Latin American Journal of Solids and Structures最新文献_第2页

A Multiobjective Optimization Framework for Strength and Stress Concentration in Variable Axial Composite Shells: A metaheuristic approach 可变轴向复合材料壳体强度和应力集中的多目标优化框架:一种元启发式方法

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-07-17 DOI: 10.1590/1679-78257577

P. Santana, H. Gomes, A. Ferreira, V. Tita

{"title":"A Multiobjective Optimization Framework for Strength and Stress Concentration in Variable Axial Composite Shells: A metaheuristic approach","authors":"P. Santana, H. Gomes, A. Ferreira, V. Tita","doi":"10.1590/1679-78257577","DOIUrl":"https://doi.org/10.1590/1679-78257577","url":null,"abstract":"A metaheuristic approach for variable axial composites considering multiobjective optimization is investigated. The proposed methodology is based on the combination of three main parts: a methodology for defining the orientation of the fibers in the laminate, a structural analysis program (based on the Finite Element Method) and an optimization algorithm. It is important to highlight that a radial basis function (RBF), which describes a smooth fiber pattern, is generated using control points. The novelties of the present methodology consist of a proposal for a generalized parameterization technique, which allows the investigation of mechanical strength and stress concentration of variable axial composites. Thus, NSGA-II multiobjective genetic algorithm is used as optimization tool to define the fiber orientations. Besides, ax metaheuristic approach is used in situations when it is desirable to simultaneously minimize the stress concentration factor ( 𝐾𝐾 𝑡𝑡 ) and a failure criterion index ( 𝐹𝐹𝐹𝐹 or Φ ). Two case studies are investigated: a double notched plate and a tube with a transverse hole.","PeriodicalId":18192,"journal":{"name":"Latin American Journal of Solids and Structures","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67624388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Optimization of Vibration Band Gaps in Damped Lattice Metamaterials 优化阻尼晶格超材料的振动带隙

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-07-17 DOI: 10.1590/1679-78257486

Rubens Gonçalves Salsa Junior, T. P. Sales, D. Rade

{"title":"Optimization of Vibration Band Gaps in Damped Lattice Metamaterials","authors":"Rubens Gonçalves Salsa Junior, T. P. Sales, D. Rade","doi":"10.1590/1679-78257486","DOIUrl":"https://doi.org/10.1590/1679-78257486","url":null,"abstract":"Recent research on structural dynamics has steered towards elastic metamaterials, as band gap phenomena can be explored to mitigate vibration. A challenge in their design is the determination of configurations resulting in wider band gaps in lower frequency ranges. Since some level of damping is unavoidable in any real engineering structure, it is necessary to extend the current methodology of optimal design to provide a deeper understanding of how damping may affect the desired performance. Therefore, the main objective of this article is to propose and evaluate a numerical procedure for the optimization of band gaps in damped metamaterials. Specifically, a modified objective function that incorporates an evanescence index integral is used and two optimization schemes are implemented, each reflecting whether the structure is undamped or damped. It is shown that the optimal damped metamaterial has wider range of attenuation than the undamped optimal one, but with decreased attenuation levels. The optimization procedure is validated numerically for a finite structure, demonstrating reduced transmissibility of wave motions.","PeriodicalId":18192,"journal":{"name":"Latin American Journal of Solids and Structures","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139358528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Dynamic response of piled structures including pile-soil-pile interaction 桩结构的动力响应包括桩-土-桩相互作用

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-07-07 DOI: 10.1590/1679-78257514

Amanda Oliveira, A. Vasconcelos, J. Labaki

{"title":"Dynamic response of piled structures including pile-soil-pile interaction","authors":"Amanda Oliveira, A. Vasconcelos, J. Labaki","doi":"10.1590/1679-78257514","DOIUrl":"https://doi.org/10.1590/1679-78257514","url":null,"abstract":"This article presents a numerical model and analyses of the dynamic response of structures supported by groups of piles. The model uses a finite element discretization to represent arbitrarily-shaped structures, and a coupled finite-boundary element scheme to represent the embedded pile group. This scheme properly takes into account the energy transferred from the structure to the piles and between piles through the soil, so that the effect of dynamic pile–soil–pile interaction in the response of the structure can be studied. The model is used to analyze the dynamic response of a wind turbine tower and foundation blocks of various designs. The results show that some common design approximations may result in considerable misrepresentation of the response of these structures. The model is also used to analyze cases in which the only source of excitation to a structure comes through the soil from neighboring structures. The results showed that the farther the structure is from the source of vibration, the lower its amplitude of vibration and that the taller the structure, the lower its resonant frequencies. These analyses are only possible with models like the one presented in this article, which are able to describe the energy exchanged through the soil by the piles in a group.","PeriodicalId":18192,"journal":{"name":"Latin American Journal of Solids and Structures","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67623815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Comparative evaluation of design codes for buckling assessment of a steel spherical shell 钢球壳屈曲评定设计规范的比较评价

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-07-07 DOI: 10.1590/1679-78257473

M. Ismail, J. Mahmud

{"title":"Comparative evaluation of design codes for buckling assessment of a steel spherical shell","authors":"M. Ismail, J. Mahmud","doi":"10.1590/1679-78257473","DOIUrl":"https://doi.org/10.1590/1679-78257473","url":null,"abstract":"This work focuses on the comparative evaluation of the buckling capacity of steel spherical shells subjected to external pressure with existing design codes. The recorded experimental data of buckled spherical shells are compared with the calculated buckling pressure using design codes such as (i) European Convention for Constructional Steelwork (ECCS), (ii) Det Norske Veritas (DnV), (iii) British Standard (PD 5500) and (iv) American Bureau of Shipping (ABS). The selected experimental data are widely used in industrial applications. The experimental data are categorised as 'thin-shell', 'moderate-shell' and 'thick-shell' and reviewed against selected design codes. The comparative analysis clearly shows that the DnV design code with a deviation of 3.6% is well suited to estimate the buckling capacity of 'thick shells\", while PD 5500 with a deviation of 9% to 50% is better suited for \"medium and thin' shells. On the other hand, statistical analysis shows that PD 5500 is close to 1.0 with the value of COV (i.e., 1.281 and 9.383%). Further analysis of 28 steel spherical shell test data is performed and compared with the plotted curves in the format of PD 5500 and ECCS. The result shows that 3 test data are below the lower limit curve specified in the design guideline for ECCS, indicating that PD 5500 is the more conservative design guideline.","PeriodicalId":18192,"journal":{"name":"Latin American Journal of Solids and Structures","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67623947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Fault Diagnosis of Motor Bearing Based on Current Bi-Spectrum and Convolutional Neural Network 基于当前双谱和卷积神经网络的电机轴承故障诊断

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-06-26 DOI: 10.1590/1679-78257364

Jiaojiao Ma, Lingli Jiang, Shuhui Li, Heshan Sheng, Chengxi Zhou, Xuejun Li

{"title":"Fault Diagnosis of Motor Bearing Based on Current Bi-Spectrum and Convolutional Neural Network","authors":"Jiaojiao Ma, Lingli Jiang, Shuhui Li, Heshan Sheng, Chengxi Zhou, Xuejun Li","doi":"10.1590/1679-78257364","DOIUrl":"https://doi.org/10.1590/1679-78257364","url":null,"abstract":"Motor bearings are prone to different degrees of performance degradation, fatigue damage and failure undergoing complex and harsh environments. Vibration signal analysis is a mature method for diagnosing motor bearing faults, while it is not applicable for installing additional vibration sensors on many occasions. Practically, the fault of motor bearings changes the air gap flux between the rotor and stator, which leads to harmonic fluctuations in the stator current. The current signals can be used to diagnose the motor bearing faults without additional sensors. Inevitably the harmonics caused by the motor bearing faults will be coupled with the original signals. This paper combines bi-spectrum and Convolution Neural Network (CNN) to analyze the current signals of motor bearing faults. The CNN diagnosis model is trained based on the local bi-spectrum of current, and the CNN parameters are optimized. Diagnose and analyze motor bearing faults with different fault implantation methods, working conditions, fault degrees and fault locations. The diagnostic accuracy reaches more than 80%.","PeriodicalId":18192,"journal":{"name":"Latin American Journal of Solids and Structures","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67622917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Innovated shear deformable FE formulations for the analyses of steel beams strengthened with orthotropic GFRP laminates 创新的剪切变形有限元公式，用于分析用正交各向异性玻璃钢加强的钢梁

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-05-29 DOI: 10.1590/1679-78257549

T. Bui-Tien, Phe Van Pham

{"title":"Innovated shear deformable FE formulations for the analyses of steel beams strengthened with orthotropic GFRP laminates","authors":"T. Bui-Tien, Phe Van Pham","doi":"10.1590/1679-78257549","DOIUrl":"https://doi.org/10.1590/1679-78257549","url":null,"abstract":"The present study develops an innovated shear deformable theory and four finite element formulations based on a total potential energy variational principle for the analysis of steel beams strengthened with GFRP laminates. The present theory captures orthotropic properties of the GFRP laminae, GFRP lamina stacking sequences, partial interaction between the steel beam and the GFRP laminates, and shear deformations. Three examples are conducted for the validation of the present theory. Through comparisons, the system responses predicted by the present solutions are excellently validated against those of recent experimental studies and three-dimensional finite element analyses. Key results obtained in the present study include: (i) the responses of GFRP-strengthened beams are strongly influenced by GFRP fiber angle arrangements. (ii) The strengthening is the most effective for steel beams strengthened with a GFRP laminate stacked with fiber angles of 0 degree. Based on two parametric studies, the effects of the orthotropic GFRP lamina properties and GFRP laminate thicknesses on the system deflections are also investigated","PeriodicalId":18192,"journal":{"name":"Latin American Journal of Solids and Structures","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67624120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Numerical analysis of fluid-body interaction considering vortex and tornado-like flows 考虑旋涡和类龙卷风流动的流-体相互作用数值分析

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-05-29 DOI: 10.1590/1679-78257419

M. Aguirre, A. L. Braun, A. M. Awruch

引用次数: 0

Numerical model for analysis of compact and slender hybrid steel beams subjected to bending 弯曲作用下紧凑和细长混合钢梁的数值分析模型

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-05-29 DOI: 10.1590/1679-78257411

Caroline Martins Calisto, A. L. C. E. Silva, R. Caldas, H. Carvalho

引用次数: 0

Mechanical and Energy-Absorption Properties of a 3D-Printed Star-Shaped Auxetic Honeycomb under Combined Compression-Shear Loading 压缩-剪切复合载荷下3d打印星形辅助蜂窝的力学和吸能特性

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-05-19 DOI: 10.1590/1679-78257624

Geng Luo, Duanyu Mo, Chen-Ket Chai, Jun-Zhong Liu, Yisong Chen

{"title":"Mechanical and Energy-Absorption Properties of a 3D-Printed Star-Shaped Auxetic Honeycomb under Combined Compression-Shear Loading","authors":"Geng Luo, Duanyu Mo, Chen-Ket Chai, Jun-Zhong Liu, Yisong Chen","doi":"10.1590/1679-78257624","DOIUrl":"https://doi.org/10.1590/1679-78257624","url":null,"abstract":"In this study, we investigated the mechanical and energy-absorption properties of a star-shaped auxetic honeycomb under combined compression-shear loading. Novel fixtures were designed to conduct quasi-static combined compression-shear loadings. Experimental and numerical results show that the honeycomb undergoes an overall deformation based on cell rotation under quasi-static loading, producing an inclined deformation band. The normal yield stress decreased, and the shear yield stress increased with an increase in the loading angle. The extrusion deformation between meso-structures became more sufficient under dynamic combined loadings. The material deformation mode changed from overall deformation to local deformation accompanied by the formation of a shock wave. The yield criteria were established based on the ellipse equation. With an increase in the loading angle, the energy absorption in the normal and shear directions of the materials showed downward and upward trends, respectively. A theoretical model was proposed based on the 1D shock wave model to predict the energy-absorption behaviour under dynamic loading","PeriodicalId":18192,"journal":{"name":"Latin American Journal of Solids and Structures","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67624885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Optimizing stiffness and lightweight design of composite monocoque sandwich structure for electric heavy quadricycle 电动重型四轮车单壳夹层复合结构刚度优化及轻量化设计

IF 1.2 4区工程技术

Latin American Journal of Solids and Structures Pub Date : 2023-05-08 DOI: 10.1590/1679-78257537

Thonn Homsnit, Suphanut Kongwat, K. Ruangjirakit, Paphatsorn Noykanna, Thittipat Thuengsuk, P. Jongpradist

{"title":"Optimizing stiffness and lightweight design of composite monocoque sandwich structure for electric heavy quadricycle","authors":"Thonn Homsnit, Suphanut Kongwat, K. Ruangjirakit, Paphatsorn Noykanna, Thittipat Thuengsuk, P. Jongpradist","doi":"10.1590/1679-78257537","DOIUrl":"https://doi.org/10.1590/1679-78257537","url":null,"abstract":"The lightweight design of electric heavy quadricycle (L7e) vehicles has contributed to energy savings and sustainable mobility. This study proposes an optimization methodology to design a monocoque sandwich structure under operating conditions for an L7e using a finite element model via HyperWorks. Woven fiberglass fabrics and high-density PVC foam are assigned as the face and core to construct the sandwich structure, respectively. Free-size optimization based on weight minimization is applied to obtain the suitable initial thickness of face and core structures in all components. Multi-objective size optimization is then performed by minimizing both mass and material cost to determine the optimal thickness of each layer. Finally, shuffle optimization is used to modify the stacking sequence for each component to maximize structural stiffness. The results indicate that the core thickness in the passenger compartment is sufficient to maintain stiffness while maintaining the structure's lightweight. However, shuffle optimization is insignificant for the current monocoque model, as the structural stiffness is only marginally improved after the process. Additionally, this study examines the optimized models for structural stiffness and discusses suitable procedures for designing a lightweight and safe electric vehicle.","PeriodicalId":18192,"journal":{"name":"Latin American Journal of Solids and Structures","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67623846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 1