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Full-Text Articles in Engineering
Information Processing As An Account Of Concrete Digital Computation, Nir Fresco
Information Processing As An Account Of Concrete Digital Computation, Nir Fresco
Faculty of Engineering and Information Sciences - Papers: Part A
It is common in cognitive science to equate computation (and in particular digital computation) with information processing. Yet, it is hard to find a comprehensive explicit account of concrete digital computation in information processing terms. An information processing account seems like a natural candidate to explain digital computation. But when 'information' comes under scrutiny, this account becomes a less obvious candidate. Four interpretations of information are examined here as the basis for an information processing account of digital computation, namely Shannon information, algorithmic information, factual information and instructional information. I argue that any plausible account of concrete computation has to …
A Methodology For Cost Optimization Of The Layout Design Of Multi-Span Reinforced Concrete Beams, Pezhman Sharafi, Muhammad Hadi, Lip H. Teh
A Methodology For Cost Optimization Of The Layout Design Of Multi-Span Reinforced Concrete Beams, Pezhman Sharafi, Muhammad Hadi, Lip H. Teh
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a description of a new methodology for the optimum preliminary layout design of reinforced concrete multi-span beams considering the relevant cost elements. First, a new objective function is presented, as an alternative to traditional cost functions for reinforced concrete beams. The ability of being easily employed in layout optimization problems, gives the new cost function a distinct advantage over its alternatives. Examples are included to illustrate the performance of the new methodology.
Response Of Substandard Reinforcing Details T Connections Upgraded With Concrete Covers And Cfrp, Tung M. Tran, B Matuszkiewicz, Muhammad N. S Hadi
Response Of Substandard Reinforcing Details T Connections Upgraded With Concrete Covers And Cfrp, Tung M. Tran, B Matuszkiewicz, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part A
This paper introduces the responses of two substandard reinforcing details exterior beam-column T connections, which were upgraded by a new retrofitting method using concrete covers and carbon fiber reinforced polymer (CFRP). Two reinforced concrete (RC) exterior beam-column connections without transverse reinforcement at the joints were cast and tested. A mix of epoxy resin and 20% thickener was used to glue the first connection (the Strengthened specimen, TS) with the concrete covers around the column at the joint area to modify it from a square to a circular section and then it was wrapped with CFRP to strengthen. A load was …
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
Faculty of Engineering and Information Sciences - Papers: Part A
In conventional steel-concrete-steel (SCS) construction, the external steel plates are connected to the concrete infill by welded shear stud connectors. This paper describes a programme of experimental and numerical investigations on reduced-scale non-composite SCS panels with axially restrained connections. The experimental results have demonstrated that the non-composite SCS panels are capable of developing enhanced load-carrying capacity through the tensile membrane resistance of the steel faceplates. This type of construction was found to exhibit highly ductile response and be able to sustain large end rotations of up to 18° without collapse. High fidelity finite element models for SCS panels under impact …
Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns With A Square Outer Tube And A Circular Innert Tube Subjected To Axial Compression, Tao Yu, J G. Teng
Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns With A Square Outer Tube And A Circular Innert Tube Subjected To Axial Compression, Tao Yu, J G. Teng
Faculty of Engineering and Information Sciences - Papers: Part A
Hybrid fiber-reinforced polymer (FRP) concrete steel, double skin tubular columns (DSTCs) are a new form of hybrid columns. The most common sectional form of hybrid DSTCs consists of a layer of concrete sandwiched between a circular inner steel tube and a circular outer FRP tube whose fiber directions are close to the hoop detection to provide effective confinement to the concrete. Much recent research has been conducted on circular hybrid DSTCs, which has demonstrated that the combination of the three constituent materials leads to several advantages not available with existing forms of columns. In practical applications, for aesthetic and other …
Drying Shrinkage Of Concrete Made From Recycled Concrete Aggregate, B A. Whiting, T J. Mccarthy, E Lume
Drying Shrinkage Of Concrete Made From Recycled Concrete Aggregate, B A. Whiting, T J. Mccarthy, E Lume
Faculty of Engineering and Information Sciences - Papers: Part A
Recycled concrete aggregates (RCA) are used in new concrete mixes, termed recycled aggregate concrete (RAC). Among losses in most fresh and hardened properties, literature reports that RAC suffers increased levels of drying shrinkage compared to equivalent mixes incorporating conventional aggregates. This paper describes the procedure and results of a range of experiments conducted on a commercial RCA and its use in new concrete mixes. In particular, this work quantifies the effect 100% RCA has on the drying shrinkage of the resulting concrete. A commercially available RCA was characterised by analysing the particle shape and texture, percentage of solid contaminants, particle …
Nonlinear Analysis Of Biaxially Loaded High Strength Rectangular Concrete-Filled Steel Tubular Slender Beam-Columns, Part I: Theory, Qing Quan Liang, Vipulkumar Ishvarbhai Patel, Muhammad N. S Hadi
Nonlinear Analysis Of Biaxially Loaded High Strength Rectangular Concrete-Filled Steel Tubular Slender Beam-Columns, Part I: Theory, Qing Quan Liang, Vipulkumar Ishvarbhai Patel, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a new numerical model for the nonlinear inelastic analysis of biaxially loaded high strength thin-walled rectangular concrete-filled steel tubular (CFST) slender beam-columns. The numerical model considers the effects of progressive local buckling, initial geometric imperfections, high strength materials and second order. The accurate fiber element method is used to model the inelastic behavior of composite cross-sections. Theoretical models are developed that simulate the load-deflection responses and strength envelopes of thin-walled rectangular CFST slender beamcolumns under biaxial loads. New computational algorithms based on the M ller's method are developed to adjust the depth and orientation of the neutral …
Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns: Cyclic Axial Compression Tests, Tao Yu, Yu-Bo Cao, Bing Zhang, J G. Teng
Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns: Cyclic Axial Compression Tests, Tao Yu, Yu-Bo Cao, Bing Zhang, J G. Teng
Faculty of Engineering and Information Sciences - Papers: Part A
Hybrid FRP-concrete-steel double-skin tubular columns (hybrid DSTCs) are a new form of hybrid columns recently developed at The Hong Kong Polytechnic University. A hybrid DSTC consists of an inner steel tube, an outer FRP tube and a concrete infill between the two tubes. Hybrid DSTCs possess many important advantages over existing column forms, including their excellent corrosion resistance and excellent seismic resistance. While a large amount of research has been conducted on the monotonic behavior of this novel form of columns, only a limited amount of work has been conducted on their behavior under cyclic loading. This paper presents the …
Utilising Non-Composite Steel-Concrete-Steel Panels For Protective Structures, A M. Remennikov, S Y. Kong, Brian Uy
Utilising Non-Composite Steel-Concrete-Steel Panels For Protective Structures, A M. Remennikov, S Y. Kong, Brian Uy
Faculty of Engineering and Information Sciences - Papers: Part A
A high-performance protective structure utilising non-composite steel-concrete-steel (SCS) sandwich panels for protecting buildings and facilities against close-range detonation of VBIEDs and heavy ve-hicle impacts has been developed. Unlike other existing composite sandwich panels, no shear connec-tors between the steel faceplates are utilised to construct protective panels in order to simplify the con-struction process. The concrete core of the panel is included to provide the mass for increased inertia effects, and the steel faceplates are designed to develop tensile membrane resistance at large displace-ment to dissipate impulsive energy. The energy dissipation capability and high ductility of the axially-restrained non-composite SCS panels …
Non-Uniform Stress Distribution In Frp-Wrapped Circular Concrete Columns Under Uniform Axial Deformation, S Q. Li, J F. Chen, Tao Yu, J G. Teng
Non-Uniform Stress Distribution In Frp-Wrapped Circular Concrete Columns Under Uniform Axial Deformation, S Q. Li, J F. Chen, Tao Yu, J G. Teng
Faculty of Engineering and Information Sciences - Papers: Part A
The confinement of concrete columns using bonded FRP wraps has become a popular retrofit technique. Through extensive research in the last two decades, many stress-strain models have been developed for concrete in FRP-wrapped circular columns. All these models assume that the stress state is axisymmetric in an FRP-wrapped circular concrete column under concentric axial compression. This implies that the FRP wrap is assumed to be axisymmetric in geometry, but in reality such axisymmetry is not realised due to the existence of an overlapping zone. This paper presents a finite element investigation into the stress state in FRP-wrapped circular concrete columns …
Reliability-Based Conversion Of A Structural Design Code For Railway Prestressed Concrete Sleepers, A M. Remennikov, Martin Murray, Sakdirat Kaewunruen
Reliability-Based Conversion Of A Structural Design Code For Railway Prestressed Concrete Sleepers, A M. Remennikov, Martin Murray, Sakdirat Kaewunruen
Faculty of Engineering and Information Sciences - Papers: Part A
"Ballasted railway track is very suitable for heavy-rail networks because of its many superior advantages in design, construction, short- and long-term maintenance, sustainability, and life cycle cost. An important part of the railway track system, which distributes the wheel load to the formation, is the railway sleeper. Improved knowledge has raised concerns about design techniques for prestressed concrete (PC) sleepers. Most current design codes for these rely on allowable stresses and material strength reductions. However, premature cracking of PC sleepers has been found in railway tracks. The major cause of cracking is the infrequent but high-magnitude wheel loads produced by …
Nonlinear Inelastic Behavior Of Circular Concrete-Filled Steel Tubular Slender Beam-Columns With Preload Effects, Vipulkumar Ishvarbhai Patel, Qing Quan Liang, Muhammad N. Hadi
Nonlinear Inelastic Behavior Of Circular Concrete-Filled Steel Tubular Slender Beam-Columns With Preload Effects, Vipulkumar Ishvarbhai Patel, Qing Quan Liang, Muhammad N. Hadi
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a numerical model based on fiber element formulations for simulating the nonlinear inelastic behavior of eccentrically loaded circular concrete-filled steel tubular (CFST) slender beam-columns with preload effects. Deflections caused by preloads are included in the global analysis of CFST slender beam-columns as initial geometric imperfections. Computational algorithms based on the Müller's method are developed to obtain load-deflection responses of CFST slender beam-columns including preload effects. The accuracy of the numerical model is examined by comparisons of computer solutions with experimental results. The numerical model is utilized to investigate the effects of preloads on the axial load-deflection curves, …
Concrete Digital Computation: What Does It Take For A Physical System To Compute?, Nir Fresco
Concrete Digital Computation: What Does It Take For A Physical System To Compute?, Nir Fresco
Faculty of Engineering and Information Sciences - Papers: Part A
This paper deals with the question: what are the key requirements for a physical system to perform digital computation? Time and again cognitive scientists are quick to employ the notion of computation simpliciter when asserting basically that cognitive activities are computational. They employ this notion as if there was or is a consensus on just what it takes for a physical system to perform computation, and in particular digital computation. Some cognitive scientists in referring to digital computation simply adhere to Turing's notion of computability. Classical computability theory studies what functions on the natural numbers are computable and what mathematical …
Axial Compression Tests On Frp-Jacketed Circular Concrete-Filled Thin Steel Tubes, Y M. Hu, T Yu, J G. Teng
Axial Compression Tests On Frp-Jacketed Circular Concrete-Filled Thin Steel Tubes, Y M. Hu, T Yu, J G. Teng
Faculty of Engineering and Information Sciences - Papers: Part A
Fibre-reinforced polymer (FRP) jackets have been widely used to confine concrete columns to enhance their load-carrying capacity and ductility. More recently, the use of FRP jackets to improve the performance of hollow steel tubes and concrete-filled steel tubes has also been explored. This paper presents the results of a recent experimental study in which the behaviour of FRP-confined circular concrete-filled thin steel tubes under axial compression was examined. The experimental study included three series of tests and was focussed on the effects of the diameter-to-thickness ratio of the steel tube and the confinement stiffness of the FRP jacket. The test …
Assessment Of Drucker-Prager Type Plasticity Models For Predicting The Behaviour Of Frp-Confined Concrete, T Yu, J G. Teng, Y L. Wong, S L. Dong
Assessment Of Drucker-Prager Type Plasticity Models For Predicting The Behaviour Of Frp-Confined Concrete, T Yu, J G. Teng, Y L. Wong, S L. Dong
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a critical assessment of the ability of existing Drucker-Prager (D-P) type plasticity models to predict the behaviour of confined concrete using both experimental observations and a recent analytical model. This assessment shows that for a D-P plasticity model to succeed in predicting the behaviour of FRP-confined and other passively-confined concrete, it needs to possess the following three features: (a) a yield criterion which includes the third deviatoric stress invariant, (b) a hardening/softening rule which is dependent on the confining pressure; and (c) a flow rule which is dependent on both the confining pressure and the rate of …
Flexural Behaviour Of Hybrid Frp-Concrete-Steel Double Skin Tubular Members, T Yu, Y L. Wong, J G. Teng, S L. Dong, E S.S Lam
Flexural Behaviour Of Hybrid Frp-Concrete-Steel Double Skin Tubular Members, T Yu, Y L. Wong, J G. Teng, S L. Dong, E S.S Lam
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents the results of an experimental study on the flexural behavior of a new type of hybrid FRP-concrete-steel member as well as results from a corresponding theoretical model based on the plane section assumption and the fiber element approach. This new type of hybrid member is in the form of a double-skin tube, composed of a steel inner tube and an FRP outer tube with a concrete infill between the two tubes, and may be employed as columns or beams. The parameters examined in this study include the section configuration, the concrete strength, and the thicknesses of the …