Structures最新文献_第8页

Experimental and numerical study on the cyclic behavior of web dumbbell-shaped damper fabricated of low-yield-point steel 低屈服点钢制成的腹板哑铃形阻尼器循环行为的实验和数值研究

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107628

{"title":"Experimental and numerical study on the cyclic behavior of web dumbbell-shaped damper fabricated of low-yield-point steel","authors":"","doi":"10.1016/j.istruc.2024.107628","DOIUrl":"10.1016/j.istruc.2024.107628","url":null,"abstract":"<div><div>Current double-conical steel dampers, mainly made from low-carbon steel, stainless steel or high-strength steel, do not perform well in terms of fatigue, energy dissipation, and plastic deformation. To address these limitations, this study proposes a web dumbbell-shaped damper fabricated of LYP225 low-yield-point steel (LYP-WDP). This innovation aims to significantly improve the hysteretic behavior and fatigue performance of double-conical steel dampers. Given the limited experimental research on the hysteretic behavior of LYP-WDP under cyclic loading, this study conducts tests to evaluate its performance. Seven full-scale LYP-WDP specimens with different structural parameters were designed using LYP225 steel and subjected to low-cycle loading tests to assess their behavior under shear deformation. The effects of various design parameters on the performance of LYP-WDP were thoroughly analyzed. Finite element models of the specimens were created, and the simulation results were compared with experimental data. Additionally, formulas for calculating the elastic stiffness and yield strength of the LYP-WDP were proposed. The findings reveal that LYP-WDP has high ductility and stable energy dissipation capacity. The elastic stiffness and load-carrying capacity of LYP-WDP increase with the internal shrinkage ratio when the inner diameter and length of the energy dissipation segment are constant, while a negative correlation is found when the outer diameter and length are fixed. Increasing the length of the straight segment greatly enhances the energy dissipation capacity of LYP-WDP. The test results validate the accuracy of the proposed formulas and provide valuable insights for the design and application of LYP-WDP, marking a significant advancement in the field of damping technology.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538731","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}

引用次数: 0

Compressive testing and numerical modelling of concrete-filled aluminium tubular stub columns after exposure to high temperatures 混凝土填充铝管桩柱暴露于高温后的抗压测试和数值建模

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107523

引用次数: 0

Research on improved dynamic load identification method based on Kalman filter under noise interference 噪声干扰下基于卡尔曼滤波器的改进型动态负载识别方法研究

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107515

{"title":"Research on improved dynamic load identification method based on Kalman filter under noise interference","authors":"","doi":"10.1016/j.istruc.2024.107515","DOIUrl":"10.1016/j.istruc.2024.107515","url":null,"abstract":"<div><div>As a mathematical approach for solving inverse problems, the dynamic load identification method is particularly useful when directly measuring the load acting on a structure is challenging. The Kalman filter (KF) algorithm is commonly employed for dynamic load identification. However, in practice, measurement noise can significantly affect the accuracy of the KF algorithm's results. In this study, we investigate the impact of response noise on the accuracy of load identification results using the KF algorithm. To eliminate the influence of measurement noise on identification accuracy, we propose an improved dynamic load identification method. This method incorporates adaptive techniques to assess varying levels of response noise and improve the load identification accuracy. Notably, this method is applicable in both physical and modal domains. We conduct numerical simulations using a 5-DOF system under different noise conditions. Compared to traditional dynamic load identification method based on KF algorithm, the improved method consistently achieves superior accuracy in load identification across various noise levels. Moreover, an experiment is conducted to further validate the feasibility of the proposed method. The results showed that the proposed method is effective and can achieve high-precision identification of unknown loads.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538979","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}

引用次数: 0

Seismic behavior of base isolated precast frame 底座隔震预制框架的抗震性能

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107577

{"title":"Seismic behavior of base isolated precast frame","authors":"","doi":"10.1016/j.istruc.2024.107577","DOIUrl":"10.1016/j.istruc.2024.107577","url":null,"abstract":"<div><div>The performance of the base-isolated precast frame is examined for both near-field and far-field earthquakes. For comparison, the corresponding base isolated monolithic frame is analyzed. The frames are isolated using a friction pendulum system (FPS), which is appropriately designed to take up the vertical load coming on the frames. The same isolators are provided for the monolithic and precast frames. Two types of precast frames are considered, namely frames with emulated and non-emulated connections. An ensemble of 7 different earthquakes is used for each type of earthquake to obtain the average responses, which include maximum base shear, maximum acceleration, maximum top story displacement, and maximum inter-story drift ratio (MIDR). SAP2000 is used for the non-linear time history analysis of the frames for different earthquakes. The studies are made for three levels of PGA, namely 0.4 g, 0.6 g, and 0.8 g. The study shows that a significant reduction in base shear, top story displacement and MIDR is achieved by base isolating the precast frames. However, the corresponding base isolated monolithic frame offers more reductions in response especially for MIDR. Of the two types of precast frames, the one with emulated connection shows marginally higher reductions of response as compared to the non-emulated connection. Further, the percentage reductions in responses in main shock and after shock remain almost the same for all cases.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538943","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}

引用次数: 0

Tensile behaviour of a novel grouted sleeve splice for high-strength rebars 用于高强度钢筋的新型灌浆套筒接头的拉伸性能

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107631

{"title":"Tensile behaviour of a novel grouted sleeve splice for high-strength rebars","authors":"","doi":"10.1016/j.istruc.2024.107631","DOIUrl":"10.1016/j.istruc.2024.107631","url":null,"abstract":"<div><div>This study introduces a novel type of grouted sleeve fabricated from a standard low-alloy seamless steel pipe using cold-rolling techniques. The main goal is to achieve an effective connection between the high-strength steel (HSS) reinforcements in the joints of precast concrete structures. To investigate the structural performance of the developed splice under uniaxial tensile loading, 24 coupler specimens configured with 28 mm diameter HRB600 reinforcements were prepared. Two primary parameters, namely the embedded length of the spliced bar and number of inner concentric ribs rolled on the sleeve, were considered. By conducting direct pullout tests, the performance of the developed splices was thoroughly assessed based on the failure mode, bond stiffness, bond ductility, and strength. The test results demonstrated that increasing the bar embedded length and number of inner ribs enhances the initial bond stiffness and ductility of the splice. Increasing the quantity of inner ribs only in the inelastic region of the splice is effective for improving its tensile capacity. For grout splices with large-diameter HSS bars, an embedded length of 8<em>d</em><sub>b</sub> is recommended to guarantee bar fracture failure and satisfy the specification requirements. This length exceeds that of splices with normal-strength reinforcements. Finally, a formula was proposed to estimate the inelastic region length and tensile strength of the proposed splice.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538944","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}

引用次数: 0

Evaluation of the flexural stiffness of a lattice girder composite slab at the construction stage according to the lattice girder shape 根据格构梁形状评估施工阶段格构梁复合楼板的抗弯刚度

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107558

{"title":"Evaluation of the flexural stiffness of a lattice girder composite slab at the construction stage according to the lattice girder shape","authors":"","doi":"10.1016/j.istruc.2024.107558","DOIUrl":"10.1016/j.istruc.2024.107558","url":null,"abstract":"<div><div>Lattice girder composite slabs (LGCS) for use in construction stages are structures in which part of the lattice girder is embedded in precast concrete panels with a thickness of less than 100 mm. they serve as a permanent formwork supporting the casting loads of on-site concrete while constituting a portion of the RC slab. In this study, analytical research was conducted to evaluate the flexural stiffness of LGCS effectively and simply considering a range of variables. Based on the results, an Euler-Bernoulli beam-theory-based equivalent sectional analysis method is proposed. To achieve this, the study extracted the second moments of area (<span><math><msub><mrow><mi>I</mi></mrow><mrow><mi>exp</mi></mrow></msub></math></span>) from the experimental results of previous researchers and compared them with the second moments of area (<span><math><msub><mrow><mi>I</mi></mrow><mrow><mi>beam</mi></mrow></msub></math></span>) calculated using the Euler-Bernoulli beam-theory-based sectional analysis, analyzing how the ratio (<span><math><mrow><msub><mrow><mi>I</mi></mrow><mrow><mi>beam</mi></mrow></msub><mo>/</mo><msub><mrow><mi>I</mi></mrow><mrow><mi>exp</mi></mrow></msub></mrow></math></span>) varies according to the design parameters. Variable analyses over a wide range were conducted by expanding the types and ranges of variables, and the effects of different variables and ranges were analyzed by comparing the second moments of area based on an FE analysis of LGCS (<span><math><msub><mrow><mi>I</mi></mrow><mrow><mi>FEM</mi></mrow></msub></math></span>) with those based on a beam analysis (<span><math><msub><mrow><mi>I</mi></mrow><mrow><mi>beam</mi></mrow></msub></math></span>). Furthermore, to apply the equivalent sectional analysis method to LGCS, equivalent second-moment-of-area formulas were proposed through the equivalent neutral axis and equivalent arm length for each sectional element.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538978","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}

引用次数: 0

Combined tuned mass damper and vibro-impacting nonlinear energy sink for the seismic protection of frame structures 用于框架结构抗震保护的组合式调谐质量阻尼器和振动冲击非线性能量汇

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107576

{"title":"Combined tuned mass damper and vibro-impacting nonlinear energy sink for the seismic protection of frame structures","authors":"","doi":"10.1016/j.istruc.2024.107576","DOIUrl":"10.1016/j.istruc.2024.107576","url":null,"abstract":"<div><div>It is well established that, for tuned mass dampers, a high mass ratio relative to the protected structure is essential for effective performance under seismic excitation in most scenarios. This paper proposes a novel method to enhance the seismic effectiveness of a tuned mass damper without increasing the mass ratio. The proposed approach introduces an innovative device in which a tuned mass damper is serially coupled with a vibro-impacting mass that slides with negligible friction before impacting the boundaries of its runway. This system is then connected to the first storey of the frame structure via a Kelvin–Voigt visco-elastic device. The study employs a dynamically equivalent four-degree-of-freedom model, with its governing equations derived through a direct formulation approach. Initially, the coupled system is subjected to harmonic excitation, and the resulting behaviour is represented using frequency–response curves, which depict the maximum displacements of the structure in relation to the excitation frequency. Following this, a subsequent analysis involves subjecting the system to three distinct earthquake records to evaluate its performance under seismic excitation. To evaluate the effectiveness of the proposed protective device in reducing the displacements of the frame structure during seismic events, the displacements of the first storey and the drifts of the superstructure are compared to those of a frame structure without the external device. The findings indicate that the proposed device performs effectively across a wide range of system parameters, proving to be especially effective for low- and medium-rise frame structures.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539016","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}

引用次数: 0

Structural behaviour and design of wire arc additively manufactured bolted connections with thick plates 线弧加成型厚板螺栓连接的结构行为和设计

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107573

{"title":"Structural behaviour and design of wire arc additively manufactured bolted connections with thick plates","authors":"","doi":"10.1016/j.istruc.2024.107573","DOIUrl":"10.1016/j.istruc.2024.107573","url":null,"abstract":"<div><div>The application of additive manufacturing technology in the construction industry is currently a popular topic around the world. However, the research on the structural behaviour of thick plates produced via Wire and Arc Additive Manufacturing (WAAM) technology has been limited, despite the demand for such components in large-scale constructions that is subjected to large actions. This paper investigated the structural behaviour and design of WAAM single-shear bolted connections with thick plates with failure modes of net section, tilt-bearing, and end-splitting failure. The mechanical properties of the material were first determined by means of tensile coupon tests. An experimental programme of 32 sets of bolted connections with varying dimensions and print layer orientations was conducted. An anisotropic behaviour of WAAM steel bolted connections with different print layer orientations was observed, which had an influence on their failure modes and ultimate capacities. The experimental results were analysed and compared to the predictions using existing design approaches corresponding to conventional steel bolted connections. The comparison showed that these approaches were applicable to WAAM steel bolted connections, but there were still some limitations in the existing design guidelines. This research can contribute to the application of 3D printing technology in constructions.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bidirectional seismic fragility analysis of double-deck viaduct frame piers based on stripe-cloud method 基于条纹云法的双层高架桥框架墩双向地震脆性分析

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107597

{"title":"Bidirectional seismic fragility analysis of double-deck viaduct frame piers based on stripe-cloud method","authors":"","doi":"10.1016/j.istruc.2024.107597","DOIUrl":"10.1016/j.istruc.2024.107597","url":null,"abstract":"<div><div>To evaluate the influence of bidirectional seismic action on the seismic fragility of double-deck viaduct fram pier (DVFP), this study employs a vector-valued intensity measure (<em>IM</em>) [<em>PGA</em>, <em>Sa</em> (<em>T</em><sub>1</sub>, 5 %)], in tandem with the stripe-cloud method. The study compares the median values of <em>Sa</em> and the damage probability difference index (<em>DI</em>) to analyze the fragility of DVFP under both unidirectional and bidirectional seismic actions. Additionally, this research investigates the sensitivity of bidirectional seismic fragility of DVFP to the incidence angles. The results indicate a notable decrease in the median <em>Sa</em> values for DVFP are observed under bidirectional seismic action, with decreases of 28.6 %, 24.3 %, 20.9 %, and 18.8 % corresponding to four damage states, as compared to those under unidirectional seismic action, and the corresponding parameter <em>DIs</em> are measured at 0.122, 0.182, 0.245, and 0.291, respectively. Notably, the most severe damage to DVFP occurs when the bidirectional seismic incidence angle is within the range of 120–135°. At this angle, the median <em>Sa</em> values at four damage states are 85.8 %, 86.1 %, 87.6 %, and 88.6 %, respectively, compared to the angle of 0°. Therefore, neglecting the influence of bidirectional seismic incidence angles may lead to an underestimation of the bidirectional seismic fragility of DVFP.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539015","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}

引用次数: 0

Modified plastic stress distribution method incorporating size effect for strength prediction of CFST members 用于 CFST 构件强度预测的包含尺寸效应的修正塑性应力分布法

IF 3.9 2区工程技术

Structures Pub Date : 2024-10-24 DOI: 10.1016/j.istruc.2024.107632

{"title":"Modified plastic stress distribution method incorporating size effect for strength prediction of CFST members","authors":"","doi":"10.1016/j.istruc.2024.107632","DOIUrl":"10.1016/j.istruc.2024.107632","url":null,"abstract":"<div><div>Large-size concrete-filled steel tubular (CFST) members are widely applied in long-span and heavily-loaded structures due to increasing engineering demands. However, due to the size effect, applying the existing design methods to large-size CFST members may overestimate the load capacity, leading to unsafe designs. The plastic stress distribution (PSD) method is widely used as the primary method in typical design codes for calculating the strength of CFST members that are not susceptible to local buckling, while the PSD method was mainly used previously to evaluate the strength of CFST members with relatively small size. In this work, the experimental database of short CFST members with compact sections was complied, and the applicability of the PSD method was evaluated. The results showed that the test-to-calculated ratios decreased with increasing size of CFST members, and unsafe designs emerged for large-size CFST members. Based on the observations, the mechanics-based modified plastic stress distribution (MPSD) method was proposed, which not only considered the size effect at the material level similar to the way treated in most of the previous calculation methods, but also incorporated the size effect of the interaction action between the steel tube and concrete at the member level. Finally, the MPSD method was evaluated against the experimental database, and good agreement was achieved. These results provide strong justification for changes to the PSD method in design standards.</div></div>","PeriodicalId":48642,"journal":{"name":"Structures","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538732","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}

引用次数: 0