Engineering Structures最新文献

{"title":"Performance of inter-module connection with a pegged tenon for composite modular buildings with CFST columns","authors":"Chao Hou,&nbsp;Qi Qi,&nbsp;Jiahao Peng","doi":"10.1016/j.engstruct.2025.119824","DOIUrl":"10.1016/j.engstruct.2025.119824","url":null,"abstract":"<div><div>The global rise of modular building, with its standardized manufacturing, faster construction, and superior quality, has been a significant trend. Steel-concrete composite modular buildings are emerging as a promising solution to address the increasing capacity demand resulting from the growing design height of modular buildings in various applications, including residential buildings, hotels, and offices. The use of concrete-filled steel tubular (CFST) columns effectively increases the capacity of modular units. However, this also results in higher load demand for inter-module connections, posing a significant challenge for conventional designs. This paper introduces a new tenon-connected inter-module connection for composite modular buildings, in which the tenon is pegged with tightening bolts driven through it perpendicularly. This innovative design offers a reliable load path to ensure continuity between the connected columns, while also allowing for easy assembly. An experimental test was conducted on six full-scale connection specimens to study their structural performance under monotonic loading. Four distinct failure modes were observed, and the corresponding load-displacement relation and strain distribution were thoroughly evaluated. A detailed finite element analysis (FEA) model was developed and validated against test data, which was then used to conduct a parametric study to investigate the influence of key parameters on the connection performance. The study revealed that variations in the column, brace, and tenon parameters greatly influenced the connection failure mode and loading capacity. The findings of this study provided a reference for the safe design of novel inter-module connections for composite modular buildings.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119824"},"PeriodicalIF":5.6,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143142091","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":"Splice length and bond behaviors of doubled-row lapped bars in ultra-high performance concrete (UHPC)","authors":"Zhiyan Wu ,&nbsp;Mingke Deng ,&nbsp;Mengna Jin ,&nbsp;Xinlong Wang ,&nbsp;Hao Lyu","doi":"10.1016/j.engstruct.2025.119840","DOIUrl":"10.1016/j.engstruct.2025.119840","url":null,"abstract":"<div><div>This study investigated the bond behavior of hot-rolled ribbed bar (HRB) 500 in ultra-high performance concrete (UHPC) through direct tension tests on 11 groups of double-row spliced specimens. The variables included splice length, cover thickness, matrix type, fiber volume content, spacing between lapped bars, bar diameter, and bar grade. In addition, seven groups of anchorage specimens were designed to examine the differences between the two specimen types. Results indicate that the bond strengths of the spliced test ranged from 0.45 to 0.86 times those of the central pullout tests. The bond strength in spliced specimens was less affected by embedded length compared to anchorage specimens; however, it increased more significantly with a greater cover thickness. A size effect related to rebars was observed in the spliced specimens, whereas it was absent in anchorage specimens. The bond strength of UHPC with 2 % fiber was approximately twice that of ordinary concrete, but increased slowly when the fiber content increased to 3 %. A splice length of 12<em>d</em> led HRB 500 rebar (20 mm diameter) to yield, and a cover thickness of 3.8<em>d</em> was recommended to ensure yielding of a bar with a 3<em>d</em> splice length. A theoretical equation for calculating the UHPC bond strength was proposed that consider the bundle effect of bar lapping. Finally, a calculation model for predicting the yield splice length derived from the nonuniform bond stress distribution model, which aligned well with the experimental results of UHPC bond from existing studies.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119840"},"PeriodicalIF":5.6,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143142093","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":"Investigation on fatigue performance and life prediction of PBL connectors in steel-UHPC composite structure","authors":"Yang Liu ,&nbsp;Lin Xiao ,&nbsp;Xing Wei ,&nbsp;Xuan Liao ,&nbsp;Shigang Wang","doi":"10.1016/j.engstruct.2025.119762","DOIUrl":"10.1016/j.engstruct.2025.119762","url":null,"abstract":"<div><div>This paper presents an investigation into the fatigue performance and life prediction of perfobond strip connectors (<em>PBLs</em>) in steel-ultra-high performance concrete (<em>UHPC</em>) composite structure, based on three static push-out tests and nine fatigue tests. From the three static push-out tests results, the fatigue load and load amplitude for fatigue tests are determined. A comparative analysis is then conducted on the fatigue life, failure modes, slip curves, shear stiffness degradation laws and failure mechanisms of PBL connectors under static and fatigue loading conditions. Two-stage fatigue cumulative damage mode applicable to PBL connectors in UHPC is then proposed. Finally, based on above analysis, the fatigue life prediction model of the PBL connectors in UHPC is proposed and validated by experimental results. The results indicate that the load amplitude remains the primary factor affecting the fatigue life of PBL connectors. The fatigue cumulative damage of PBL connectors in UHPC is more unstable compared to that of PBL connectors in normal concrete, showing three-stage fatigue cumulative damage under small load amplitude and five-stage fatigue cumulative damage under large load amplitude. The final failure mode of PBL connectors in UHPC under static and fatigue test is characterized by the fracture of the transverse rebar, whereas in normal concrete, the failure mode primarily involves the crushing and splitting of the concrete slab at the PBL connectors. The fatigue damage of PBL connectors in UHPC more accurately is divided into two stages: the UHPC-dominated damage stage and the transverse rebar-dominated damage stage. The fatigue life prediction model of PBL connectors is proposed and validated by experimental results.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119762"},"PeriodicalIF":5.6,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141487","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":"Automatic detection of subsurface defects in concrete structures using state-of-the-art deep learning-based object detectors on the infrared dataset","authors":"Quang Tai Ta ,&nbsp;Van Ha Mac ,&nbsp;Jungwon Huh ,&nbsp;Hong Jae Yim ,&nbsp;Giyeol Lee","doi":"10.1016/j.engstruct.2025.119829","DOIUrl":"10.1016/j.engstruct.2025.119829","url":null,"abstract":"<div><div>Coupling infrared thermography (IRT) with deep learning is a potential approach to address the limitations of conventional IRT-based concrete delamination identification. However, it remains under-explored, mainly due to the scarcity of infrared data. This study examined numerous advanced object detectors, including Faster R-CNN, SSD, and the variants of YOLO versions (YOLOv5, YOLOv6, YOLOv7, YOLOv8, YOLO-NAS, and YOLOv9) to comprehensively evaluate their applicability on a self-prepared infrared dataset comprising 12,000 images of artificial defects. The results demonstrated that most of the selected models worked efficiently on the IRT dataset with precision, recall, F1-score, and AP₅₀ greater than 91 % and real-time speeds higher than 45 FPS. The effectiveness of each model was elucidated, and the most suitable frameworks for delamination detection systems were proposed. Interestingly, newer versions of the selected YOLO models failed to surpass their predecessors. Moreover, larger variants did not outperform smaller ones within each YOLO version. Additionally, the effects of various IRT experimental conditions, image processing techniques, and data augmentation strategies on the model’s performance were thoroughly investigated. Consequently, the capabilities and limitations of the automated approaches presented in this work form a solid foundation for further studies on automatically detecting internal defects in concrete structures using deep learning models and IRT inspection data.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119829"},"PeriodicalIF":5.6,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141518","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":"Instability of compressed members in timber trusses assembled with punched metal plates","authors":"Angelo Aloisio ,&nbsp;Petr Sejkot ,&nbsp;Matteo Pelliciari ,&nbsp;Sigurdur Ormarsson ,&nbsp;Johan Vessby ,&nbsp;Massimo Fragiacomo","doi":"10.1016/j.engstruct.2025.119775","DOIUrl":"10.1016/j.engstruct.2025.119775","url":null,"abstract":"<div><div>This study addresses the instability of wooden trusses assembled with punched metal plates. The instability of compressed wooden elements is a complex problem due to the specific boundary conditions, the timber orthotropy, and the difficult quantification of the defects. This research presents an analytical framework based on the Eurocode approach for predicting the instability of compressed wooden elements, considering the effect of boundary constraints representative of punched metal plates. The general aspects of this research are twofold: (i) proposing an analytical approximate expression for assessing the theoretical buckling load of compressed beams with elastic boundary constraints; (ii) deriving the buckling design curves as a function of the geometric imperfection of the structural element. The authors refer to the constraints exerted by punched metal plates, experimentally characterized to determine the response along the six degrees of freedom. The experimental results were used to generate a high-fidelity finite element (FE) model of the connection, validate it using digital image correlation, and estimate by extrapolation the stiffness properties of a selection of punched metal plates. Additionally, a secondary FE model was developed to simulate the out-of-plane deflection of structural elements with different types of punched metal plates, predict the failure load from static incremental analysis, and estimate the buckling design curves. In conclusion, the research aims to specialize the design method of compressed members according to the Eurocode, taking explicitly into account the boundary constraints representative of punched metal plates. It is found that while the theoretical instability load of beams with elastic constraints closely approximates that of the clamped condition, the instability load under imperfections resembles the pinned condition more closely. This observation leads to systematically higher imperfection coefficients for elastic constraints than pinned conditions.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119775"},"PeriodicalIF":5.6,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141486","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":"Experimental and numerical investigation on ductile fracture behavior of welded areas under tensile and shear forces","authors":"Yifei Wang ,&nbsp;Lewei Tong ,&nbsp;Weizhou Shi","doi":"10.1016/j.engstruct.2025.119802","DOIUrl":"10.1016/j.engstruct.2025.119802","url":null,"abstract":"<div><div>Due to complex stress conditions, welded joints in steel and concrete-filled steel tubular trusses are considered weak parts and are susceptible to failure by fracture. To investigate the ductile fracture behavior of steel tubular welded joints under a combination of tension and shear, this study took 36 specimens from the base/tube metal (BM), heat-affected zone (HAZ) and weld metal (WM) in welded areas. The fracture behavior of five kinds of specimens were compared. Then, to simulate fracture patterns of specimens, this study developed a new Shear-Modified GTN model (SMGTN), which was based on two types of damage variables: tension and shear. The particle swarm optimization (PSO) algorithm was employed to calibrate SMGTN model parameters. Finally, the stress conditions, damage, and fracture patterns of various specimens were analyzed. The result demonstrated that the larger the radius or shear center rotation angle of notched specimens, the larger the fracture displacement. The materials in BM, HAZ, and WM regions exhibited different ductile behavior under different stress conditions. The calibrated parameters of SMGTN model in this study accurately predicted the fracture displacement and development patterns in the BM, HAZ, and WM regions.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119802"},"PeriodicalIF":5.6,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141485","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":"Machine vision-based technology for the interface classification of precast concrete components","authors":"Yong Zhao ,&nbsp;Zhiyan Wang ,&nbsp;Jisong Liu ,&nbsp;Boyu Zhang","doi":"10.1016/j.engstruct.2025.119835","DOIUrl":"10.1016/j.engstruct.2025.119835","url":null,"abstract":"<div><div>The interfaces of precast concrete components serve as connections between components. The quality of these interfaces affects not only the bonding strength between the components but also the seismic performance of the entire structure. Therefore, the quality of the interface construction is a crucial factor in ensuring the safety and longevity of engineering projects. To enhance the reliability and objectivity of the inspection results of interface quality, this study introduced machine vision technology and investigated intelligent inspection approaches for interface construction quality, achieving the identification of two hierarchical key targets: construction techniques and roughness grades. First, this study integrated a specialized detection device to collect substantial images in a constrained environment, establishing a stable dataset called the Concrete Techniques and Roughness (CTR) dataset. Second, this study employed a hierarchical Convolutional Neural Network (CNN) structure in which layers make predictions in the descending order of class abstraction based on prior knowledge. This allows the model to classify sequentially according to construction techniques and roughness grades. Additionally, considering the characteristics of interfaces, this study introduced the Fused Strip Pooling and Convolutional (FSPC) attention module as a feature fusion attention mechanism that enhances the ability of the model to focus on the crucial quality features of interfaces. The integration of hierarchical prior knowledge and attention mechanisms significantly improved the classification performance. This approach achieved an accuracy of 100 % for the construction techniques and 96.26 % for the roughness grades on the testing set of the CTR dataset. The results demonstrate that this method provides an effective solution for the application of machine vision in the quality inspection of precast concrete component interfaces.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119835"},"PeriodicalIF":5.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141603","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":"Mechanical analysis of the high bolt screw (HBS) active joint under eccentric loading for prestressed internal support in subway excavation","authors":"Chenhe Ge,&nbsp;Pengfei Li,&nbsp;Mingju Zhang,&nbsp;Ze Li","doi":"10.1016/j.engstruct.2025.119837","DOIUrl":"10.1016/j.engstruct.2025.119837","url":null,"abstract":"<div><div>This paper presents a novel high bolt screw (HBS) active joint engineered to enhance eccentric tensile and compressive support within subway deep foundation pits, thereby bolstering underground structural stability and safety. This comprehensive investigation of the HBS active joint design included an overview, operational principles, stiffness analysis, parameters, and strength verification. To assess the load-bearing and bending capacities of HBS joints accurately under eccentric loading conditions, a series of indoor loading tests were conducted on two joints. The resulting data included load<img>displacement, moment<img>rotation, and load<img>strain curves and failure modes. The results of the numerical simulations closely matched the laboratory results, verifying their reliability. Parametric studies were then performed to examine how different design parameters affect eccentric compression and bending. The findings revealed that the yield load and moment resistance depend on the eccentric distance but not the angle. The load-bearing and bending performance of a joint is positively correlated with parameters such as the screw diameter, extension length, barrel nut height and thickness, and steel tube thickness, although the impact of each parameter varies. Accurate formulae for calculating the moment resistance and initial rotational stiffness were derived, yielding a reliable moment<img>rotation model. These results highlight the exceptional load-bearing and bending capacities of HBS joints, offering key insights into the design of advanced support systems for subway foundation pits.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119837"},"PeriodicalIF":5.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141606","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":"Compression-torsion coupling auxetic tubular structures with enhanced stability","authors":"Jun Wen Shi,&nbsp;Wei Zhong Jiang,&nbsp;Yi Zhang,&nbsp;Yi Chao Qu,&nbsp;Xiao Ji,&nbsp;Jian Hao,&nbsp;Han Yan,&nbsp;Xin Ren","doi":"10.1016/j.engstruct.2025.119803","DOIUrl":"10.1016/j.engstruct.2025.119803","url":null,"abstract":"<div><div>Auxetic materials exhibit exceptional mechanical properties and distinctive deformation characteristics. A novel compression-torsion coupled auxetic tube is introduced in this study, which integrates an auxetic structure with a compression-torsion coupling mechanism. By modifying the inner tube and ribs of the structure, the compression-torsion coupling effect is enhanced, improving both the mechanical properties and deformation characteristics. Three compression-torsion coupled auxetic tubes (CATs) were fabricated using 3D printing technology. They were compared with conventional auxetic tubes (AT) to examine the influence of compression-torsion coupling on structural behavior. Experimental results were compared with simulation, confirming the validity of the finite element model. Numerical analysis was conducted to investigate the influence of the direction of compression-torsion coupling and outer wall thickness on CAT structures. The results demonstrate that the compression-torsion coupling effect changes the wall thickness under compression, enhancing energy absorption and structural stability. The structure has a densification delay of 28.5 % compared to other perforated tubes, and the SEA has increased by 105 %. Additionally, the application of compression-torsion coupled auxetic tubes in auxetic springs was explored, revealing that the compression-torsion coupling effect significantly prolongs the working displacement of the structure while improving its capacity for elastic energy storage. CAT has broad application prospects in the fields of soft robots and protective engineering.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119803"},"PeriodicalIF":5.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141607","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 reliability of low-prestressed self-centering braces considering steel dissipater fracture","authors":"Ying Zhou,&nbsp;Honghao Bai,&nbsp;Yi Xiao","doi":"10.1016/j.engstruct.2025.119816","DOIUrl":"10.1016/j.engstruct.2025.119816","url":null,"abstract":"<div><div>Low-Prestressed Self-Centering (LPSC) braces are newly developed brace systems which limits both seismic peak and residual deformations, with a low requirement of prestressing forces. These systems utilize ratchet components to minimize the resistance from dissipaters to re-centering systems. Two types of LPSC braces, i.e., Symmetric Hysteresis LPSC (SH-LPSC) brace and Tension-Only LPSC (TO-LPSC) brace, have three common features of their steel dissipaters: 1) occupy a small portion of the entire brace; 2) slender; 3) made by carbon-steel. These characteristics denote a new challenge, that the seismic elongation demand (which cumulates in cyclic loadings) might exceed their limited capacity of steel dissipaters. To secure the use of LPSC braces, this study focuses on evaluating the seismic reliability of LPSC braces considering the fracture of steel dissipaters. First, the elongation capacity of carbon-steel dissipaters, which was adopted in previous studies, and stainless-steel dissipaters, which was proposed, were experimentally investigated. Then, numerical models for both LPSC systems were developed and used to calculate the elongation demand of LPSC systems under mainshocks and mainshock-aftershock sequences through nonlinear dynamic analyses. Based on the numerical results, a mathematic model was developed to predict the elongation demand of steel dissipater. Furthermore, the seismic reliabilities of the two LPSC systems with carbon- and stainless-steel dissipaters were investigated by comparing the elongation demand of steel dissipaters against their capacity in a probability manner. Results indicate that SH-LPSC systems have a higher reliability than TO-LPSC systems because it has lower probability of steel dissipaters fracture at certain drifts. When carbon-steel dissipaters were used, LPSC systems showed a high fracture likelihood, particularly under mainshock-aftershock sequences (15.29 % for SH-LPSC and 27.92 % for TO-LPSC systems). Conversely, stainless-steel dissipaters consistently exhibited near-zero fracture probabilities. Overall, adopting stainless-steel dissipaters substantially reduces brace failure risks, thereby enhancing the seismic reliability of LPSC braces.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"329 ","pages":"Article 119816"},"PeriodicalIF":5.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143141481","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}