Structures最新文献

{"title":"Compressive and flexural properties of engineered geopolymer composites incorporating dune sands","authors":"Tianhe Zhang ,&nbsp;Qinghe Wang ,&nbsp;Qingxin Ren ,&nbsp;Tong Li ,&nbsp;Haoyue Sun ,&nbsp;Ji-nan Ding","doi":"10.1016/j.istruc.2025.109251","DOIUrl":"10.1016/j.istruc.2025.109251","url":null,"abstract":"<div><div>The integration of dune sand (DS) into engineered geopolymer composites (EGCs) has been shown to enhance their mechanical properties while simultaneously reducing dependence on ultrafine silica sand (SS), thereby contributing to cost-effective production. The study analyzes the effects of DS replacement ratios on EGC compressive and flexural properties across varying NaOH concentrations. Microstructural analysis, conducted using scanning electron microscopy (SEM), provides insights into the mechanisms underlying these improvements. Incorporating DS significantly boosts compressive and flexural strengths as well as toughness. The improvements stem from DS's pozzolanic activation at optimal NaOH levels, fostering secondary hydration and densifying the matrix. Maximum performance is recorded at 20 % NaOH, where DS addition enhances compressive strength by 18.18 %, flexural strength by 35.19 %, and midspan deflection to 105.27 mm. DS improves the fiber-matrix bond, enabling multiple cracking and strain-hardening. This enhanced fiber-matrix interaction contributes to superior energy absorption and improved ductility. To further characterize the mechanical behavior of EGCs, a refined stress-strain model is proposed, offering an accurate representation of both pre-peak and post-peak responses under uniaxial compression.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109251"},"PeriodicalIF":3.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168267","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":"Novel external dissipative device for rocking bridge columns: Resilient rotational friction elements","authors":"Hamdy Farhoud,&nbsp;Anthony Mackin,&nbsp;Islam M. Mantawy","doi":"10.1016/j.istruc.2025.109317","DOIUrl":"10.1016/j.istruc.2025.109317","url":null,"abstract":"<div><div>Rocking columns with internal reinforcement face challenges such as inelastic buckling, fracture due to low-cycle fatigue, and complex repair processes, which can compromise their resiliency after seismic events. This paper introduces the resilient rotational friction element (RRFE), an innovative external dissipative device designed to overcome inherent limitations in these rocking columns. By integrating controlled rotational friction mechanisms and self-centering prestressed strands, the RRFE enables damage-free seismic energy dissipation with superior structural resilience. Experimental evaluation under monotonic and cyclic loading validated the RRFE's robustness and energy dissipation capabilities. Monotonic tests demonstrated the influence of torque levels on frictional resistance with friction energy increasing from 0.10 to 1.11 kips·in, reflecting an 11-time increase when transitioning from snug-tightened to a 40 lb·ft torque level. A mechanistic model developed from monotonic tests provides predictive accuracy for friction energy design. Additionally, a theoretical framework was established to derive the rotational moment <em><strong>(M</strong></em>_{<em><strong>R</strong></em>}<em><strong>)</strong></em> based on Coulomb’s friction law and stress distribution principles. The developed equations, validated against experimental results, accurately capture the relationship between applied torque and axial post-peak behavior, providing a reliable tool for optimizing RRFE performance. Cyclic tests highlighted consistent energy dissipation and post-buckling performance across different specimens. Higher torque levels resulted in increased energy dissipation. The RRFE's adaptable design suits rocking systems such as concrete walls, steel columns, and mass timber walls, offering a cost-effective solution for new construction and retrofitting. This paper confirms the RRFE's potential as a transformative advancement in seismic-resistant design, addressing conventional system drawbacks and providing an efficient, repairable, and resilient solution for seismic-resistant structures.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109317"},"PeriodicalIF":3.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170717","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":"Axial compressive behavior of concrete-filled double-skin steel tubular columns with localized cracks","authors":"Tong Zhang ,&nbsp;Shiqi Huang ,&nbsp;Shan Gao","doi":"10.1016/j.istruc.2025.109302","DOIUrl":"10.1016/j.istruc.2025.109302","url":null,"abstract":"<div><div>Concrete-filled double-skin steel tubular (CFDST) columns are widely used in a wide range of applications such as high-rise buildings, long-span bridges, offshore platforms, and heavy-duty industrial structures. However, due to the exposed steel tube, the external steel tube of CFDST columns is prone to cracking during long-term service, which affects their normal and safe use. This paper presents the mechanical behavior of CFDST columns with localized cracks. The peak load, failure mode, and full-range load-strain curve were produced according to the FE (finite element) model which were all line up with the findings of the experimental study. The impact of localized cracks on the CFDST stub struts in terms of peak load, stiffness, and flexibility is evaluated. The results indicate that the crack length, crack width, and crack depth exert minimal influence on the ultimate load and stiffness of the specimen. The crack length, crack width, and crack depth significantly impact the specimen's ductility. The ductility of the specimen is rapidly reduced by 30.9 %, especially when the steel tubes are penetrated due to corrosion. The crack angle barely impacts the breaking strength of the specimen. As the crack angle increases, the stiffness gradually decreases and the ductility gradually increases. A predictive technique of an error of less than 6 % is shown for the axial compressive capacity of CDFST pile columns with localized cracks. Finally, the GA-BP neural network model demonstrates its improved accuracy and generalization ability by comparing the genetic algorithm to a standard BP neural network, exhibiting higher the coefficient of determination and lower prediction errors on training and test datasets.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109302"},"PeriodicalIF":3.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168269","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":"Flexural ductile behavior of glued laminated bamboo (glubam) beams equipped with steel fuse bars","authors":"Mohamed Adel ,&nbsp;Hongyi PAN ,&nbsp;Bibin Wang ,&nbsp;Yan Xiao","doi":"10.1016/j.istruc.2025.109279","DOIUrl":"10.1016/j.istruc.2025.109279","url":null,"abstract":"<div><div>Glued laminated bamboo (glubam) is an engineered material known for its high strength and sustainability. However, its inherent susceptibility to brittle flexural failure and limited ductility raises significant concerns regarding the safety and robustness of glubam structures. This study addresses these limitations through experimental, theoretical, and numerical investigations on the flexural ductile behavior of pre-cracked thin-strip glubam beams equipped with steel fuse bars. Pre-cracks were introduced at the mid-span to promote the yielding of fuse bars at their weakened core sections before the beam’s failure. Four series of beams were tested under a four-point bending load, with and without fuse bars, varying in bar lengths and pre-crack configurations. The experimental results revealed a significant enhancement in ductility for pre-cracked beams with fuse bars, with the GB-LR1C series exhibiting a 2.5-fold improvement. However, pre-cracking led to a reduction in load-bearing capacity by approximately 45 %. These findings were validated through theoretical models and numerical simulations, which accurately predicted the initial stiffness, mid-span deflection, curvature, ductility, and flexural capacity. Parametric analyses were further conducted to emphasize the influence of fuse bar configuration and pre-crack characteristics on optimizing the flexural performance of beams, providing valuable insights into a robust structural design of glubam.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109279"},"PeriodicalIF":3.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170714","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":"Amplified viscously damped coupling beam (AVDCB): A high-efficiency seismic damping solution for coupled wall structures","authors":"Zheng Luo ,&nbsp;Jianyang Xue ,&nbsp;Yan Sui ,&nbsp;Chengyu Bai ,&nbsp;Liangjie Qi ,&nbsp;Hong Pan","doi":"10.1016/j.istruc.2025.109319","DOIUrl":"10.1016/j.istruc.2025.109319","url":null,"abstract":"<div><div>This paper introduces a fully open-space damping amplification scheme, the Amplified Viscously Damped Coupling Beam (AVDCB). The AVDCB integrates a lever-arm amplifier into a standard viscous damped coupling beam (VDCB), utilizing a leverage ratio as a controllable amplification factor to enhance the damper performance during earthquakes. Dynamic cyclic loading tests are performed on both AVDCB and VDCB specimens to assess their hysteretic behavior. Numerical models, validated against experimental data, are developed, and a parametric study examines the impact of amplification factors and damper parameters on the AVDCB’s performance enhancement relative to the VDCB. Seismic response and damage mitigation of AVDCB are further assessed through time-history analysis of a 20-story building. The results show that the AVDCB significantly increases viscous damper deformation and velocity, leading to a marked increase in shear force and energy dissipation compared to the VDCB with identical dampers. The amplification effect of AVDCB is most pronounced when higher amplifier’s amplification factors and damper’s damping exponents are employed, although excessively high damping exponents may lead to excessive outputs under intense shaking. The equivalent relationship between the AVDCB and VDCB is established through an energy dissipation equilibrium, revealing that the AVDCB achieves seismic mitigation more efficiently than VDCB by using smaller damper sizes. A case study shows that AVDCB, compared to conventional RC coupling beams, reduces peak roof acceleration by over 50 %, and both base shear and structural deformation by more than 35 % under frequent-level earthquakes. Under rare-level earthquakes, base shear and structural deformation are reduced by over 24 %, providing significant damage protection. This highlights that the proposed AVDCB offers a highly efficient and space-friendly solution for improving seismic resilience of coupled wall structures.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109319"},"PeriodicalIF":3.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170716","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":"Structural behaviour and design of concrete-filled stainless steel tubular stub columns with circular and square cross-sections subjected to combined compression and bending","authors":"Peng Dai ,&nbsp;Lu Yang ,&nbsp;Linbo Zhang ,&nbsp;Huiyong Ban","doi":"10.1016/j.istruc.2025.109162","DOIUrl":"10.1016/j.istruc.2025.109162","url":null,"abstract":"<div><div>This study investigates the structural behaviour of concrete-filled stainless steel tubular (CFSST) stub columns with circular and square cross-sections under combined compression and bending loads. Finite element models were developed and validated against experimental results of 20 CFSST stub columns, achieving good agreement in predicting the ultimate bearing capacities and failure modes. The validated FE models were employed to conduct extensive parametric studies, providing insights into the effects of key parameters, including wall thickness, concrete strength, and load eccentricity on the structural behaviour of CFSST stub columns. It has been found that increasing the wall thickness increases the load-bearing capacity of CFSST stub columns; increasing the concrete strength increases the load-bearing capacity but decreases the normalized load-bearing capacity; increasing the load eccentricity decreases the load-bearing capacity. Furthermore, it has been revealed that existing design codes (Eurocode 4, ANSI/AISC 360-22, and GB 50936-2014) tend to provide conservative predictions for the load-bearing capacities of CFSST columns due to neglecting the strain-hardening properties of stainless steel in the design approaches. Therefore, an approach was proposed by modifying the Continuous Strength Method (CSM) to enhance the accuracy of design predictions for CFSST columns under combined loading conditions.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109162"},"PeriodicalIF":3.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168283","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 assessment of masonry churches through combined modal and pushover analysis","authors":"Marialaura Malena,&nbsp;Mario Lorello,&nbsp;Gianmarco de Felice","doi":"10.1016/j.istruc.2025.109281","DOIUrl":"10.1016/j.istruc.2025.109281","url":null,"abstract":"<div><div>The paper proposes a novel procedure for the seismic assessment of ancient masonry churches. The procedure stems from the idea that the study of the linear dynamic behaviour of the building as a whole can help to gather information on the portions of the building most vulnerable in the event of an earthquake. The proposed procedure consists of several steps, the first of which is the modal analysis of the entire structure, which becomes the tool through which to define a series of simplified non-linear static analyses, performed on the whole structure and able of capturing the collapse load associated with the mechanisms. The procedure is first validated through comparison with the results of an experimental campaign and, subsequently, adopted to study the seismic behaviour of the church of St. Martino dei Gualdesi (Castelsantangelo - Italy), significantly hit by the 2016–2017 Central-Italy earthquake, and the church of St. Nicolò di Capodimonte in Camogli (Genova - Italy), studied in a previous work by the Authors <span><span>[1]</span></span>.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109281"},"PeriodicalIF":3.9,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168266","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":"Mesoscale numerical investigation of chloride transport in recycled aggregate concrete considering calcium leaching: Multi-phase and multi-interface","authors":"Tian Wu,&nbsp;Libing Jin,&nbsp;Hualong Yu,&nbsp;Linran Qiao,&nbsp;Yun Zhao,&nbsp;Pin Zhou","doi":"10.1016/j.istruc.2025.109307","DOIUrl":"10.1016/j.istruc.2025.109307","url":null,"abstract":"<div><div>Chloride penetration and calcium leaching (C-L) combine to induce steel corrosion, which is the primary cause of the declining durability of recycled aggregate concrete (RAC). A multiphase numerical model was developed to investigate the diffusion behavior of chloride ions in RAC, considering C-L, the presence of multiple interfacial transition zones, and the time-varying diffusion coefficients of different components. The model was validated through chloride ion erosion experiments. Additionally, the relationship between chloride ion transport and the temporal-spatial distribution of porosity was explored. The results show that: 1) At a certain exposure depth, the chloride ion concentration is relatively high when considering C-L. After approximately three years of exposure, the failure thickness without considering C-L is approximately 4.71 mm less than with C-L. 2) Diffusion coefficient multipliers <span><math><mrow><mi>H</mi><mrow><mfenced><mrow><mi>t</mi></mrow></mfenced></mrow></mrow></math></span> and <span><math><mrow><mi>H</mi><mrow><mfenced><mrow><mi>φ</mi></mrow></mfenced></mrow></mrow></math></span> were negatively and positively correlated with time, respectively. 3) As erosion time increased from 180 to 1080 days, the leaching extent increased from approximately 25 mm to 50 mm. Additionally, porosity showed an upward trend from the internal leach surface to the exposed surface due to the effect of C-L. This study can serve as a reference for further in- depth research on chloride ion transport in RAC.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109307"},"PeriodicalIF":3.9,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147760","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":"Mapping and revealing the nature of masonry compressive strength using computational intelligence","authors":"Panagiotis G. Asteris ,&nbsp;Georgios Α. Drosopoulos ,&nbsp;Liborio Cavaleri ,&nbsp;Antonio Formisano ,&nbsp;Anastasios Drougkas ,&nbsp;Gabriele Milani ,&nbsp;Amin Mohebkhah ,&nbsp;Paulo B. Lourenço","doi":"10.1016/j.istruc.2025.109189","DOIUrl":"10.1016/j.istruc.2025.109189","url":null,"abstract":"<div><div>The compressive strength of masonry walls constitutes a significant parameter that strongly influences the structural response of masonry buildings, under either static or dynamic actions. Significant variability is observed in the range of compressive strength values as highlighted by existing experimental investigations. Empirical relations providing the compressive strength also feature significant prediction divergence. This is attributed to large variations in the geometry and type of units, joint thicknesses, materials and building practices. Therefore, the need arises for the accurate prediction of the compressive strength of masonry walls, using data which is accumulated from past experiments. Artificial intelligence tools and machine learning techniques are considered in this study, to leverage the experience from those past experiments in predicting the compressive strength. A dataset of 611 specimens is developed, to the authors’ best knowledge comprises the largest dataset assembled for this purpose to date. Different Back Propagation Neural Networks models are trained and tested using the new dataset, leading to an optimal machine learning architecture. Results indicate that the optimal model can provide an improved prediction of the compressive strength as compared to literature proposals. Parameters which drastically affect the compressive strength are highlighted and expressions predicting the compressive strength are discussed.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109189"},"PeriodicalIF":3.9,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168284","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":"Experimental and numerical study of a novel double-stage capacity-adjustable buckling-restrained brace","authors":"Liang Cai ,&nbsp;Shaofeng Wu ,&nbsp;Kaiqi Lin ,&nbsp;Zuoxuan Sun ,&nbsp;Weidong Zhuo","doi":"10.1016/j.istruc.2025.109275","DOIUrl":"10.1016/j.istruc.2025.109275","url":null,"abstract":"<div><div>To enhance the seismic performance of buckling-restrained braces (BRBs) and meet the requirements for seismic resilience under multi-level earthquakes, this study proposes a novel double-stage capacity-adjustable buckling-restrained brace (CABRB). The CABRB features a sacrificial component and an energy-dissipating BRB working in parallel. During small earthquakes, the sacrificial component provides additional stiffness and strength to ensure structural serviceability. As seismic intensity increases, the sacrificial component fails, helping to concentrate the seismic damage on the BRB component and protecting other structural components. This study first designed and conducted quasi-static tests to evaluate the seismic performance and post-earthquake reparability of the CABRB equipped with various opening-shaped sacrificial plates. Upon the experimental investigations, refined finite element models were established to conduct parametric analyses for evaluating the influences of geometric parameters of the sacrificial plate on the mechanical properties of the CABRB. Additionally, two-story braced frame numerical models, one equipped with BRBs and the other with CABRBs, were established and compared to validate the feasibility and applicability of the CABRBs. The results indicate that the proposed CABRB, with its unique double-stage mechanical behavior, not only meets the multi-level seismic performance requirements, but also exhibits excellent post-earthquake reparability. This provides valuable insights and technical support for the multi-level seismic design of civil structures.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":"78 ","pages":"Article 109275"},"PeriodicalIF":3.9,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147761","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}