stainless Steel Tubular Slender Beam-Columns, Vipulkumar I. Patel, Qing Quan Liang, Muhammad N. S Hadi Jan 2017

Nonlinear Analysis Of Circular High Strength Concrete-Filled Stainless Steel Tubular Slender Beam-Columns, Vipulkumar I. Patel, Qing Quan Liang, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

Concrete-filled stainless steel tubular (CFSST) slender columns are increasingly used in composite structures owing to their distinguished features, such as aesthetic appearance, high corrosion resistance, high durability and ease of maintenance. Currently, however, there is a lack of an accurate and efficient numerical model that can be utilized to determine the performance of circular CFSST slender columns. This paper describes a nonlinear fiber-based model proposed for computing the deflection and axial load-moment strength interaction responses of eccentrically loaded circular high-strength CFSST slender columns. The fiber-based model incorporates the accurate three-stage stress-strain relations of stainless steels, accounting for different strain hardening …


Axial Load-Bending Moment Diagrams Of Gfrp Reinforced Columns And Gfrp Encased Square Columns, Jim Youssef, Muhammad N. S Hadi Jan 2017

Axial Load-Bending Moment Diagrams Of Gfrp Reinforced Columns And Gfrp Encased Square Columns, Jim Youssef, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

Fiber reinforced polymer (FRP) pultruded materials are available in a wide variety of shapes, including bars, I-sections, C-sections and other structural sections. Due to their high durability, low self-weight and reduced maintenance costs, these FRP materials are becoming a competitive option for replacing steel as structural materials especially in corrosive environments. This paper summarizes an experimental program on the axial and flexural behaviour of square concrete members reinforced with glass fiber reinforced polymer (GFRP) bars and embedded with pultruded GFRP structural sections under different loading conditions. Furthermore, an analytical model is presented to predict the axial load-bending moment interaction diagrams …


Behavior Of Self-Compacting Concrete Columns Reinforced Longitudinally With Steel Tubes, Muhammad N. S Hadi, Faez Alhussainy, M Neaz Sheikh Jan 2017

Behavior Of Self-Compacting Concrete Columns Reinforced Longitudinally With Steel Tubes, Muhammad N. S Hadi, Faez Alhussainy, M Neaz Sheikh

Faculty of Engineering and Information Sciences - Papers: Part B

This study investigates the behavior of self-compacting concrete (SCC) specimens reinforced with small-diameter steel tubes in lieu of reinforcing bars. Twenty specimens were cast and tested. Four specimens were reinforced with normal steel bars (reference specimens) and the remaining 16 with steel tubes. All specimens contained steel helices with a pitch of either 50 mm or 75 mm. Deformed steel bars of 16-mm diameter were used in the four reference specimens as longitudinal reinforcement. Steel tubes of 33.7-mm outside diameter with 2-mm wall thickness (ST33.7) and steel tubes of 26.9-mm outside diameter with 2.6-mm wall thickness (ST26.9) were used as …


Axial And Flexural Behavior Of Unreinforced And Frp Bar Reinforced Circular Concrete Filled Frp Tube Columns, Muhammad N. S Hadi, Qasim Khan, M Neaz Sheikh Jan 2016

Axial And Flexural Behavior Of Unreinforced And Frp Bar Reinforced Circular Concrete Filled Frp Tube Columns, Muhammad N. S Hadi, Qasim Khan, M Neaz Sheikh

Faculty of Engineering and Information Sciences - Papers: Part A

Fiber Reinforced Polymer (FRP) composites have emerged as a viable alternative of steel reinforcement due to higher ultimate tensile strength to weight ratio and corrosion resistance of FRP composites. Concrete Filled Fiber Reinforced Polymer Tube (CFFT) technique for new column construction has attracted significant research attention. This paper investigated the axial and flexural behavior of concrete filled Carbon FRP (CFRP) tube columns with and without CFRP bar and concrete filled Glass FRP (GFRP) tube columns with and without GFRP bar. The test results of 16 circular CFFT and four steel Reinforced Concrete (RC) specimens of 203-205 mm diameter and 800-812 …


Shape Optimisation Of Cold-Formed Steel Columns With Manufacturing Constraints Using The Hough Transform, Bin Wang, Benoit P. Gilbert, Adrien M. Molinier, Hong Guan, Lip H. Teh Jan 2016

Shape Optimisation Of Cold-Formed Steel Columns With Manufacturing Constraints Using The Hough Transform, Bin Wang, Benoit P. Gilbert, Adrien M. Molinier, Hong Guan, Lip H. Teh

Faculty of Engineering and Information Sciences - Papers: Part A

This paper introduces manufacturing constraints into a recently developed evolutionary algorithm for shape optimisation of CFS profiles. The algorithm is referred to as "self-shape optimisation" and uses Genetic Algorithm (GA) together with the Augmented Lagrangian (AL) method to avoid ill-conditioned problems. Simple manufacturing rules derived from the limitations of current cold-forming processes, i.e. a limited ability to form continuously curved surfaces without discrete bends, are described in the paper and incorporated into the algorithm. The Hough transform is used to detect straight lines and transform arbitrarily drawn cross-sections into manufacturable ones. Firstly, the algorithm is verified against a known optimisation …


Experimental Study On Frp Tube Reinforced Concrete Columns Under Different Loading Conditions, Weiqiang Wang, M Neaz Sheikh, Muhammad N. S Hadi Jan 2016

Experimental Study On Frp Tube Reinforced Concrete Columns Under Different Loading Conditions, Weiqiang Wang, M Neaz Sheikh, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

The behavior of fiber-reinforced polymer (FRP) tube reinforced concrete (FTRC) columns under different loading conditions was investigated in this study. Four groups of 16 specimens were cast and tested. Specimens in the first group (the reference group) were re- inforced with longitudinal steel bars and steel helices (Group REF). Specimens in the second group were reinforced with intact glass FRP tubes (Group IT). Specimens in the third group were also reinforced with intact glass FRP tubes. In addition, polymer grid was embedded into the concrete cover to reduce the cover spalling (Group ITG). Specimens in the fourth group were reinforced …


Cyclic Lateral Response Of Frp-Confined Circular Concrete-Filled Steel Tubular Columns, Tao Yu, Y M. Hu, Jin Guang Teng Jan 2016

Cyclic Lateral Response Of Frp-Confined Circular Concrete-Filled Steel Tubular Columns, Tao Yu, Y M. Hu, Jin Guang Teng

Faculty of Engineering and Information Sciences - Papers: Part A

Concrete-filled steel tubular (CFT) columns are widely used as columns in many structural systems and a common failure mode of such tubular columns is inelastic outward local buckling near a column end. The use of fibre-reinforced polymer (FRP) jackets/wraps for the suppression of such local buckling has recently been proposed and has been proven to possess excellent potential in both retrofit/strengthening and new construction. This paper presents the results of an experimental study into the behaviour of large-scale FRP-confined CFT (CCFT) columns under combined axial compression and lateral loading. The test parameters included the stiffness of the FRP jacket and …


Compressive Behavior Of Frp-Confined Concrete-Encased Steel Columns, Tao Yu, G Lin, Shi Shun Zhang Jan 2016

Compressive Behavior Of Frp-Confined Concrete-Encased Steel Columns, Tao Yu, G Lin, Shi Shun Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

FRP-confined concrete-encased steel I-section columns (FCSCs) are an emerging form of hybrid columns. An FCSC consists of an outer FRP tube, an encased steel section and a concrete infill. The FCSCs possess many advantages over conventional reinforced concrete columns, including the excellent corrosion resistance, excellent ductility and ease for construction. Existing studies on FCSCs, however, have been rather limited. This paper presents a combined experimental and theoretical study on the behavior of FCSCs under concentric and eccentric compression. The experimental program included the testing of a total of 14 specimens, with the main variables being the section configuration, the thickness …


Axial-Flexural Interactions Of Gfrp-Cfft Columns With And Without Reinforcing Gfrp Bars, Qasim S. Khan, M Neaz Sheikh, Muhammad N. S Hadi Jan 2016

Axial-Flexural Interactions Of Gfrp-Cfft Columns With And Without Reinforcing Gfrp Bars, Qasim S. Khan, M Neaz Sheikh, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

This study presents the results of an experimental program and analytical modeling for axial-flexural interactions of concrete-filled glass fiber-reinforced polymer tube (GFRP-CFFT) columns with and without reinforcing glass fiber-reinforced polymer (GFRP) bars. The experimental program included four steel RC specimens, four GFRP-CFFT specimens, and four GFRP bar-reinforced GFRP-CFFT specimens with an outer diameter of 205-206 mm and a height of 800-812 mm. The specimens were tested under concentric and 25- and 50-mm eccentric axial loads and four-point load. The experimental results showed that GFRP bar-reinforced GFRP-CFFT specimens sustained higher peak axial loads, axial and lateral deformations at peak axial load, …


Confinement Model For Frp Confined Normal- And High-Strength Concrete Circular Columns, Thong M. Pham, Muhammad N. S Hadi Jan 2014

Confinement Model For Frp Confined Normal- And High-Strength Concrete Circular Columns, Thong M. Pham, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

This study establishes a confinement model for FRP confined normal- and high-strength concrete circular columns. A new column parameter was suggested for estimating the compressive strength of FRP confined concrete. The proposed model is able to predict the ultimate condition of FRP confined concrete columns that have similar unconfined concrete strength and confining pressure but significant differences in the jacket stiffness. The proposed model was then verified using a database of 574 FRP confined concrete circular columns with different types of FRP. This database covers unconfined concrete strength between 15 MPa and 170 MPa and specimens with a diameter ranging …


Behaviour Of Gfrp Tube Reinforced Concrete Columns Under Axial Compression, Weiqiang Wang, M Neaz Sheikh, Muhammad N. S Hadi, Blake Lyons Jan 2014

Behaviour Of Gfrp Tube Reinforced Concrete Columns Under Axial Compression, Weiqiang Wang, M Neaz Sheikh, Muhammad N. S Hadi, Blake Lyons

Faculty of Engineering and Information Sciences - Papers: Part A

This paper reports the result of an experimental investigation on the behaviour of Glass Fibre Reinforced Polymer (GFRP) tube reinforced concrete columns under axial compression. The GFRP tube was placed into the concrete to provide reinforcement both in the longitudinal and transverse directions. In this study, a total of 8 columns with 150 mm diameter and 300 mm height were cast and tested under axial compression. The columns were divided into four groups and each group contains two identical columns. The first group had two columns of plain concrete, and the remaining three groups were reinforced with solid, axially perforated …


Spline-Shape Modification For Frp-Confined Concrete Columns: Theory And Evaluation, Muhammad N. S Hadi, Xu Lei Jan 2014

Spline-Shape Modification For Frp-Confined Concrete Columns: Theory And Evaluation, Muhammad N. S Hadi, Xu Lei

Faculty of Engineering and Information Sciences - Papers: Part A

The confinement efficiency for FRP-confined square concrete columns is relatively low compared to circular columns due to a large area of ineffectively-confined concrete and stress concentration at sharp corners. Shape modification of square concrete columns has been proposed but modifying the shape of cross-section from a square to a circle results in a significant increase in crosssectional area and self-weight of the columns, which raises new issues and is not practical when the space in the structure is limited. To address the abovementioned issues, a spline-shaped cross-section is proposed in this study as a target shape for shape modification. A …


Behaviour Of Hollow Core Square Reinforced Concrete Columns Wrapped With Cfrp With Different Fibre Orientations, Muhammad N. Hadi, T D. Le Jan 2014

Behaviour Of Hollow Core Square Reinforced Concrete Columns Wrapped With Cfrp With Different Fibre Orientations, Muhammad N. Hadi, T D. Le

Faculty of Engineering and Information Sciences - Papers: Part A

Results of testing twelve hollow core square reinforced concrete columns wrapped with Carbon fibre 33 reinforced polymer (CFRP) are presented. The effect of fibre orientation on the performance of specimens 34 under concentric and eccentric loads was investigated. Twelve specimens were divided into four groups with three 36 specimens each. The specimens in the first reference group were unwrapped, while the specimens in the 37 remaining groups were wrapped with CFRP of different wrap combinations of three fibre orientations.The specimens in each group were tested 39 under three eccentricities: 0 (concentric), 25, and 50 mm up to failure. Test results …


Numerical Analysis Of High-Strength Concrete-Filled Steel Tubular Slender Beam-Columns Under Cyclic Loading, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi Jan 2014

Numerical Analysis Of High-Strength Concrete-Filled Steel Tubular Slender Beam-Columns Under Cyclic Loading, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

The effects of cyclic local buckling on the behavior of concrete-filled steel tubular (CFST) slender beam-columns under cyclic loading were approximately considered in existing analytical methods by modifying the stress– strain curve for the steel tube in compression. These methods, however, cannot simulate the progressive cyclic local buckling of the steel tubes. This paper presents a new efficient numerical model for predicting the cyclic performance of high strength rectangular CFST slender beam-columns accounting for the effects of progressive cyclic local buckling of steel tube walls under stress gradients. Uniaxial cyclic constitutive laws for the concrete core and steel tubes are …


Nonlinear Analysis Of Axially Loaded Cicular Concrete-Filled Stainless Steel Tubular Short Columns, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi Jan 2014

Nonlinear Analysis Of Axially Loaded Cicular Concrete-Filled Stainless Steel Tubular Short Columns, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

The experiments indicate that stainless steels in tension deform plastically more than stainless steels in compression. Therefore, the strain hardening of stainless steels in compression is much faster than that of stainless steels in tension. The full-range two-stage constitutive model for stainless steels assumes that stainless steels follow the same stress-strain behavior in compression and tension, which may underestimate the compressive strength of stainless steel tubes. This paper presents a fiber element model incorporating the recently developed full-range three-stage stress-strain relationships based on experimentally observed behavior for stainless steels for the nonlinear analysis of circular concrete-filled stainless steel tubular (CFSST) …