Journal of Constructional Steel Research最新文献_第10页

Scale-dependent strain rate sensitivity constitutive model and fracture damage prediction for DP600 DP600尺度相关应变率敏感性本构模型及断裂损伤预测

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-11 DOI: 10.1016/j.jcsr.2025.110168

Guoxi Jing , Jiahao Jia , Guang Chen , Xinyu Zheng , Yafei Fu , Pengsai Zhang

DP600, widely used in critical structural components like building steel beams due to its excellent seismic and impact resistance, requires accurate prediction of its plastic and fracture behavior under impact loading for building safety. This study integrates quasi-static/dynamic uniaxial tensile experiments with finite element analysis (FEA) under an uncoupled damage mechanics framework to characterize DP600's post-necking plastic deformation across strain rates and predict its sudden fracture. A strain rate-dependent weighted Ludwik-Voce (SLV) constitutive model is developed, which precisely calibrates post-necking true stress-plastic strain relationships, captures the distinct hardening mechanisms of martensite/ferrite, and reflects strain rate sensitivity. To reveal the correlation between fracture behavior and the evolution of stress state and strain path, a multi-dimensional analysis is conducted by employing the Rice–Tracey model to quantify the effect of stress triaxiality on microvoid evolution and the strain rate-dependent fracture forming limit diagram (SFFLD) to depict non-linear strain-path evolution in the major–minor plane strain space. This method achieves over 97 % agreement between FEA and experimental results for DP600's tensile fracture prediction under different strain rates. Additionally, correlation analysis between equivalent plastic strain (PEEQ) and damage variables quantitatively reveals the intrinsic relationship between damage accumulation and plastic strain development.

DP600由于具有优异的抗震和抗冲击性能，广泛应用于建筑钢梁等关键结构构件，为了建筑安全，需要准确预测其在冲击载荷下的塑性和断裂行为。本研究将准静态/动态单轴拉伸实验与非耦合损伤力学框架下的有限元分析（FEA）相结合，以表征DP600在不同应变速率下的颈后塑性变形，并预测其突然断裂。建立了应变速率相关的加权Ludwik-Voce （SLV）本构模型，该模型精确地校准了颈缩后的真应力-塑性应变关系，捕捉了马氏体/铁素体的不同硬化机制，并反映了应变速率敏感性。为了揭示断裂行为与应力状态和应变路径演化的相关性，采用Rice-Tracey模型进行了多维分析，量化了应力三轴性对微孔隙演化的影响，并采用应变率相关的断裂形成极限图（SFFLD）描述了主-小平面应变空间的非线性应变路径演化。该方法对不同应变速率下DP600的拉伸断裂预测结果与有限元分析结果的符合率达到97%以上。通过等效塑性应变（PEEQ）与损伤变量的相关性分析，定量揭示了损伤积累与塑性应变发展之间的内在联系。

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引用次数: 0

Fire performance of end-restrained circular steel tube confined reinforced concrete columns 端部约束圆形钢管约束钢筋混凝土柱的防火性能

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-11 DOI: 10.1016/j.jcsr.2025.110187

Bochi Duan , Dongdong Yang , Faqi Liu , Hua Yang , Yong Zhu

Structural fire safety is an essential concern in the design of steel tube confined reinforced concrete (STCRC) column, an innovative type of steel-concrete composite structural member. While extensive research has been conducted and design methods are available for the fire behaviour of circular STCRC columns with pinned conditions, the fire performance of these columns with end restraints, particularly considering varying end restraints with time increasing (hereafter referred to as time-dependent restraints), remains underexplored. This study, for the first time, investigates the fire performance of circular STCRC columns in non-sway frames with end restraints via finite element analysis (FEA). The investigation covers various scenarios, including axial and rotational restraints (individually and in combination), and constant and time-dependent conditions. The effects of axial restraint ratio, rotational restraint ratio, load ratio, cross-sectional diameter, and slenderness ratio on the fire resistance of end-restrained circular STCRC columns were examined. It was observed that an increase in restraint stiffness, whether axial or rotational, markedly enhances the column's fire resistance, with improvements reaching up to 830 %. Quantitative analyses were conducted to compare the fire behaviour of columns with time-dependent restraints resulting from the stiffness degradation of adjacent beams to those with constant restraints. The cumulative negative effect of time-dependent restraints on fire resistance is generally negligible. Based on existing methods for pin-ended STCRC columns, this study develops fire resistance design recommendations for end-restrained circular STCRC columns, accounting for the beneficial effects and time-dependent degradation of end restraints on the failure axial force and buckling length.

钢管约束钢筋混凝土柱是一种新型钢-混凝土组合构件，其结构防火安全是设计中必须考虑的问题。虽然已经进行了广泛的研究，并且设计方法可用于固定条件下的圆形STCRC柱的火灾行为，但这些具有端部约束的柱的火灾性能，特别是考虑到随着时间增加而变化的端部约束（以下称为时间相关约束），仍未得到充分探索。本研究首次通过有限元分析（FEA）研究了具有端部约束的非摇摆框架中圆形STCRC柱的防火性能。研究涵盖了各种情况，包括轴向和旋转约束（单独和组合），以及恒定和时间相关的条件。研究了轴向约束比、旋转约束比、荷载比、截面直径和长细比对端约束圆形STCRC柱耐火性能的影响。据观察，约束刚度的增加，无论是轴向还是旋转，显著提高了柱的耐火性能，提高幅度高达830%。定量分析进行了比较柱的火灾行为与时间相关的约束，导致相邻梁的刚度退化与那些恒定的约束。时间依赖性约束对耐火性能的累积负面影响通常可以忽略不计。基于现有的钉端STCRC柱的设计方法，本研究提出了端部约束圆形STCRC柱的耐火设计建议，考虑了端部约束对破坏轴力和屈曲长度的有益影响和随时间的退化。

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引用次数: 0

Corrigendum to Axial compression behaviours of UHPC-filled stainless steel tubes at cold-region low temperatures [Journal of Constructional Steel Research Volume 235, December 2025, 109813] 低温下uhpc填充不锈钢管轴向压缩性能的勘误表[j] . construction steel Research Volume 235, December 2025, 109813。

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-10 DOI: 10.1016/j.jcsr.2025.110194

Jia-Bao Yan , Yixuan Wang , Yunbiao Luo , Zirui Wang , Zhe Wang

引用次数: 0

Corrigendum to “Axial compression behaviors of aluminium tubular columns exposed to low-temperature environment” [Journal of Constructional Steel Research 235 (2025) 109784] “低温环境下铝管柱的轴向压缩性能”的勘误表[结构钢研究杂志235 (2025)109784]

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-10 DOI: 10.1016/j.jcsr.2025.110193

Jia-Bao Yan , Jin-Ping Zhao , Yu-Cai Zhao , Yun-Biao Luo , Ming Li

引用次数: 0

Beam–to–column joint solutions for reusable moment-resisting steel frames 可重复使用的抗弯矩钢框架的梁柱连接解决方案

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-09 DOI: 10.1016/j.jcsr.2025.110163

Isidora Jakovljević, Jelena Dobrić, Nina Gluhović, Milan Spremić

This paper advances reusable building practices by introducing an innovative beam–to–column joint for moment-resisting steel frames. The proposed joint, featuring T-stubs and cleats, is fully demountable, employing bolted connections instead of welds. Moreover, it is designed to accommodate reclaimed steel, incorporating an adaptable link that extends the service length of existing members and adjusts them to the required span of a new structure. Experimental testing was conducted on three test specimens to evaluate joint performance and identify failure modes, moment resistance, rotation capacity and stiffness. Two joint configurations were tested, varying the T-stub section and number of bolts on the T-stub web–to–beam flange connection. Additionally, the influence of material origin, reclaimed versus new steel, was investigated through two specimens with identical configurations. Testing revealed two failure modes: bearing deformation at bolt holes in the T-stub web and failure of the first bolt row on the column flange. Results also highlighted the critical role of bolt slip resistance on the T-stub web–to–beam flange connection in governing the rotational stiffness. Finite element models were developed and validated against the experimental results to simulate the mechanical behaviour of the joints. A parametric numerical study explored key design variables, including link length, bolt diameter, and number of bolts. The findings contributed to improving the joint structural performance by increasing its resistance and delaying the stiffness degradation. Results indicated that increasing the link length from 100 to 150 mm does not have a negative effect on the joint performance.

本文通过引入一种创新的抗弯矩钢框架的梁柱节点，提出了可重复使用的建筑实践。提议的接头，具有t型桩和cleats，是完全可拆卸的，采用螺栓连接而不是焊接。此外，它的设计是为了容纳再生钢，结合一个可适应的连接，延长现有成员的使用长度，并调整它们以适应新结构所需的跨度。对3个试件进行试验测试，评估节点性能，识别节点破坏模式、弯矩抗力、转动能力和刚度。测试了两种连接形式，分别改变了t形短段的截面和t形短段腹板到梁的法兰连接上的螺栓数量。此外，通过两个具有相同结构的试样，研究了材料来源（再生钢与新钢）的影响。试验发现了两种破坏模式：t形腹板螺栓孔的承载变形和柱翼缘第一排螺栓的破坏。结果还强调了螺栓抗滑移在t型短板-梁法兰连接中对控制旋转刚度的关键作用。建立了有限元模型，并根据实验结果进行了验证，以模拟节点的力学行为。参数化数值研究探讨了关键的设计变量，包括连杆长度、螺栓直径和螺栓数量。研究结果有助于提高节点的结构性能，增加节点的阻力，延缓节点的刚度退化。结果表明，将连接长度从100 mm增加到150 mm对连接性能没有负面影响。

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引用次数: 0

Equivalent elastic-plastic model of horizontally CSPSW used in structural design 水平CSPSW等效弹塑性模型在结构设计中的应用

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-09 DOI: 10.1016/j.jcsr.2025.110185

Bo-Li Zhu , Wen-Cong Liu , Hong-Wei Shan , Xiao-Dong Wang , Yan-Lin Guo

This paper studies the elastic-plastic performance of horizontally corrugated steel plate shear wall (HCSPSW) under shear force and proposes an elastic-plastic equivalent simplified calculation model for HCSPSW. Firstly, a refined finite element model of the HCSPSW is adopted for its elastic-plastic analysis to numerically obtain the shear performance skeleton curve that could reflect local and global buckling behaviors. Based on the refined FE numerical results from the shear load-displacement curves of the HCSPSW, the initial stiffness, ultimate shear-bearing stability coefficient φ and residual shear-bearing stability coefficient φ_r on the shear skeleton curves of HCSPSW are estimated and established according to varying regularized aspect ratio λ_n. In particular, key design parameters of the shear skeleton curves were predicted with continuously varying regularized aspect ratio λ_n. Subsequently an equivalent simplified calculation model of the HCSPSW for its elastic-plastic analysis and design was established based proximately on the same shear load displacement curve obtained from the refined FE model in estimating its elastic-plastic performance. Finally, by introducing a three-storey and three-span frame-HCSPSW structural model for push-over analysis, a comparison of the full-process push-over curves between the equivalent model and the refined FE model was carried out. It was demonstrated that the equivalent model can effectively predict the initial stiffness, ultimate shear-bearing capacity, and residual shear-bearing capacity of the HCSPSW. Therefore, as an equivalent elastic-plastic model for completing preliminary structural design of HCSPSWs embedded in frames, its shear skeleton curve could can be used directly.

研究了水平波纹钢板剪力墙在剪力作用下的弹塑性性能，提出了水平波纹钢板剪力墙弹塑性等效简化计算模型。首先，采用精细化有限元模型对其进行弹塑性分析，数值得到反映局部和全局屈曲行为的剪切性能骨架曲线；基于HCSPSW剪切荷载-位移曲线的精细化有限元计算结果，根据不同的正则化长径比λn，估计并建立了HCSPSW剪切骨架曲线上的初始刚度、极限剪切-承载稳定系数φ和残余剪切-承载稳定系数φr。特别地，用连续变化的正则化纵横比λn来预测剪切骨架曲线的关键设计参数。在此基础上，基于精化有限元模型得到的相同剪切载荷位移曲线，建立了等效简化计算模型，对其进行弹塑性分析和设计。最后，通过引入三层三跨框架- hcspsw结构模型进行推覆分析，对比了等效模型与精化有限元模型的全过程推覆曲线。结果表明，该等效模型能够有效地预测HCSPSW的初始刚度、极限剪切承载力和剩余剪切承载力。因此，其剪力骨架曲线可直接作为框架内嵌式混凝土梁的等效弹塑性模型来完成结构初步设计。

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引用次数: 0

Ultra-low-cycle-fatigue prediction of LY225 steel using an improved Lode parameter enhanced cyclic-void-growth-model 基于改进Lode参数增强循环-空洞-生长模型的LY225钢超低周疲劳预测

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-09 DOI: 10.1016/j.jcsr.2025.110165

Xuewei Huang, Yihao Shen, Zeru Liu, Jun Zhao, Xu Zhang

This study conducted monotonic tensile and ultra-low-cycle-fatigue tests on LY225 low-yield strength steel under different stress states. Experimental results show that ultra-low cyclic loading yields a higher ultimate load than monotonic tension. The steel exhibits obvious cyclic hardening behavior, which becomes more pronounced with increasing strain amplitude. The notched plate specimens exhibit ductile dimple features under ultra-low cyclic loading. The Lode parameter enhanced cyclic void growth model (LCVGM) was employed to analyze the fracture behavior of the specimens. The model accurately reproduces the fracture response of LY225 steel specimens subjected to monotonic tension, however, it fails to accurately predict the ultra-low-cycle-fatigue life under constant-amplitude symmetric loading. To address this limitation, an improved Lode parameter enhanced cyclic void growth model (ILCVGM) was developed by modifying the damage evolution law in the LCVGM, which could better capture damage evolution under large compressive strains. The ILCVGM parameters were calibrated using ultra-low-cycle-fatigue test data of LY225 steel, followed by a comparative analysis of void evolution mechanisms in the ILCVGM and LCVGM. The ILCVGM was applied to simulate ultra-low-cycle-fatigue failure of LY225 steel notched plate specimens under different loading protocols. The predicted fatigue life closely matches the experimental data, validating the effectiveness of the ILCVGM in predicting and analyzing ultra-low-cycle-fatigue fracture.

对LY225低屈服强度钢在不同应力状态下进行了单调拉伸和超低周疲劳试验。试验结果表明，超低循环加载比单调拉伸产生更高的极限荷载。钢表现出明显的循环硬化行为，随应变幅值的增加循环硬化行为更加明显。缺口板试样在超低循环荷载作用下表现出延性韧窝特征。采用Lode参数增强循环空隙生长模型（LCVGM）对试件的断裂行为进行分析。该模型能较准确地再现LY225钢试件在单调拉伸作用下的断裂响应，但不能准确预测等幅对称加载下的超低周疲劳寿命。针对这一缺陷，通过修改Lode参数增强循环空洞增长模型（ILCVGM）中的损伤演化规律，建立了改进的Lode参数增强循环空洞增长模型（ILCVGM），该模型能够更好地捕捉大压缩应变下的损伤演化。利用LY225钢的超低周疲劳试验数据对ILCVGM参数进行了标定，并对比分析了ILCVGM和LCVGM的空洞演化机制。采用ILCVGM模拟了不同加载方案下LY225钢缺口板试件的超低周疲劳破坏。预测疲劳寿命与实验数据吻合较好，验证了ILCVGM在超低周疲劳断裂预测分析中的有效性。

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引用次数: 0

Axial compression behavior of corner-stiffened concrete-filled double-skin steel tubular (CFDST) members: Experimental and analytical research 角加筋双层钢管混凝土（CFDST）构件轴压性能：试验与分析研究

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-08 DOI: 10.1016/j.jcsr.2025.110164

Jian-Tao Wang, Kai-Lin Yang, Yang Yang, Zu-Qiang Liu, Juan Wang

Traditional square concrete-filled double-skin steel tubular (CFDST) member inevitably has the limitation of stress concentration at the steel tube corners, making it difficult to meet the development needs of heavy-load structures. This paper proposed a new-type corner-stiffened CFDST members for the potential application in the towers or piers of long-span bridges. An axial compression test was conduct to investigate its compressive behavior, where the failure mode involved the inward buckling of inner steel tube, outward buckling of flat steel plate and corner steel tube, and the concrete crushing. A finite element (FE) model was verified in terms of the failure mode, full-range load-displacement curve and maximum bearing capacity, for the further mechanism analysis and parametric study. Mechanism investigation reflects that: the reinforcement of corner concrete-filled steel tubular (CFST) members intensifies the confining stress between the corner concrete and corner steel tube within the reinforced zone; the flat steel plate and inner steel tube function independently, without generating substantial confining stress. Parametric study on material-geometric parameters reveals that: inner steel tube strength (f_yi) has a slight effect on the compressive capacity, e.g., the bearing capacity respectively improves by 1.85 % and 2.98 % as f_yi increases from 355 MPa to 460 MPa and 550 MPa; inner steel tube strength, diameter-to-thickness ratio of inner steel tube, and hollow ratio slightly affect the confining stress of the corner CFST component. Finally, the calculation method was established and validated for predicting the compressive capacity of corner-stiffened CFDST members.

传统的方形双皮钢管混凝土（CFDST）构件不可避免地存在应力集中在钢管角部的局限性，难以满足大荷载结构发展的需要。本文提出了一种新型角加劲CFDST构件，具有应用于大跨度桥梁塔架或桥墩的潜力。通过轴压试验研究其抗压特性，破坏模式为内钢管向内屈曲，扁钢板和角钢管向外屈曲，混凝土破碎。从破坏模式、全范围载荷-位移曲线和最大承载能力等方面对有限元模型进行了验证，为进一步的机理分析和参数化研究奠定了基础。机理研究表明：角部钢管混凝土（CFST）构件的加固加剧了钢筋区域内角部混凝土与角部钢管之间的围应力；扁钢板与内钢管独立工作，不产生较大的围应力。材料几何参数的参数化研究表明：钢管内强度（fyi）对抗压能力影响较小，当fyi从355 MPa增加到460 MPa和550 MPa时，承载力分别提高1.85%和2.98%；内钢管强度、内钢管径厚比和空心比对拐角CFST构件的围应力影响较小。最后，建立了角加筋CFDST构件抗压能力预测的计算方法，并进行了验证。

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引用次数: 0

Behaviour of plywood-sheathed cold-formed steel shear walls under monotonic and cyclic in-plane shear loading 单调和循环面内剪切荷载作用下胶合板冷弯型钢剪力墙的性能

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-08 DOI: 10.1016/j.jcsr.2025.110172

Karmugilan Selvakumari Panchamoorthy, Mahendrakumar Mathialagu Madhavan

A total of sixteen full scale cold-formed steel (CFS) shear wall panels sheathed with plywood were tested to investigate the seismic performance under monotonic and cyclic loading conditions. The primary objective is to study the influence of sheathing thickness and screw spacing on the wall's initial stiffness, shear strength, ductility, stiffness degradation and energy dissipation capacity. A 3-dimensional Digital Image Correlation (DIC) was employed to study the full field behaviour of CFS shear wall and to obtain in-plane deformation and strain distribution under various stages of loading. The failure modes, including tilting, bearing, pull-through, and screw shear failure were observed, depending on sheathing thickness and screw spacing. Reducing screw spacing from 150 mm to 100 mm enhanced the average yield strength by up to 30 %, while increasing sheathing thickness from 9 mm to 12 mm improved the initial stiffness and ultimate strength, providing greater resistance to shear deformation. The experimental-to-code strength ratios ranged between 1.15 and 1.35, confirming the conservatism of current AISI S400–20 provisions. Although thicker sheathing contributed to higher stiffness, the overall in-plane shear resistance was still governed by the screw-to-sheathing connection, as confirmed through detailed observations and Digital Image Correlation (DIC) analysis. These findings validate the capacity-based design principle, wherein the sheathing-to-frame connection acts as the primary ductile mechanism while maintaining frame integrity. The present study addresses limitations in shear strength estimation in AISI S400–20, particularly for double-sided sheathed CFS walls with 2 mm thick framing configurations not explicitly covered in current standards. The findings provide insight into the influence of framing thickness, fastener layout, and sheathing properties on wall performance, and suggest essential considerations for refining design approaches and guiding future experimental research in CFS construction systems.

对16块冷弯型钢（CFS）剪力墙板在单调和循环荷载作用下的抗震性能进行了试验研究。主要目的是研究护套厚度和螺杆间距对墙体初始刚度、抗剪强度、延性、刚度退化和耗能能力的影响。采用三维数字图像相关技术（DIC）研究了CFS剪力墙的全场特性，得到了不同加载阶段下CFS剪力墙的面内变形和应变分布。根据护套厚度和螺杆间距的不同，观察到的破坏模式包括倾斜、承载、拉穿和螺杆剪切破坏。将螺杆间距从150毫米减少到100毫米，平均屈服强度提高了30%，而将护套厚度从9毫米增加到12毫米，提高了初始刚度和极限强度，提供了更大的抗剪切变形能力。实验与规范强度比在1.15 - 1.35之间，证实了现行AISI S400-20规定的保守性。虽然更厚的护套有助于提高刚度，但通过详细观察和数字图像相关（DIC）分析证实，整体面内剪切阻力仍然受螺纹与护套连接的控制。这些发现验证了基于能力的设计原则，其中，在保持框架完整性的同时，护套与框架的连接是主要的延性机制。本研究解决了AISI S400-20中抗剪强度估计的局限性，特别是对于目前标准中未明确涵盖的2毫米厚框架结构的双面护套CFS墙。这些发现为框架厚度、紧固件布局和护套性能对墙体性能的影响提供了见解，并为改进设计方法和指导未来CFS结构系统的实验研究提出了必要的考虑因素。

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引用次数: 0

Load-carrying mechanism of TOBs bolted steel beam to CFST column joints TOBs螺栓连接钢梁与钢管混凝土柱节点的承载机理

IF 4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of Constructional Steel Research

Pub Date : 2025-12-08 DOI: 10.1016/j.jcsr.2025.110150

Min Cai , Houming Yang , Le Liu , Peijun Wang , Youkun Sun

The load-carrying mechanism of Thread-fixed One-side Bolts (TOBs) bolted steel beam to Concrete-Filled Steel Tubular (CFST) column joints is rather complex due to the unique anchorage method of TOBs and the interaction between different components. Since this mechanism is challenging to observe directly through experiments, an advanced FE model was developed in this paper to numerically investigate the load-carrying mechanism of TOBs bolted steel beam to CFST column joints, including the failure of hole threads, coordination working between stiffener and column wall, contact pressure on endplate, and stress distribution of core concrete. In addition, a comprehensive parametric analysis was conducted on several parameters, such as installation gaps, concrete strength, stiffener type, and so on. Parametric studies encompassing 29 joint configurations revealed that: 1) Bolt diameter and endplate thickness critically influenced the load-carrying capacity of joints, with improvement by 24.9 % when increasing bolt diameter from M16 to M20 and by 17.35 % when changing endplate thickness from 14 mm to 20 mm; 2) H-shaped stiffener, P-stiffener with vertical rib or transverse rib demonstrated more uniform stress diffusion than polygonal counterpart through enhanced force transmission paths; 3) Spiral wire inserts can restore original capacity in thread-repaired joints by improving load distribution uniformity. Furthermore, the theoretical results and FEM values of yield bending moment for connections were well-matched, with errors no greater than 15 %.

螺纹固定单边螺栓（TOBs）连接钢管混凝土柱节点的钢梁，由于其独特的锚固方式和不同构件之间的相互作用，其受力机理较为复杂。由于这种机理难以通过实验直接观察，本文建立了一种先进的有限元模型，对TOBs螺栓钢梁与CFST柱节点的承载机理进行了数值研究，包括孔螺纹破坏、加强筋与柱壁协同工作、端板接触压力以及核心混凝土的应力分布。此外，还对安装间隙、混凝土强度、加劲筋类型等参数进行了全面的参数分析。包含29种节点配置的参数化研究表明：1)螺栓直径和端板厚度严重影响节点的承载能力，当螺栓直径从M16增加到M20时，提高了24.9%，当端板厚度从14 mm增加到20 mm时，提高了17.35%；2) h型加劲肋、竖肋p型加劲肋和横肋p型加劲肋通过增强的力传递路径，表现出比多边形加劲肋更均匀的应力扩散；3)螺旋插丝可以通过提高载荷分布均匀性来恢复螺纹修复接头的原有能力。节点屈服弯矩的理论计算结果与有限元计算结果吻合较好，误差不大于15%。

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引用次数: 0