Abstract
To establish digital twin model of the vehicle-bridge interaction system under random track irregularity excitation, it is necessary to compute the system response in real time. Traditional methods are time-intensive and lack real-time capability, whereas surrogate model-based approaches can rapidly and accurately predict dynamic response. This study proposes a surrogate model that employs the Sparrow Search Algorithm to optimize Long Short-Term Memory neural networks for predicting the dynamic response of vehicle-bridge interaction system under random excitation. Initially, a physical model of the vehicle-bridge interaction system is established, incorporating track irregularities to calculate the dynamic response and generate training samples. Subsequently, an SSA-LSTM surrogate model is developed and trained. Finally, the surrogate model is utilized to predict the dynamic response of the vehicle-bridge interaction system under arbitrary track irregularity excitations. To validate the robustness of the proposed algorithm, the prediction results of various surrogate models are compared. The results indicate that the proposed surrogate model achieves higher computational efficiency compared to classical mechanical models of the vehicle-bridge interaction system. Moreover, the SSA-LSTM surrogate model outperforms traditional LSTM and Backpropagation surrogate models in terms of prediction accuracy for the dynamic response of the vehicle-bridge interaction system.
Key Words
dynamic response prediction; random excitation; sparrow search algorithm; surrogate model; vehicle-bridge interaction system
Address
Tian Zhang, Yuanzhu Liu: Transportation Engineering College, Dalian Maritime University, Dalian 116026, China
Pengfei Li: Research Institute of Highway Ministry of Transport, Beijing 100088, China
Yunfeng Zou: National Engineering Research Center of High-speed Railway Construction Technology, Changsha 410075, China; School of Civil Engineering, Central South University, Changsha 410075, China
Abstract
In the present manuscript, we focus our investigation on the intralaminar hybrid composite plates, where the bending behavior is addressed employing a reliable and efficient refined high-order theory. The present refined theory successfully simulates the plate's real behavior by considering the shear effect in deformations, counting only four variables in the mathematical formulation and ensuring the parabolic distribution of these shear strains and stresses. Also, the nullity of shear stresses at the plate's top and bottom faces is guaranteed by the present refined theory. Unlike conventional composites, hybrid composite materials offer compelling features like the opportunity to create new and advantageous structures by varying the fiber combinations and proportions. This variation leads to diverse kinds of hybrid composites, each of which is intended for specific applications, depending on the characteristics expected by manufacturers. The present theory's numerical and graphical results are validated against other literature-issued high-order theories. This validation is followed by a parametric study to highlight the effect of various parameters on the behavior of hybrid composites. Based on this research, we can conclude that the suggested refined theory is reliable, precise and efficient for investigating the bending behavior of intralaminar hybrid composite plates.
Address
Belkacem Adim: Department of Civil, Mechanical and Transportation Engineering, Tissemsilt University, Tissemsilt, Algeria; Geomatics and Sustainable Development Laboratory, Ibn Khaldoun University, Tiaret, Algeria
Tahar Hassaine Daouadji: Geomatics and Sustainable Development Laboratory, Ibn Khaldoun University, Tiaret, Algeria; Department of Civil Engineering, Ibn Khaldoun University, Tiaret, Algeria
Ayed Eid Alluqmani: Department of Civil Engineering, Faculty of Engineering, Islamic University of Madinah, Al-Madinah Al-Munawara, Prince Naif Ibn Abdulaziz, Al Jamiah, Medina 42351, Saudi Arabia
Abstract
A problem of deformation of a double porous thermoelastic half space medium with fractional order heat transfer having Three-Phase-Lag (TPL) has been considered and discussed, due to the application of a thermomechanical force. A transformed procedure is taken to obtain the transformed form of result of the formulated problem. Inverse transformation of the solution is performed through a computer program for a specific model. The numerical solutions are drawn graphically for different cases. The effect of Three-Phase-Lag on Dual-Phase-Lag and the effect of fractional order and depth parameters on deformation is observed.
Address
Aseem Miglani: Department of Mathematics, Chaudhary Devi Lal University, Sirsa-125055, Haryana, India
Rajneesh Kumar: Department of Mathematics, Kurukshetra University, Kurukshetra-136119, Haryana, India
Amarjyot Kaur: Department of Mathematics, Chaudhary Devi Lal University, Sirsa-125055, Haryana, India
Monika Kalra: Department of Mathematics, Chandigarh University, Mohali-140113, Punjab, India
Abstract
Despite significant interest in the mechanics of nanostructures, the propagation behavior of guided waves in porous functionally graded (FG) doubly-curved nanoshells remains unexplored, particularly concerning the influence of different boundary constraints. The present study is therefore dedicated to addressing this void by developing a comprehensive analytical model for this problem. Based on the nonlocal strain gradient theory (NSGT) framework and incorporating the effect of moment of inertia, the governing equations of motion for porous functionally graded doubly curved shells are derived. The Galerkin technique is employed to eliminate the spatial variables from the partial differential equation system, thereby converting it into an ordinary differential equation with respect to time. By applying the boundary conditions and solving the characteristic equation, the dispersion characteristics of porous functionally graded strain gradient doubly curved shells with different boundary conditions are determined. The results indicate that the phase velocity of the hyperbolic curved plate is the smallest, followed by the cylindrical curved plate, then the ellipsoidal curved plate, with the spherical shell exhibiting the maximum phase velocity. Clearly, the spherical shell has the highest stiffness, naturally resulting in the maximum phase velocity. Additionally, at low wave numbers, the effects of nonlocal and strain gradient parameters on the dispersion relation are negligible.
Key Words
functionally graded porous material; guided wave; nanoshells; nonlocal strain gradient theory
Address
Kuineng Chen: Hunan Vocational Institute of Technology, Xiangtan 411104, China
Zipan Yang: Xiangtan Hengxin Industrial Co., Ltd., Xiangtan, 411300, China
Wubin Shan: College of Mechanical and Vehicle Engineering, Hunan University, Changsha, 410082, China
Ahmed Amine Daikh, Aicha Remil, Aicha Bessaim, Meriem Sahla, Mohammed Sid Ahmed Houari, Mohamed Oujedi Belarbi, Ahmed Drai, Mohamed Guerroudj and Mohamed A. Eltaher
Abstract
A novel refined shear deformation theory with three variables is proposed to investigate the buckling
behavior of two-directional coated functionally graded nanobeams. The displacement field is formulated based on
the principles of Euler-Bernoulli beam theory. This study examines two distinct categories of coated functionally
graded nanobeams: Hardcore and Softcore nanobeams. Three material distribution patterns are considered: a bidirectional configuration, a unidirectional transverse distribution, and a unidirectional axial arrangement. The strain gradient nonlocal elasticity theory is implemented to account for small-scale effects. The equilibrium equations
governing nanobeams are derived using the total potential energy principle. A refined solution approach, leveraging
Galerkin's method, addresses various boundary conditions efficiently. The functionally graded beam is modelled on
an elastic foundation described by the Winkler, Pasternak, and Kerr models. The obtained results show that the buckling behavior of the coated nanobeams is significantly influenced by the coating layer's thickness, material properties, boundary conditions, and gradient distribution. We find that the two-directional coating configuration can improve buckling resistance and reduce sensitivity to loading direction compared to traditional one-directional coatings. The findings of this study have important implications for the design and optimisation of nanoscale structures and devices, particularly in applications where mechanical stability and reliability are critical, such as in nanoelectromechanical systems (NEMS) and nanoscale sensors.
Key Words
buckling; complex elastic foundation; small scale effect; two-directional FGM
Address
Ahmed Amine Daikh: Artificial Intelligence Laboratory for Mechanical and Civil Structures, and Soil, University of Naama, P.O. Box 66, 45000 Naama, Algeria; Laboratoire d'Etude des Structures et de Mécanique des Matériaux, Département de Génie Civil, Faculté des Sciences et de la Technologie, Université Mustapha Stambouli, B.P. 305, 29000 Mascara, Algeria
Aicha Remil: Laboratoire d'Etude des Structures et de Mécanique des Matériaux, Département de Génie Civil, Faculté des Sciences et de la Technologie, Université Mustapha Stambouli, B.P. 305, 29000 Mascara, Algeria
Aicha Bessaim: Laboratoire d'Etude des Structures et de Mécanique des Matériaux, Département de Génie Civil, Faculté des Sciences et de la Technologie, Université Mustapha Stambouli, B.P. 305, 29000 Mascara, Algeria; Faculty of Architecture and Civil Engineering, USTO, BP 155, Oran El Mnaoer, Oran, Algeria
Meriem Sahla: Laboratoire d'Etude des Structures et de Mécanique des Matériaux, Département de Génie Civil,
Faculté des Sciences et de la Technologie, Université Mustapha Stambouli, B.P. 305, 29000 Mascara, Algeria
Mohammed Sid Ahmed Houari: Laboratoire d'Etude des Structures et de Mécanique des Matériaux, Département de Génie Civil, Faculté des Sciences et de la Technologie, Université Mustapha Stambouli, B.P. 305, 29000 Mascara, Algeria
Mohamed Oujedi Belarbi: Laboratoire de Recherche en Génie Civil, LRGC, Université de Biskra, B.P. 145, 07000 Biskra, Algeria
Ahmed Drai: Laboratory of Applied Biomechanics and Biomaterials, EN Oran, BP1513 El Mnaour, 31000 Oran, Algeria; Department of Mechanical Engineering, University of Mustapha Stambouli, Mascara, Algeria
Mohamed Guerroudj: Laboratory of Applied Biomechanics and Biomaterials, EN Oran, BP1513 El Mnaour, 31000 Oran, Algeria
Mohamed A. Eltaher: Mechanical Design and Production Department, Faculty of Engineering, Zagazig University,
P.O. Box 44519, Zagazig, Egypt; Mechanical Engineering Department, Faculty of Engineering, King Abdulaziz University, P.O. Box 80204, Jeddah, Saudi Arabi
