Abstract
A through-railway bridge with an inclined girder has recently been applied to optimize the cross-section of a slender
bridge structure in railway bridges. To achieve the additional cross-section optimization effect by the bolted end-plate
connection, it is necessary to investigate the application of the bolted end-plate tension connection between the inclined girder
and the crossbeam. This basic study was conducted on the application of the bolted end-plate moment connection of crossbeams
to half-through girders with inclined webs. The combined behavior of vertical deflection and rotational behavior was observed
due to the effect of the web inclination in the inclined girder where the steel crossbeam was connected to the girder by the bolted
end-plate moment connection. Therefore, in the experiment, the deflection of the inclined girder was 1.77–2.93 times greater
than that of the vertical girder but the lateral deflection of the inclined girder was 0.4 times less than that of the vertical girder.
Moreover, the tensile stress of the upper bolts in the inclined girder with low crossbeams was clearly 0.81 times lower than that
of the vertical girder. According to the results, the design formula for vertical girders does not reflect the influence of the web
inclination. Therefore, this study proposed the design procedures for the inclined girder to apply the bolted end-plate moment
connection of the crossbeam to the inclined girder by reflecting the design change factors according to the effect of the web
inclination.
Key Words
bolted end-plate moment connection; fatigue of tensile bolt; half-through railway bridge; inclined web;
lateral torsional buckling
Address
Jung Hyun Kim and Chang Su Shim:Jung Hyun Kim and Chang Su Shim
Abstract
In the realm of nanotechnology, the nonlocal strain gradient theory takes center stage as it scrutinizes the behavior of
spinning cantilever nanobeams and nanotubes, pivotal components supporting various mechanical movements in sport
structures. The dynamics of these structures have sparked debates within the scientific community, with some contending that
nonlocal cantilever models fail to predict dynamic softening, while others propose that they can indeed exhibit stiffness
softening characteristics. To address these disparities, this paper investigates the dynamic response of a nonlocal cantilever
cylindrical beam under the influence of external discontinuous dynamic loads. The study employs four distinct models: the
Euler-Bernoulli beam model, Timoshenko beam model, higher-order beam model, and a novel higher-order tube model. These
models account for the effects of functionally graded materials (FGMs) in the radial tube direction, giving rise to nanotubes with
varying properties. The Hamilton principle is employed to formulate the governing differential equations and precise boundary
conditions. These equations are subsequently solved using the generalized differential quadrature element technique (GDQEM).
This research not only advances our understanding of the dynamic behavior of nanotubes but also reveals the intriguing
phenomena of both hardening and softening in the nonlocal parameter within cantilever nanostructures. Moreover, the findings
hold promise for practical applications, including drug delivery, where the controlled vibrations of nanotubes can enhance the
precision and efficiency of medication transport within the human body. By exploring the multifaceted characteristics of
nanotubes, this study not only contributes to the design and manufacturing of rotating nanostructures but also offers insights into
their potential role in revolutionizing drug delivery systems.
Key Words
blood flow; drug delivery; nanodevices; nanotube; rotational motion; stability performance
Address
Shaopeng Song:Sports Center, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
Tao Zhang:College of Physical Education, Shaanxi University of Technology, Hanzhong, 723001, Shannxi, China
Zhiewn Zhui:Center of excellence in design and manufacturing, Tehran, Iran
Abstract
In the current examination, a trigonometric shear deformation theory is hired to govern natural frequencies of a
functionally graded porous microplate which is covered by two nanocomposite layers. The properties of the structure are varied
based on the specified patterns. Utilizing the modified form of couple stress theory for taking the scale effect into account in
conjunction with Hamilton's principle, the motion equations are obtained. Then, they are solved via Fourier series functions as
an analytical approach. After confirming the results' accuracy, various parameters' effect on the results is investigated. Designing
and manufacturing more efficient structures, especially those that are subjected to multi-physical loads can be accounted as
findings of this work.
Abstract
Tower structures have been widely used in communication and transmission engineering. The failure of joints is the
leading cause of structure failure, which make it play a crucial role in tower structure engineering. In this study, the aluminum
alloy three tube tower structure is taken as the prototype, and the middle joint of the tower was selected as the research object.
Three different stainless steel-aluminum alloy composite joints (SACJs), denoted by TA, TB and TC, were designed. Finite
element (FE) modeling analysis was used to compare and determine the TC joint as the best solution. Detail requirements of
fasteners in the TC stainless steel-aluminum alloy composite joint (TC-SACJ) were designed and verified. In order to
systematically and comprehensively study the mechanical properties of TC-SACJ under multi-directional loading conditions, the
full-scale experiments and FE simulation models were all performed for mechanical response analysis. The failure modes, loadcarrying capacities, and axial load versus displacement/stain testing curves of all full-scale specimens under tension/compression
loading conditions were obtained. The results show that the maximum vertical displacement of aluminum alloy tube is 26.9mm,
and the maximum lateral displacement of TC-SACJs is 1.0 mm. In general, the TC-SACJs are in an elastic state under the
design load, which meet the design requirements and has a good safety reserve. This work can provide references for the design
and engineering application of aluminum alloy tower structures.
Key Words
aluminum alloy tower structure; finite element modeling; full-scale experiment; stainless steel-aluminum
alloy joint; ultimate bearing capacity
Address
Yingying Zhang, Qiu Yu, Wei Song, Junhao Xu, Yushuai Zhao and Baorui Sun:Jiangsu Key Laboratory of Environmental Impact and Structural Safety in Engineering, State Key Laboratory for Geomechanics and Deep
Underground Engineering, Jiangsu Collaborative Innovation Center for Building Energy Saving and Construction Technology, China
University of Mining and Technology, Daxue Road No. 1 Tongshan District Xuzhou Jiangsu Province, China
Abstract
Cost-effective solutions provided by composite construction are gaining popularity which, in turn, promotes the
appearance on the market of new types of composite sections that allow not only to take advantage of the synergy of steel and
concrete working together at room temperature, but also to improve their behaviour at high temperatures. When combined with
high performance materials, significant load-bearing capacities can be achieved even with reduced cross-sectional dimensions.
Steel-reinforced concrete-filled steel tubular (SR-CFST) columns are one of these innovative composite sections, where an open
steel profile is embedded into a CFST section. Besides the renowned benefits of these typologies at room temperature, the fire
protection offered by the surrounding concrete to the inner steel profile, gives them an enhanced fire performance which delays
its loss of mechanical capacity in a fire scenario. The experimental evidence on the fire behaviour of SR-CFST columns is still
scarce, particularly when combined with high performance materials. However, it is being much needed for the development of
specific design provisions that consider the use of the inner steel profile in CFST columns. In this work, a new experimental
program on the thermo-mechanical behaviour of SR-CFST columns is presented to extend the available experimental database.
Ten SR-CFST stub columns, with circular and square geometries, combining high strength steel and concrete were tested. It was
seen that the circular specimens reached higher failure times than the square columns, with the failure time increasing both when
high strength steel was used at the embedded steel profile and high strength concrete was used as infill. Finally, different
proposals for the reduction coefficients of high performance materials were assessed in the prediction of the cross-sectional fire
resistance of the SR-CFST columns.
Key Words
concrete-filled steel tubular columns; embedded steel profile; fire reduction factors; fire resistance; high
strength concrete; high strength steel
Address
David Medall, Carmen Ibanez, Ana Espinos and Manuel L. Romero:ICITECH, Universitat Politècnica de València, Valencia, Spain
Abstract
In the present work, a comparative study has been carried out between power, exponential, and sigmoidal sandwich
FGM plates for free vibration conditions under hygro-thermal conditions. Rules of mixture is used to determine effective
material properties across the thickness for power-law and sigmoid sandwich FGM plates. Exponential law is used to plot
effective material properties for exponentially graded sandwich FGM plates. Temperature and moisture dependent material
properties were used during the analysis. Free vibration analysis is carried out using recently proposed finite element based
HOZT. Present formulation satisfies interlayer transverse stress continuity conditions at interfaces and transverse shear stressfree conditions at the plate's top and bottom surfaces. The present model is free from any penalty or post-processing
requirements. Several new results are reported in the present work, especially for unsymmetric sandwich FGM plates and
exponential and sigmoidal sandwich FGM plates.
Address
Aman Garg: State Key Laboratory of Intelligent Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
Neeraj Kumar Shukla: Department of Electrical Engineering, College of Engineering, King Khalid University, Abha-62314, Kingdom of Saudi Arabia
M. Ramkumar Raja: Department of Electrical Engineering, College of Engineering, King Khalid University, Abha-62314, Kingdom of Saudi Arabia
Hanuman D. Chalak: Department of Civil Engineering, National Institute of Technology Kurukshetra, Haryana, India – 136119
Mohamed-Ouejdi Belarbi: 1)Laboratoire de recherche en Génie Civil, LRGC, Université de Biskra. B.P.145, R.P.7000, Biskra, Algeria 2)School of Engineering, Lebanese American University, Byblos, Lebanon
Abdelouahed Tounsi: 1)YFL (Yonsei Frontier Lab), Yonsei University, Seoul, Korea 2)Department of Civil and Environmental Engineering, King Fahd University of Petroleum &Minerals, 31261 Dhahran, Eastern Province, Saudi Arabia 3)Material and Hydrology Laboratory, University of Sidi Bel Abbes, Faculty of Technology, Civil Engineering Department, 22000 Sidi Bel Abbes, Algeria
Li Li: State Key Laboratory of Intelligent Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
A.M. Zenkour: 1)Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia 2)Department of Mathematics, Faculty of Science, Kafrelsheikh University, Kafrelsheikh, Egypt
Abstract
The application of relatively low volumes of fibres in normal strength concrete has been shown to be of significant
benefit when applied to composite slabs with profiled sheet decking. This paper reports on an experimental study aimed at
quantifying further potential benefits that may arise from applying ultra-high performance fibre reinforced concrete. To assess
performance six simply supported beams were tested under hogging and sagging loading configurations along with three two
span continuous beams. Fibre contents are varied from 0% to 2% and changes in strength, deformation, crack width and
moment redistribution are measured. At the serviceability limit state, it is shown that the addition of high fibre volumes can
significantly enhance member stiffness and reduce crack widths in all beams. At the ultimate limit state it is observed that a
transition from 0% to 1% fibres significantly increases strength but that there is a maximum fibre volume beyond which no
further increases in strength are possible. Conversely, member ductility and moment redistribution are shown to be strongly
proportional to fibre volume.
Key Words
composite profile slab; crack width; flexural strength; moment redistribution; UHPFRC
Address
Sirui Chena, Phillip Visintin and Deric J. Oehlers:School of Architecture and Civil Engineering, University of Adelaide, Adelaide, SA 5005, Australia
Abstract
This article presents the numerical modelling of transient heat transfer in highly heterogeneous composite materials
where the thermal conductivity, specific heat and density are assumed to be directional-dependent. This article uses a coupled
finite element-finite difference scheme to perform the transient heat transfer analysis of unidirectional (1D) and multidirectional
(2D/3D) functionally graded composite panels. Here, 1D/2D/3D functionally graded structures are subjected to nonuniform heat
source and inhomogeneous boundary conditions. Here, the multidirectional functionally graded materials are modelled by
varying material properties in individual or in-combination ofspatial directions. Here, fully spatial-dependent material properties
are evaluated using Voigt's micromechanics scheme via multivariable power-law functions. The weak form is obtained through
the Galerkin method and solved further via the element-space and time-step discretisation through the 2D-isoparametric finite
element and the implicit backward finite difference schemes, respectively. The present model is verified by comparing it with the
previously reported results and the commercially available finite element tool. The numerous illustrations confirm the
significance of boundary conditions and material heterogeneity on the transient temperature responses of 1D/2D/3D functionally
graded panels.
Key Words
coupled FEM-FDM; Galerkin Method; inhomogeneity; micromechanics; multidirectional FGMs; transient
heat transfer
Address
Samarjeet Kumar and Vishesh Ranjan Kar:Department of Mechanical Engineering, National Institute of Technology Jamshedpur,Jharkhand, India-831014
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