Computers & Structures最新文献

Exact energy harvesting analysis of multimodal piezoelectric beams using the dynamic stiffness method

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-06 DOI: 10.1016/j.compstruc.2025.107746

Xiang Liu , Yu Wang , Sondipon Adhikari , Weixian Zhou

{"title":"Exact energy harvesting analysis of multimodal piezoelectric beams using the dynamic stiffness method","authors":"Xiang Liu , Yu Wang , Sondipon Adhikari , Weixian Zhou","doi":"10.1016/j.compstruc.2025.107746","DOIUrl":"10.1016/j.compstruc.2025.107746","url":null,"abstract":"<div><div>Piezoelectric vibration energy harvesting holds great potential for converting ambient vibrations into electrical energy. Establishing a suitable theoretical model to predict the performance of piezoelectric harvesters under base excitation is essential. This paper proposes a dynamic stiffness (DS) modeling technique to predict the electromechanical coupling responses of piezoelectric beams. The modeling technique is sufficiently general to be applied to a wide range of simple cantilever or generally complex piezoelectric beam structures. For demonstration purposes, this technique is applied to model beams equipped with three typical tip attachments and connected to three representative external circuits, enabling a comprehensive multimodal analysis. The Wittrick–Williams (WW) algorithm is employed to efficiently calculate the eigenvalues of DS matrices with any desired accuracy. This aids in tuning the natural frequency of piezoelectric beams to match the ambient environmental vibration frequency. The concepts of electrically-induced stiffness and electrically-induced damping are introduced to characterize the impact of energy harvesting circuits on natural frequencies and output voltage of piezoelectric harvesters. Theoretical research specifically conducted on piezoelectric beams explores the effects of material parameters, structural dimensions, load resistance, and base excitation on vibration energy harvesting. Finite element simulation confirms that the proposed DS model, based on the exact solution of governing differential equations, can accurately and effectively predict the output performance of piezoelectric harvesters. The proposed method can emerge as a powerful tool for the design and optimization of piezoelectric energy harvesters.</div></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":"313 ","pages":"Article 107746"},"PeriodicalIF":4.4,"publicationDate":"2025-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783545","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

Mathematical and numerical analysis of local buckling thin-walled beams with non-standard cross-sections

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-05 DOI: 10.1016/j.compstruc.2025.107752

Aleksandra M. Pawlak, Piotr Paczos, Michał Grenda, Tomasz A. Górny, Marcin Rodak

{"title":"Mathematical and numerical analysis of local buckling thin-walled beams with non-standard cross-sections","authors":"Aleksandra M. Pawlak, Piotr Paczos, Michał Grenda, Tomasz A. Górny, Marcin Rodak","doi":"10.1016/j.compstruc.2025.107752","DOIUrl":"10.1016/j.compstruc.2025.107752","url":null,"abstract":"<div><div>The paper presents a novel approach to the analysis of buckling in thin-walled steel beams with modified cross-sectional shapes, focusing on their behavior under four-point bending. The aim of the study was to develop and examine new methods for determining critical loads for structural members with non-standard cross-sectional shapes, which are innovative in themselves. These methods are based on theoretical solutions grounded in the principle of potential energy conservation (an original approach). Additionally, based on the derived mathematical formulas, a custom application was developed, enabling rapid determination of critical loads using these new theoretical methods. The results show that the modified cross-sections significantly improve the mechanical properties of the beams, increasing their stiffness, buckling resistance, and load-bearing capacity. The findings provide new insights that can contribute to optimizing the design of thin-walled structures, with practical applications in the construction and automotive industries. The Finite Strip Method was used to verify the obtained results.</div></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":"313 ","pages":"Article 107752"},"PeriodicalIF":4.4,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776977","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

Introducing material-specific stress constraints in multi-material topology optimization

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-05 DOI: 10.1016/j.compstruc.2025.107756

Abolfazl Yaghoobi, Mohsen Asghari, Hossein Babaei

{"title":"Introducing material-specific stress constraints in multi-material topology optimization","authors":"Abolfazl Yaghoobi, Mohsen Asghari, Hossein Babaei","doi":"10.1016/j.compstruc.2025.107756","DOIUrl":"10.1016/j.compstruc.2025.107756","url":null,"abstract":"<div><div>Multi-material topology optimization has emerged as a powerful design tool, enabling the integration of different material properties to enhance structural performance. A critical challenge in applying stress constraints to multi-material structures is that each material has a distinct stress limit that must not be exceeded. Conventional approaches typically address this by enforcing a single stress limit for all materials or using interpolation functions, both of which introduce limitations and additional complexities. In contrast, we propose a material-specific stress constraint method that treats each material separately. The stress in each material is computed individually and directly compared to its respective stress limit, eliminating the need for additional interpolation functions. Furthermore, the stress singularity phenomenon is naturally avoided without requiring relaxation techniques. To solve the optimization problem, an image regeneration approach based on CNN is employed. A projection filter is developed that strictly enforces the mass constraint while ensuring a valid material distribution. The method is evaluated through three numerical examples, demonstrating the impact of stress constraints on the minimum compliance problem. The results show a significant reduction in stress levels, in exchange for a small increase in compliance, while ensuring that the stress in all materials remains within their respective limits.</div></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":"313 ","pages":"Article 107756"},"PeriodicalIF":4.4,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776976","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

Compatible strain-based upper bound limit analysis model for masonry walls under in-plane loading

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-05 DOI: 10.1016/j.compstruc.2025.107743

Nicola Grillanda, Vincenzo Mallardo

{"title":"Compatible strain-based upper bound limit analysis model for masonry walls under in-plane loading","authors":"Nicola Grillanda, Vincenzo Mallardo","doi":"10.1016/j.compstruc.2025.107743","DOIUrl":"10.1016/j.compstruc.2025.107743","url":null,"abstract":"<div><div>We present a novel numerical model for the upper bound limit analysis of in-plane loaded masonry structures. The construction is represented as a continuum model composed of planar elements whose kinematics combines rigid body velocities and plastic strain rates. The global velocity field remains continuous and crack configurations are described via plastic strain rates. Homogenization ensures the compatibility between the continuum’s plastic strain rate field and the kinematics of the heterogeneous material: idealizing masonry as an assembly of rigid bricks and frictional zero-thickness joints, the associative flow rule is expressed through homogenized kinematic relations defining a domain of compatible plastic strain rates. The derived limit analysis problem is written as a linear programming problem, yielding an upper bound of the load-bearing capacity along with rigid body velocities and a compatible plastic strain rate field. Finally, a local mesh refinement strategy governed by the <span><math><msub><mrow><mi>L</mi></mrow><mn>2</mn></msub></math></span>-norm of plastic strain rates optimizes the mechanism representation. The presented formulation offers advantages over the conventional homogenized limit analysis methods by defining a failure domain via strain rates, rather than stress, providing a more compact and computationally efficient numerical approach. Its efficacy is proven through numerical examples and comparisons with well-established analytical and numerical models.</div></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":"313 ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776611","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

Investigation of existing and new approaches to step size control in a continuation framework

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-04 DOI: 10.1016/j.compstruc.2025.107747

Tido Kubatschek, Alwin Förster

引用次数: 0

Hierarchical element integration technique in discrete element simulation of rock failure

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-04 DOI: 10.1016/j.compstruc.2025.107757

Zhiyang Wang , Mengyi Li , Mengli Li , Zhijun Wu , Fengshou Zhang , Yingwei Li

{"title":"Hierarchical element integration technique in discrete element simulation of rock failure","authors":"Zhiyang Wang , Mengyi Li , Mengli Li , Zhijun Wu , Fengshou Zhang , Yingwei Li","doi":"10.1016/j.compstruc.2025.107757","DOIUrl":"10.1016/j.compstruc.2025.107757","url":null,"abstract":"<div><div>Discrete element method has a congenital advantage over the continuous numerical methods for simulating the damage and fracture of geo-materials, as its calculation principles align with the discontinuous nature of these materials. Due to the unclear relationship between element scale and element strength (size effect), the element parameters, especially for the field-scale model, are quite hard to be reasonably determined, causing computational efficiency and accuracy cannot be balanced. To address this issue, the hierarchical scaling size effect model was developed to characterize the relationship between the strength and size of rock material. Based on which, an element integration technique was proposed that achieves a match between element strength and size. Discrete element simulations of laboratory tests demonstrated that, compared to the grain-based model (GBM), the calculation accuracy is maintained while the number of elements can be reduced by 2 to 3 orders of magnitude, indicating more than 100-fold improvement in calculation efficiency. This element integration technique was also employed in the simulation of field-scale hydraulic fracturing to demonstrate its feasibility in capturing the failure evolution in rock mass from a few centimeters to tens meters. Additionally, the mechanism of fault slip induced by hydraulic fracturing was roughly discussed.</div></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":"313 ","pages":"Article 107757"},"PeriodicalIF":4.4,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768572","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

Multi-scale concurrent topology optimization of lattice structures with single type of composite micro-structure subjected to design-dependent self-weight loads

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-03 DOI: 10.1016/j.compstruc.2025.107755

Minh Ngoc Nguyen , Duy Vo , Chanh Dinh Vuong , Tinh Quoc Bui

{"title":"Multi-scale concurrent topology optimization of lattice structures with single type of composite micro-structure subjected to design-dependent self-weight loads","authors":"Minh Ngoc Nguyen , Duy Vo , Chanh Dinh Vuong , Tinh Quoc Bui","doi":"10.1016/j.compstruc.2025.107755","DOIUrl":"10.1016/j.compstruc.2025.107755","url":null,"abstract":"<div><div>This paper presents a computational framework for compliance-based multi-scale concurrent topology optimization including self-weight. The macro-scale structure consists of periodically arranged composite micro-structures, such that the representative unit cell of each micro-structure is composed of multiple base-materials, instead of single base-material as usually encountered in the literature. The effective elastic tensor of the micro-structure is evaluated using the strain energy method (SEM), which is incorporated with a mapping based interpolation scheme for multiple underlying materials. Sensitivity analysis is executed in both macro-scale and micro-scale, providing the gradient information for updating the design variables using the method of moving asymptotes (MMA). The undesirable phenomena related to the design-dependent self-weight load are observed, including the parasitic effect and the inactive volume constraint. When the self-weight load is dominant over the external fixed loads, especially in the case of pure self-weight, the optimizer tends to remove material to reduce self-weight, and thus reduces the structural compliance. This phenomenon, which is referred as inactive volume constraint in the literature, occurs at both scales. On the other hand, the parasitic effect, which is the appearance of erratic intermediate density patterns, occurs only in the macro-structure but not in the micro-structure. Discussion on possible treatments for these numerical issues is provided. Several numerical examples of 2D structures are examined to demonstrate the feasibility and performance of the developed method.</div></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":"313 ","pages":"Article 107755"},"PeriodicalIF":4.4,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761055","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

Enhanced generalized subset simulation with multiple importance sampling for reliability estimation

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-03 DOI: 10.1016/j.compstruc.2025.107741

Weili Xia , Zihan Liao

引用次数: 0

Introducing large-scale multiphysics topology optimization for electric aircraft battery pack design

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-01 DOI: 10.1016/j.compstruc.2025.107748

Alexandre T.R. Guibert , Murtaza Bookwala , Matteo Pozzi , H. Alicia Kim

{"title":"Introducing large-scale multiphysics topology optimization for electric aircraft battery pack design","authors":"Alexandre T.R. Guibert , Murtaza Bookwala , Matteo Pozzi , H. Alicia Kim","doi":"10.1016/j.compstruc.2025.107748","DOIUrl":"10.1016/j.compstruc.2025.107748","url":null,"abstract":"<div><div>Electric Vertical Take-Off and Landing (eVTOL) vehicles hold great promise for mitigating traffic congestion and the performance of eVTOL battery packs plays a crucial role in advancing this mode of transportation. This paper introduces a methodology for optimizing eVTOL battery packs, employing level-set topology optimization while accounting for multiphysics loads to achieve a lightweight structure that is thermally and structurally efficient. A beam model at the system level simulates the boom hosting the battery pack, determining the mechanical load borne by the battery pack and an electrochemical model predicts the batteries’ maximum heat generation given a mission profile. These contributions serve as inputs for the thermo-mechanical battery pack model. The workflow is exemplified with a battery module comprising seven battery cells with the objective of minimizing thermal and structural compliances while exploring the trade-off between these two factors. Subsequently, the model is expanded to optimize the entire boom structure. The model, with over 50 million degrees of freedom, is solved using distributed memory parallelism to minimize structural compliance while adhering to volume, stress, and temperature constraints. This study demonstrates the application of large-scale multiphysics optimization in designing battery packs, facilitating the development of lightweight electric aircraft.</div></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":"313 ","pages":"Article 107748"},"PeriodicalIF":4.4,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740077","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

Large displacement analysis of masonry structures coupling enhanced virtual elements and damage-friction interfaces

IF 4.4 2区工程技术

Computers & Structures Pub Date : 2025-04-01 DOI: 10.1016/j.compstruc.2025.107749

Cristina Gatta , Marco Nale , Daniela Addessi , Elena Benvenuti , Elio Sacco

{"title":"Large displacement analysis of masonry structures coupling enhanced virtual elements and damage-friction interfaces","authors":"Cristina Gatta , Marco Nale , Daniela Addessi , Elena Benvenuti , Elio Sacco","doi":"10.1016/j.compstruc.2025.107749","DOIUrl":"10.1016/j.compstruc.2025.107749","url":null,"abstract":"<div><div>Enhanced virtual elements are coupled with cohesive interfaces to create a numerical tool tailored for large displacement analysis of block structures. The model is particularly suitable for masonry composed of stones or bricks connected with or without mortar. Each masonry block is modeled with a single elastic virtual element (VE), based on a divergence-free polynomial approximation of the stress field within the element, and the corotational formulation recently developed by the authors. These stabilization-free VEs are coupled, for the first time, with damaging-frictional interfaces representing the layers interconnecting the blocks, which are innovatively extended to the large displacement framework. Furthermore, in the context of virtual elements, a novel method is presented to accurately evaluate nodal forces equivalent to body loads when internal degrees of freedom are not available.</div><div>Some numerical applications are performed to investigate the capability of the proposed formulation to reproduce the response of single masonry elements and more complex structural schemes. The analyses prove that the model reproduces well the main nonlinear mechanisms due to the presence of large displacements and material degradation caused by cracking and friction. Finally, the model potential to handle irregular stone walls is proved through numerical–experimental comparison.</div></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":"313 ","pages":"Article 107749"},"PeriodicalIF":4.4,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740078","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