Engineering Structures最新文献

{"title":"A novel multi-task graph neural network model for cable force optimization in cable-stayed bridges","authors":"Yuhang Lei ,&nbsp;Qunfeng Liu ,&nbsp;Xing Wu ,&nbsp;Shimin Zhu ,&nbsp;Jun Zhao ,&nbsp;Xiang Ren","doi":"10.1016/j.engstruct.2025.121468","DOIUrl":"10.1016/j.engstruct.2025.121468","url":null,"abstract":"<div><div>This study proposes a novel multi-task graph neural network (MT-GNN) surrogate model for efficient, multi-objective cable force optimization in cable-stayed bridges. The MT-GNN is trained on heterogeneous graph data derived from finite element simulations conducted over a Latin Hypercube Sampled design space, leveraging a Huber loss function with uncertainty weighting to concurrently predict node displacements and element bending moments. Integrating this trained MT-GNN into the NSGA-II framework enables rapid optimization aimed at simultaneously minimizing total girder vertical displacements and total bridge bending moment energy. Case studies on two-dimensional (2D) and three-dimensional (3D) single-pylon cable-stayed bridges demonstrate that the proposed framework achieves prediction accuracies comparable to finite element (FE) analysis, while drastically reducing computational costs. The optimized designs exhibit superior structural performance over traditional strategies, particularly for complex 3D configurations. These results demonstrate that the MT-GNN-based framework offers a computationally efficient, robust, and practical tool for multi-objective cable force optimization in cable-stayed bridges.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121468"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218614","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":"Seismic performance of RC columns retrofitted using thick-hybrid-wall technique","authors":"Mohammad Zahid Noori ,&nbsp;Kozo Nakada ,&nbsp;Kazuo Kaneda ,&nbsp;Masayuki Kuroki ,&nbsp;Kazuto Fujishita ,&nbsp;Masayuki Tokura","doi":"10.1016/j.engstruct.2025.121448","DOIUrl":"10.1016/j.engstruct.2025.121448","url":null,"abstract":"<div><div>This study examined the seismic performance of reinforced-concrete (RC) columns retrofitted using the thick-hybrid-wall (THW) technique with carbon fiber–reinforced panels (CFRPs). THW is a strength–ductility-type seismic retrofit technique developed to strengthen piloti-type RC buildings by incorporating additional concrete walls, steel plates, and high-strength bars called PC bars. Herein, six retrofitted specimens were tested under axial and lateral loads to evaluate their ultimate shear and flexural strengths, failure modes, and the experimental performance of the CFRPs. In this study, the CFRPs were used instead of the steel plates. Compared with steel plates, CFRPs offer advantages such as durability, light weight, high tensile strength, and construction simplicity. The additional wall length, bond performance of the rebars, presence/absence of PC bars, lateral confinement pressure, and axial force were the research variables. A theoretical equation for obtaining the demand flexural strength was developed, and the shear strength equation was modified, which resulted in an accuracy of &gt; 95 %. Moreover, a model was developed to assess the interaction of the axial force with the shear and flexural strengths, which enabled the simultaneous evaluation of the shear and flexural strengths and prediction of the failure modes of the retrofitted columns. The test results indicate that the CFRP improves the lateral strength and ductility of the retrofitted columns; however, it does not exert a confinement effect on the compressive strength of concrete. The effects of the research variables on the seismic performance of the retrofitted columns were examined and the accuracy of the analytical models was validated experimentally.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121448"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218617","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":"Experimental study on seismic performance of infilled frames with improved flexible connection","authors":"Lihong Xiong ,&nbsp;Zhuoxin Wang","doi":"10.1016/j.engstruct.2025.121467","DOIUrl":"10.1016/j.engstruct.2025.121467","url":null,"abstract":"<div><div>This study examines the seismic performance of infilled frames with improved flexible connections (IFC), addressing limitations of conventional flexible connections (FC) recommended by Chinese seismic design codes. In-plane (IP) and out-of-plane (OOP) quasi-static tests were conducted on both IFC and FC infilled frames to evaluate and compare their bi-directional seismic behavior. Additional OOP tests on IFC infills were performed to establish performance levels. Finite element simulations were developed to reproduce the IP and OOP responses, and were validated against experimental hysteresis behaviors and damage patterns to explore underlying damage mechanisms further. Results demonstrate that IFC infills utilizing basalt fiber grid (BFG) tie-belts provide superior in-plane decoupling and out-of-plane stability compared to FC infills, especially for autoclaved aerated concrete (AAC) masonry. Under bi-directional loading, FC infills exhibited reduced OOP capacity due to prior in-plane damage, revealing potential vulnerabilities of conventional steel reinforcement connections. The proposed IFC system effectively mitigates these vulnerabilities and achieves enhanced IP capacity objectives and OOP performance, offering a robust solution for improving the seismic resilience of infilled frame structures.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121467"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218550","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":"Experimental investigation on fatigue vulnerability of integral joints in double-deck steel truss girders under out-of-plane loads","authors":"Yi Shi ,&nbsp;Yingwen Zhang ,&nbsp;Lei Jiang ,&nbsp;Yongjian Liu ,&nbsp;Li Liang ,&nbsp;Zhenbei Liu ,&nbsp;Yinping Ma ,&nbsp;Jian Li","doi":"10.1016/j.engstruct.2025.121450","DOIUrl":"10.1016/j.engstruct.2025.121450","url":null,"abstract":"<div><div>To investigate the fatigue behavior of integral joints in double-deck steel truss girders under out-of-plane loads, this study took the Shiziyang Bridge as a case study and conducted full-scale model tests on the upper and lower integral joints. The nominal stresses, hot spot stresses, and stress concentration factors (SCF) at member connections under out-of-plane loading were measured and analyzed. A numerical analysis of the SCF at the connection between the crossbeam top plate and the gusset plate was conducted using response surface methodology (RSM). A set of parametric formulas was developed to calculate the SCF for this structural detail. Based on the analysis results, the fatigue performance of the Shiziyang Bridge main truss joints was evaluated. The results indicated that under out-of-plane loading, the stress concentration effects at the connections between the crossbeam flanges (top and bottom) and the gusset plate were significantly greater than those at the connections between the chord and the gusset plate. Moreover, the lower joints exhibited a substantially higher stress concentration effect than the upper joints. Under the experimental loading conditions, the maximum SCF at the connection between the crossbeam and the gusset plate reached 2.37 and 4.67 for the upper and lower joints, respectively. The crossbeam top plate thickness, crossbeam web thickness, gusset plate thickness, and weld hole diameter all significantly influenced the SCF at the connection, and the proposed parametric formulas provided a good fit. Under fatigue load model II, considering the out-of-plane loading on the joints, the most critical detail in the main truss joints of the Shiziyang Bridge was the connection between the crossbeam top plate and the gusset plate, where the maximum hot spot stress range reached 41.31 MPa. When the hot spot stress S–N curve corresponding to fatigue detail category 90 MPa was applied to the fully welded integral joints, the fatigue performance of the main truss joints met the relevant code requirements.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121450"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218556","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":"Seismic evaluation of Gas Insulated Lines (GIL) based on a newly defined key control metric and a simplified theoretical model","authors":"Xiaoxuan. Li ,&nbsp;Qiang. Xie ,&nbsp;Shenggang Fan ,&nbsp;Jiayi Wen","doi":"10.1016/j.engstruct.2025.121466","DOIUrl":"10.1016/j.engstruct.2025.121466","url":null,"abstract":"<div><div>With the increasing deployment of Gas Insulated Lines (GIL) in ultra-high voltage (UHV) substations located in high seismic intensity areas, there is an urgent need to assess its seismic performance. However, the unique coaxial structure and internal electrical connections of GIL prevent the direct application of conventional seismic performance indicators to effectively characterize its potential failure modes. This study first identifies two primary failure modes of GIL—outer shell strength failure and inner conductor pull-out failure—through nonlinear time-history analysis, concentrated at the corner junctions of high-height-difference vertical sections. Based on these findings, the Inter-segment Drift Ratio (IDR) is proposed as a key control parameter for quantitatively evaluating the seismic performance of GIL. A simplified theoretical model is then developed to investigate the influence of support stiffness configuration on GIL’s seismic performance through parametric analysis. The results demonstrate that the simplified theoretical model, based on IDR, provides high accuracy, with a deviation of only ±5 % compared to finite element analysis results, making it more suitable for practical engineering design with minimal computational cost. Furthermore, adjusting the support stiffness on both sides of the height-difference section can significantly improve the overall seismic performance of GIL. In conclusion, this study introduces an innovative approach for evaluating the seismic performance of GIL, offering a practical framework for enhancing its resilience in seismic-prone UHV substations.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121466"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218610","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 behavior of steel fiber-reinforced geopolymer lightweight aggregate concrete beams","authors":"Xi Liu,&nbsp;Zhen-jun Li,&nbsp;Ming-xing Jiang,&nbsp;Hui Wang,&nbsp;Tian-hao Wu","doi":"10.1016/j.engstruct.2025.121442","DOIUrl":"10.1016/j.engstruct.2025.121442","url":null,"abstract":"<div><div>Eight hooked-end steel fiber-reinforced geopolymer lightweight aggregate concrete (SFGLAC) beams were tested to investigate failure modes, cracking behavior, and moment-deflection response. The fractal theory was employed to quantitatively analyze the variation in crack patterns and propagation behavior, thereby establishing the relationship between crack fractal dimension and flexural properties. To further capture the nonlinear stress–strain behavior of concrete, a novel dynamic gradient-optimized layered (DGOL) method was developed, enabling detailed cross-sectional stress analysis. Experimental results demonstrated that SFGLAC beams exhibited favorable crack distribution, characterized by narrow and densely spaced cracks that formed interconnected networks with multiple branching patterns. Quantitative fractal analysis demonstrated that the surface crack patterns exhibited distinct fractal characteristics, with the crack fractal dimension showing strong statistical correlations with both residual flexural capacity and flexural stiffness degradation. Additionally, Comparative assessments with existing design standards further indicated that both Chinese and American codes provide conservative predictions of the ultimate moment capacity of hooked-end fiber-reinforced GLAC beams. The proposed DGOL-based ultimate moment model demonstrated superior predictive accuracy with minimal dispersion, as evidenced by a coefficient of variation below 2 %.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121442"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218440","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":"Axial stress distributions in FRP-confined concrete columns: Pressure-film measurements and finite element predictions","authors":"Jun-Jie Zeng ,&nbsp;Bo-Tong Zheng ,&nbsp;Jin-Guang Teng ,&nbsp;Jian-Fei Chen","doi":"10.1016/j.engstruct.2025.121419","DOIUrl":"10.1016/j.engstruct.2025.121419","url":null,"abstract":"<div><div>Understanding the stress distribution in fiber-reinforced polymer (FRP)-confined concrete sections remains challenging primarily because no effective technique for direct stress measurement has been developed. This knowledge deficiency may lead to serious errors in current design standards for buildings and infrastructures. In this study, we developed a novel approach for directly measuring axial stress distributions in FRP-confined concrete columns by using digital pressure-sensing films. Measured stress distributions based on the proposed approach after Gaussian smoothing are compared with finite element (FE) results obtained with the evolutionary potential-surface trace (EPT) model at selected load levels. These comparisons showed a reasonably close alignment in terms of overall trend between the smoothed pressure-film data and the FE predictions with localized discrepancies. The differences between the test results and the FE predictions are the largest in the corner regions of square columns (with the maximum difference being 56 %) and at the long-side midpoints of rectangular columns (with the maximum difference being 42 %), although the differences at other locations are generally below 20 %. These findings not only demonstrate the capability of pressure films in measuring stress distributions in concrete columns, but also validate the EPT constitutive model. The combined use of pressure films and FE modeling offers significant potential for understanding and modeling internal stress distributions in structural elements.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121419"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218547","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":"Shear strengthening of rectangular and T-shaped reinforced concrete beams with iron-based shape memory alloy (FeSMA) strips","authors":"Huanpeng Hong ,&nbsp;Abdeldjelil Belarbi ,&nbsp;Bora Gencturk ,&nbsp;Lara Zerbe","doi":"10.1016/j.engstruct.2025.121423","DOIUrl":"10.1016/j.engstruct.2025.121423","url":null,"abstract":"<div><div>In this paper, a comprehensive experimental investigation was performed to understand the behavior of shear critical beams strengthened with iron-based shape memory alloy (FeSMA) prestressing. The influence of the FeSMA activation process on the prestressing behavior of the material was investigated, a comparison between rectangular and T-beams shear strengthened with FeSMA was made, and the combined effects of the transverse reinforcement configuration (including both internal stirrups and external FeSMA strips) and the anchoring method was studied. First, the elastic modulus, yield stress, fracture stress of passive FeSMA and the recovery strain and recovery stress of active FeSMA was determined. The effects of heating approach, prestrain level, activation temperature, and the portion of the FeSMA length that is activated on the recovery stress of FeSMA were studied. Second, twenty shear critical RC beams were tested, including eight rectangular and twelve T-beams. The following variables were investigated in these beam tests; namely, the stirrup spacing, FeSMA spacing, number of FeSMA layers, use of passive or active FeSMA, and the method used in installation of FeSMA. For all beams, the crack patterns, failure modes, shear force-deflection responses, and strains in the stirrups and FeSMA were analyzed. The results demonstrated that for both rectangular and T-beams, the failure modes of beams strengthened with FeSMA strips shifted from shear to flexure; further, the beams strengthened with active FeSMA strips exhibited fewer and narrower cracks than beams strengthened with passive FeSMA strips. Compared with the control specimen, both the peak shear force and the deflection at peak force of rectangular and T-beams increased after strengthening with FeSMA strips.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121423"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218553","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":"Life-cycle environmental impact optimization of an RC-THVS composite frame for sustainable construction","authors":"Iván Negrin ,&nbsp;Moacir Kripka ,&nbsp;Víctor Yepes","doi":"10.1016/j.engstruct.2025.121461","DOIUrl":"10.1016/j.engstruct.2025.121461","url":null,"abstract":"<div><div>This study investigates the benefits of Life-Cycle Environmental Impact Optimization (LCEIO) in structural engineering, focusing on the RC-THVS composite typology as a sustainable alternative for frame-building construction. This innovative structural system integrates reinforced concrete (RC) columns with Transversely Hybrid Variable Section (THVS) steel girders serving as beam elements. The optimization problem is formulated to optimize the Global Warming Potential of the building structure during its life cycle. A novel LHS-CINS algorithm is introduced to solve the formulated optimization problems efficiently. Results show that LCEIO reduces environmental impact significantly, with optimized structures achieving up to a 32 % reduction in emissions compared to traditionally designed buildings. The most substantial improvement occurs in the manufacturing phase, where THVS girders lower emissions by up to 70 % compared to traditional I-section profiles. Additionally, maintenance-related impacts decrease by 45 % due to the girders' optimized tapered geometry. When comparing optimized solutions, rigid-joint composite typologies outperform RC systems in low-aggressiveness environments, reducing life-cycle emissions by 30 %. In highly aggressive environments, composite structures remain more sustainable than RC ones, although maintenance impacts are accentuated. Beyond individual component performance, THVS girders contribute to overall structural efficiency by reducing self-weight, thereby lowering axial loads on columns and foundations. Moreover, when slabs and walls are integrated into the superstructure, composite typologies further enhance system efficiency, cutting emissions by up to 42 % compared to bare frame models. The findings emphasize the capability of LCEIO and composite configurations to design more sustainable, efficient, and environmentally responsible building solutions.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121461"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218609","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":"Blast performance and damage assessment of square reinforced concrete (RC) panels with openings","authors":"Chaofeng Hua ,&nbsp;Hong Hao ,&nbsp;Yifei Hao","doi":"10.1016/j.engstruct.2025.121476","DOIUrl":"10.1016/j.engstruct.2025.121476","url":null,"abstract":"<div><div>Reinforced concrete (RC) panels are frequently designed with door and window openings to fulfill functionality requirements such as lighting, ventilation, and access. Understanding the blast resistance of these panels with openings is critical for ensuring structural safety under blast loading conditions. This study delves into the blast response of three RC panels (2.2 m × 2.2 m ×0.13 m) through field tests using 9 kg of TNT at a scaled distance of 0.61 m/kg^1/3. The tested panels include one with a window opening, one with a door opening, and one solid panel as a reference. The experimental results noted that while all panels exhibited flexural damage, the panels with openings demonstrated a better blast resistance, owing to the opening that effectively reduced blast loads acting on the panel. At the same measurement location, the door-opening panel exhibited a 19.5 % reduction in maximum displacement and a 69.6 % reduction in residual displacement compared to the solid panel. Subsequently, finite element models were developed using LS-DYNA and verified against the experimental results. The numerical analysis highlighted that the openings altered the distributions of internal forces. A series of numerical simulations were performed to develop pressure-impulse (P-I) diagrams for panels with and without openings, basing on the UFC damage criteria. The results indicated that panels with openings exhibited less damage than solid panels. Analytical formula with best fitted parameters for constructing the P-I diagrams of the studied panels was developed for quick assessment of the panel performance under blast loadings for practical applications.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121476"},"PeriodicalIF":6.4,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218506","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}