Journal of Constructional Steel Research最新文献

Seismic time history response prediction of modular buildings using transformer-based machine learning models 基于变压器的机器学习模型的模块化建筑地震时程响应预测

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

Journal of Constructional Steel Research

Pub Date : 2026-01-31 DOI: 10.1016/j.jcsr.2026.110256

Peifeng Tian , Chen Wang , Tak-Ming Chan , Ahmed Y. Elghazouli

Despite the rapid development and application of modular buildings, the structural behaviour of high-rise configurations requires further detailed investigations. In order to enable extensive studies into the nonlinear seismic time history response of such large and complex buildings, there is a need to develop computationally efficient approaches. This investigation therefore, describes the development of a machine-learning approach for predicting the time history response of modular buildings using a transformer model architecture, which is found to be particularly suitable for such sequence-to-sequence tasks. The proposed machine learning model is trained using a large database comprising the seismic time history response of a prototype high-rise modular building configuration through nonlinear time history analysis under a suite of 3000 ground motions. A special designed encoding function was applied to reflect the unique structural characteristics of modular buildings, while convolutional neural networks are used to capture both global and local features of seismic vibrations, followed by feature concatenation for the machine learning prediction. The proposed model is shown to provide a highly efficient prediction procedure that captures the time history response of such buildings. Finally, to demonstrate the applicability and effectiveness of the developed machine learning model, an illustrative example is presented in which the influence of inter-module connection properties on the seismic response of modular buildings is examined and discussed. Compared to widely used nonlinear finite element procedures, the proposed machine modelling methodology offers a fundamental approach for modular buildings to enable efficient large scale structural evaluations.

尽管模块化建筑的快速发展和应用，高层配置的结构行为需要进一步的详细研究。为了对此类大型复杂建筑的非线性地震时程反应进行广泛的研究，需要开发计算效率高的方法。因此，本研究描述了一种机器学习方法的发展，该方法用于使用变压器模型体系结构预测模块化建筑的时程响应，该方法被发现特别适合于这种序列到序列的任务。所提出的机器学习模型是使用一个大型数据库来训练的，该数据库包括一个原型高层模块化建筑配置的地震时程响应，通过对3000次地面运动的非线性时程分析。采用特殊设计的编码函数来反映模块化建筑的独特结构特征，而卷积神经网络用于捕获地震振动的全局和局部特征，然后进行特征拼接以进行机器学习预测。所提出的模型提供了一种高效的预测程序，可以捕获此类建筑物的时程响应。最后，为了证明所开发的机器学习模型的适用性和有效性，给出了一个说明性的例子，其中检查和讨论了模块间连接特性对模块化建筑地震反应的影响。与广泛使用的非线性有限元程序相比，提出的机器建模方法为模块化建筑提供了一种基本方法，以实现高效的大规模结构评估。

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引用次数: 0

Responses of partially-encased composite structural members subjected to lateral impact load: Experimental and analytical study 侧向冲击荷载作用下部分封闭复合材料构件的响应：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 : 2026-01-30 DOI: 10.1016/j.jcsr.2026.110261

Xipeng Ma , Yonghui Wang , Ximei Zhai , Hong Zhang , Hongyuan Zhou

The lateral impact responses of partially-encased composite (PEC) members were investigated via both experimental and analytical approaches. The impact experiments were conducted on PEC members to obtain their deformation process, failure mode, impact force–time and displacement–time responses. The effects of the initial velocity, clear span, impact direction and types of transverse reinforcements (i.e., links and stirrup) on impact responses of PEC members were experimentally investigated. The results indicated that the higher impact velocity would result in higher impact force, larger specimen deformation and energy dissipation. The PEC member with larger span exhibited smaller impact resistance, inducing larger specimen deformation. The impact direction had significant influence on the impact response of PEC members due to the differences in bending resistance. While the types of the transverse reinforcements employed in this study had negligible effect on the impact behaviours. Moreover, a two degrees-of-freedom (2-DOFs) model was developed to calculate the responses of the PEC members under the lateral impact. The developed 2-DOFs model demonstrated its applicability by accurately predicting the test results.

采用实验和分析两种方法研究了部分封装复合材料（PEC）构件的横向冲击响应。对PEC构件进行了冲击试验，得到了构件的变形过程、破坏模式、冲击力-时间和位移-时间响应。实验研究了初始速度、净跨、冲击方向和横向增强（即连接和箍筋）类型对PEC构件冲击响应的影响。结果表明：冲击速度越大，冲击力越大，试件变形越大，能量耗散越大；大跨度PEC构件的抗冲击能力较小，试件变形较大。由于弯曲抗力的差异，冲击方向对PEC构件的冲击响应有显著影响。而在本研究中采用的横向增强类型对冲击行为的影响可以忽略不计。此外，还建立了一个两自由度模型来计算PEC构件在横向冲击下的响应。通过对试验结果的准确预测，证明了该模型的适用性。

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引用次数: 0

Seismic performance of a novel prestressed high-performance exposed CFST column base 一种新型预应力高性能暴露钢管混凝土柱基础的抗震性能研究

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

Journal of Constructional Steel Research

Pub Date : 2026-01-29 DOI: 10.1016/j.jcsr.2026.110265

Zhou-Peng Cai , Ji-Ping Hao , Xiao-Ling Sun , Qiang Xue , Jing-Hua Wang

A novel prestressed high-performance exposed column base (NECB) for concrete-filled steel tubular (CFST) columns is proposed, incorporating an innovative steel shoe beam configuration and high-strength prestressed anchor bolts (HPABs). The seismic performance of the NECB was evaluated through quasi-static cyclic tests and finite element (FE) simulations. Three half-scale specimens were examined to characterize failure mechanisms, hysteretic response, stiffness and strength degradation, and energy dissipation capacity. Experimental results show that the NECB consistently achieves superior load-bearing capacity, stiffness, deformation capacity, and energy dissipation compared with a conventional concrete-encased column base (CECB). Validated FE models were subsequently established to perform parametric studies investigating the effects of axial load ratio, steel shoe beam parameters, and HPAB prestressing levels on seismic behavior. The FE analyses reveal that increased axial load, greater stiffener thickness, and the application of anchor-bolt prestress all enhance the initial stiffness and energy dissipation capacity of the column base, with anchor-bolt prestressing providing the most significant improvement.

提出了一种新型的预应力高性能钢管混凝土（CFST）柱暴露柱基础（NECB），结合了创新的钢鞋梁结构和高强度预应力锚杆（hpab）。通过准静力循环试验和有限元模拟对NECB的抗震性能进行了评价。测试了三个半尺度试件的破坏机制、滞后响应、刚度和强度退化以及能量耗散能力。试验结果表明，与传统的混凝土包壳柱基础（CECB）相比，NECB在承载能力、刚度、变形能力和耗能方面始终具有优越的性能。随后建立了验证的有限元模型，进行参数化研究，研究轴向载荷比、钢鞋梁参数和HPAB预应力水平对地震行为的影响。有限元分析结果表明，增加轴向荷载、加大加劲筋厚度和施加锚杆预应力均能提高柱基础的初始刚度和耗能能力，其中锚杆预应力对柱基础的改善作用最为显著。

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引用次数: 0

Hysteretic behavior of a tandem self-centering double-stage yielding buckling-restrained brace 串联自定心双级屈服屈曲约束支撑的滞回特性

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

Journal of Constructional Steel Research

Pub Date : 2026-01-29 DOI: 10.1016/j.jcsr.2026.110254

Yongkang Kang , Bo Wen , Shuaishuai Ji , Alessio Fumagalli , Zhengyao Yu , Wen Xia

This paper proposes a tandem self-centering double-stage yielding buckling-restrained brace (TSCDY-BRB). A staged-stiffness restoring-force model and a three-dimensional finite element model are developed and validated against quasi-static tests, and reproduce the hysteretic response within about 15% error. The brace exhibits stable flag-shaped hysteresis, transitioning from a single-flag loop at small drifts to a flag with a second yielding plateau after the Group-2 cores engage. Parametric studies indicate that prestress sets the strength baseline and controls recentering; strand diameter influences post-activation stiffness; the Group-1 core area dictates initial strength, stiffness and low-amplitude energy dissipation; the Group-2 core area governs Stage II strength, stiffness and high-amplitude dissipation; and a larger preset gap delays Stage II activation, improving recentering but reducing damping. Within the studied range, single-cycle energy dissipation reaches 6.5–10.5 kJ, with an equivalent viscous damping ratio of 0.12–0.17, and the residual-to-peak displacement ratio remains below 3% with suitable prestress and gap. For design, an initial prestress about 1.5 times the combined yield force of the two core groups is recommended, and the preset engagement gap and the yield displacement of the Group-2 cores should be coordinated with the target peak displacement to ensure effective recentering and staged energy dissipation. System-level analysis of a six-story steel frame shows that, compared with a double-stage yielding BRB frame of identical initial properties, the TSCDY-BRB frame achieves much smaller residual drifts while maintaining comparable peak drifts under 0.2 g and 0.4 g excitations, confirming its effectiveness over different seismic levels.

提出了一种串联自定心双级屈曲约束支撑（TSCDY-BRB）。建立了阶段刚度恢复力模型和三维有限元模型，并在准静态试验中进行了验证，在15%左右的误差范围内再现了滞回响应。支撑显示出稳定的旗形滞后，在小漂移时从单旗环过渡到第二次屈服平台后的旗环。参数研究表明，预应力设置了强度基线并控制了再入；股链直径影响活化后刚度；组-1核心区决定了初始强度、刚度和低幅值耗能；第二组核心区支配第二阶段强度、刚度和高振幅耗散；更大的预设间隙延迟Stage II激活，改善了重新进入，但降低了阻尼。在研究范围内，单周期能量耗散达到6.5 ~ 10.5 kJ，等效粘性阻尼比为0.12 ~ 0.17，在适当的预应力和间隙下，残峰位移比保持在3%以下。设计时，建议初始预应力为两核心组屈服力总和的1.5倍左右，且2组核心组的预设啮合间隙和屈服位移应与目标峰值位移协调，以保证有效的再入和阶段耗能。对六层钢框架的系统级分析表明，与具有相同初始性能的双级屈服BRB框架相比，TSCDY-BRB框架在0.2 g和0.4 g激励下保持相当的峰值漂移，同时获得了更小的残余漂移，证实了其在不同地震级别上的有效性。

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引用次数: 0

Impact of vertical pipe splicing on the stability of disk-buckle scaffolding 垂直管道拼接对盘扣式脚手架稳定性的影响

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

Journal of Constructional Steel Research

Pub Date : 2026-01-22 DOI: 10.1016/j.jcsr.2026.110252

Renzhang Yan , Haoping Ji , Shuai Wang , Penggang Zhu , Kai Peng , Changlong Zhang

Based on the steel pipe scaffold vertical pipes commonly used in engineering, this study established vertical pipe models under different splicing conditions. Adopting a combined method of theoretical derivation, numerical simulation, and experimental research, it conducted research on the influence law of vertical pipe splicing on its stability. Firstly, a calculation method for the stability of variable-section vertical pipes considering joint semi-rigidity was proposed through theoretical derivation. Subsequently, axial compression tests were carried out on vertical pipes with different splicing configurations, and combined with finite element simulation, the influence law of splicing positions on the ultimate bearing capacity and instability failure mode of vertical pipes was revealed. The research results show that: splicing of vertical pipes significantly enhances their ultimate bearing capacity, and the enhancement degree is closely related to the splicing position, with a maximum enhancement of 33.75%; additionally, the failure position of vertical pipes changes with different splicing conditions. Finally, a practical calculation method considering joint semi-rigidity and arbitrary position splicing was established through experimental correction.

本研究以工程中常用的钢管脚手架垂直管为研究对象，建立了不同拼接条件下的垂直管模型。采用理论推导、数值模拟和实验研究相结合的方法，研究了垂直管接对其稳定性的影响规律。首先，通过理论推导，提出了考虑接头半刚性的变截面垂直管道稳定性计算方法。随后，对不同拼接方式的垂直管道进行轴压试验，并结合有限元模拟，揭示了拼接位置对垂直管道极限承载力和失稳破坏模式的影响规律。研究结果表明：垂直管道的剪接显著提高了其极限承载力，且剪接位置与剪接增强程度密切相关，最大剪接增强幅度为33.75%；此外，不同的拼接条件下，垂直管道的破坏位置也会发生变化。最后，通过实验修正，建立了考虑节点半刚性和任意位置拼接的实用计算方法。

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引用次数: 0

Study on the global stability of members strengthened with outer sleeves 外套管加固构件整体稳定性研究

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

Journal of Constructional Steel Research

Pub Date : 2026-01-21 DOI: 10.1016/j.jcsr.2026.110250

Zeyuan Jin , Yunbo Yang , Jinghai Yu , Bin Wang , Shuangqiu Cao , Zhongwei Zhao

This paper presents a prefabricated outer-sleeve strengthening method to address buckling of compression members in space structures. Eleven axial compression specimens and accompanying numerical analyses investigate the influence of key parameters on global stability. Results show that sleeve reinforcement significantly increases the ultimate bearing capacity, and failure modes are dominated by buckling at the middle span and sleeve slippage. It is revealed that rational hoop spacing is critical for preventing capacity degradation, and an optimal configuration is identified to ensure effective composite action. Finite-element analyses indicate that increasing geometric dimensions such as sleeve thickness and outer diameter effectively enhances the capacity through increased moment of inertia. Furthermore, the sensitivity of the strengthened members to initial imperfections is quantified. Theoretical derivations demonstrate that the lateral restraint provided by the sleeve significantly reduces the equivalent slenderness ratio, confirming that lateral restraint governs stability improvement. Based on the small-deflection theory and static equilibrium conditions, the prediction formula for the ultimate capacity of sleeved reinforced members is derived. Verification results demonstrate good agreement between the theoretical predicted values and experimental values. The findings offer a theoretical basis for engineering practice.

针对空间结构中受压构件的屈曲问题，提出了一种预制外套筒加固方法。11个轴压试件及相应的数值分析研究了关键参数对整体稳定性的影响。结果表明：套筒加固显著提高了极限承载力，破坏模式以跨中屈曲和套筒滑移为主；研究表明，合理的环箍间距是防止能力退化的关键，并确定了最佳配置，以确保有效的复合作用。有限元分析表明，增大轴套厚度和外径等几何尺寸可通过增加转动惯量有效提高承载能力。此外，还量化了加固构件对初始缺陷的敏感性。理论推导表明，套筒的侧向约束显著降低了等效长细比，证实了侧向约束对稳定性提高的影响。基于小挠度理论和静力平衡条件，推导出套式加筋构件极限承载力的预测公式。验证结果表明，理论预测值与实验值吻合较好。研究结果为工程实践提供了理论依据。

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引用次数: 0

Axial behavior of RBA concrete column confined with lipped cold-formed steel box 唇形冷弯钢箱约束下RBA混凝土柱的轴向性能

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

Journal of Constructional Steel Research

Pub Date : 2026-01-21 DOI: 10.1016/j.jcsr.2026.110248

Pranoy Roy , Amiya K. Samanta

The rapid industrial and infrastructural growth throughout the globe generates a huge amount of Construction and Demolition (C&D) waste annually, which is mostly dumped and, as a result, degrades the environment largely. Recycled Brick Aggregate (RBA), which is mainly available from demolition of old masonry structures, can be processed as C&D waste, but it is primarily used for non-structural purposes due to its low strength and high water absorption capacity. On the other hand, cold formed steel is also used for non-structural applications due to its susceptibility to local buckling; however, it has proven its efficiency in providing passive confinement to concrete through enhanced load-carrying capacity and improved ductility. This study proposes a sustainable solution by considering a composite system of RBA concrete stub columns confined with thin-walled cold-formed steel, utilizing waste RBA to develop an effective structural solution for low-cost housing. In the present investigation, an experimental and numerical study on the axial compressive behaviour of seventy-five short columns has been conducted, where Natural Coarse Aggregate (NCA) was replaced with RBA in variable percentages of 0, 30, 50, 70 and 100, considering M30 grade concrete. The samples were divided into unconfined and confined samples with 1mm and 1.5mm thick cold formed lipped box sections of height 300mm and 500mm, respectively. Experimental results show improved performance in samples up to 30% replacement of NCA with RBA. The experimental peak loads were compared with existing codal stipulations and Finite Element Models (FEM). Based on the experimental data and findings, a Response Surface Methodology (RSM) based predictive equation is proposed for calculating the peak load applicable to similar configurations.

全球工业和基础设施的快速发展每年产生大量的建筑和拆除（C&；D）废物，这些废物大多被倾倒，因此在很大程度上恶化了环境。再生砖骨料（RBA）主要来自旧砌体结构的拆除，可以作为C&；D废物处理，但由于其强度低，吸水能力高，主要用于非结构用途。另一方面，冷弯型钢由于其易发生局部屈曲，也被用于非结构应用；然而，通过增强混凝土的承载能力和改善延性，它已经证明了它在为混凝土提供被动约束方面的效率。本研究提出了一种可持续的解决方案，通过考虑使用薄壁冷弯型钢约束的RBA混凝土短柱复合系统，利用废弃的RBA开发一种有效的低成本住房结构解决方案。在目前的调查中，对75根短柱的轴压行为进行了实验和数值研究，其中天然粗骨料（NCA）以0、30、50、70和100的不同百分比替换为RBA，考虑到M30级混凝土。试样分为无侧限和侧限试样，分别采用厚度为1mm和1.5mm、高度为300mm和500mm的冷弯唇形盒截面。实验结果表明，RBA替代NCA后，样品的性能提高了30%。将试验峰值荷载与现有规范和有限元模型进行了比较。基于实验数据和研究结果，提出了一种基于响应面法（RSM）的预测方程，适用于类似配置的峰值负荷计算。

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引用次数: 0

Numerical investigation of extremely low-cycle fatigue behavior in cylindrical steel specimens 圆柱钢试件极低周疲劳行为的数值研究

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

Journal of Constructional Steel Research

Pub Date : 2026-01-19 DOI: 10.1016/j.jcsr.2026.110247

Yoshiharu Sato , Suguru Itabashi , Yu Jiao , Satoshi Yamada

In extremely low-cycle fatigue (ELCF) tests using cylindrical specimens, localized necking deformation occurs, resulting in a non-uniform stress and strain state in the gauge section. Consequently, fatigue life is affected by gauge length. This effect impacts not only the fracture life but also the fatigue life up to the onset of strength degradation, which can be defined as the damage-initiation fatigue life. In this study, finite element analysis (FEA) was employed to examine the stress and strain state within a cylindrical specimen under ELCF conditions and investigate the influence of gauge length on the damage-initiation fatigue life. FEA was conducted based on two existing ELCF test methods using 490 N/mm² grade steel with different gauge lengths and strain amplitudes ranging from 3% to 12%. Two material constitutive models capable of accurately reproducing the stress–strain behavior under constant-strain-amplitude cyclic loading were employed. At the specimen center—where the fracture initiates under ELCF conditions—the mean strain shifted toward the tensile side as the number of cycles increased and the strain amplitude exceeded the controlled strain amplitude measured between the gauge points. Furthermore, the shift in mean strain and the increase in strain amplitude were more pronounced in specimens with longer gauge lengths. The influence of gauge length on fatigue life can generally be assessed by evaluating the damage-initiation fatigue life using the rain-flow counting method and Miner's linear cumulative damage rule applied to the strain history at the specimen center.

在使用圆柱形试样的极低周疲劳（ELCF）试验中，会发生局部颈缩变形，导致规范截面的应力和应变状态不均匀。因此，疲劳寿命受量规长度的影响。这种效应不仅影响断裂寿命，而且影响强度退化开始前的疲劳寿命，可定义为损伤起裂疲劳寿命。本研究采用有限元分析方法对ELCF条件下圆柱形试样的应力应变状态进行了研究，探讨了规长对损伤起裂疲劳寿命的影响。基于现有的两种ELCF试验方法，采用490n /mm2级钢，在应变幅值为3% ~ 12%的情况下，采用不同的应变长度和应变幅值进行有限元分析。采用了两种材料本构模型，能够准确再现等应变幅值循环加载下的应力-应变行为。在试样中心（ELCF条件下断裂开始的地方），随着循环次数的增加，平均应变向拉伸侧移动，应变幅值超过了测量点之间的控制应变幅值。此外，应变的平均位移和应变幅度的增加在较长的试件中更为明显。试件长度对疲劳寿命的影响一般可以通过采用雨流计数法和Miner线性累积损伤规则对试件中心应变历史进行损伤起爆疲劳寿命评估来评估。

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引用次数: 0

Seismic optimization design of Fe-SMA shear-friction hybrid dampers Fe-SMA剪切-摩擦混合阻尼器抗震优化设计

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

Journal of Constructional Steel Research

Pub Date : 2026-01-19 DOI: 10.1016/j.jcsr.2026.110253

Yunyun Zhu , Guanfan Chen , Jianrong Pan , Tulong Yin , Dian Wang

This study aims to enhance the seismic resilience of semi-rigid steel frames and to promote engineering applications through the optimized spatial deployment of a novel iron-based shape memory alloy shear-friction hybrid damper (FSMA-SFHD). The proposed FSMA-SFHD combines Fe-SMA shear plates with a friction unit, integrating the excellent low-cycle fatigue resistance of Fe-SMA with the rapid response of the friction unit under small-amplitude vibrations, thereby enabling efficient energy dissipation over the entire seismic cycle. To accurately simulate its mechanical behavior, a finite element model of the FSMA-SFHD was established based on the OpenSees platform, and its validity was verified through comparative mechanical performance tests. A multi-objective performance index that jointly considers inter-story drift ratio, floor acceleration, and roof displacement was formulated, and an elitist-preserving genetic algorithm was employed to optimize damper locations under a fixed damper quantity. Case studies on three-bay ten-story and four-bay eight-story frames show that the optimized layouts outperform random configurations: the optimized results demonstrate that, compared to random damper arrangements, the proposed scheme significantly enhances the peak displacement reduction ratio and base shear reduction ratio of the structure while maintaining the total number of dampers, thereby effectively improving the overall seismic performance.

本研究旨在通过优化一种新型铁基形状记忆合金剪切-摩擦混合阻尼器（FSMA-SFHD）的空间布局，提高半刚性钢框架的抗震弹性，并促进工程应用。本文提出的FSMA-SFHD将Fe-SMA剪切板与摩擦单元结合，将Fe-SMA优异的低周疲劳抗力与摩擦单元在小振幅振动下的快速响应相结合，从而在整个地震周期内实现高效的能量耗散。为了准确模拟其力学行为，基于OpenSees平台建立了FSMA-SFHD的有限元模型，并通过对比力学性能试验验证了模型的有效性。建立了综合考虑层间漂移比、楼板加速度和顶板位移的多目标性能指标，并采用保持精英遗传算法对固定阻尼器数量下的阻尼器位置进行优化。对三间十层和四间八层框架的实例研究表明，优化布局优于随机配置：优化结果表明，与随机阻尼器布置相比，所提出的方案在保持阻尼器总数的同时，显著提高了结构的峰值位移减震率和基础剪力减震率，从而有效地提高了结构的整体抗震性能。

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引用次数: 0

Axial compressive behavior of an asymmetric steel columns in modular emergency buildings 模块化应急建筑中不对称钢柱的轴压特性

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

Journal of Constructional Steel Research

Pub Date : 2026-01-17 DOI: 10.1016/j.jcsr.2026.110251

Jiadi Liu , Yu Zhang , Shuang Lyu , Yang Liu , Zhihua Chen , Peng Sun , Qi An

Cold-formed thin-walled steel columns with asymmetric complex edges are widely used in the modular emergency buildings, yet the axial compressive behavior of these columns remains unclear. In this study, 32 specimens were tested under uniaxial compression to clarify failure modes and axial compressive capacity. Results revealed that specimens loaded through long flanges exhibit superior resistance to strength failure, while short-flange loaded specimens showed enhanced stability performance. Additionally, a finite element model (FEM) was developed and experimentally validated. Besides, the finite strip analysis revealed that specimens shorter than 900 mm primarily experienced distortional and local buckling, while those exceeding this length exhibited overall buckling. Finally, a theoretical calculation equation, based on the Direct Strength Method (DSM) formula in AISI, was proposed by integrating numerical simulation results and buckling mode contributions, resulting in improved prediction accuracy for critical buckling modes of varying slenderness ratios. The key results reveal the failure modes of cold-formed steel columns with slenderness ratios and propose the DSM-based theoretical equations, offering a reference for future engineering applications in the modular emergency buildings.

具有非对称复杂边的冷弯薄壁钢柱广泛应用于模块化应急建筑中，但其轴压性能尚不清楚。本研究对32个试件进行了单轴压缩试验，以明确破坏模式和轴压能力。结果表明，长法兰加载的试件具有较好的抗强度破坏性能，短法兰加载的试件具有较好的稳定性。建立了有限元模型，并进行了实验验证。此外，有限条分析表明，短于900 mm的试件主要经历扭曲和局部屈曲，而超过900 mm的试件则表现为整体屈曲。最后，基于AISI中的直接强度法（DSM）公式，将数值模拟结果与屈曲模态贡献相结合，建立了理论计算公式，提高了变长细比下临界屈曲模态的预测精度。重点研究结果揭示了长细比冷弯型钢柱的破坏模式，并提出了基于dsm的理论方程，为今后模块化应急建筑的工程应用提供了参考。

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引用次数: 0