IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-17 DOI: 10.1016/j.istruc.2026.111127

Wei-hui Zhong , Xuan Zhang , Chen Chen , Wen-hao Fang

Energy dissipation technology enhances building safety by dissipating seismic energy while providing economic benefits. This paper proposes a novel self-centering dual-stage energy-dissipative brace (SCDEB). First, the conceptual design of SCDEB is presented, and its theoretical hysteretic model is established based on mechanical principles. Parametric analysis is performed on SCDEB through numerical simulation. The results demonstrate that both the preload and stiffness of the disc spring group significantly influence the bearing capacity and self-centering capability of SCDEB. Subsequently, a finite element model of the steel frame substructure equipped with SCDEB (SF-SCDEB) is established. Even under a drift ratio of ±2.0 %, the SF-SCDEB exhibits a residual drift ratio of only 0.34 %, demonstrating excellent self-centering capability. Furthermore, a series of nonlinear time history analyses conducted on a case-study structure confirm that the SCDEB serves to effectively control and diminish both the maximum and residual inter-story drift ratios across multiple levels of seismic intensity. Through rational design and application of SCDEB, it can effectively reduce seismic damage to building structures and accelerate post-earthquake recovery.

消能技术在提供经济效益的同时，通过消能来提高建筑的安全性。提出了一种新型自定心双级耗能支撑（SCDEB）。首先，提出了SCDEB的概念设计，并基于力学原理建立了其滞回理论模型。通过数值模拟对SCDEB进行了参数化分析。结果表明，盘形弹簧组的预紧力和刚度对SCDEB的承载能力和自定心能力均有显著影响。随后，建立了安装SCDEB的钢框架子结构有限元模型（SF-SCDEB）。在漂移比为±2.0 %的情况下，SF-SCDEB的残余漂移比仅为0.34 %，具有良好的自定心能力。此外，对一个实例结构进行的一系列非线性时程分析证实，SCDEB可以有效地控制和减小多个地震烈度水平上的最大和剩余层间漂移比。通过合理设计和应用SCDEB，可以有效减少地震对建筑结构的破坏，加快灾后恢复。

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引用次数: 0

Time-dependent seismic fragility assessment of self-centering tall-pier bridges considering long-term prestress loss 考虑长期预应力损失的自定心高墩桥梁地震易损性时变评价

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-17 DOI: 10.1016/j.istruc.2026.111100

Xin Shi , Tong Guo , Ruizhao Zhu , Shiyan Cheng , Yu Xia , Qiang Han

The time-dependent loss of prestress in self-centering (SC) tall-pier bridges can degrade their recovery and seismic performance, affecting post-earthquake behavior. Thus, this paper proposes a time-dependent vulnerability analysis method, where prestress loss is considered the primary degradation effect, to assess the long-term seismic performance of the designed SC tall-pier bridges. The study analyzes the time-dependent fragility of both the components and the system of the bridge throughout its entire service life. The relationship between prestress loss and structural vulnerability is revealed, providing valuable insights into the time-dependent seismic performance of self-centering tall-pier bridges. The results indicate that over the full service life of the bridge, the bearings are more vulnerable than the tall pier and rocking base, and the tall pier experiences performance degradation at a faster rate than the rocking base. Additionally, compared to the dimensionless tilt angle θ/α_c, pier section curvature ductility μ_ϕ, and bearing displacement d are more suitable as indicators for assessing the long-term performance degradation of self-centering tall pier bridges. The study highlights the importance of incorporating long-term deterioration mechanisms in the seismic performance assessment of SC tall-pier bridges.

自定心高墩桥梁预应力随时间的损失会降低桥梁的恢复和抗震性能，影响其震后行为。因此，本文提出了一种考虑预应力损失为主要退化效应的时效易损性分析方法，以评估设计的SC高墩桥梁的长期抗震性能。该研究分析了桥梁在整个使用寿命期间构件和系统的时间依赖性脆弱性。揭示了预应力损失与结构易损性之间的关系，为自定心高墩桥梁的时变抗震性能提供了有价值的见解。结果表明，在桥梁全寿命期内，支座比高墩和摇基更脆弱，且高墩的性能退化速度比摇基快。与无量纲倾斜角θ/αc相比，桥墩截面曲率延性μ φ和支座位移d更适合作为自定心高墩桥长期性能退化的评价指标。该研究强调了在SC高墩桥梁抗震性能评估中纳入长期劣化机制的重要性。

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引用次数: 0

Experimental, analytical and numerical study of hybrid timber-steel connections with steel fuses 带钢保险丝的木-钢混合连接的试验、分析和数值研究

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-17 DOI: 10.1016/j.istruc.2025.111028

Reyhaneh Hosseini, Hamid R. Valipour, Daniel O’Shea

The structural behaviour of eight full scale hybrid glued laminated timber (GLT) beam to steel column connections with glued-in high strength (8.8 grade) steel rods, and replaceable mild (4.6 grade) steel fuses were investigated by static and cyclic laboratory testing of T-shape beam-to-column subassemblies. Apart from the peak load, stiffness, failure mode, ductility and energy dissipation capacity, the stiffness and strength degradation of the hybrid connections were evaluated by replacing the mild steel fuses and testing some of the subassemblies up to six times. The test results demonstrated the potential of bonded-in high strength steel rods with mechanical couplers to develop hybrid connections that can be easily dismantled and replaced. The strength and stiffness degradation of the connections observed after six loading repeats was 18.3 % and 33.5 %, respectively. Simple mechanistic models are proposed to estimate the short-term service stiffness and ultimate bending moment capacity of the hybrid connections with replaceable mild steel fuses. Nonlinear 3D finite element simulation was used to conduct parametric studies and to provide insights into the effects of bolt pre-tensioning and fuse grade.

通过t形梁柱组件的静态和循环实验室测试，研究了8个全尺寸混合胶合层合木材（GLT）梁与钢柱连接的结构性能，这些连接采用胶合高强度（8.8级）钢棒和可更换的轻度（4.6级）钢保险丝。除了峰值荷载、刚度、破坏模式、延性和耗能能力外，还通过更换低碳钢保险丝和对部分组件进行多达6次的测试来评估混合连接的刚度和强度退化。测试结果表明，将高强度钢棒与机械耦合器结合在一起，可以形成易于拆卸和更换的混合连接。6次重复加载后，连接的强度和刚度退化率分别为18.3 %和33.5 %。提出了可更换低碳钢熔断器混合连接短期使用刚度和极限弯矩承载力的简单力学模型。非线性三维有限元模拟用于进行参数研究，并深入了解螺栓预张紧和熔断器等级的影响。

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引用次数: 0

Size effect on tensile strength parallel to grain of structural bamboo scrimber 结构竹材平行晶粒抗拉强度的尺寸效应

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-17 DOI: 10.1016/j.istruc.2026.111129

Zhiwei Huang, Xiaofan Ye, Hongwei Su, Ye Sheng, Nan Guo

The size effect on strength is an important factor for determining the design values of material strength according to reliability theory. To facilitate the development of technical specifications for structural bamboo scrimber, it is essential to address the size effect on its strength. In this paper, experimental research on 600 specimens was conducted. The variation in the average and characteristic values of tensile strength (parallel to grain) of bamboo scrimber with thickness, width, and length was studied. The slope method and the shape parameter method were applied to account for the influence of the size effect on the tensile strength parallel to the grain of bamboo scrimber. The bamboo/wood test specifications of China, the United States and Japan were compared. Based on this comparison, the influence of cross-sectional area on the tensile strength parallel to the grain of bamboo scrimber was evaluated. The results show that the tensile properties of bamboo scrimber exhibit distinct dimensional dependencies. The slope method provides a better fit to the size effect than the shape parameter method. The width and length adjustment coefficients obtained using the slope method are greater than the corresponding coefficients given in ASTM D1990–19. However, due to limitations in production thickness, the thickness size effect is negligible. The size effects of thickness, width, and length on the tensile strength parallel to the grain of bamboo scrimber can be calculated by one proposed formula. The adjustment coefficients for the size effects of thickness, width, and length on the characteristic values of tensile strength can be taken as 0, 0.39 and 0.30, respectively. The adjustment coefficients for the size effects of thickness, width, and length on the average tensile strength can be taken as 0, 0.27 and 0.23, respectively. Differences in specimen sizes across different specifications can be attributed to area-dependent size effect, which can be calculated using another proposed formula. The area size adjustment coefficients for the characteristic value and average value of tensile strength of bamboo scrimber can be taken as 0.094 and 0.074, respectively.

根据可靠度理论，尺寸对强度的影响是确定材料强度设计值的重要因素。为了促进结构竹材技术规范的发展，必须解决尺寸对其强度的影响。本文对600个试件进行了实验研究。研究了竹材的抗拉强度平均值和特征值随厚度、宽度和长度的变化规律。采用斜率法和形状参数法分析了尺寸效应对竹材平行纹路抗拉强度的影响。比较了中国、美国和日本的竹/木试验规范。在此基础上，评价了横截面积对竹材平行纹路抗拉强度的影响。结果表明，竹材的拉伸性能表现出明显的尺寸依赖性。斜率法比形状参数法能更好地拟合尺寸效应。用斜率法得到的宽度和长度调整系数均大于ASTM D1990-19给出的相应系数。但由于生产厚度的限制，厚度尺寸的影响可以忽略不计。竹材厚度、宽度和长度对竹材平行颗粒拉伸强度的影响可以用一个公式来计算。厚度、宽度、长度对抗拉强度特征值的尺寸效应调整系数分别取为0、0.39、0.30。厚度、宽度和长度对平均抗拉强度尺寸效应的调节系数分别取为0、0.27和0.23。不同规格的试样尺寸的差异可归因于面积依赖的尺寸效应，这可以使用另一个提出的公式计算。竹材抗拉强度特征值和平均值的面积大小调整系数分别为0.094和0.074。

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引用次数: 0

Carbon emission assessment of basalt fiber and basalt fiber-reinforced polymer (BFRP) reinforced/strengthened concrete structures 玄武岩纤维及玄武岩纤维增强聚合物（BFRP）增强/加固混凝土结构的碳排放评价

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-16 DOI: 10.1016/j.istruc.2026.111128

Zheqi Peng , Xin Wang , Xia Liu , Lining Ding , Biyun Tang , Zhishen Wu

Basalt fiber and basalt fiber-reinforced polymer (BFRP) material are known for their high mechanical performance, excellent durability, and sustainability features. In this study, the embodied carbon emissions of basalt fiber, BFRP grid, and BFRP bar are calculated and compared with those of other fibers and FRPs. Then, the carbon emissions of a FRP grid-strengthened structure and a FRP bar-reinforced concrete structure are evaluated. It is estimated that the emission factor (EF) of basalt fiber ranges from 0.98 to 3.87 kgCO₂e/kg, depending on the manufacturing method and scale, which is significantly lower than that of carbon and aramid fibers. With the novel automatic continuous weaving-molding (ACWM) manufacturing method, the EF of BFRP grid is 3.27 kgCO₂e/kg. In the FRP grid-strengthening case study, it is found that a thicker FRP grid significantly reduces the carbon emissions for unit flexural capacity enhancement. For 5 mm-thick CFRP, GFRP, and BFRP grid-strengthened structures, the carbon emissions for unit flexural capacity enhancement are reduced to 6.26, 8.39, and 6.90 kgCO₂e/kN/m, respectively, from 8.57 kgCO₂e/kN/m for the section enlarged structure. In another case study of an offshore reinforced structure, under the stiffness equivalent substitution, the life-cycle carbon emissions for CFRP, AFRP, GFRP, BFRP, and steel reinforced concrete are 1448, 1795, 1749, 1460, and 1530 tCO₂e, respectively.

玄武岩纤维和玄武岩纤维增强聚合物（BFRP）材料以其高机械性能、优异的耐久性和可持续性而闻名。本研究计算了玄武岩纤维、BFRP格栅和BFRP筋的隐含碳排放量，并与其他纤维和frp的隐含碳排放量进行了比较。然后，对FRP格栅加固结构和FRP筋混凝土结构的碳排放进行了评估。根据制备方法和规模的不同，玄武岩纤维的排放系数（EF）在0.98 ~ 3.87 kgCO2e/kg之间，明显低于碳纤维和芳纶纤维。采用新颖的自动连续编织成型（ACWM）制造方法，BFRP格栅的EF为3.27 kgCO2e/kg。在FRP格栅加固案例研究中发现，较厚的FRP格栅可以显著降低单位抗弯能力增强的碳排放。对于5 mm厚CFRP、GFRP和BFRP网格加固结构，单位抗弯能力增强的碳排放量分别从截面扩大结构的8.57 kgCO2e/kN/m降低到6.26、8.39和6.90 kgCO2e/kN/m。在另一个海上钢筋结构的案例研究中，在刚度等效替代下，CFRP、AFRP、GFRP、BFRP和钢筋混凝土的生命周期碳排放量分别为1448、1795、1749、1460和1530 tCO2e。

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引用次数: 0

Surface damage detection of bridge piers based on UAV geometry and multi-slope flight path method 基于无人机几何和多坡航迹法的桥墩表面损伤检测

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-16 DOI: 10.1016/j.istruc.2026.111097

Xinfeng Yin , Yong Zhou , Zhi Zeng , Linsong Wu

Planning unmanned aerial vehicle (UAV) flight paths and identifying surface damage in the 3D models remain critical challenges in structural health monitoring. This study proposes a novel method for detecting surface damage on bridge piers by integrating the UAV-based geometric flight path planning, the multi-slope route strategy, and the optimized deep learning technique. First, the bridge pier structure is simplified as a hexahedron, and a systematic photographic strategy is designed to capture the high-resolution images of its four vertical surfaces. Second, a rapid 3D reconstruction framework leveraging the Structure from Motion (SfM) algorithm and the orthographic projection mapping is developed to generate detailed pier models. Finally, the improved YOLOv8 network is further enhanced through transfer learning to improve crack and defect detection accuracy in projected surface images. Experimental validation on a real bridge pier achieves a median image resolution of 0.0035 m/pixel and a point cloud root mean square (RMS) error of 0.00278 m. The optimized YOLOv8s network demonstrates effective detection and classification of bridge pier surface damage through transfer learning. These results indicate that UAV technology has significant potential for non-contact damage detection on bridge pier surfaces.

规划无人机（UAV）的飞行路径和识别三维模型中的表面损伤仍然是结构健康监测的关键挑战。本文提出了一种基于无人机的几何航迹规划、多坡航迹策略和优化深度学习技术相结合的桥墩表面损伤检测新方法。首先，将桥墩结构简化为六面体，并设计了系统的摄影策略来捕获其四个垂直表面的高分辨率图像。其次，利用运动结构（SfM）算法和正交投影映射开发了快速三维重建框架，以生成详细的桥墩模型。最后，通过迁移学习进一步增强改进后的YOLOv8网络，提高对投影表面图像的裂纹和缺陷检测精度。在真实桥墩上进行实验验证，图像的中位数分辨率为0.0035 m/pixel，点云均方根误差为0.00278 m。优化后的YOLOv8s网络通过迁移学习对桥墩表面损伤进行了有效的检测和分类。这些结果表明，无人机技术在桥梁桥墩表面非接触损伤检测方面具有巨大的潜力。

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引用次数: 0

Investigation into the shear performance of pre-damaged RC beams reinforced with ECC and FRP grid ECC - FRP格栅预损伤钢筋混凝土梁抗剪性能研究

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-16 DOI: 10.1016/j.istruc.2026.111130

Long-yu Cong , Fang Zhang , Yong-jiu Qian

This study employed fiber reinforced polymer (FRP) grid- Engineered Cementitious Composite (ECC) composites as a shear strengthening layer to repair pre-damaged reinforced concrete (RC) beams. Eight RC beam specimens were fabricated, with variables including strengthening scheme, degree of pre-damage, and shear span-to-depth ratio (λ). Four-point bending tests were conducted to investigate the shear capacity of these specimens. Experimental results demonstrated that ECC-only strengthening restored pre-damaged beams to baseline capacity but failed to provide further enhancement. For undamaged RC beams, both ECC and FRP-ECC strengthening yielded comparable effectiveness, failing to fully utilize the tensile properties of FRP. Conversely, FRP-ECC jointly strengthening demonstrated exceptional efficacy for pre-damaged beams. Notably, shear strengthening effectiveness did not decrease with increasing pre-damage severity; moderate pre-damage facilitated greater load sharing by FRP. Increased λ promoted more extensive diagonal cracking, mitigating FRP stress concentrations and thereby improving strengthening performance. Finally, a shear capacity calculation method for pre-damaged RC beams was developed based on the truss-arch model, with accuracy validated against experimental data from this study and referenced literatures.

本研究采用纤维增强聚合物（FRP）网格-工程胶凝复合材料（ECC）复合材料作为剪切增强层修复预损伤的钢筋混凝土（RC）梁。采用加固方案、预损伤程度、抗剪跨深比（λ）等参数，制作了8根钢筋混凝土梁试件。进行了四点弯曲试验来研究这些试件的抗剪能力。实验结果表明，仅采用ecc加固可将预损伤梁恢复到基线承载力，但不能提供进一步的增强。对于未损坏的RC梁，ECC和FRP-ECC加固都产生了相当的效果，但未能充分利用FRP的拉伸性能。相反，FRP-ECC联合加固对预损伤梁表现出卓越的效果。值得注意的是，剪切强化效果不随预损伤严重程度的增加而降低；适度的预损伤有助于FRP更好地分担荷载。增加λ促进更广泛的对角开裂，减轻FRP应力集中，从而提高强化性能。最后，提出了一种基于桁架-拱模型的预损伤RC梁抗剪承载力计算方法，并通过本研究的实验数据和参考文献验证了其准确性。

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引用次数: 0

Earthquake-induced sloshing dynamics of rigid tanks considering seismic resonance: hydrodynamic loads and baffle-based mitigation 考虑地震共振的刚性储罐的地震诱导晃动动力学：水动力载荷和挡板减振

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-16 DOI: 10.1016/j.istruc.2026.111134

Cong Zhang , Hongmei Wan , Yiliang Zhou , Yancheng Dong

During earthquakes, liquid storage tanks may experience significant sloshing due to seismic induced resonance, potentially leading to structural failure of the tank-liquid system. This study employs OpenFOAM numerical simulations and shaking table tests to examine the dynamic behavior of sloshing tanks and the resulting hydrodynamic loads, using 14 seismic waves that cover resonance and low- to high- frequency seismic conditions. The results show that seismic resonance produces markedly stronger sloshing response than the non-resonant cases. Under resonant conditions, the hydrodynamic pressure along the tank wall exhibits a spindle-shaped profile, with the maximum pressure occurring near the free surface. However, under non-resonance conditions, the pressure distribution is triangular, with the maximum pressure occurring near the tank bottom. Seismic resonance significantly amplifies the base shear force and overturning moment of the tank; even with comparable shear forces, the overturning moment under resonance can be 1.74–2.14 times higher than that under non-resonant conditions. The installation of baffles in the upper convective-dominated region of the tank effectively reduces the resonant base shear force and overturning moment, achieving suppression rates of 45–60 %, whereas placement in the bottom region yields only 15–25 % reduction. These findings provide insights for seismic performance of storage tanks under seismic resonance and offer practical guidance for the aseismic design of storage tanks.

地震发生时，储液罐可能会由于地震诱发共振而产生明显的晃动，从而可能导致储液系统的结构破坏。本研究采用OpenFOAM数值模拟和振动台试验来检验晃动水箱的动力特性和由此产生的水动力载荷，使用14个地震波，涵盖共振和低频到高频地震条件。结果表明，地震共振情况下的晃动响应明显强于非共振情况。在共振条件下，沿槽壁的动水压力呈纺锤形分布，最大压力出现在自由面附近。然而，在非共振条件下，压力分布呈三角形，最大压力出现在罐底附近。地震共振显著放大了储罐的基底剪力和倾覆力矩；在剪力相当的情况下，共振条件下的倾覆力矩比非共振条件下的倾覆力矩高1.74 ~ 2.14倍。在罐体上部对流为主区域安装折流板可有效降低共振基底剪力和倾覆力矩，抑制率可达45-60 %，而在底部区域安装折流板仅能降低15-25 %。研究结果对储罐在地震共振作用下的抗震性能有一定的启示，对储罐的抗震设计具有实际指导意义。

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引用次数: 0

Experimental and numerical study on the fire resistance of foam concrete wall panels under standard fire exposure 标准火暴露条件下泡沫混凝土墙板耐火性能的试验与数值研究

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-16 DOI: 10.1016/j.istruc.2026.111082

Xiaomeng Ding , Yujie Huang , Kezheng Wu , Zhongfan Chen , Ming Xu , Guangyou Li

This study investigates the fire resistance performance of foam concrete (FC) wall panels under the ISO 834 standard fire. A foam concrete mix with 750 kg/m³ density was developed and used to fabricated full-scale wall specimens with thicknesses of 100, 150, and 200 mm. Standard fire tests were conducted to evaluate the thermal insulation and integrity performance of the walls, and the temperature distributions were recorded at different depths and joint regions. The results demonstrated that FC panels exhibited excellent fire resistance properties, with temperature rises on the unexposed surface remaining below 15℃ after the prescribed exposure duration. Joints were identified as the weakest zones due to mismatched thermal expansion between the mortar and FC, resulting in microcracking and localized deterioration. Finite element heat transfer model developed in ABAQUS accurately simulated temperature evolution, validating a simplified specific heat method that accounts for moisture effects. Parametric studies demonstrated that reduced density and increased moisture content improve fire resistance of FC walls by enhancing latent heat absorption. The residual load-bearing capacity of numerical analysis showed that the bending strength of FC strip panels decreased by 34 % after 120 mins of fire exposure. Furthermore, a practical calculation method for evaluating the post-fire flexural capacity of foam concrete wall panels is proposed based on numerical results. These findings confirm that high-strength, high-thermal-resistance FC is a promising material for integrated structural and thermal systems, offering both safety and energy efficiency in modern building applications.

本文研究了泡沫混凝土（FC）墙板在ISO 834标准下的防火性能。开发了密度为750 kg/m3的泡沫混凝土混合料，并用于制作厚度为100、150和200 mm的全尺寸墙体试件。进行了标准防火试验，评价墙体的保温性能和完整性，并记录了不同深度和接缝区域的温度分布。结果表明，FC板具有优异的耐火性能，在规定的暴露时间后，未暴露表面的温升保持在15℃以下。由于砂浆与碳纤维之间热膨胀不匹配，接缝被认为是最薄弱的区域，导致微开裂和局部劣化。在ABAQUS中建立的有限元传热模型准确地模拟了温度演变，验证了考虑水分影响的简化比热法。参数研究表明，降低密度和增加含水率通过增强潜热吸收来提高FC墙的耐火性。数值分析结果表明，FC条形板在火灾作用120 min后，其抗弯强度降低了34% %。在此基础上，提出了泡沫混凝土墙板火灾后抗弯承载力的实用计算方法。这些发现证实，高强度、高热阻FC是一种很有前途的综合结构和热系统材料，在现代建筑应用中既安全又节能。

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引用次数: 0

Bayesian optimization-enhanced vision transformer for damage detection in steel truss structures using continuous wavelet transform analysis 基于连续小波变换分析的贝叶斯优化增强视觉变形钢桁架结构损伤检测

IF 4.3 2区工程技术 Q1 ENGINEERING, CIVIL

Structures

Pub Date : 2026-01-16 DOI: 10.1016/j.istruc.2026.111059

Murat Hi̇çyılmaz

The main contribution of this paper is to optimize the hyperparameters of the Vision transformer (ViT) architecture using an adaptive Bayesian optimization process that provides superior performance compared to state-of-the-art models in terms of accuracy and efficiency while remaining within acceptable limits in terms of computational efficiency. For this purpose, a Bayesian-optimized Image Transformer model (CwBot) is proposed for damage detection in steel truss structures using continuous wavelet transform (CWT) analysis. CWT spectrograms generated from a 72-bar steel truss model and measurements of a real steel truss bridge are considered to better reveal the complex dynamic behavior of steel truss structures. The ViT hyperparameters including patch size, embedding size, transformer depth, multi-head attention heads, MLP size, learning rate, and batch size are optimized and compared with seven different state-of-the-art transfer learning models. The proposed model achieves 93.29 % accuracy for the 72-bar steel truss and 98.43 % accuracy for the real steel truss bridge, outperforming other models.

本文的主要贡献是使用自适应贝叶斯优化过程优化视觉变压器（ViT）架构的超参数，与最先进的模型相比，该过程在精度和效率方面提供了卓越的性能，同时在计算效率方面保持在可接受的范围内。为此，利用连续小波变换（CWT）分析，提出了一种贝叶斯优化图像变换模型（CwBot），用于钢桁架结构的损伤检测。考虑了由72杆钢桁架模型和实际钢桁架桥的实测数据生成的CWT谱图，以更好地揭示钢桁架结构的复杂动力特性。优化了ViT超参数，包括贴片大小、嵌入大小、变压器深度、多头注意头、MLP大小、学习率和批量大小，并与7种不同的最先进的迁移学习模型进行了比较。该模型对72杆钢桁架的精度为93.29 %，对实际钢桁架桥梁的精度为98.43 %，优于其他模型。

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引用次数: 0

Structures最新文献