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Full-Text Articles in Engineering
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
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 …
Geogrid-Confined Pervious Geopolymer Concrete Piles With Frp-Pvcconfined Concrete Core: Concept And Behaviour, Haiqiu Zhang, Muhammad N. S Hadi
Geogrid-Confined Pervious Geopolymer Concrete Piles With Frp-Pvcconfined Concrete Core: Concept And Behaviour, Haiqiu Zhang, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part B
The use of fibre reinforced polymer (FRP) and polyvinyl chloride (PVC) as strengthening materials for piles was found to be a promising scheme, due to their high strength-to-weight ratio, high durability and high anti-corrosion ability. This study presents an experimental investigation of a new form of composite piles: geogrid-confined pervious geopolymer concrete piles (GPGCPs) with fibre reinforced polymer (FRP)-polyvinyl chloride (PVC)-confined concrete core (FPCC). The GPGCP with FPCC consists of a circular geogrid outer tube, a FRP-PVC-confined normal geopolymer concrete core, and pervious geopolymer concrete (PGC) filled in between. The reason for applying PGC into piles is to increase the …
Investigation Of Engineering Properties Of Normal And High Strength Fly Ash Based Geopolymer And Alkali-Activated Slag Concrete Compared To Ordinary Portland Cement Concrete, Nabeel Farhan, M Neaz Sheikh, Muhammad N. S Hadi
Investigation Of Engineering Properties Of Normal And High Strength Fly Ash Based Geopolymer And Alkali-Activated Slag Concrete Compared To Ordinary Portland Cement Concrete, Nabeel Farhan, M Neaz Sheikh, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part B
Fly ash-based geopolymer (FAGP) and alkali-activated slag (AAS) concrete are produced by mixing alkaline solutions with aluminosilicate materials. As the FAGP and AAS concrete are free of Portland cement, they have a low carbon footprint and consume low energy during the production process. This paper compares the engineering properties of normal strength and high strength FAGP and AAS concrete with OPC concrete. The engineering properties considered in this study included workability, dry density, ultrasonic pulse velocity (UPV), compressive strength, indirect tensile strength, flexural strength, direct tensile strength, and stress-strain behaviour in compression and direct tension. Microstructural observations using scanning electronic …
Concrete Strength Reduction Due To Over Compaction, Ryan Howes, Muhammad N. S Hadi, Warren J. South
Concrete Strength Reduction Due To Over Compaction, Ryan Howes, Muhammad N. S Hadi, Warren J. South
Faculty of Engineering and Information Sciences - Papers: Part B
The purpose of this study was to evaluate the effect of over-compaction on the strength of concrete with regards to commercial and industry practices. Normal concrete, which is commonly used in construction was chosen. Samples were cast using a varying vibration time and testing was performed to determine concrete compressive strength, air content, density and a measure for segregation. These parameters were used to determine the relative sensitivity of concrete to under- versus over-compaction. If segregation was present, it was hypothesized the results would indicate a mathematical relationship between the segregation and strength reduction. This relationship would allow for determination …
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
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 …
Experimental Evaluation Of Tensile Strength Test Methods For Steel Fibre-Reinforced Concrete, Hussam A. Goaiz, Nabeel Farhan, M Neaz Sheikh, Tao Yu, Muhammad N. S Hadi
Experimental Evaluation Of Tensile Strength Test Methods For Steel Fibre-Reinforced Concrete, Hussam A. Goaiz, Nabeel Farhan, M Neaz Sheikh, Tao Yu, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part B
This study presents an experimental evaluation of three different methods for determining the tensile strength of steel fibre reinforced concrete (SFRC). The test methods include the splitting test (ST), double punch test (DPT) and direct tensile test (DTT). The compressive strength of the concrete used in this study ranged between 30 and 80 MPa with 0%, 1·5% and 3% steel fibre by volume of the concrete. In total, 81 concrete cylinders were cast and tested for 28-d compressive strength, splitting tensile strength and double punch tensile strength of the concrete. In addition, 27 concrete prism specimens were cast and tested …
Periodic Deprivation Of Gaseous Hydrogen Sulfide Affects The Activity Of The Concrete Corrosion Layer In Sewers, Xiaoyan Sun, Guangming Jiang, Philip Bond, Jurg Keller
Periodic Deprivation Of Gaseous Hydrogen Sulfide Affects The Activity Of The Concrete Corrosion Layer In Sewers, Xiaoyan Sun, Guangming Jiang, Philip Bond, Jurg Keller
Faculty of Engineering and Information Sciences - Papers: Part B
Sulfide induced concrete corrosion significantly reduces the service life of the sewer systems. Gaseoushydrogen sulfide (H2S) levels are a key factor affecting the corrosion rate and thesefluctuate due to thediurnalflow pattern of sewers. Currently, there is little known about how suchfluctuations, in particularthe periodic deprivation of H2S, may affect the corrosion activity. This study investigated the impact ofthe deprivation of H2S on the sulfide uptake rate (SUR) of concrete coupons incubated in laboratorycorrosion chambers. After systematic evaluation of the gaseous H2S concentration profiles of two sewersystems, two types of profiles, i.e. short- (1 h) and long- (12 h) term deprivation …
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
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 …
The Rapid Chemically Induced Corrosion Of Concrete Sewers At High H2s Concentration, Xuan Li, Liza O'Moore, Yarong Song, Philp Bond, Zhiguo Yuan, Simeon Wilkie, Lucija Hanzic, Guangming Jiang
The Rapid Chemically Induced Corrosion Of Concrete Sewers At High H2s Concentration, Xuan Li, Liza O'Moore, Yarong Song, Philp Bond, Zhiguo Yuan, Simeon Wilkie, Lucija Hanzic, Guangming Jiang
Faculty of Engineering and Information Sciences - Papers: Part B
Concrete corrosion in sewers is primarily caused by H2S in sewer atmosphere. H2S concentration can vary from several ppm to hundreds of ppm in real sewers. Our understanding of sewer corrosion has increased dramatically in recent years, however, there is limited knowledge of the concrete corrosion at high H2S levels. This study examined the corrosion development in sewers with high H2S concentrations. Fresh concrete coupons, manufactured according to sewer pipe standards, were exposed to corrosive conditions in a pilot-scale gravity sewer system with gaseous H2S at 1100 ± 100 ppm. The corrosion process was continuously monitored by measuring the surface …
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
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 …
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
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. …
Behavior Of Self-Compacting Concrete Columns Reinforced Longitudinally With Steel Tubes, Muhammad N. S Hadi, Faez Alhussainy, M Neaz Sheikh
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 …
Influence Of Geogrid On The Drying Shrinkage Performance Of Concrete Pavements, Abbas Sahib Abd-Ali Al-Hedad, Ebony Bambridge, Muhammad N. S Hadi
Influence Of Geogrid On The Drying Shrinkage Performance Of Concrete Pavements, Abbas Sahib Abd-Ali Al-Hedad, Ebony Bambridge, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part B
The aim of this study is to investigate the effect of geogrid on the drying shrinkage behaviour of concrete pavements. For this purpose, two categories of concrete specimens were prepared and tested by drying them within the controlled environmental conditions, for 56 days. The first category of specimens included casting and testing nine concrete prism specimens having dimensions of 75 x 75 x 280 mm. These specimens were divided into three groups. The first group included three unreinforced concrete prism specimens and taken as references. The second group consisted of three concrete prism specimens reinforced with a single biaxial geogrid …