Thin-Walled Structures最新文献

{"title":"A one-time training machine learning method for general structural topology optimization","authors":"Sen-Zhen Zhan ,&nbsp;Xinhong Shi ,&nbsp;Xi-Qiao Feng ,&nbsp;Zi-Long Zhao","doi":"10.1016/j.tws.2024.112595","DOIUrl":"10.1016/j.tws.2024.112595","url":null,"abstract":"<div><div>Machine learning (ML) methods have found some applications in structural topology optimization. In the existing methods, however, the ML models need to be retrained when the design domains and supporting conditions have been changed, posing a limitation to their wide applications. In this paper, we propose a one-time training ML (OTML) method for general topology optimization, where the self-attention convolutional long short-term memory (SaConvLSTM) model is introduced to update the design variables. An extension–division approach is used to enrich the training sets. By developing a splicing strategy, the training results of a small design space (i.e., a basic cell of either two- or three-dimensions) can be extended to tackling the optimization problem of a large design domain with arbitrary geometric shapes. Using the OTML method, the ML model needs to be trained for only one time, and the trained model can be used directly to solve various optimization problems with arbitrary shapes of design domains, loads, and boundary conditions. In the SaConvLSTM model, the material volume of the post-processed thresholded designs can be precisely controlled, though the control precision of the gray-scale designs might be slightly sacrificed. The effects of model parameters on the computational cost and the result quality are examined. Four examples are provided to demonstrate the high performance of this structural design method. For large-scale optimization problems, the present method can accelerate the structural form-finding process. This study holds a promise in the high-resolution structural form-finding and transdisciplinary computational morphogenesis.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112595"},"PeriodicalIF":5.7,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconfigurable topological gradient metamaterials and potential applications","authors":"Kangkang Chen ,&nbsp;Xingjian Dong ,&nbsp;Zhike Peng ,&nbsp;Guang Meng","doi":"10.1016/j.tws.2024.112572","DOIUrl":"10.1016/j.tws.2024.112572","url":null,"abstract":"<div><div>Elastic topological metamaterials are innovative fields of the fusion of physics and mechanics. Through novel microstructural designs, elastic topological metamaterials provide a pioneering approach to precisely manipulate elastic waves, maintaining robustness and efficiency in wave propagation even within complex environments. Recent advancements in reconfigurability and gradient features have significantly enriched the mechanical phenomena of wave manipulation, broadening the application potential of elastic topological metamaterials. In this study, we design the local resonant phononic crystal, employing a spiral support structure to ensure low-frequency characteristics and adjustable mass for flexible configuration. By utilizing the designed lattices with distinct topological phases, the topological valley edge states are constructed. The frequency and group velocity variation of the topological edge states under different stiffness and mass parameters are analyzed. Furthermore, we further constructed the mass and stiffness gradient metamaterial to analyze the transmission law of elastic waves in topological metamaterials. Additionally, the fluctuation features of the wave transmittance under disordered and impurity defects were discussed, confirming the robustness of waveguides within low-frequency topological metamaterials. Finally, we explored the potential applications of the designed metamaterials in energy localization and low-frequency reconfigurable waveguides. Numerical analysis showed that the topological gradient metamaterials can enhance the vibration energy at a specific interface, and low-frequency bend waveguide paths can be adjusted flexibly by configurable mass. In summary, this paper focuses on the low-frequency and gradient features of elastic topological metamaterials, aiming to unlock their application potential in vibrational energy harvesting, vibration suppression, and information transmission, which accelerate the practical implementation of topological metamaterials.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112572"},"PeriodicalIF":5.7,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142438053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intelligent design of multi-layered variable stiffness composite structure based on transfer learning","authors":"Kunpeng zhang ,&nbsp;Hongjiang Liu ,&nbsp;Shaojun Feng ,&nbsp;Long Li ,&nbsp;Dachuan Liu ,&nbsp;Peng Hao ,&nbsp;Zekai Huo ,&nbsp;Jing Li","doi":"10.1016/j.tws.2024.112588","DOIUrl":"10.1016/j.tws.2024.112588","url":null,"abstract":"<div><div>Variable stiffness composite structures offer more flexible design space than thin-walled metal structures and have greater potential for vibration-resistant design. When faced with multiple new types of design problems, the complex modelling and analysis procedures frequently prove to be both time-consuming and costly in terms of optimization. In this study, an innovative multi-layered variable stiffness (MVS) composite structure with high design flexibility is proposed, with images representation for curvilinearly stiffened paths, non-uniform layouts, and fiber and layup angles. Moreover, an intelligent optimization method based on transfer learning is proposed for addressing a variety of factors affecting dynamic design, including boundary types, structural features, and dynamic responses. The objective of the transfer learning model is to facilitate the inheritance and sharing of variable stiffness features, thereby enabling the efficient design of new problems with limited datasets. The validation of different examples shows that the transfer learning can effectively acquire the structural features from the existing source domain datasets, thereby significantly reducing the data for some new target domains by approximately 50 %. In comparison to the initial constant stiffness (CS) structures, the different optimized configurations indicate that the MVS composite structures are capable of effectively enhancing the dynamic responses by 10 %∼146 % for natural frequency and dynamic compliance. Furthermore, the MVS optimized configuration displays superior dynamic responses in some problems, when compared to the CS optimized configuration.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112588"},"PeriodicalIF":5.7,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Digital image correlation in extreme conditions","authors":"Bo Liu ,&nbsp;Shuzhao Lan ,&nbsp;Jiaqiang Li ,&nbsp;Qihong Fang ,&nbsp;Yiru Ren ,&nbsp;Wei He ,&nbsp;Huimin Xie","doi":"10.1016/j.tws.2024.112589","DOIUrl":"10.1016/j.tws.2024.112589","url":null,"abstract":"<div><div>Digital Image Correlation (DIC) has emerged as a pivotal non-contact, full-field deformation measurement method over the past four decades, witnessing a remarkable expansion in its applications across diverse fields. With the rapid progression of cutting-edge science and technologies, the manufacturing and service environments, as well as the scale and characteristics of critical components are advancing toward extremes. There is an urgent necessity to enhance the DIC method to enable the precise capture of mechanical behaviors and principles under extreme conditions. The difficulties, solutions, and applications of DIC in extreme conditions are herein reviewed, together with a discussion of current limitations and future opportunities.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112589"},"PeriodicalIF":5.7,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cross-sectional zero-dimension temperature model for thin-walled circular tubes in space environment","authors":"Zhe Ma,&nbsp;Zhenxing Shen","doi":"10.1016/j.tws.2024.112591","DOIUrl":"10.1016/j.tws.2024.112591","url":null,"abstract":"<div><div>A sufficiently accurate, yet computationally efficient prediction of temperature field is essential for design of spacecraft structures. This paper presents a model dimension reduction method for thermal analysis of thin-walled circular tubes in space environment, which takes into account radiation heat transfer among the internal surfaces besides heat conduction along the circumferential direction and radiative emission from the external surface. Temperature distribution on the tube cross section is approximated by a series of harmonic functions, so that a one-dimensional problem is reduced to that of zero dimension. The relation between average and perturbation temperatures that depend only on time is broadened to fully coupled one. By comparison to the previous model and the plane finite element model, the accuracy and economy of the new model are illustrated. The results show that internal radiation exchange plays an important role in thermal analysis of thin-walled circular tubes used extensively in spacecraft appendages. Furthermore, differences between present and previous models are analyzed and a two-way analysis of variance is performed to determine the effect of various physical and geometric parameters on the temperature distribution and response of the tubes. The work can be further developed to analyze thermally induced deformation and vibration of spacecraft structures.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112591"},"PeriodicalIF":5.7,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bearing and tearout of austenitic and duplex stainless steel bolted connections","authors":"Yuchen Song ,&nbsp;Xue-Mei Lin ,&nbsp;Michael C.H. Yam ,&nbsp;Yuelin Zhang ,&nbsp;Ke Ke ,&nbsp;Jia Wang","doi":"10.1016/j.tws.2024.112585","DOIUrl":"10.1016/j.tws.2024.112585","url":null,"abstract":"<div><div>Due to the unique material characteristics of stainless steel, the bearing and tearout behaviour of stainless steel bolted connections can be different from that of carbon steel bolted connections. Such difference has been gradually recognised in recent design provisions for stainless steel structures. However, it is noteworthy that the existing design methods were mainly developed for austenitic and ferritic stainless steel bolted connections. Their applicability to duplex stainless steel bolted connections is questionable. Moreover, comparing to the bearing failure of stainless steel connections, less attention has been paid to the tearout failure, as well as the combined bearing and tearout failure in multi-bolt connections. To fill these gaps, an experimental and numerical study is carried out on the bearing/tearout behaviour and design of stainless steel bolted connections. The experimental programme includes 22 connection specimens with either single-bolt or multi-bolt configurations, made of austenitic or duplex stainless steel. The experimental tests are supplemented by a comprehensive numerical parametric study with &gt;200 individual models, performed based on a validated finite element modelling technique. The obtained test and numerical results are used to assess the effects of different design parameters, as well as the applicability of existing design methods. It is concluded that the ultimate bearing/tearout resistances of austenitic and duplex connections are not simply proportionate to the ultimate strengths of the two materials. Given the same geometric design, the bearing resistance of a duplex connection is considerably higher than that of an austenitic connection, despite the similar ultimate strengths of the two materials. This difference in bearing performance is attributed to the different strain-hardening characteristics of austenitic and duplex materials, as well as the premature shear cracking in austenitic connections that leads to insufficiently developed strain-hardening. In comparison, the tearout resistances of austenitic and duplex connections with the same geometry are much closer, since the smaller end distance leads to more uniform deformations and more completely developed strain-hardening. Moreover, the combined bearing and tearout resistance of multi-bolt connections is found to be lower than the sum of the respective resistances of individual bolts. Finally, an updated design method is proposed that can accurately predict the bearing/tearout resistance of both austenitic and duplex stainless steel bolted connections. Proper partial factors are determined for the proposed method based on a reliability analysis.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112585"},"PeriodicalIF":5.7,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of self-centring beam-to-column joints with large-dimensional SMA buckling-restrained plates","authors":"Zhi-Peng Chen,&nbsp;Songye Zhu","doi":"10.1016/j.tws.2024.112586","DOIUrl":"10.1016/j.tws.2024.112586","url":null,"abstract":"<div><div>This paper presents an innovative self-centring (SC) beam-to-column joint (BCJ) design that utilises shape memory alloy (SMA) plates. The proposed SMA-SC-BCJ is constructed through a straightforward approach using large-scale SMA plates to concentrate inelastic deformation and achieve SC capability. This paper first introduces the components and configuration of SMA-SC-BCJ, followed by the development of a refined finite element model for simulations. Validation against previous experiments verifies the model accuracy in capturing joint behaviour. The analysis shows SMA-SC-BCJ exhibits desirable flag-shaped hysteretic behaviours with excellent SC capability, achieving approximately 92 % recovery alongside moderate energy dissipation. Substantial inelastic deformation localises in the SMA fuse plate due to joint rocking, with minimal plastic strain around the rocking centre. Parametric studies on shear element construction, bolt pretension levels and beam gap distances provide additional insights into the joint design. The proposed design meets the objectives for a minimal-damage beam-to-column joint with simple construction. The SMA-SC-BCJ design recommendations are presented on the basis of performance assessments, elucidating the effectiveness of the system. This work contributes an innovative seismic-resistant joint solution that advances the emerging practices towards resilient structures.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112586"},"PeriodicalIF":5.7,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The bending of 3D-printed bio-inspired sandwich panels with wavy cylinder cores","authors":"Xindi Yu ,&nbsp;Qicheng Zhang ,&nbsp;Rodrigo J. da Silva ,&nbsp;Tulio Halak Panzera ,&nbsp;Mark Schenk ,&nbsp;Fabrizio Scarpa","doi":"10.1016/j.tws.2024.112538","DOIUrl":"10.1016/j.tws.2024.112538","url":null,"abstract":"<div><div>Beetle Elytron Plates (BEPs) represent a new class of biomimetic sandwich cores with excellent mechanical properties inspired by the microstructure of the beetle elytra. The cores have a hexagonal centre-symmetric configuration with through-thickness cylinders in the unit cell. In this work, we describe the behaviour of sandwich panels with novel BEP core configurations possessing wavy cylinders under four-point bending tests. Full-scale simulations are also carried out to validate the experimental data. The results show that all the sandwich panels produced with face skins adhesively bonded have material failure earlier than the adhesive bond failure. BEPs with wavy cylinders have larger peak loads compared to those with straight cylinders, and all BEPs show higher peak loads than those of sandwich panels with classical hexagonal honeycombs. Additionally, all the BEPs exhibit an enhanced ductility compared to honeycomb sandwich panels.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112538"},"PeriodicalIF":5.7,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical and numerical predictions of elastoplastic buckling behaviors of the subsea lined pipelines with ovality defects under hydrostatic pressure","authors":"Qian Zhang ,&nbsp;Denglian Yang ,&nbsp;Meiling Shen ,&nbsp;Zhaochao Li","doi":"10.1016/j.tws.2024.112584","DOIUrl":"10.1016/j.tws.2024.112584","url":null,"abstract":"<div><div>The subsea pipelines may deteriorate and/or be cracked after a long period of service. A cost-effective trenchless rehabilitation technology is to install a thin-walled steel liner inside the pipelines. However, elliptical defects may occur in the liner due to issues such as insufficient inflation, deformation of the host pipelines, and joint misalignment in practical engineering. Thus, this study aims to develop a systematic analytical model and numerical model for the elastic and inelastic buckling behaviors of the thin-walled oval steel liner, respectively. An admissible radial displacement function is introduced to describe the single-lobe deformation of the liner. The governing equations are established to trace the equilibrium paths by applying the theory of thin-walled shells and the principle of minimum potential energy. A two-dimensional finite element model is developed for the elastic and inelastic buckling performance of the liner. The analytical solutions of elastic buckling are in good agreement with other closed-form solutions, numerical results, and respective test results available in the literature. Finally, parametric evaluations are carried out in terms of ovality, non-uniform liner-pipeline gap, internal pressure, and liner yield strength.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112584"},"PeriodicalIF":5.7,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An improved modal tracking algorithm for dispersion analysis of arbitrary prestressed plates","authors":"Xu Zhang,&nbsp;Lei Chen,&nbsp;Gang Liu,&nbsp;Zehui Zhang,&nbsp;Jiachen Wang","doi":"10.1016/j.tws.2024.112582","DOIUrl":"10.1016/j.tws.2024.112582","url":null,"abstract":"<div><div>Determining the dispersion characteristics of prestressed plates is essential for guided wave-based structural health monitoring, which can provide theoretical guidance for optimizing excitation mode and frequency. However, the multi-mode nature of guided waves brings huge challenges for modal tracking. Conventional methods require sufficiently small frequency steps and may encounter tracking errors during mode crossing and overlap. To address these issues, this paper established a multi-step superposition model to obtain the dispersion relation of arbitrary prestressed plates and proposed a novel modal tracking method based on structural similarity (SSIM) image registration for identifying all guided wave modes. Drawing inspiration from the image quality assessment technique, a novel index was introduced to evaluate the consistency between modal eigenvectors quantitatively. Furthermore, an improved algorithm using eigenvector operations was developed to further enhance the efficiency and applicability of the modal tracking process. Subsequently, application examples were conducted to thoroughly evaluate the performance of the proposed methods through comparison with conventional modal tracking methods. The results indicated that the proposed methods have accurate and reliable tracking performance even with larger wavenumber steps, which is unattainable with conventional methods. Notably, the computational efficiency of the improved algorithm is nearly 13 times faster than the SSIM-based image registration method. Finally, an investigation into the dispersion characteristics of aluminum plates under tensile, bending, and shear stress demonstrated the versatility of the improved modal tracking algorithm. This study provides valuable insights into the dispersion behavior of guided waves in prestressed plates.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"205 ","pages":"Article 112582"},"PeriodicalIF":5.7,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}