Structures最新文献

{"title":"Cracking behavior of hollow ultra-high-performance concrete beams reinforced with CFRP bars","authors":"Zongze Li ,&nbsp;Haitang Zhu ,&nbsp;Lin Yang ,&nbsp;Dongdong Ji","doi":"10.1016/j.istruc.2025.108928","DOIUrl":"10.1016/j.istruc.2025.108928","url":null,"abstract":"<div><div>This study focuses on developing cost-effective ultra-high-performance concrete (UHPC) and optimizing beam cross-sectional geometries to enhance the economic viability of UHPC applications. Six hollow UHPC beams reinforced with CFRP bars (CFRP-UHPC beams) were fabricated and subjected to cyclic loading via four-point bending tests. The research investigates the effects of varying CFRP reinforcement ratios, hollow shapes (double circular and rectangular), and hollow ratios on the flexural performance of these beams. A comprehensive analysis was conducted, evaluating failure modes, crack propagation, characteristic load, deformation, and crack width. The results indicate that the newly developed UHPC containing coarse aggregates reduced costs by 43.34 % compared to conventional types and achieved scalability beyond 400 mm. A consistent failure mode was observed across all hollow beams, characterized by concrete crushing at the beam's top, initiating from the weakest point in the compression zone and progressing towards the mid-span or loading point. Reducing the cross-sectional hollow ratio significantly enhanced the flexural performance of the beams, improving cracking load, control load, ultimate load, deformation capacity, and effectively suppressing crack generation and propagation. Conversely, increasing the CFRP reinforcement ratio had the opposite effect. The influence of the hollow ratio on crack resistance was more pronounced in beams with higher hollow ratios. Rectangular hollow beams exhibited superior deformation and crack resistance compared to circular hollow beams at the same hollow ratio. A calculation model for the maximum crack width of hollow beams was developed based on composite material mechanics theory, with predicted results showing good agreement with experimental data.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108928"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828864","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}

{"title":"Finite-friction least-thickness self-standing domains of symmetric circular masonry arches. Part II: Milankovitch-like self-weight distribution","authors":"Giuseppe Cocchetti ,&nbsp;Egidio Rizzi","doi":"10.1016/j.istruc.2025.108780","DOIUrl":"10.1016/j.istruc.2025.108780","url":null,"abstract":"<div><div>The present paper constitutes a sort of compendium to a recent analysis considering the role of finite (Coulomb) friction in the mechanics of (symmetric circular) masonry arches, towards addressing least-thickness self-standing states and collapse modes possibly including sliding. Thereby, a classical Heyman-like uniform self-weight distribution along geometrical centreline was considered, and all characteristic features delivered, by a comprehensive analytical approach, corroborated by consistent outcomes from a self-made numerical Complementarity Problem/Mathematical Programming implementation. The same is now updated, for the real Milankovitch-like uniform self-weight distribution, considering the true positions of the centres of gravity of the ideal wedged-shaped chunks of the arch, with radial stereotomy. The main achieved result is that the specific conceived distribution does not alter, conceptually, the salient recorded characteristic features, in terms of types of self-standing/collapse states, though some differences are displayed, in the details of the final analytical-numerical findings, with few physical implications. However, the main implant, put to light from the previous, simpler to be mathematically handled, classical self-weight distribution, is confirmed, showing definite reference, in methodological terms, discovered features and first-order amount of technical results. In general sense, the present true Milankovitch-like self-weight distribution leads to more precise results, which support further bearing capacity for the real arch, thus anyway with conservative estimates arising from the previous approximate Heyman-like self-weight distribution, quite simpler in the underlying mechanical and mathematical treatment.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108780"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828206","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}

{"title":"Flow field characteristics and vibration response of ortho-hexagonal air-supported membrane structures","authors":"Dong Li ,&nbsp;Ziming Wang ,&nbsp;Mingxuan Lin ,&nbsp;Hongwei Huang ,&nbsp;Hongguang Xu ,&nbsp;Jie Zhao ,&nbsp;Feng Zhang","doi":"10.1016/j.istruc.2025.108893","DOIUrl":"10.1016/j.istruc.2025.108893","url":null,"abstract":"<div><div>The fluid-structure interaction (FSI) effects existing in air-supported membrane roofs subjected to wind loading are significant, which would result in the vortex-induced resonance. This study employs the particle image velocimetry (PIV) technique to systematically explore the FSI mechanism of open-typed hexagonal inflatable membrane structures, with different Reynolds numbers and angles of attack considered. The PIV system is utilized to visualize and capture the surrounding flow field characteristics, including vortex separation, turbulence intensity, and eddy structures. Simultaneously, the aeroelastic responses of the membrane structure are comprehensively analyzed in both time and frequency domains, such as the displacement statistic, vibration frequency, damping ratio, and vibration mode. By integrating the fluid spatiotemporal evolution and structural dynamics, it is indicated that the angle of attack plays a pivotal role in FSI effects. It is indicated that as the angle of attack increases, the position of vortex separation shifts from the trailing edge to the leading edge of the membrane surface. This trend would enhance the FSI effect and trigger the vortex-induced vibration (VIV). In the case of large angle of attack (20°) and Reynolds number (4.55 ×10⁵), the vortex structure develops more sufficiently, with its diameter enlarged and quantity increased significantly. The VIV phenomenon can be observed on the leeward side of the membrane when the reduced wind speed is close to 1.95, characterized by an obvious amplitude jump, a sharp reduction of damping ratios, and frequency lock-in.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108893"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828207","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}

{"title":"Behavior of SSC-filled plastic-lined steel tube (SSC-PLST) slender columns under eccentric compression","authors":"Yong Ye ,&nbsp;Qian-Song Jin ,&nbsp;De-Xian Jiang ,&nbsp;Hang Jiang ,&nbsp;Yang Liu","doi":"10.1016/j.istruc.2025.108916","DOIUrl":"10.1016/j.istruc.2025.108916","url":null,"abstract":"<div><div>This paper presents a comprehensive study on the mechanical behavior and design methodology of seawater sea sand concrete-filled plastic-lined steel tubular (SSC-PLST) slender columns under eccentric compression. A series of experiments were conducted on eighteen specimens, including twelve SSC-PLST slender columns and six hollow steel tubes, and parameters such as slenderness ratio, load eccentricity, and concrete strength were varied to observe their influence on the failure modes and load-carrying capacities of the specimens. Finite element analysis (FEA) was conducted to develop a numerical model of the SSC-PLST slender columns. Furthermore, parametric studies were conducted to evaluate the impact of concrete strength, steel strength, slenderness ratio, and load eccentricity on the ultimate load-carrying capacity of the SSC-PLST columns. The applicability of existing design method for concrete-filled steel tubular structures in calculating the ultimate load-carrying capacity of SSC-PLST slender columns was also assessed.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108916"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834623","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}

{"title":"Seismic performance of reinforced concrete double-column piers in the longitudinal direction of the bridge under the combination of compression, bending, shear, torsion","authors":"Xinggui Zeng ,&nbsp;Bao-xiong Xie ,&nbsp;Shao-Fei Jiang ,&nbsp;Peng Wang ,&nbsp;Xiaodong Lin","doi":"10.1016/j.istruc.2025.108921","DOIUrl":"10.1016/j.istruc.2025.108921","url":null,"abstract":"<div><div>To investigate the seismic performance of reinforced concrete (RC) double-column piers, particularly unequal-height double-column piers under the combination of compression, bending, shear and torsion in the longitudinal direction of the bridge, five 1:5 scale RC double-column pier specimens were designed and fabricated. The experimental parameters included the column height ratio and the applied displacement ratio by two actuators. The piers with different column height ratios were tested under the quasi-static loading with varying horizontal actuator displacement ratios in the longitudinal direction of the bridge. The results show that the increase of torsional effect by increasing the column height ratio and applied displacement ratio induced the change of failure mode of the test specimens from bending to bending-torsional failure and reduced the bending bearing capacity of double-column piers in the longitudinal direction of the bridge. With an increase in the applied displacement ratio, the torsional bearing capacity, torsional ductility, torsional stiffness, and torsional energy dissipation increased, while the bending bearing capacity and bending ductility and bending stiffness decreased. However, the bending energy dissipation did not decreased significantly (almost unchanged). Additionally, with an increase in the column height ratio, the bending bearing capacity, bending stiffness, and bending energy increased, while the torsional bearing capacity, bending and torsional ductility, torsional stiffness, and the torsional energy decreased, particularly when the column height ratio was greater than 4:3.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108921"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834621","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}

{"title":"Topological form-finding analysis of regular tensegrity structure based on parallel component coding algorithm","authors":"Wanpeng Zhang ,&nbsp;Xiaodong Feng ,&nbsp;Xian Xu ,&nbsp;Yuhan Lin ,&nbsp;Li Zheng ,&nbsp;Yu Chen","doi":"10.1016/j.istruc.2025.108906","DOIUrl":"10.1016/j.istruc.2025.108906","url":null,"abstract":"<div><div>To address the problem of form-finding in complex symmetric tensegrity structures, a topology form-finding algorithm based on a parallel component coding strategy (PCC) is proposed. Initially, parallel components are categorized into groups based on the base structure model. By integrating tensegrity structure morphological analysis theory, the spatial morphology of the structure is established through the splicing and recombining of components from different groups while accounting for constraints such as element collision, geometric stability, and the zero-bar phenomenon. Subsequently, metrics, including the symmetry index, pressure bars count ratio, and internal force uniformity, are employed to evaluate and analyze various structural topological forms. Using 12-node and 18-node spatial tensegrity structures as examples, a tensegrity structure with high topological symmetry is effectively obtained and screened according to different group numbers, thereby fully verifying the feasibility and accuracy of the algorithm. The Random Forest Classification (RF) model was introduced to form the PCC-RF algorithm. By comparing the computational efficiency of PCC and PCC-RF in the form-finding process of tensegrity structures, the results indicate that PCC-RF significantly reduces computational time and provides a new efficient approach for exploring complex and highly symmetric tensegrity structures.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108906"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834628","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}

{"title":"An integrated analysis procedure for evaluating the nonlinear peak response of inter-story isolated structure employing an adaptive variable friction pendulum","authors":"Kui Yang ,&nbsp;Ping Tan ,&nbsp;Huating Chen ,&nbsp;Jiying Shang ,&nbsp;Yue Xiang ,&nbsp;Yafeng Li","doi":"10.1016/j.istruc.2025.108874","DOIUrl":"10.1016/j.istruc.2025.108874","url":null,"abstract":"<div><div>Inter-story isolated structures with conventional friction pendulum isolators (FPIs) are not widely utilized because of their poor limiting ability and the absence of matching response spectrum analysis procedures. This study proposes an integrated analytical procedure (IAP) that effectively considers the structural characteristics and accurately evaluates the maximum response of a structure, eliminating the necessity of nonlinear response history analysis (NRHA). The procedure initially establishes a simple and practical mechanical model based on the characteristics of an adaptive variable friction pendulum isolator (AVFPI), in which the friction coefficient velocity dependency is obtained by fitting test data using a novel material, and the simplified theoretical mechanical model is evaluated via the same full-scale isolator test. In the context of stochastic vibration theory, the equivalent parameter of the isolation layer is determined by expressing it as the expected displacement amplitude. This expression was derived by employing the energy-balance approach in the state of maximum isolator displacement. Although the equivalent parameters depend on the mean square value of the peak displacement response, this study employs the peak coefficients of the statistical response on basis of the stochastic vibration theory without using the power spectrum as a solution technique. To achieve this, an iterative calculation procedure is designed by integrating the design response spectrum and the combination rule of the complex-mode-superposition complete square combination (CCQC). This process was used to construct the complete IAP framework. The accuracy of the approach was evaluated through a statistical analysis of a set of adaptive variable friction pendulum inter-story isolated structures (AVF-IISs), and its effectiveness was further confirmed through actual examples. The study revealed that the proposed mechanical model can effectively respond to the hysteretic behavior of the AVFPI. The developed IAP can achieve the desired range of prediction error for the displacement of an AVF-IIS, and the structural shear force prediction accuracy is acceptable.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108874"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828868","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}

{"title":"Post-fire performance of welded beam-to-column joint under monotonic and cyclic loading","authors":"Fan-Qin Meng ,&nbsp;Mei-Chun Zhu","doi":"10.1016/j.istruc.2025.108926","DOIUrl":"10.1016/j.istruc.2025.108926","url":null,"abstract":"<div><div>The study on the post-fire performance of welded beam-to-column steel joints is crucial for assessing the residual capacity of steel structures and providing structural reinstatement following a fire accident. Therefore, this study experimentally examined the post-fire behaviour of welded beam-column joints subjected to monotonic and cyclic loading conditions. In this research, ten welded beam-to-column joints were subjected to monotonic and cyclic loading protocols until failure after being exposed to temperatures at 20 ℃, 500 ℃, 600 ℃, 700 ℃, and 800 ℃. For specimens subjected to monotonic loading, the experimental results showed that the failure mode of the connection specimens shifted from beam flange buckling to butt weld cracking as the exposure temperature increased to 500°C and above, and the bending moment capacity of the joint generated the maximum 20 % decline. For specimens subjected to cyclic loading, although the strength of the welded beam-to-column joint declined 20 % after high-temperature exposure, the specimen still showed a plumper hysteretic loop, indicating a good energy dissipation performance. The most notable changes were observed at the exposure temperature of 700°C, where the ductility coefficient increased by 14 % and the energy dissipation coefficient rose by 19 %.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108926"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828869","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}

{"title":"Synergistic potential of topology optimization and lattice structures in concrete 3D printed beams","authors":"M.P. Salaimanimagudam,&nbsp;J. Jayaprakash","doi":"10.1016/j.istruc.2025.108892","DOIUrl":"10.1016/j.istruc.2025.108892","url":null,"abstract":"<div><div>This paper presents the integration of topology optimization and lattice structures in 3D-printed concrete beams to enhance structural performance and efficiency. Various beam designs, including solid, hexagon lattice, reentrant lattice, square lattice, and topology-optimized + Lattice hybrid configurations, are printed using the concrete 3D printing technique. The 3D-printed beams are tested under two-point loading to determine the load-bearing capacity, material efficiencies, and manufacturability. Results show that the topology-optimized square lattice beam achieved approximately 99.7 % of the solid beam's capacity with a 23 % reduction in material usage, while the topology-optimized reentrant lattice beam reached 95.9 % of the solid beam's capacity with an 81.1 % volume fraction. These findings demonstrate the superior performance of topology-optimized + Lattice hybrid designs in terms of load-bearing capacity and material efficiency compared to traditional solid and lattice beams. From the experimental investigation, it was also noted that no premature failure due to inter-layer delamination was observed during the testing phase.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108892"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834622","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}

{"title":"Intelligent optimization method for seismic risk transfer parameters of high-speed railway track-bridge system","authors":"Wangbao Zhou ,&nbsp;Yingjie Li ,&nbsp;Lijun Xiong ,&nbsp;Lizhong Jiang ,&nbsp;Zhaozhao Ma","doi":"10.1016/j.istruc.2025.108912","DOIUrl":"10.1016/j.istruc.2025.108912","url":null,"abstract":"<div><div>Due to the widespread use of high-speed railway simply supported beam bridges in areas prone to high-risk earthquakes, the challenge of risk control for these bridges under seismic activity has become increasingly significant. Therefore, this study develops a finite element model to analyze the seismic response characteristics of the high-speed railway track-bridge system. It proposes a seismic risk transfer system for the high-speed railway track-bridge system. Then, an adaptive hybrid optimization algorithm is constructed, combining Particle Swarm Optimization (PSO) and Simulated Annealing (SA). This algorithm is used to create a neural network-based intelligent optimization method for configuring the parameters of the risk transfer device. In addition, the efficiency of the optimized risk transfer device is evaluated under various earthquake scenarios. The results indicated that the optimized seismic risk transfer device significantly enhances the seismic performance of the high-speed railway track-bridge system. The intelligent optimization method for the seismic risk transfer device parameters substantially reduces the stiffness requirements of the device, yielding economic benefits. The risk transfer device successfully mitigates the seismic risk to the bridge by transferring it to a more easily repairable embankment structure, thus reducing post-earthquake maintenance time and costs. These research results provide novel insights into the seismic design and optimization of bridges.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"76 ","pages":"Article 108912"},"PeriodicalIF":3.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828205","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}