Engineering Structures最新文献

{"title":"Effects of cutouts on the axial buckling strength of steel thin-walled cylindrical shells","authors":"Kamyab Rezaee,&nbsp;Alireza Moazezi Mehretehran","doi":"10.1016/j.engstruct.2025.120149","DOIUrl":"10.1016/j.engstruct.2025.120149","url":null,"abstract":"<div><div>Steel cylindrical shells are among common configuration in many industrial structures. For access reasons, cutouts are used in these structures, which can aggravate the buckling susceptibility. Among the different length categories defined in EN 1993–1–6, the medium-length cylindrical shells are prevalent structures. There is little information on the effect of different cutout sizes and boundary conditions on the buckling strength of such structures. Accordingly, this paper presents a numerical finite element (FE) investigation to assess the load-bearing capacity of medium-length shells with cutouts, under axial compressive loads. Some equations are proposed to quantify the results obtained from the verified FE models. In order to examine the applicability of the proposed equations, a set of steel silos was selected as the case study. The results obtained demonstrated that the equations are able to make acceptable predictions. As a complementary study, the effect of adding ring stiffeners around the cutout and including initial imperfections was also assessed.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120149"},"PeriodicalIF":5.6,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685098","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 features and control of wind-induced instability of parallel dual main cables of ultra-long-span suspension bridge in construction phases","authors":"Yangchen Deng ,&nbsp;Linyu Li ,&nbsp;Shouying Li ,&nbsp;Weicheng Hu","doi":"10.1016/j.engstruct.2025.120141","DOIUrl":"10.1016/j.engstruct.2025.120141","url":null,"abstract":"<div><div>During the construction phase of single-sided parallel double main cables without the constraint of hangers, the low frequency of the main cables and the continuous variation in their cross-sectional shape make them highly susceptible to harmful wind-induced vibrations under commonly encountered wind speeds. In this study, the features of wind-induced vibration of parallel dual main cables in construction phases and the effectiveness of different countermeasures were studied by using wind tunnel tests. Firstly, based on the design scheme of single-side parallel dual main cables for a large-span suspension bridge with a main span of 2180 m, five segmental models of typical cross-sectional shapes of dual main cables during the construction phase were manufactured. Subsequently, a series of vibration measurement wind tunnel tests were carried out to obtain the wind-induced responses of the dual main cables under typical construction cases. Then, the aerodynamic damping of representative vibration cases was identified to explore the instability mechanism. The results indicate that wind-induced vibrations of dual main cables during the construction phase primarily manifest in three forms: vibration of the upstream main cable only, vibration of the downstream main cable only, and simultaneous vibration of both upstream and downstream main cables. The aerodynamic damping characteristics vary significantly among these different vibration modes. Finally, the effectiveness of four countermeasures was experimentally studied, including adjusting the spacing between the dual main cables and the construction progress, wrapping the cables with temporary plastic film and increasing structural damping. The results indicate that, compared to the other three countermeasures, the asynchronous construction of the two main cables demonstrates the greatest potential in mitigating wind-induced instability.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120141"},"PeriodicalIF":5.6,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685547","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":"Long-term performance of recycled aggregate concrete beams exposed to 10 years of loading and chloride environments","authors":"Bingcheng Chen,&nbsp;Yuxi Zhao,&nbsp;Ligang Peng","doi":"10.1016/j.engstruct.2025.120140","DOIUrl":"10.1016/j.engstruct.2025.120140","url":null,"abstract":"<div><div>To address concerns over the long-term durability of reinforced concrete beams incorporating recycled coarse aggregate (RCA), this study investigates beams with RCA replacement rates of 0 %, 50 %, and 100 % under ten years of sustained loading and chloride exposure. A comprehensive evaluation was conducted to examine the effects of RCA replacement on cracking patterns, carbonation depth, chloride ingress, reinforcement corrosion, and residual flexural capacity. The results show that higher RCA replacement rates significantly increase both transverse and longitudinal cracking on the beam surfaces, caused by the combined effects of localized stresses from sustained loading and chloride-induced reinforcement corrosion. As RCA replacement increases, both carbonation depth and chloride concentration rise, with notable differences between tension and compression zones. These interactions between RCA material properties and environmental exposure accelerate corrosion in both longitudinal and stirrup reinforcement, particularly in tensile regions. Although RCA replacement rates did not notably alter the failure modes, at damage ages of 120 months, higher RCA replacement correlated with increased deflection and a significant reduction in residual flexural capacity, with a 1.27 % reduction for RAC50 and a 12.94 % reduction for RAC100 at 120 months. To better predict the flexural strength of corroded concrete beams, this study introduces a time-dependent flexural capacity reduction coefficient (<em>β</em>_<em>r</em>), incorporating RCA replacement rate (<em>r</em>) and loading time (<em>t</em>). This research underscores the critical need to consider RCA replacement rates and long-term environmental exposure when designing concrete beams to optimize durability in aggressive environments.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120140"},"PeriodicalIF":5.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654795","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":"Probabilistic seismic performance assessment of base-isolated buildings incorporating SMA gap dampers for pounding mitigation","authors":"Tianhao Yu ,&nbsp;Bin Wang ,&nbsp;Peng Chen ,&nbsp;Theodore L. Karavasilis","doi":"10.1016/j.engstruct.2025.120111","DOIUrl":"10.1016/j.engstruct.2025.120111","url":null,"abstract":"<div><div>Moat wall (MW) pounding is prone to occurring in seismically base-isolated buildings equipped with insufficient isolation clearances due to architectural constraints, particularly during strong near-field earthquake excitations. When MW pounding occurs, the earthquake responses of the isolation layer and superstructure are significantly amplified. Hence, various hysteretic gap dampers (GDs) have been developed to exhibit additional stiffness and damping for pounding mitigation during strong earthquakes, while maintaining the isolation system’s performance during small-to-moderate earthquakes. However, the effectiveness of GDs may be compromised during immediate aftershocks or future earthquakes because of their limited self-centering (SC) capabilities. For this reason, this study develops SC GDs in an adaptive isolation system, aiming to achieve optimal response control in the isolation layer and superstructure during multiple strong earthquakes through incorporating shape memory alloy (SMA) and steel GDs. Different isolation systems were designed with various GDs, i.e., SMA-, steel-, and combined-GDs, to achieve the same maximum bearing deformation under maximum considered earthquakes for comparative investigations. Seismic fragility analyses are conducted to investigate the influence of GDs’ mechanical behavior on isolation effectiveness, considering mainshock–aftershock sequences. Fragility analysis results show that the designed GDs significantly reduce the probability of bearing damage compared to conventional MWs. The mechanical behavior of GDs remarkably affects the isolation performance of the adaptive isolation systems. Specifically, unlike the steel-GDs experienced unrecoverable cumulative damage, the SMA-GDs with excellent SC capability exhibit superior deformation mitigation, especially under aftershock conditions, while sacrificing higher exceedance probabilities of superstructural drifts, which is due to the inherent lower energy dissipation capability. The combined-GDs demonstrate optimal response control between the isolation layer and the superstructure.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120111"},"PeriodicalIF":5.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654798","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":"Nonlinear repairing analysis of damaged transmission tower under different seasonal loads and support movement: Assessment of repair measures and strength recovery","authors":"Yuto Yamano ,&nbsp;Kumpei Tsuji ,&nbsp;Hiroki Mizoe ,&nbsp;Tasuku Muroi ,&nbsp;Yuki Yamakawa","doi":"10.1016/j.engstruct.2025.120029","DOIUrl":"10.1016/j.engstruct.2025.120029","url":null,"abstract":"<div><div>Member damage and collapse of transmission towers are caused by excessive loads due to strong winds and ice/snow accretion, as well as support movement due to ground deformation. The characteristics of such excessive loads vary significantly depending on the season. In this study, we examined the progress of member damages and the degradation of ultimate strength of a transmission tower subjected to different seasonal loads and support movement using 3D nonlinear finite element analysis. A series of damage analyses revealed that the distribution of member damages varies depending on the causes and degrees of damage. We also evaluated quantitatively the degradation of ultimate strength after damages. Further, we attempted a repair simulation by replacing damaged members or removing support movement to assess the strength recovery after repair. The analysis results implied that choosing the appropriate repair method and releasing compressive residual stress in members are essential for effective strength recovery.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120029"},"PeriodicalIF":5.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654799","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":"Compressive behavior of partially prefabricated concrete-encased-and-filled steel tubular columns","authors":"Yun-Peng Ji ,&nbsp;Hong-Song Hu ,&nbsp;Biao Peng ,&nbsp;Konstantinos Skalomenos","doi":"10.1016/j.engstruct.2025.120129","DOIUrl":"10.1016/j.engstruct.2025.120129","url":null,"abstract":"<div><div>This paper develops a novel concrete-encased-and-filled steel tubular (CEFST) column that employs a concrete-filled steel tube encased into a high ductility concrete (HDC). The steel tube and the HDC are prefabricated parts of the column while concrete infill is cast on-site. To investigate the axial compressive behavior of the novel prefabricated column, an experimental campaign was carried out involving twelve prefabricated CEFST columns, five conventional concrete-filled steel tubular (CFST) columns, and three typical reinforced concrete (RC) columns. The test variables included the width-to-thickness ratio of the steel tube, the number of tie bars arranged in rows along the height of the column to restrain the evolution of tube local buckling, the tensile strength of the tie bars, and the shape of the tie bar nuts used to enhance the mechanical connection between the materials, i.e., the inner steel tube and the HDC. Overall, prefabricated CEFST columns of the same steel content ratio and material strengths as the corresponding RC columns exhibited higher ductility. Test results indicated that tie bars in CEFSTs can effectively restrain the outward buckling of the steel tube by limiting the formation of local buckling within their pitch distance. By increasing the number of tie bars or using ring-type nuts instead of conventional nuts, the onset of local buckling can be delayed, hence the initiation of column's strength degradation. It was also found that by arranging the tie bars in more than two rows within the critical height of the column, the tensile strength of the high-strength tie bars can be fully utilized resulting in an improved post-peak strength of CEFSTs. Based on test results, a fairly accurate design formula was proposed for calculating the compression strength of CEFST columns.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120129"},"PeriodicalIF":5.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654831","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 the seismic performance of T-shaped connected modular beam-column connection","authors":"Jixiang Xu,&nbsp;Jizong Liang,&nbsp;Jianping Han,&nbsp;Yifan Zhang","doi":"10.1016/j.engstruct.2025.120108","DOIUrl":"10.1016/j.engstruct.2025.120108","url":null,"abstract":"<div><div>This paper introduces T-shaped connected modular beam-column (TMBC) connection that incorporates a Replaceable Panel Zone Column (RPZC). This semi-rigid connection design enables localized reinforcement at a reduced cost, significantly enhancing the overall seismic resistance capability of the TMBC connection. To this end, three types of TMBC connection specimens were designed and manufactured: the RPZC flange plate reinforced specimen (SPC-1), the RPZC web plate reinforced specimen (SPC-2), and the T-shaped connector reinforced specimen (SPC-3). All three specimens were subsequently tested under pseudo-static conditions. This study comprehensively evaluates the seismic performance and failure characteristics of TMBC connections in accordance with an in-depth analysis of the entire process of elastic-plastic deformation. Additionally, a comparative analysis is conducted, focusing on hysteretic curves, skeleton curves, equivalent viscous damping coefficients, and stiffness degradation patterns. Moreover, theoretical derivations have confirmed that the deformation at the flange connection is negligible. The experimental results indicate that the load-bearing capacity of SPC-1 is 5.2 % higher than that of SPC-2 and 11–13.5 % higher than that of SPC-3, while the load-bearing capacity of SPC-2 is approximately 8 % higher than that of SPC-3. At a horizontal displacement of 56.2 mm, the energy dissipated by SPC-3 is about 19 % and 22 % less than that of SPC-1 and SPC-2, respectively. Furthermore, reinforcing the flange and web in the RPZC region proves more effective than reinforcing only the flange plate on the T-connector, demonstrating that this reinforcement method can effectively transfer the plastic hinge to the T-connector. In conclusion, the modular design not only enhances the assembly efficiency of TMBC connections but also achieves semi-rigid behavior at the joints through the T-connector. Additionally, the design of RPZC and the T-connector addresses the issue of insufficient replaceability in the connections.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120108"},"PeriodicalIF":5.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685545","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":"Anchorage of reinforcement in concrete corners: Experiments and refined measurements","authors":"Xianlin Wang ,&nbsp;Enrique Corres ,&nbsp;Aurelio Muttoni","doi":"10.1016/j.engstruct.2025.120123","DOIUrl":"10.1016/j.engstruct.2025.120123","url":null,"abstract":"<div><div>The anchorage of reinforcement in concrete is a complex phenomenon typically governed by several failure modes, including: pull-out failure, splitting, side spalling, edge wedge spalling, and corner spalling, depending on multiple factors. Extensive research has focused on the first four failure modes, however there is little detailed information in the literature regarding corner spalling. This paper presents an investigation aimed at better understanding the mechanical response and performance of anchorages in concrete corners. The investigation involves a series of inner-pressure tests performed with hydraulic inflator devices in cylindrical openings and pull-out tests on anchorages positioned near the corner. The effects of parameters commonly adopted in engineering practice are investigated, including concrete cover, casting position, confinement index, and anchorage length. Through detailed measurements, insights into the local and global behaviour, resistance, and failure mechanisms of corner anchorages are gained and thoroughly discussed. The results are further compared with the response of edge anchorages which failed due to wedge spalling, demonstrating that the effect of the casting position is less significant for corner anchorages than that for edge anchorages, as the inclined cracking plane caused by pressure does not align with sub-horizontal settlement cracks. Additionally, corner anchorages exhibit smaller resistances than edge anchorages with similar covers and lengths, due to limited stress redistribution capacity and more brittle behavior. On that basis, a mechanical model for calculating the corner spalling resistance is developed and validated, showing consistent agreement with the experimental results, which can be regarded as a step forward in the development of a unified mechanical model for anchorages that fail in different modes. This study underscores that Eurocode 2 (FprEN 1992–1–1:2023) tends to provide unconservative predictions for corner anchorages.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120123"},"PeriodicalIF":5.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654754","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":"A rapid identification framework for post-earthquake local damage of the multi-span interconnected slender equipment in substation","authors":"Jiayi Wen ,&nbsp;Huayi Zhou ,&nbsp;Xiaoxuan Li ,&nbsp;Yantai Zhang","doi":"10.1016/j.engstruct.2025.120124","DOIUrl":"10.1016/j.engstruct.2025.120124","url":null,"abstract":"<div><div>Substation equipment is interconnected through conductors to form a large-scale multi-span system. During an earthquake, individual equipment pieces may suffer local damage that is not visible. Due to the structural integrity of a system, the seismic response is extremely insensitive to the local damage. Thus, the local damage is difficult to detect with traditional time-domain or vibration-mode methods. This hinders the rapid post-earthquake recovery of substations, exacerbating the earthquake-induced losses. This study is based on a generalized transfer matrix in the frequency domain to decouple and eliminate the effects of structural integrity. By inputting the measured displacement responses of equipment during an earthquake into the transfer matrix and inversely calculating, a key indicator <em>EG</em>, the relative error between the theoretically calculated and the actual ground motions experienced by each equipment piece can be obtained. The <em>EG</em> is highly sensitive to locally damaged equipment pieces and has a monotonic relationship with the degree of damage, enabling damage localization and quantitative assessment of stiffness degradation. Based on this principle, a rapid identification framework is proposed. Applying the framework to the randomly generated damage scenarios, it is demonstrated to effectively identify various damage modes, including single-component and multi-component damage within the system. The accuracy of damage localization is 100 %, and the quantitative estimation error for the damage degree is almost within ± 5 %. This framework provides a new path for rapidly identifying post-earthquake damage in substation equipment systems.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120124"},"PeriodicalIF":5.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654796","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":"Influence of slenderness on confining effect of axially loaded circular CFST columns with high-strength materials","authors":"Ci Song ,&nbsp;Yan-Bo Wang ,&nbsp;Guo-Qiang Li ,&nbsp;J.Y. Richard Liew","doi":"10.1016/j.engstruct.2025.120041","DOIUrl":"10.1016/j.engstruct.2025.120041","url":null,"abstract":"<div><div>To investigate the influence of slenderness on the confining effect of circular concrete-filled steel tube (CFST) columns with high-strength materials, 20 tests on CFST slender columns with varying slenderness were carried out. As the increase in slenderness, the confining pressure at the mid-height section decreases and exhibits an uneven distribution across the section, which is attributed to the increasing bending moment introduced by second-order effect. To further investigate the effects of slenderness, concrete strength, and yield strength of steel tubes on the load-bearing capacity of the CFST slender columns, a parametric analysis was conducted. A three-dimensional constitutive model was adopted in the finite element model to simulate the distribution of confining pressure and the axial stress of concrete and steel tubes more precisely. The results indicate that with the increase in slenderness, the establishment of confining pressure is delayed with the magnitude reduced. When the relative slenderness is less than 0.5, the confining pressure is still effective with the strength enhancement index no less than 1. However, while the relative slenderness exceeds 1.0, the confining effect becomes negligible. The reduction factor, defined as the ratio of the load-bearing capacity of the slender column to that of the short column, is derived from the analysis. When comparing the CFST columns infilled with different grades of concrete, the reduction factor for CFST columns filled with normal-strength concrete (NSC) is lower than that for CFST columns filled with ultra-high-performance concrete (UHPC) because the former is more sensitive to confining pressure. The increasing yield strength of steel tubes contributes to enhancing the load-bearing capacity of CFST columns, however, the efficiency decreases with the increase in slenderness. Finally, a reduction factor accounting for the confining pressure is introduced, providing a comprehensive consideration of the confining effect related to slenderness on the load-bearing capacity of CFST slender columns. This analysis applies to steel tubes with a grade of up to Q890 and concrete with a compressive strength of up to 150 MPa.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"333 ","pages":"Article 120041"},"PeriodicalIF":5.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685546","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}