Computers & Structures最新文献_第9页

Nonprobabilistic reliability analysis method for series-parallel structural systems with correlated uncertainties 具有相关不确定性的串并联结构系统的非概率可靠性分析方法

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2024-07-01 DOI: 10.1016/j.compstruc.2024.107459

Jinglei Gong, Xiaojun Wang, Yongxiang Mu

引用次数: 0

Anti-creep pretension determination of a mesh reflector antenna for long term surface accuracy retention 为长期保持表面精度而测定网状反射天线的防坍塌预拉力

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2024-06-29 DOI: 10.1016/j.compstruc.2024.107460

Jun Zhang , Baiyan He , Rui Nie , Guobiao Wang , Yesen Fan

{"title":"Anti-creep pretension determination of a mesh reflector antenna for long term surface accuracy retention","authors":"Jun Zhang , Baiyan He , Rui Nie , Guobiao Wang , Yesen Fan","doi":"10.1016/j.compstruc.2024.107460","DOIUrl":"https://doi.org/10.1016/j.compstruc.2024.107460","url":null,"abstract":"<div><p>During the in-orbit service, mesh reflector antennas inevitably withstand the long-term creep behavior, resulting in changes in material properties and loss of cable tensions, thus decreasing the structural stiffness and surface accuracy. Pretension design plays an important role for mesh reflector antennas in achieving high surface accuracy, and different levels of pretension also affect the antenna’s creep behavior in the time dimension, which can be actively utilized to improve stability of the antenna surface accuracy. In this paper, we present an anti-creep pretension determination method for mesh reflector antennas to improve the surface accuracy stability. The creep model in the discretized time domain is adopted to describe the cable creep behavior. The time-related nonlinear equilibrium equation of the mesh reflector antenna is established with the force density method. The time-related tangent stiffness matrix is derived and adopted to solve the nonlinear equilibrium equation by the Newton-Raphson method, providing an effective way to analyze the antenna creep phenomenon in the discretized time domain. Aiming to minimize the long-term peak value of the time-variant surface error, the pretension schemes are generated and optimized. Finally, this approach is effectively applied to a thirty-unit mesh reflector antenna and its feasibility and effectiveness are verified.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141483412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hybrid vehicle scanning techniques for detection of damaged hangers in tied-arch railway bridges 用于检测系杆拱铁路桥受损吊架的混合车辆扫描技术

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2024-06-26 DOI: 10.1016/j.compstruc.2024.107441

J.D. Yau , S. Urushadze

{"title":"Hybrid vehicle scanning techniques for detection of damaged hangers in tied-arch railway bridges","authors":"J.D. Yau , S. Urushadze","doi":"10.1016/j.compstruc.2024.107441","DOIUrl":"https://doi.org/10.1016/j.compstruc.2024.107441","url":null,"abstract":"<div><p>Regular monitoring of the hanger system is essential for preserving structural integrity in tied-arch bridges. This proactive monitoring enables preventive maintenance and early detection of hanger damage. To confront this issue, we propose a novel scanning method for assessing the impact of damaged hangers on the dynamic behaviour of single-span tied-arch railway bridges. Using each hanger as a positional reference, this method employs an instrumented vehicle as a mobile scanner to indirectly acquire vibration data from the traversed bridge deck. The hybrid approach integrates vehicle-bridge interaction (VBI) dynamics, vehicle scanning method (VSM), and moving windowed Fourier transform (mw-FT) technique to generate time–frequency spectrograms from the collected signals. In this representation, the time axis indicates the duration of the inspection vehicle traversing the bridge deck. By analysing frequency shifts within the spectrogram, we can identify damaged hangers through observed variations in frequency content over time. Numerical studies demonstrate the efficacy of the proposed hybrid vehicle scanning technique in detecting potential hanger damage in tied-arch railway bridges.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141483029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Efficient neural network-aided seismic life-cycle cost optimization of steel moment frames 钢弯矩框架抗震寿命周期成本的高效神经网络辅助优化

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2024-06-25 DOI: 10.1016/j.compstruc.2024.107443

Saeed Gholizadeh , Oğuzhan Hasançebi

{"title":"Efficient neural network-aided seismic life-cycle cost optimization of steel moment frames","authors":"Saeed Gholizadeh , Oğuzhan Hasançebi","doi":"10.1016/j.compstruc.2024.107443","DOIUrl":"https://doi.org/10.1016/j.compstruc.2024.107443","url":null,"abstract":"<div><p>In this paper, a novel and efficient neural network-based methodology is proposed to achieve seismic total cost optimization of steel moment-resisting frames in a timely manner. The computational burden of an optimization process based on performing nonlinear time-history analysis is prohibitively high. To address this crucial issue, a new and efficient neural network model is proposed in this paper to accurately predict the nonlinear time history response of steel frames during the optimization process. In the proposed neural network model, an ensemble of parallel neural networks is used to provide excellent prediction accuracy. In addition, a new repairability constraint is proposed to check the seismic damage level of structures during the optimization process with the aid of the proposed neural network model. Moreover, an efficient metaheuristic algorithm is used to achieve the optimization task. Two numerical examples are illustrated to demonstrate the efficiency of the proposed methodology. The results show that the proposed neural network model outperforms the existing standard models in terms of prediction accuracy. Furthermore, it is shown that by using the proposed methodology, the optimal seismic total cost of steel frames increases by less than 2.5%, yet their seismic collapse capacity increases by at least 30%.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141483027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Topological optimization for tailored designs of advection–diffusion-reaction porous reactors based on pore scale modeling and simulation: A PNM-NSGA framework 基于孔隙尺度建模和模拟的多孔反应器定制设计拓扑优化：PNM-NSGA 框架

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2024-06-25 DOI: 10.1016/j.compstruc.2024.107452

Mehrzad Alizadeh , Jeff Gostick , Takahiro Suzuki , Shohji Tsushima

{"title":"Topological optimization for tailored designs of advection–diffusion-reaction porous reactors based on pore scale modeling and simulation: A PNM-NSGA framework","authors":"Mehrzad Alizadeh , Jeff Gostick , Takahiro Suzuki , Shohji Tsushima","doi":"10.1016/j.compstruc.2024.107452","DOIUrl":"https://doi.org/10.1016/j.compstruc.2024.107452","url":null,"abstract":"<div><p>Reactive transport within porous reactors is crucial to many diverse applications, and the efficacy of these reactors hinges on their microstructure. Mathematical modeling and optimization play a pivotal role in the exploration of efficient designs, enabling the generation of structures that may not be achievable through random realizations of packings. In this study, we propose a framework for high-resolution topological optimization of porous flow-through reactors based on pore-scale simulations using a non-dominated sorting genetic algorithm II. A pore network model for an advection–diffusion-reaction system is developed to simulate reactor performance. This model is integrated with a mathematical optimization algorithm, incorporating a background grid and Delaunay tessellation. The optimization framework generates enhanced porous structures, simultaneously maximizing conversion rates while minimizing pumping costs. Striking a balance between permeability and reactive surface area, the final designs yield a set of Pareto optimal solutions, encompassing diverse non-dominated designs with varying reaction rates and hydraulic requirements. The results demonstrate that optimal pore configurations lead to a 280% increase in conversion rates and a 6% reduction in pumping costs at one end, while on the opposite end of the Pareto front, a 15.2% increase in reaction rates and an 11.3% reduction in pumping costs are observed.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0045794924001810/pdfft?md5=f75e183292afe805c3a65ff7e63e1ea5&pid=1-s2.0-S0045794924001810-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141483028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A thermal model for topology optimization in additive manufacturing: Design of support structures and geometry orientation 用于增材制造拓扑优化的热模型：支撑结构和几何方向的设计

IF 4.7 2区工程技术

Computers & Structures Pub Date : 2024-06-18 DOI: 10.1016/j.compstruc.2024.107453

Geovane Augusto Haveroth , Carl-Johan Thore , Roberto Federico Ausas , Stefan Jakobsson , José Alberto Cuminato , Maicon Ribeiro Correa

{"title":"A thermal model for topology optimization in additive manufacturing: Design of support structures and geometry orientation","authors":"Geovane Augusto Haveroth , Carl-Johan Thore , Roberto Federico Ausas , Stefan Jakobsson , José Alberto Cuminato , Maicon Ribeiro Correa","doi":"10.1016/j.compstruc.2024.107453","DOIUrl":"https://doi.org/10.1016/j.compstruc.2024.107453","url":null,"abstract":"<div><p>In this study, we present an efficient Topology Optimization (TO) approach designed to optimize support structures in metal Additive Manufacturing (AM), with a particular focus on Powder Bed Fusion (PBF) technology. The developed framework uses a purely thermal formulation to identify regions within the design that are susceptible to high heat concentrations. In the proposed modeling of the AM process, we postulate that new material layers are included in a partially built design that has already cooled to a controlled temperature. This aspect provides a layer-by-layer model of AM entirely local, enabling the building process parallelization and resulting in an algorithm with superior computational efficiency. Numerical results show the robustness of the proposed strategy, with the successful incorporation of support structures beneath overhanging surfaces and their effectiveness across a wide range of geometries and orientations. Furthermore, this framework is also applied to optimize the geometry orientation within the build chamber, further enhancing its applicability in the AM context.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141423363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A framework specialized for large-scale vehicle–bridge interaction simulation 大规模车辆-桥梁相互作用模拟专用框架

IF 4.7 2区工程技术

Computers & Structures Pub Date : 2024-06-14 DOI: 10.1016/j.compstruc.2024.107429

Zhuoran Han, Chul-Woo Kim, Kai-Chun Chang

{"title":"A framework specialized for large-scale vehicle–bridge interaction simulation","authors":"Zhuoran Han, Chul-Woo Kim, Kai-Chun Chang","doi":"10.1016/j.compstruc.2024.107429","DOIUrl":"https://doi.org/10.1016/j.compstruc.2024.107429","url":null,"abstract":"<div><p>The coupled motion between bridges and vehicles is known as vehicle–bridge interaction (VBI). It is crucial for bridge design, monitoring, and vehicle safety and comfort. VBI studies typically rely on general-purpose finite element (FE) software. Although precise, they are not optimized for simulating large-scale bridges with numerous vehicles, which can result in long processing times and modeling challenges. This paper presents a self-developed framework in MATLAB™ for large-scale VBI simulation. The framework divides the simulation task into five modules and supports asynchronous seismic excitation (ASE), handles different deck geometries, unifies all road vehicle models and inputs with a vehicle library, supports variable vehicle velocity (VVV) and different traffic scenarios, and handles wheel–deck detachment. All functions have been designed with easily accessible interfaces to facilitate secondary development. The framework was verified using a 2D sprung mass benchmark case compared to a closed-form solution, and a 3D simplified model compared to commercial FE software. It was also validated through a laboratory experiment. Further demonstrations of a large-scale VBI system highlighted new phenomena and emphasized the significance of considering the ASE effect in similar systems. With ongoing improvements, the framework has the potential to become a practical tool for VBI simulation.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0045794924001585/pdfft?md5=635b9f5a79c6fec2624ec0a372c1bcfe&pid=1-s2.0-S0045794924001585-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141323683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Topology optimization of the electrodes in dielectrophoresis-based devices 基于介电泳装置的电极拓扑优化

IF 4.7 2区工程技术

Computers & Structures Pub Date : 2024-06-14 DOI: 10.1016/j.compstruc.2024.107444

Abbas Homayouni-Amlashi, Laure Koebel, Alexis Lefevre, Abdenbi Mohand-Ousaid, Aude Bolopion

{"title":"Topology optimization of the electrodes in dielectrophoresis-based devices","authors":"Abbas Homayouni-Amlashi, Laure Koebel, Alexis Lefevre, Abdenbi Mohand-Ousaid, Aude Bolopion","doi":"10.1016/j.compstruc.2024.107444","DOIUrl":"https://doi.org/10.1016/j.compstruc.2024.107444","url":null,"abstract":"<div><p>This paper aims for developing topology optimization methodology to design the shape of electrodes in Dielectrophoresis (DEP)-based devices. The DEP force is due to a non-uniform electric field induced by applied voltages to the electrodes. Shape of the electrodes has the principal effect on the direction and magnitude of the DEP force. In medical therapy microfluidic devices, DEP force is used for cell sorting and cell separation. While the direction and magnitude of the DEP force are desired to be determined and maximized respectively, the magnitude of the electric field should be minimized to avoid damaging cells. Approaching these goals is counter intuitive where the existing electrode designs are basic. Therefore, a detailed finite element model (FEM) is developed for DEP force and electric field to formulate an optimization problem to maximize the DEP force in a particular direction while there is a constraint on electric field's magnitude. Using the developed FEM, explicit formulations for sensitivity analysis are derived to implement a gradient-based topology optimization. The performance of developed methodology is assessed numerically to determine the direction of the DEP force and constraining the electric field and experimentally in a practical case study of particle trapping in a microfluidic channel.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141323684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Vine copulas for accelerated prediction of composite strength variability 用于加速预测复合材料强度变异性的藤蔓共生系数

IF 4.7 2区工程技术

Computers & Structures Pub Date : 2024-06-12 DOI: 10.1016/j.compstruc.2024.107440

B. Van Bavel , D. Vandepitte , D. Moens

{"title":"Vine copulas for accelerated prediction of composite strength variability","authors":"B. Van Bavel , D. Vandepitte , D. Moens","doi":"10.1016/j.compstruc.2024.107440","DOIUrl":"https://doi.org/10.1016/j.compstruc.2024.107440","url":null,"abstract":"<div><p>Composite materials are essential for many advanced engineering applications, but numerical quantification of strength variability can be computationally expensive. This paper proposes a novel methodology that drastically reduces the number of finite element simulations required to characterise composite material strength variability using the concept of vine copulas. This concept provides a flexible tool for the representation of high-dimensional dependencies. The methodology considers spatial scatter of three material variabilities: fibre volume fraction, fibre misalignment and fibre strength. First, the cross-correlation between stress, fibre volume fraction and fibre misalignment is fitted by a vine copula using results from a limited number of finite element simulations. Next, the vine copula is used to predict new conditional stress realisations when given realisations for the fibre volume fraction and fibre misalignment. This effectively replaces the finite element simulations with a vine copula that is much faster to evaluate. The methodology is verified by predicting the tensile failure load of a unidirectional composite coupon. Predictions are very similar to an exclusively finite element-based approach, while reducing the number of finite element simulations by a factor of 200.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141308502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fluid jet access in topology optimization for cleanable parts 可清洁部件拓扑优化中的流体喷射通道

IF 4.7 2区工程技术

Computers & Structures Pub Date : 2024-06-08 DOI: 10.1016/j.compstruc.2024.107420

Reinier Giele, Can Ayas, Matthijs Langelaar

引用次数: 0