Abstract
The extensive application of steel material in Chinese archaized buildings not only represents the unique exterior
appearance of traditional architecture but also effectively addresses issues such as the susceptibility to decay and deformation in
wooden structures. However, conventional rigid beam-column welded connections in steel archaized buildings are prone to
premature rupture under seismic events. To further enhance the energy dissipation capacity and post-earthquake repairability of
beam-column joints in steel archaized buildings, this paper proposes a self-centering energy dissipation device composed of
shape memory alloy (SMA) bars and friction dampers connected in series. Four full-scale joint specimens with different joint
stiffnesses were designed and subjected to low-cycle repeated loading tests. The results indicated that the combination of semi
rigid beam-column joints and self-centering energy dissipation devices using shear-type friction dampers exhibit stronger energy
dissipation and load-bearing capacities with minimal residual deformation compared to other configurations. Based on
experimental results, a three-dimensional numerical model was established using ABAQUS finite element software to
investigate the effects of beam end-plate thickness and the length of weak zone in the extended limb length in angle steels on the
mechanical performance, energy dissipation capacity, residual deformation, and self-centering performance of beam-column
joints in steel archaized buildings equipped with SMA bar-friction damper series devices. Finally, design recommendations were
provided for the end-plate of the beam and the replaceable angle steel at the beam-column joints in steel archaized buildings.
Key Words
replaceability; semi-rigid beam-column joint; SMA bar-friction damper series device; steel archaized
building
Address
Liangjie Qi:1)School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China 2)Key Lab of Structural Engineering and Earthquake Resistance, Ministry of Education (XAUAT), Xi'an 710055, China
Mengfei Ding:School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
Zhen Yuan:China Railway Chang'an Heavy Industry Co., Ltd., Xi'an 710032, China
Gaoming Xue:School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
Jose R. Albiol-Ibanez:DCAR (Architectonic Constructions Department), UPV Universitat Politecnica de Valencia, C/Vera S/N, Valencia 46022, Spain
Abstract
In the current manuscript, bending, buckling and vibration analysis of functionally graded carbon nanotube
reinforced composite beams on the Winkler–Pasternak foundation are presented and discus. The advantages of the present
theory over other higher-order theories are the inclusion of a displacement field containing undetermined integral terms. This
theory incorporates both shear deformation. In addition, the present theory does not require shear correction factors as in the case
of Timoshenko beam theory. A higher-order displacement field variables is proposed to calculate the stability response of
functionally graded carbon nanotube-reinforced composite (FG-CNT) beams Hamilton principle and Navier's method to obtain
the stability of FG-CNT beams by explaining an eigenvalue problem. Four different carbon nanotubes (CNTs) distributions
including uniform and three types of functionally graded distributions of CNTs through the thickness are considered. The rule of
mixture is used to describe the effective material properties of the nanocomposite beams. The accuracy of this theory is
demonstrated according to some numerical examples and comparisons with the corresponding data in the literature.
Key Words
beam; FG-CNT; new integral shear deformation theory; Pasternak foundation; reinforced composite
Address
Mokhtar Ellali:Smart Structures Laboratory, University of Ain Témouchent ,46000, Algeria
Mokhtar Bouazza:1)Department of Civil Engineering, University Tahri Mohammed of Bechar,Bechar 08000, Algeria
2)Laboratory of Materials and Hydrology (LMH), University of Sidi Bel Abbes, Sidi Bel Abbes 2200, Algeria
Mohamed A. Eltaher:1)Mechanical Design and Production Dept., Faculty of Engineering, Zagazig University, P.O. Box 44519, Zagazig, Egypt
2)Mechanical Engineering Department, Faculty of Engineering, King Abdulaziz University, P.O. Box 80204, Jeddah, Saudi Arabia
Noureddine Benseddiq:Lille Mechanics Unit–UML, ULR 7512, University of Lille, Villeneuve d'Ascq, France
Abstract
In the present research, an attempt was made to improve the behavior of T-stub connections by providing stiffener
details for these joints and then investigating the effect of using the proposed stiffener on the joint with non-rolled tee profiles. In
this regard, five full-scale experimental samples were constructed and tested. The first sample was considered a control sample,
which was designed and manufactured based on the regulations. The next two samples were constructed with rolled tee sections
using proposed stiffeners of different thicknesses. In the next two specimens, the T-stub connection was constructed using the
non-rolled tee sections, and in one of the specimens, the proposed stiffener was used. The tests were performed under quasi
static cyclic loading, and based on their results, the seismic parameters of ultimate strength, effective stiffness, ductility, and
energy dissipation capacity were evaluated. The results of connections with rolled tee sections indicated that the proposed
stiffeners increased ultimate rotational strength by up to 13.8%, effective stiffness by 92%, energy dissipation capacity by 67%,
and ductility by 58%. Adding stiffeners to non-rolled tee sections boosted rotational strength by 12%, stiffness by 117%,
ductility by 59%, and energy dissipation by 62%, significantly improving T-stub connection behavior.
Key Words
bolted -T-stub steel connections; ductility; energy dissipation capacity; experimental test; stiffener
Address
Mehrdad Rasoulitabar:Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
Mehrzad TahamoliRoudsari:Department of Civil Engineering, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran
Parham Memarzadeh:Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
Farshid Fathi:Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
Abstract
To promote sustainable steel-concrete composite structures, it is essential to develop special shear connectors that
facilitate accelerated construction and deconstruction. A lockbolt demountable shear connector (LBDSC) was recently proposed.
While the LBDSC has been evaluated using horizontal and vertical (standard) push-out tests, it is essential to further assess the
disassembly mechanism and the positive flexural performance of prefabricated demountable composite beams (PDCBs) under
both serviceability and ultimate limit states. Two full-scale test specimens of PDCBs with LBDSC were designed with partial
shear connections and assessed using a three or four-point load beam setup under both cyclic and static monotonic loading
conditions. The experimental results indicate that the failure modes of the PDCBs include longitudinal cracking in the grout
between concrete slabs along the composite beam. Additionally, the demountable composite beams exhibited typical ductile
flexural failure. The disassembly and reassembly of the PDCB were evaluated using a cyclic loading setup, and the results
indicated that the structural performance of the PDCB was not compromised. The experimental results for load-carrying
capacity and elastic stiffness of the PDCB were compared to the corresponding values from composite beam theory and the
provisions in Eurocode 4. The agreement between the tested and calculated results validates the applicability of the Eurocode 4
equations to demountable composite beams utilizing LBDSCs.
Address
Jun He:1)School of Civil Engineering, Changsha University of Science and Technology, Hunan, China
2)Key Laboratory for Green Construction and Maintenance of Bridges and Buildings of Hunan Province, China
Zitong Wang:School of Civil Engineering, Changsha University of Science and Technology, Hunan, China
Sidong Feng:School of Civil Engineering, Changsha University of Science and Technology, Hunan, China
George Vasdravellis:Key Laboratory for Green Construction and Maintenance of Bridges and Buildings of Hunan Province, China
Mauricio Paul Chiliquinga Chicaiza:Institute for Infrastructure and Environment, Heriot-Watt University, Edinburgh, UK
Ahmed S.H. Suwaed:Department of Reconstruction and Projects, University of Baghdad, Iraq
Abstract
This study aimed to develop a model to accurately predict the acceleration of structural systems during an
earthquake. The acceleration and applied force of a structure were measured at current time step and the velocity and
displacement were estimated through linear This paper studies the vibrating behavior of axially moving sandwich plates with
carbon nanotubes-reinforced composite face sheets and honeycomb core. To evaluate and select an appropriate structure, various
cores including polyurethane foam, balsa wood, and honeycomb are examined. Governing partial differential equations are
derived using sinusoidal shear deformation theory and within the framework of Hamilton's principle. Halpin–Tsai model is
applied to predict the elasticity of composite material based on the geometry and uniformly distributed and random orientation
of carbon nanotubes through the epoxy resin matrix. A semi-analytical method is developed for calculating the moving speed
and natural frequencies of the sandwich structure. The accuracy of presented results is verified by comparing predicted results
with research that is available in the previous literature. The detailed parametric study is focused on the effects of various cores,
lateral ratio, the thickness of the core-to-face sheet ratio, the thickness-to-length ratio of the honeycomb cell, angles of the
honeycomb cell, dimensionless speed, boundary conditions, and different modes. Results indicated that axial velocity and
geometrical ratios improve the vibrational behavior of sandwich nanocomposite plates. The results of this investigation can be
presented as a useful reference in the design and manufacturing of marine vessels and aircraft.
Key Words
axially moving; honeycomb core; nanocomposite; sandwich plate; vibration
Address
Elham Haghparast:Faculty of Mechanical Engineering, University of Kashan, Kashan, Iran
Ali Ghorbanpour Arani:1)Faculty of Mechanical Engineering, University of Kashan, Kashan, Iran
2)Institute of Nanoscience & Nanotechnology, University of Kashan, Kashan, Iran
Amir Hossein Soltan Arani:Faculty of Mechanical Engineering, University of Kashan, Kashan, Iran
Abstract
Cables are an essential component of bridge structures, and their safety is directly related to the service life of the
bridge. In particular, the change in cable force is a crucial indicator for assessing the safety of the cable. In this paper, the
acceleration signal of the cable structure is obtained using a structural health monitoring (SHM) system, and the signal is
transformed into the time-domain frequency using the Fourier transform method (FFT). Then, the frequency-cable force
equation is established to quickly and accurately obtain the change in cable force in the time domain. Finally, the statistics of the
cable force range are obtained using the rainflow counting method. This method enables the rapid and accurate assessment of
the fatigue life of the cable structure when physical parameters of the cable are available. In particular, a probability prediction
model is constructed based on the Bayesian emulator, and the influence of three covariance functions (Squared Exponential
(SE), Matern-3/2 (MA-3/2), and Matern-5/2 (MA-5/2)) on the prediction performance is discussed, which is verified using the
SHM data. The results indicate that for acceleration signal data with significant environmental noise, the Bayesian model based
on MA-3/2 covariance performs the best in terms of prediction. However, when the acceleration signal data is relatively smooth,
the prediction performance of the Bayesian model based on the three covariance functions is the same. At the same time, by
combining on-site monitoring data, it can be inferred that the fatigue life of the bridge stay cables is greater than the service life,
meeting the safety requirements for bridge operation and maintenance.
Key Words
cable force assessment; covariance functions; fatigue life; fourier transform method; probability prediction
model; rain flow counting; structural health monitoring
Address
Kai Cao:1)State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China
2)Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China
Yang Ding:Department of Civil Engineering, Hangzhou City University, Hangzhou 310015, China
Hui Li:Department of Transportation, Southeast University, Nanjing, 210096, China
Tong-Lin Yang:Centre for Molecular Systems and Organic Devices, Key Laboratory for organic Electronics and Information Displays & Jiangsu Key
Laboratory for Biosensors, Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, Nanjing 210023, China
Gang-Gui Liu:Department of Civil Engineering, Hangzhou City University, Hangzhou 310015, China
Tian-Yun Chu:Jiaxing Tiankun Construction Engineering Design Co., Ltd., Jiaxing 314000, China
