Engineering Structures最新文献

{"title":"Dynamic behavior analysis of the wheel-rail impact mitigation device for fixed frog gaps incorporating rubber's strain rate dependency","authors":"Jiaxin Lei ,&nbsp;Dongshi Wang ,&nbsp;Xinhao Zhang ,&nbsp;Caiyou Zhao ,&nbsp;Ping Wang ,&nbsp;Changsheng Zhou ,&nbsp;Hualong Zhou","doi":"10.1016/j.engstruct.2025.120614","DOIUrl":"10.1016/j.engstruct.2025.120614","url":null,"abstract":"<div><div>The wheel-rail interaction at the gap in the frog of fixed turnouts is characterized by discontinuous contact traces and nonlinear geometric profiles, which often induce transient impact vibrations with broad frequency ranges and significant amplitudes. This study develops a Wheel-Rail Impact Mitigation Device (WRIMD) through a combination of theoretical modeling and field testing. The aim is to address the discontinuity in contact traces and promote uniform distribution of wheel-rail forces. A transient rolling contact model for a 50 kg/m rail No. 9 turnout, integrating the bogie and frog, was constructed using the participating mass method, with computational efficiency enhanced through a hybrid Lagrangian-Eulerian approach. To address challenges in the definition of impact index parameters, this study introduced the concept of effective impact energy probability, providing a comprehensive framework for characterizing both global and instantaneous wheel-rail impact phenomena at the frog. The study identified the abrupt transition between single-point and multi-point wheel-rail contact at the gap as the primary driving mechanism for impact vibrations. The WRIMD has a dual-layer design, with an upper impact-resistant layer made of manganese steel and a lower damping layer made of rubber. Considering transient wheel-rail impact dynamics, a hyper-viscoelastic constitutive model for the rubber material was formulated by incorporating the relationship between impact velocity and strain rate. The optimal height of the damper was determined through a combined quasi-static and dynamic analysis. Simulation results indicated a 5.57 % reduction in the impact index and a 23.9 % decrease in total impact energy when the damper was implemented. Safety assessments under extreme operational conditions confirmed that the damper met all operational safety standards. Field installation of the damper, secured by bolting and adhesive bonding, demonstrated that it effectively reduced medium- and high-frequency vibrations above 100 Hz, with measured reductions of approximately 9 dB in frog vibration and 6 dB in sleeper vibration. This research further reveals vibration isolation in turnout substructures and presents an innovative solution for the management of transient wheel-rail impacts in fixed frogs.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120614"},"PeriodicalIF":5.6,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125222","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":"A generalised framework for designing topological interlocking structures from monomorphic elements","authors":"Siya Wang ,&nbsp;Xiaoshan Lin ,&nbsp;Y.X. Zhang ,&nbsp;Yi Min Xie","doi":"10.1016/j.engstruct.2025.120607","DOIUrl":"10.1016/j.engstruct.2025.120607","url":null,"abstract":"<div><div>Topological interlocking (TI) structures, known for their superior energy dissipation, damage tolerance, and adaptability, are gaining increasing attention as innovative solutions to advanced structural designs. In this study, a general framework is developed for designing TI elements with curved contact surfaces, enabling the creation of monomorphic elements through a matched concavo-convex interface. The element shapes are controlled by parameters such as polygon type, polygon length, curve function, and element thickness. This approach can be applied to designing TI elements for both planar and non-planar structures. Validation is achieved through the design of 24 planar and 12 non-planar TI elements, along with two 3D-printed prototypes. Furthermore, the impact performance of typical TI plates is compared to that of a monolithic structure to demonstrate the effectiveness of the generalised interlocking mechanism.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120607"},"PeriodicalIF":5.6,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125231","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":"A transfer learning-based framework for acoustic emission source localization of real cracks in reinforced concrete","authors":"Shuo Wang ,&nbsp;Wenxi Wang ,&nbsp;Donghuang Yan ,&nbsp;Guokun Liu ,&nbsp;Lidong Zhang ,&nbsp;Xugang Hua","doi":"10.1016/j.engstruct.2025.120628","DOIUrl":"10.1016/j.engstruct.2025.120628","url":null,"abstract":"<div><div>Deep learning models have emerged as a promising solution for acoustic emission (AE) source localization, offering adaptability to composite materials like reinforced concrete. However, existing deep learning models often rely on AE data from simulated sources, such as pencil lead breakage or ball impact, which may not accurately represent real cracks, thereby limiting the performance of deep learning models. This paper proposes a novel deep learning model based on transfer learning for AE source localization of real cracks in reinforced concrete components. The proposed model consists of a source model and a target model, both built with a 1-dimensional convolutional neural network (CNN) and fully connected layers. The source model is trained on a simulated AE dataset, and its 1-dimensional CNN is transferred to the target model. The target model is then fine-tuned using limited AE data from real cracks collected during a four-point bending test. The trained model locates AE sources from real cracks by outputting a grid-based probability map. The performance of the model was compared with and without transfer learning. Additionally, the robustness of the proposed model against noise was investigated through field testing on a real bridge. The generalization performance on unseen reinforced concrete components was also examined. Additionally, t-distributed stochastic neighbor embedding was used to analyze the interpretability. The results indicate the effectiveness of the proposed model in AE source localization of real cracks in reinforced concrete components. Additionally, the model remains robust under noisy conditions, indicates its effectiveness in practical AE source localization applications.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120628"},"PeriodicalIF":5.6,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125232","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":"Flexural fatigue strength of RC bridge girders strengthened by PHSW-PM","authors":"Qunxian Huang ,&nbsp;Yang Liu ,&nbsp;Zixiong Guo ,&nbsp;Jiann-Wen Woody Ju","doi":"10.1016/j.engstruct.2025.120640","DOIUrl":"10.1016/j.engstruct.2025.120640","url":null,"abstract":"<div><div>A novel method for enhancing the flexural fatigue strength of reinforced concrete (RC) bridge girders is presented. This method adopts externally attached prestressed high-strength steel wires covered by polymer mortar, referred to as PHSW-PM. To evaluate the effectiveness and applicability of this technique, monotonic and fatigue tests were conducted on RC beam specimens subjected to repeated load cycles within service load ranges. The investigation focused on four main parameters: the loading condition, the prestressing level of the high-strength steel wires, the anchorage condition, and the bond properties between the polymer mortar and the concrete surface. The RC specimens strengthened with PHSW-PM demonstrated exceptional performance under fatigue loading, withstanding over two million repeated load cycles without failure. The test results revealed that a higher level of prestressing force in the steel wires significantly enhances the crack resistance of the strengthened beams. Additionally, the bond interface condition between the polymer mortar layer and the concrete surface, along with the type of anchorage, were identified as critical factors influencing the flexural fatigue capacity and ductility of the strengthened beams. Based on the experimental results, an empirical design formula has been derived to evaluate the flexural fatigue capacity of beams strengthened using the PHSW-PM methodology. This study provides valuable insights into the potential of PHSW-PM as an effective technique for improving the structural performance of RC bridge girders under cyclic loading conditions.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120640"},"PeriodicalIF":5.6,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125229","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":"A virtual joints based transfer matrix method for dynamic performance analysis of periodic beams","authors":"He Zhang ,&nbsp;Yihui Guo ,&nbsp;Tengxin Lin ,&nbsp;Kun Xue","doi":"10.1016/j.engstruct.2025.120374","DOIUrl":"10.1016/j.engstruct.2025.120374","url":null,"abstract":"<div><div>An updated Transfer Matrix (TM) method involving spatial discretization through the introduction of virtual joints is proposed for the dynamic analysis of periodic structures with long transfer distances. The root cause of numerical issues in the TM method arising from long transfer distances is identified. This issue is effectively addressed by discretizing the original beam segments with virtual joints. The Joint Coupling Matrix (JCM) method is used to universally describe the restraints and interactions at all joints, leading to the closed-form solutions for the dynamic responses of periodic beams. To validate the updated TM method, the natural frequencies and forced vibration responses calculated from the updated TM method are compared with those from Finite Element Method (FEM). Then, the updated TM method is used to investigate the vibration mitigation performance of periodic structures. Results from both free and forced vibration analyses reveal the variation characteristics of natural frequencies with structural periodic parameters and elucidate the relationship between the vibration mitigation performance of periodic beams and the loading frequencies. Furthermore, through Frequency Response Function (FRF) analysis, the vibration mitigation mechanism of periodic beams is examined in depth from a vibration perspective. This work provides valuable guidance for the optimal parameter configuration of periodic structures to achieve enhanced vibration mitigation performance.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120374"},"PeriodicalIF":5.6,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125224","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":"Wear theory and shear strength calculation method of cold-formed steel stud-to-oriented-strand-board fasteners","authors":"Wang Xingxing ,&nbsp;Wang Wei ,&nbsp;Zhang Yaozhao ,&nbsp;Lin Xiaodong ,&nbsp;Sun Ke","doi":"10.1016/j.engstruct.2025.120587","DOIUrl":"10.1016/j.engstruct.2025.120587","url":null,"abstract":"<div><div>The shear strength of cold-formed steel (CFS) stud-to-sheathing fasteners constitutes a critical parameter in evaluating the shear capacity of a CFS shear wall and in designing and optimizing the seismic resistance of an entire CFS structure. This study investigates the shear strength of fasteners from a new perspective of sheathing wear, targeting commonly-used oriented-strand-board (OSB), a wear theory for CFS stud-to-OSB fasteners has been developed, and a method for calculating the shear strength of these fasteners has been proposed. Furthermore, shear tests on the fasteners were conducted to verify the proposed method, and a recommendation for modifying the resistance factor of the fasteners has been suggested. The results indicate that the shear properties of the fasteners are significantly influenced by loading modes, compared with conventional cyclic loading specimens, the shear and deformation capacities of the fasteners, considering the effect of ground motion duration, are found to be significantly lower. The proposed wear theory can overcome the shortcoming of over-reliance on experiments in determining the shear strength of the fasteners, and demonstrates high accuracy in predicting their shear strength with various configurations, primarily compromised by the compression failure of the surrounding sheathing, the relative errors between the predicted and actual test results are less than 15 %. The modification method for the resistance factor of the fasteners can fully consider the significant impact of ground motion duration and can enrich the value scenarios of load fluctuation coefficient, offering guidance for designers to calculate the safety margin of CFS structures accurately.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120587"},"PeriodicalIF":5.6,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125223","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":"Testing and cross-section design of hot-rolled steel I-section beams under moment gradients","authors":"Zichang Yang ,&nbsp;Yu Chen ,&nbsp;Feng Zhou ,&nbsp;Leroy Gardner ,&nbsp;Guo-Qiang Li","doi":"10.1016/j.engstruct.2025.120610","DOIUrl":"10.1016/j.engstruct.2025.120610","url":null,"abstract":"<div><div>Moment gradients are known to enhance the cross-sectional resistance of steel beams by restricting the development of local buckling. Recently, a design approach for cross-sections under combined bending and shear that incorporates this effect has been developed, but its applicability to stiffened and unstiffened I-section beams has yet to be experimentally validated. To address this gap, a comprehensive investigation into the effect of moment gradients on the local buckling behaviour and design of I-section beams is presented. Experiments on thirteen hot-rolled steel I-section beams under four-point and three-point (with and without stiffeners) bending, covering a range of cross-sectional slendernesses and moment gradients, are described. The development of strain at critical regions within the beams was monitored during testing using a Digital Image Correlation (DIC) system. The experimental results showed that the load-carrying capacities increased with higher moment gradients for the stiffened I-section beams, while for the unstiffened beams with relatively short span lengths, the capacities slightly decreased due to the negative effect of high shear forces outweighing the beneficial effect of high moment gradients. Nonetheless, the ultimate capacities of the unstiffened three-point bending specimens still exceeded those obtained in the four-point bending tests, highlighting that the effect of moment gradients is beneficial, until high levels of shear are reached. Current design approaches are evaluated against the test results, as well as additional numerical data from previous parametric studies. A new design approach, featuring simplified flange width factors rather than the local buckling half-wavelength, is proposed to determine cross-section resistances in the presence of local moment gradients, and shown to provide accurate results. Finally, a reliability analysis is carried out following EN 1990, which confirms the reliability of the proposals within the EC3 framework.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120610"},"PeriodicalIF":5.6,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125226","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":"Size effect for dynamic flexural responses of RC beams under low-velocity impact","authors":"Pengcheng Jia,&nbsp;Hao Wu,&nbsp;Liangliang Ma","doi":"10.1016/j.engstruct.2025.120598","DOIUrl":"10.1016/j.engstruct.2025.120598","url":null,"abstract":"<div><div>The size effect is critical for the scaled impact test, which is the primary means to examine the impact resistance of full-scale reinforced concrete (RC) beams. This study investigates the size effect of RC beams under low-velocity impact and explores the similarity in dynamic flexural responses. Firstly, a simplified 3D three-phase mesoscopic finite element (meso-FE) model for concrete is proposed and verified by uniaxial compression/tensile tests on concrete specimens and drop weight tests on both reduced scale and prototypical RC beams exhibiting flexural-dominated failure modes. Then, the parametric analyses are further conducted concerning the scale factor (1−6), impact energy, and impactor mass. Findings include a 10.66 % decrease in normalized peak impact force and a 13.16 % increase in maximum mid-span deflection as the scale factor increases from 1 to 6, i.e. the significant size effect of RC beams’ dynamic responses. The aggregate size in concrete, strain rate effect, and gravity contribute to this size effect. The impact energy slightly influences while a larger mass ratio (impactor/RC beam) amplifies the size effect. Finally, a similarity relationship of the maximum mid-span deflection is established for RC beams with varying scale factors, impact energies, and impactor mass. This paper can assist to bridge the dynamic flexural responses of reduced-scale specimens and prototypical RC beams and provide practical guidance for the impact resistance design and evaluation of RC beams.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120598"},"PeriodicalIF":5.6,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125228","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":"Size effects in UHPC shear considering depth, width, and fiber alignment","authors":"Abdulrahman Salah ,&nbsp;Dimitrios Kalliontzis","doi":"10.1016/j.engstruct.2025.120544","DOIUrl":"10.1016/j.engstruct.2025.120544","url":null,"abstract":"<div><div>This research study investigated the size effects in ultra-high-performance concrete (UHPC) using the Universal Panel Tester (UPT) at the University of Houston. The experimental program included five shear panels of varying depths and widths, complemented by uniaxial tensile tests and fiber alignment analyses. Two sources of size effect were identified in the panel tests: (1) the depth size effect, recognized previously for conventional concrete, and (2) a fiber alignment effect, which varies with the formwork size in the direction of casting. Test data showed that the depth size effect is less pronounced in UHPC than conventional concrete. Existing UHPC beam shear datasets corroborated the fiber alignment effect observed in panels while showing that it can vary with the fiber dimensions.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120544"},"PeriodicalIF":5.6,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125227","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":"Dynamic behaviors of ultra-long cable with both external and internal dampers and its multi-mode damping performance optimization","authors":"Jingtao Cao ,&nbsp;Shouying Li ,&nbsp;Zhengqing Chen","doi":"10.1016/j.engstruct.2025.120601","DOIUrl":"10.1016/j.engstruct.2025.120601","url":null,"abstract":"<div><div>Ultra-long cables are susceptible to wind-induced vibrations over a wide frequency range under normal wind velocities. A dual-damper system offers a feasible solution to control multi-mode cable vibrations effectively. This study provides novel insights into the modal damping distribution of the cable-dual damper system that employs an additional high-damping rubber (HDR) internally. Dual dampers are further optimized utilizing different objective functions, one of which is newly proposed to meet varying damping requirements. The analysis begins with exploring modal behaviors of the cable-dual damper system and emphasizes high-mode damping enhancement using an additional HDR. Results show that when an external viscous damper (VD) with a small damping coefficient is used, increasing the loss factor of the HDR significantly enhances damping for modes with orders higher than the first subcritical damped mode. Moreover, modal damping of the first node mode of the cable-dual damper system mainly comes from the HDR. These phenomena depend on mode shape variations and damping contribution differences between HDR and VD. Nevertheless, this high-mode damping enhancement comes at the expense of lower-mode damping degradation due to the HDR’s stiffness. Regarding this issue, substituting the VD with the negative stiffness damper (NSD) can enhance lower-mode damping efficiently, despite damping reduction in some higher modes. On this basis, taking the NA30U cable of the Sutong Bridge as the research case, optimization designs for dual dampers are conducted using the PSO algorithm. The novel objective function can facilitate achieving a design solution that meets practical damping requirements. The HDR-VD combination performs effectively only when the VD is installed at a relatively higher position. By contrast, the HDR-NSD combination shows high effectiveness and is applicable for different positions of the NSD. Furthermore, the demand for negative stiffness consistently decreases as the NSD’s position increases. The comparative analysis with other alternative combinations shows that the optimized HDR-based dual dampers achieve a damping performance comparable to that of the double VDs.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"338 ","pages":"Article 120601"},"PeriodicalIF":5.6,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144115043","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}