Abstract
The impact problem of imperfect beams is crucial in engineering fields such as water conservancy and
transportation. In this paper, the low velocity impact of graphene reinforced metal foam beams with geometric defects is studied
for the first time. Firstly, an improved Hertz contact theory is adopted to construct an accurate model of the contact force during
the impact process, while establishing the initial conditions of the system. Subsequently, the classical theory was used to model
the defective beam, and the motion equation was derived using Hamilton's principle. Then, the Galerkin method is applied to
discretize the equation, and the Runge Kutta method is used for numerical analysis to obtain the dynamic response curve.
Finally, convergence validation and comparison with existing literature are conducted. In addition, a detailed analysis was
conducted on the sensitivity of various parameters, including graphene sheet (GPL) distribution pattern and mass fraction,
porosity distribution type and coefficient, geometric dimensions of the beam, damping, prestress, and initial geometric defects of
the beam. The results revealed a strong inhibitory effect of initial geometric defects on the impact response of beams.
Key Words
GPLRMF beams; Hertz contact theory; initial geometric imperfection; low-velocity impact; The Galerkin
method
Address
Yi-Han Cheng and Gui-Lin She:College of Mechanical and Vehicle Engineering, Chongqing University, Chongqing 400044, China
Abstract
The work researched the application of artificial intelligence to the design and analysis of advanced nanoplates, with
a particular emphasis on size and surface effects. Employing an integrated theoretical framework, this study developed a more
accurate model of complex nanoplate behavior. The following analysis considers nanoplates embedded in a Pasternak
viscoelastic fractional foundation and represents the important step in understanding how nanoscale structures may respond
under dynamic loads. Surface effects, significant for nanoscale, are included through the Gurtin-Murdoch theory in order to
better describe the influence of surface stresses on the overall behavior of nanoplates. In the present analysis, the modified
couple stress theory is utilized to capture the size-dependent behavior of nanoplates, while the Kelvin-Voigt model has been
incorporated to realistically simulate the structural damping and energy dissipation. This paper will take a holistic approach in
using sinusoidal shear deformation theory for the accurate replication of complex interactions within the nano-structure system.
Addressing different aspectsof the dynamic behavior by considering the length scale parameter of the material, this work aims at
establishing which one of the factors imposes the most influence on the nanostructure response. Besides, the surface stresses that
become increasingly critical in nanoscale dimensions are considered in depth. AI algorithms subsequently improve the
prediction of the mechanical response by incorporating other phenomena, including surface energy, material inhomogeneity, and
size-dependent properties. In these AI- enhanced solutions, the improvement of precision becomes considerable compared to the
classical solution methods and hence offers new insights into the mechanical performance of nanoplates when applied in
nanotechnology and materials science.
Abstract
Punching shear is a brittle failure that occurs within the RC flat slabs where stresses are concentrated within small
regions, resulting in a catastrophic and unfavorable progressive collapse. However, increasing the slab slenderness ratio is
believed to significantly affect the slab's behavior by the induced strain values throughout the slab depth. This study examines
the punching shear behavior of flat slabs by the nonlinear finite element analysis approach using ABAQUS software, where 72
models were investigated. The parametric study includes the effect of opening existence, opening-to-column ratio (O/C),
temperature level, slenderness ratio (L/d), and flexural reinforcement rebar diameter. The behavior of the punching shear failure
was fully examined under elevated temperatures which was not previously considered in detail along with the combined effect
of the other sensitive parameters (opening size, slab slenderness, and reinforcement rebar size). It has been realized that
increasing the slab slenderness has a major role in affecting the slab's structural behavior, besides the effect of the flexural
reinforcement ratio. Reducing the slab's slenderness from 18.27 to 5.37 increased the cracking load by seven times for the slab
without openings compared to nine times for the initial stiffness value. In addition, the toughness capacity is reduced up to 80%
upon creating an opening, where the percentage is further increased by increasing the opening size by about an additional 10%.
Finally, the ultimate deflection capacity of flat slabs with an opening is increased compared to the solid slab with the
enhancement being increased for openings of larger size, larger depths, and higher exposure temperature.
Address
Rajai Z. Al-Rousan:Department of Civil Engineering, Faculty of Engineering, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan
Bara'a R. Alnemrawi:Department of Civil Engineering, Faculty of Engineering, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan
Abstract
This paper discusses the study of concrete composite walls of algorithmic modeling, in which steel tubes are
embedded. The load-bearing capacity of STHC composite walls increases with the increase of axial load coefficient, but its
ductility decreases. The load-bearing capacity can be improved by increasing the strength of the steel pipes; however, the
elasticity of STHC composite walls was found to be slightly reduced. As the shear stress coefficient increases, the load-bearing
capacity of STHC composite walls decreases significantly, while the deformation resistance increases. By analyzing actual
cases, we demonstrate the effectiveness of the research results in real situations and enhance the persuasiveness of the
conclusions. The research results can provide a basis for future research, inspire more explorations on seismic design and
construction, and further advance the development of this field. Emphasize the importance of research results, promote
interdisciplinary cooperation in the fields of structural engineering, earthquake engineering, and materials science, and improve
overall seismic resistance. The emphasis on these aspects will help highlight the practical impact of the research results, further
strengthen the conclusions, and promote progress in the design and construction of earthquake-resistant structures. The goals of
this work are access to adequate, safe and affordable housing and basic services, promotion of inclusive and sustainable
urbanization and participation, implementation of sustainable and disaster-resilient architecture, sustainable planning and
management of human settlements. Simulation results of linear and nonlinear structures show that this method can detect
structural parameters and their changes due to damage and unknown disturbances. Therefore, it is believed that with the further
development of fuzzy neural network artificial intelligence theory, this goal will be achieved in the near future.
Key Words
AI computer aided intelligent; composite walls; FEM analysis; fuzzy model; high-strength concrete;
mechanical behavior; resilient and sustainable
Address
ZY Chen:School of Science, Guangdong University of Petrochemical Technology, Maoming, Guangdong, China
Ruei-Yuan Wang:School of Science, Guangdong University of Petrochemical Technology, Maoming, Guangdong, China
Yahui Meng:School of Science, Guangdong University of Petrochemical Technology, Maoming, Guangdong, China
Huakun Wu:School of Computer Science, Guangdong Polytechnic Normal University, Guangzhou, Guangdong, China
Lai:School of Science, Guangdong University of Petrochemical Technology, Maoming, Guangdong, China
Timothy Chen:Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA 91125, USA
Abstract
In the present analysis, the buckling behavior of smart beams integrated into racket frames for enhancing player
control was examined by numerical solutions and sinusoidal shear deformation theory. The smart beam under consideration is
subjected to an external voltage in the thickness direction. The integration of this smart material into the structure of the racket
should optimize performance, improving the racket's stability and responsiveness during play. In this, an accurate representation
of complex shear effects is made by using a sinusoidal shear deformation theory, while the solution of the resulting governing
equations is made by numerical methods. The critical buckling loads and the characteristics of deformation obtained through the
analysis provide insight into some design parameters controlling and influencing stability. Obtained results are validated with
other published works. The length and thickness of the beam, elastic medium, boundary condition, and influence of external
voltages have been represented for buckling load in the structure. These results will help in designing smart racket frames using
smart beams to provide more precision and control for the players in an intelligent way.
Abstract
This paper researched on the bending vibration characteristics of composite drive shaft with internal damping. To
analyze the unbalanced excitation response in full speed range, a transfer matrix model was built based on the improved Layerwise theory and the numerical damping, and compared with the metal drive shaft. The results show that the effect of internal
damping of the composite shaft tube on bending vibration response was different in the subcritical, critical and supercritical
speed ranges. Then, the finite element analysis and vibration tests were carried out to verify the analysis results of transfer matrix
model.
Key Words
bending vibration; composite; drive shaft; full speed range; internal damping
Address
Mo Yang:Hubei Longzhong Laboratory, Hubei University of Arts and Science, Xiangyang, 441000, China
Haonan Hu:School of Mechanical Engineering, Hubei University of Arts and Science, Xiangyang, 441053, China
Xian Zhou:School of Mechanical Engineering, Hubei University of Arts and Science, Xiangyang, 441053, China
Wen Zhang:School of Mechanical Engineering, Hubei University of Arts and Science, Xiangyang, 441053, China
Yuebin Zhou:School of Mechanical Engineering, Hubei University of Arts and Science, Xiangyang, 441053, China
Yikun Wang:School of Mechanical Engineering, Hubei University of Arts and Science, Xiangyang, 441053, China
Jianmin Ye:School of Mechanical Engineering, Hubei University of Arts and Science, Xiangyang, 441053, China
Abstract
An advanced numerical method is proposed in this paper for the second-order inelastic dynamic analysis of cablestayed bridges using rectangular concrete-filled steel tubular (CFST) columns under earthquake loadings for the first time. The
proposed method can exactly predict the nonlinear response of the bridges by using only one element per member in simulating
the structural model. This comes from considering both the geometric and material nonlinearities in a fiber beam-column
element and a catenary cable element. In the fiber beam-column element, the geometric nonlinearities are captured by applying
the stability functions, whereas the material nonlinearities are evaluated by tracing the uniaxial cyclic stress-strain curves of each
fiber on the cross-sections, which are located at the integration points along the member length. A computer program was
developed based on Newmark's average acceleration algorithm to solve the nonlinear equations of motion. The accuracy and
computational efficiency of the proposed program were verified by comparing the predicted results with the experimental
results, and the results obtained from the commercial software SAP2000 and ABAQUS. The proposed program is promising as
a useful tool for practical designs for the nonlinear inelastic dynamic analysis of cable-stayed bridges.
Address
Van-Tuong Bui and Seung-Eock Kim:Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-dong, Gwangjin-gu, Seoul, 05006, South Korea
Abstract
Suspension bridges are critical to urban transportation, but those in earthquake-prone areas face unique challenges.
In the event of a moderate or strong earthquake, conventional linear theory-based approaches for detecting bridge damage
become inadequate. This study presents an efficient method for identifying damage in suspension bridges using time history
nonlinear inelastic analysis. A practical advanced analysis program is employed to model cable-supported bridges with low
computational cost, generating a dataset for four hybrid models: PSO-DT, PSO-RF, PSO-XGB, and PSO-CGB. These models
combine decision tree (DT), random forest (RF), extreme gradient boosting (XGB), and categorical gradient boosting (CGB)
with particle swarm optimization (PSO) to capture nonlinear correlations between displacement response and damage. Principal
component analysis reduces dataset dimensions, and PSO selects the optimal model. A numerical case study of a suspension
bridge under simulated earthquake conditions identifies PSO-XGB as the best model for predicting stiffness reduction. The
results demonstrate the method's robustness for nonlinear damage detection in suspension bridges under earthquake excitation.
Address
Van-Thanh Pham:1)Department of Civil and Environmental Engineering, Sejong University, Seoul 05006, South Korea
2)Faculty of Civil Engineering, Thuyloi University, 175 Tay Son, Dong Da, Hanoi, Vietnam
Duc-Kien Thai:Department of Civil and Environmental Engineering, Sejong University, Seoul 05006, South Korea
Seung-Eock Kim:Department of Civil and Environmental Engineering, Sejong University, Seoul 05006, South Korea
