Engineering Structures最新文献_第6页

Experimental study on shear performance of prefabricated HSS-UHPC composite beam with perfobond strip connectors 使用 perfobond 带状连接件的预制 HSS-UHPC 复合梁抗剪性能实验研究

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-21 DOI: 10.1016/j.engstruct.2024.119318

Shaohua He , Defeng Zhou , Baisheng Bai , Changxi Liu , You Dong

High-strength steel (HSS)-to-ultra-high performance concrete (UHPC) composite beams are highly competitive in prefabricated bridge constructions. This paper employs a four-point loading system to evaluate the load-bearing mechanism of prefabricated HSS-UHPC composite beams under shear loadings. Five large-scale composite beam specimens are prepared and tested, with variations in parameters such as steel plate perforation form, arrangement of perforated plate, UHPC slab width, and presence of slab tapered haunches. The composite beams' failure modes, shear stiffness, load-deflection behavior, strain profiles, and interfacial slippage characteristics are presented and discussed. Experimental results indicate that the prefabricated HSS-UHPC composite beams exhibit large shear stiffness and favorable ductility, and the composite beams with tapered haunches demonstrate a 26.9 % higher shear stiffness than those without. However, this improvement is accompanied by a 26.8 % reduction in initial cracking load, attributed to the upward movement of the neutral axis. Replacing circular holes in the perforated steel plate with puzzle-shaped openings increases the shear stiffness and ductility of the composite beam by 79.0 % and 47.4 %, respectively. Additionally, the adoption of double-row perforated plates further improves the shear performance of the composite beam due to the more intensive layout of PBLs in shear-span regions. The study also examines the applicability of existing codes and typical shear capacity formulas to HSS-UHPC composite beams and proposes a predictive model to calculate the shear capacity of the beams accurately. The proposed equations provide a reasonable methodology for determining the shear resistance of such composite beams.

高强度钢（HSS）-超高性能混凝土（UHPC）复合梁在预制桥梁建筑中具有很强的竞争力。本文采用四点加载系统来评估预制 HSS-UHPC 复合梁在剪切荷载作用下的承载机理。本文制备并测试了五个大型复合梁试件，这些试件在钢板穿孔形式、穿孔板布置、UHPC 板宽度和板锥形后缘等参数上存在差异。对复合梁的破坏模式、剪切刚度、荷载-挠度行为、应变曲线和界面滑移特性进行了介绍和讨论。实验结果表明，预制 HSS-UHPC 复合梁具有较大的剪切刚度和良好的延展性。然而，在提高剪切刚度的同时，初始开裂荷载却降低了 26.8%，这归因于中性轴的上移。用拼图形开口取代穿孔钢板上的圆孔，可使复合梁的剪切刚度和延展性分别提高 79.0% 和 47.4%。此外，采用双排穿孔钢板还能进一步提高复合梁的抗剪性能，这是因为在剪跨区域采用了更密集的 PBL 布局。该研究还检验了现有规范和典型剪切承载力公式对 HSS-UHPC 复合梁的适用性，并提出了一个预测模型来精确计算梁的剪切承载力。所提出的公式为确定此类复合梁的抗剪能力提供了合理的方法。

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引用次数: 0

Bending performance of nail laminated timber (NLT): Experiments and probabilistic modelling based on Monte Carlo simulation 钉层压材（NLT）的弯曲性能：基于蒙特卡洛模拟的实验和概率模型

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-20 DOI: 10.1016/j.engstruct.2024.119317

Wei Feng , Minjuan He , Jiajia Ou , Zheng Li

Nail laminated timber (NLT) is gaining attention due to the advantages of low cost, simple fabrication and distinctive aesthetic. However, research is still limited on the design of NLT panels. To investigate the bending behavior of NLT, probabilistic modelling method based on Monte Carlo simulation was presented in this study. Firstly, two kinds of dimension lumber were respectively used as the laminations of the NLT specimens, and bending tests were conducted on both the laminations and the NLT. The failure modes and the bending properties of the NLT were analyzed. Then, a random sampling model for the laminations was developed considering the material uncertainty. The simulated laminations were virtually laminated into NLT, and large-scale modelling on the NLT was conducted. Finally, the modelling was validated by test results and parametric analysis was further carried out. Results showed that the probabilistic modelling is capable of predicting the mean value as well as the variability of the NLT’s bending properties. The bending strength of NLT is influenced primarily by the mean bending strength of its laminations. However, a lower mean value and higher variability in the bending strength of NLT would result from the laminations with lower variability in the modulus of elasticity, higher variability in the bending strength and poorer correlation between the bending strength and the modulus of elasticity.

钉层压木材（NLT）具有成本低、制造简单和美观独特等优点，因此越来越受到人们的关注。然而，有关 NLT 板材设计的研究仍然有限。为了研究 NLT 的弯曲行为，本研究提出了基于蒙特卡洛模拟的概率建模方法。首先，分别使用两种规格木材作为无梁板试样的层压板，并对层压板和无梁板进行了弯曲试验。分析了 NLT 的破坏模式和弯曲性能。然后，考虑到材料的不确定性，建立了层压材料的随机抽样模型。模拟层压板被虚拟层压到 NLT 中，并对 NLT 进行了大规模建模。最后，通过测试结果对建模进行了验证，并进一步进行了参数分析。结果表明，概率建模能够预测 NLT 弯曲性能的平均值和变异性。无砟轨道板的弯曲强度主要受其板层平均弯曲强度的影响。然而，如果层压材料的弹性模量变化较小，弯曲强度变化较大，弯曲强度与弹性模量之间的相关性较差，则无砟轨道板的弯曲强度平均值较低，变化较大。

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引用次数: 0

Impact performance of curved double arrow and stacked Miura-ori panels 弧形双箭板和叠层三浦织板的冲击性能

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-20 DOI: 10.1016/j.engstruct.2024.119319

Zhejian Li , Lingfeng Wang , Ruofei Yan , Yuanpeng He , Hong Hao , Yuanzheng Lin , Wensu Chen

The design methods for creating curved stacked structures of double arrow and Miura-ori are proposed and the impact performances of the two novel curved sandwich panels with double arrow and stacked Miura origami core are examined respectively for the first time. A specimen of curved double arrow panel is prepared and subjected to impact testing using a drop weight impact system and the test results are then used for validating the numerical models. Numerical simulations are conducted to examine the impact performance of the proposed curved double arrow and stacked Miura-ori sandwich panels for the first time. Additionally, existing curved honeycomb panels with the same core densities are analyzed for comparison. Various impacting scenarios, including different impact speeds, impactor shapes, and impactor dimensions are considered. Key performance indicators such as indentation depth, back plate deflection, energy absorption, deformation mode and impact force-displacement curves are utilized to assess the impact resistance of the three curved sandwich panels. The curved panel with stacked Miura-ori core exhibits superior performance across most impact scenarios, attributed to its relatively high crushing resistance and the constraining effects from adjacent unit cells. The double arrow curved panel demonstrates good performance against spherical projectiles at high impact velocities due to its long unit cell in the longitudinal direction, leading to a delayed rupture of the skin plates. Both curved double arrow and stacked Miura-ori panels show lower sensitivity to the variations in impact scenarios than curved honeycomb panel, indicating a promising impact-resistant application potential for structures with curved surfaces such as train and airplane.

提出了双箭头和三浦折纸曲面叠层结构的设计方法，并首次分别研究了双箭头和三浦折纸叠层两种新型曲面夹芯板的冲击性能。制备了曲面双箭头板试样，并使用落重冲击系统进行了冲击测试，测试结果用于验证数值模型。通过数值模拟，首次检验了拟议的弧形双箭板和叠层 Miura-ori 夹层板的冲击性能。此外，还对具有相同芯材密度的现有弧形蜂窝板进行了分析比较。考虑了各种撞击情况，包括不同的撞击速度、撞击器形状和撞击器尺寸。利用压痕深度、背板挠度、能量吸收、变形模式和冲击力-位移曲线等关键性能指标来评估三种曲面夹层板的抗冲击性能。堆叠三浦ori芯材的弧形面板在大多数冲击情况下都表现出优异的性能，这归功于其相对较高的抗压性以及相邻单元格的约束效应。双箭头弧形面板由于其纵向单元较长，导致表皮板延迟破裂，因此在高冲击速度下具有良好的抗球形弹丸性能。与弯曲蜂窝板相比，弯曲双箭板和堆叠三浦ori 板对撞击情景变化的敏感性较低，这表明在火车和飞机等具有弯曲表面的结构中，抗冲击应用潜力巨大。

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引用次数: 0

Experimental study of reinforced concrete rocking columns with steel tubes under cyclic loading 循环荷载下带钢管的钢筋混凝土摇动柱的实验研究

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-20 DOI: 10.1016/j.engstruct.2024.119304

Fanfu Bu, Chun Jiang, Xilin Lu, Huanjun Jiang

To reduce damage and enhance the seismic resilience of reinforced concrete (RC) columns, this study introduces a new type of RC rocking column installed with steel tubes for end protection and steel angles as external dampers to enhance the energy dissipation capacity. Six full-scale specimens including four RC rocking columns without steel angles and two with steel angles were tested under cyclic loading. The results demonstrate that the proposed end protection measure significantly mitigates the damage to RC rocking columns. The residual deformation of specimens was small after testing. As the axial compression ratio increases, the strength of RC rocking columns also increases. However, a higher axial force results in greater damage and increased residual deformation. Steel angles significantly enhance the strength, stiffness, and energy dissipation capacity of RC rocking columns. Additionally, the repair of the RC rocking column is straightforward, and the recovery of its function is rapid after strong earthquakes.

为减少钢筋混凝土（RC）柱的损坏并提高其抗震能力，本研究介绍了一种新型 RC 摇动柱，该摇动柱安装了钢管作为端部保护，并安装了角钢作为外部阻尼器，以提高消能能力。在循环荷载下测试了六个全尺寸试样，包括四个不带角钢的 RC 摇动柱和两个带角钢的 RC 摇动柱。结果表明，所建议的端部保护措施能显著减轻 RC 摇动柱的损坏。试验后试件的残余变形很小。随着轴向压缩比的增加，RC 摇动柱的强度也随之增加。然而，更大的轴向力会导致更大的损坏和残余变形。角钢能明显提高 RC 摇动柱的强度、刚度和耗能能力。此外，RC 摇动柱的修复非常简单，在强震后可迅速恢复其功能。

引用次数: 0

Durability assessment of ultra-high-performance concrete (UHPC) and FRP grid-reinforced UHPC plates under marine environments 超高性能混凝土（UHPC）和 FRP 网格加固的 UHPC 板材在海洋环境下的耐久性评估

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-19 DOI: 10.1016/j.engstruct.2024.119313

Jun-Jie Zeng , Zhi-Hao Hao , Hou-Qi Sun , Wei-Bin Zeng , Tian-Hui Fan , Yan Zhuge

Fiber reinforced polymer (FRP) reinforced ultra-high-performance concrete (UHPC) structures not only tackle the issue of insufficient stiffness encountered in FRP reinforced normal concrete structures, but also offer a promising solution to address the durability challenges present in conventional reinforced concrete structures. While some studies have explored the mechanical properties of FRP reinforced UHPC (referred to as FRU), their durability performance remains unexplored. This paper presents a comprehensive durability assessment of FRU and UHPC plates, incorporating steel and polyethylene (PE) fibers, to compare their performance under simulated marine conditions, along with a durability evaluation of the corresponding UHPC cylinders and FRP grid samples. Tensile retention strengths of UHPC and FRU plates were evaluated after exposure. Scanning electron microscope (SEM) analyses were employed to examine fracture surfaces. The results indicate that carbon FRP (CFRP) grids significantly enhanced the tensile performance of UHPC, showcasing improvements in tensile strength, multiple-cracking, and strain-hardening behaviors. Seawater exposure led to evident reductions in the tensile strength of UHPC plates, particularly those incorporating steel fibers. Conversely, FRU plates exhibited much smaller decreases, especially those reinforced with polyethylene (PE) fibers. This study highlights the suitability of FRU reinforced with PE fibers for marine infrastructures.

纤维增强聚合物（FRP）增强超高性能混凝土（UHPC）结构不仅解决了 FRP 增强普通混凝土结构刚度不足的问题，还为解决传统钢筋混凝土结构的耐久性难题提供了一种可行的解决方案。虽然一些研究探讨了 FRP 增强 UHPC（简称 FRU）的机械性能，但对其耐久性能仍未进行探讨。本文对含有钢纤维和聚乙烯（PE）纤维的 FRU 和 UHPC 板材进行了全面的耐久性评估，以比较它们在模拟海洋条件下的性能，同时还对相应的 UHPC 圆柱和 FRP 网格样本进行了耐久性评估。对 UHPC 板和 FRU 板暴露后的拉伸保持强度进行了评估。扫描电子显微镜（SEM）分析用于检查断裂表面。结果表明，碳玻璃纤维增强塑料（CFRP）网格显著提高了超高强度混凝土的拉伸性能，在拉伸强度、多重开裂和应变硬化行为方面均有改善。海水暴露明显降低了 UHPC 板材的抗拉强度，尤其是含有钢纤维的板材。相反，FRU 板材的下降幅度要小得多，特别是那些用聚乙烯（PE）纤维增强的板材。这项研究强调了用聚乙烯纤维增强的 FRU 适用于海洋基础设施。

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引用次数: 0

Modeling different modes of failure in reinforced concrete beams combining tensile and shear-frictional damage models and bond–slip coupling for non-matching reinforcement and fragmented concrete meshes 结合拉伸和剪切摩擦损伤模型以及非匹配钢筋和破碎混凝土网格的粘结滑移耦合，模拟钢筋混凝土梁的不同破坏模式

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-19 DOI: 10.1016/j.engstruct.2024.119265

Andrei F. Villa dos Santos, Marcela Gimenes, Eduardo Alexandre Rodrigues, Pedro R. Cleto, Osvaldo Luís Manzoli

A new strategy to predict the different failure processes of reinforced concrete members via macroscale modeling is proposed. In the mesh fragmentation framework , the technique relies on the use of condensed high aspect ratio interface elements and two independent damage models (tensile and shear-frictional), enabling specific energy dissipation for each fracture propagation mode, as well as modeling the formation and propagation of multiple fractures in the concrete. Additionally, to simulate reinforced concrete members, coupling finite elements are incorporated to model the interaction between the concrete and steel reinforcements, considering appropriate bond–slip behavior. Uniaxial compression tests are carried out to assess the ability of the strategy to predict the failure mechanism of concrete and to study the influence of material parameters such as cohesion and friction angle. The predictions of reinforced concrete beams with different spans, cross sections, and reinforcements are in good agreement with the experimental results reported in the literature, particularly with respect to the failure modes. The experimentally observed relationships between the geometric parameters and failure modes (flexural, shear and crushing failure modes) of reinforced concrete beams can also be properly predicted via the proposed approach.

本文提出了一种通过宏观建模预测钢筋混凝土构件不同破坏过程的新策略。在网格破碎框架中，该技术依赖于使用压缩的高纵横比界面元素和两个独立的破坏模型（拉伸和剪切摩擦），使每种断裂传播模式都有特定的能量消耗，并对混凝土中多条断裂的形成和传播进行建模。此外，为了模拟钢筋混凝土构件，还采用了耦合有限元来模拟混凝土与钢筋之间的相互作用，并考虑了适当的粘结滑移行为。通过单轴压缩试验来评估该策略预测混凝土破坏机制的能力，并研究内聚力和摩擦角等材料参数的影响。不同跨度、截面和配筋的钢筋混凝土梁的预测结果与文献报道的实验结果非常吻合，尤其是在破坏模式方面。实验观察到的钢筋混凝土梁几何参数与破坏模式（弯曲、剪切和挤压破坏模式）之间的关系也可以通过所提出的方法正确预测。

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引用次数: 0

Experimental study on bonded and unbonded prestressed precast concrete beamcolumn substructures under penultimate column removal 倒数第二根支柱拆除情况下有粘结和无粘结预应力预制混凝土梁柱下部结构的实验研究

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-19 DOI: 10.1016/j.engstruct.2024.119330

Hai-Rong Shi , Bin Zeng , Jun Yu , Chun-Lin Wang

The collapse resistance of prestressed precast concrete frames relies on the tie force of the strands, but the influence of the bond conditions and layout of the strands remains unclear. This study investigates these factors through push-down tests on four beamcolumn substructures under penultimate column removal: one reinforced concrete specimen and three precast specimens (unbonded prestressed, bonded prestressed, and bonded with low-prestress parabolic profile). The results revealed that, compared to the reinforced concrete specimen, the precast specimens exhibited similar performance but were uniformly weaker under compressive arch action. Under catenary action, the precast specimens demonstrated significantly greater ultimate deformation and load-bearing capacity. The unbonded prestressed specimen failed due to wire rupture, impairing the flexural resistance of all its joints. In the bonded prestressed specimen, the bonded strand mitigated this issue but fractured prematurely. The bonded low-prestress specimen achieved the highest deformation and load-bearing capacity due to the enhanced deformation capacity of the low-prestress strand.

预应力预制混凝土框架的抗倒塌能力取决于钢绞线的拉力，但钢绞线的粘结条件和布局的影响仍不清楚。本研究通过在倒数第二根柱子拆除的情况下对四个梁柱下部结构进行下压试验来研究这些因素：一个钢筋混凝土试件和三个预制试件（无粘结预应力、有粘结预应力和低应力抛物线粘结）。结果表明，与钢筋混凝土试样相比，预制试样表现出相似的性能，但在压缩拱作用下均较弱。在全缘作用下，预制试件的极限变形和承载能力明显更大。无粘结预应力试样因钢丝断裂而失效，损害了其所有接缝的抗弯能力。在有粘结预应力试样中，有粘结钢绞线缓解了这一问题，但过早断裂。由于低应力钢绞线的变形能力增强，有粘结低应力试样的变形和承载能力最高。

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引用次数: 0

A rcGAN-based surrogate model for nonlinear seismic response analysis and optimization of steel frames 基于 rcGAN 的代用模型，用于钢框架的非线性地震响应分析和优化

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-19 DOI: 10.1016/j.engstruct.2024.119199

Jiming Liu , Liping Duan , Yuheng Jiang , Lvcong Zhao , Jincheng Zhao

The combination of the surrogate model and optimization algorithm to solve structural optimization problems is an efficient way to lower computational costs and reduce time consumption. However, the development of surrogate models for structural analysis frequently faces challenges due to limited datasets. To tackle this issue, this paper presents a surrogate model capable of training on limited datasets while simultaneously predicting multiple concerned indicators, and demonstrates its effectiveness in performance assessment and design optimization through two seismic design case studies. Specifically, an improved model architecture based on the conditional Generative Adversarial Network (cGAN) is proposed. The feasibility of this surrogate model for seismic response analysis and optimization is initially demonstrated using an existing planar frame case. Subsequently, to validate the suitability of the surrogate model for Nonlinear Time History Analysis (NTHA) tasks, the proposed approach is applied to optimize a 3D steel frame equipped with nonlinear viscous dampers. Herein, a three-objective optimization problem is formulated, employing the Non-Dominated Sorting Genetic Algorithm (NSGA-II), driven by the trained rcGAN, to identify the Pareto front. The optimum design is subsequently selected from this front utilizing a multi-criteria decision-making technique. The outcomes from three optimization tests indicate that our approach effectively enhances the seismic performance of the frame while achieving substantial economic benefits, ultimately reducing the construction cost of the benchmark structure by up to 31.1 %.

结合代用模型和优化算法来解决结构优化问题是降低计算成本和减少时间消耗的有效方法。然而，由于数据集有限，结构分析代用模型的开发经常面临挑战。针对这一问题，本文提出了一种能够在有限数据集上进行训练，同时预测多个相关指标的代用模型，并通过两个抗震设计案例研究证明了其在性能评估和设计优化中的有效性。具体而言，本文提出了一种基于条件生成对抗网络（cGAN）的改进模型架构。利用现有的平面框架案例，初步证明了该代用模型在地震响应分析和优化方面的可行性。随后，为了验证代理模型在非线性时间历程分析（NTHA）任务中的适用性，提出的方法被应用于优化配备了非线性粘性阻尼器的三维钢框架。在此，利用非支配排序遗传算法 (NSGA-II)，在训练有素的 rcGAN 的驱动下，制定了一个三目标优化问题，以识别帕累托前沿。随后，利用多标准决策技术从该前沿选择最佳设计。三次优化测试的结果表明，我们的方法有效地提高了框架的抗震性能，同时实现了巨大的经济效益，最终将基准结构的建造成本降低了 31.1%。

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引用次数: 0

Buffeting induced fatigue damage assessment of long-span bridge decks under uncertain turbulence conditions 不确定湍流条件下大跨度桥面的缓冲诱发疲劳损伤评估

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-19 DOI: 10.1016/j.engstruct.2024.119292

Zubair Zahoor Banday , Aksel Fenerci , Tor Martin Lystad , Ole Andre Øiseth

Fatigue in wind-sensitive structures is influenced by the mean wind speed and the turbulence characteristics. This study investigates the importance of uncertainty in the turbulence characteristics of buffeting-induced fatigue damage of flexible wind-sensitive structures, focusing on long-span bridges. We address the importance of the variability of uncertainty in the wind field by using a probabilistic wind field model, including uncertain turbulence parameters for calculating the accumulated fatigue damage throughout the structure’s design life. However, it has been demonstrated that a high computational load accompanies this approach. A new method is proposed that significantly reduces the computational effort through surrogate modelling. This is achieved through a sequentially updating Gaussian Process surrogate modelling approach, which integrates new simulation points into the training dataset and reduces the number of buffeting calculations required for the surrogate to converge to the true solution, thereby reducing the computational cost by almost 95%. The efficiency of the algorithm is demonstrated by using it to compute the fatigue damage accumulation through the design life for a long-span bridge girder, resulting in the increase of damage by several orders of magnitude in comparison to the conventional method of treating the turbulence parameters as deterministic and uncorrelated.

风敏结构的疲劳受平均风速和湍流特性的影响。本研究以大跨度桥梁为重点，探讨了湍流特性的不确定性对柔性风敏结构缓冲诱发疲劳损伤的重要性。我们通过使用概率风场模型，包括不确定的湍流参数来计算整个结构设计寿命期间的累积疲劳损伤，从而解决了风场中不确定性变化的重要性问题。然而，事实证明这种方法的计算负荷很高。本文提出了一种新方法，通过代理建模大大减少了计算量。这是通过一种顺序更新的高斯过程代理建模方法实现的，该方法将新的模拟点整合到训练数据集中，减少了代理收敛到真实解决方案所需的缓冲计算次数，从而将计算成本降低了近 95%。与将湍流参数视为确定性和非相关性的传统方法相比，该算法在计算大跨度桥梁梁设计寿命期间的疲劳损伤累积时，损伤程度增加了几个数量级，从而证明了该算法的效率。

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引用次数: 0

An accurate and ready-to-use approach for the estimation of impedance functions of regular pile groups for offshore wind turbine foundations. Vertical and rocking components 用于估算海上风力涡轮机地基的规则桩群阻抗函数的准确且随时可用的方法。垂直和摇摆部分

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2024-11-18 DOI: 10.1016/j.engstruct.2024.119288

Eduardo Rodríguez-Galván, Guillermo M. Álamo, Juan J. Aznárez, Orlando Maeso

The interaction factor superposition method in the determination of the vertical and rocking impedances of pile groups for jacket-supported Offshore Wind Turbines is studied. The vertical and rocking group dynamic impedances obtained by this method are compared with those computed by a previously developed continuum model. The influence of the main parameters that define the problem is also studied. In order to propose an alternative calculation solution, some expressions dependent of these parameters are fitted from an extensive selection of jacket pile group configurations. These expressions allow to estimate the vertical flexibility of the source pile and the interaction factor between a pair of piles. Subsequently, applying elastic superposition, the group impedance functions are determined. Results show that the interaction factor superposition method correctly reproduces the vertical and rocking group dynamic impedances. Therefore, for these regular pile groups with large spacing ratios, the assumption of only considering the direct interaction between pile pairs leads to accurate results. Results obtained with the proposed fitted expressions generally conduct to a good estimation, properly reproducing the variation produced by the influence of the different parameters. Thus, this superposition method and the proposed expressions can be employed to quickly and simply reproduce the vertical soil–structure interaction of this type of structures.

研究了确定护套支撑海上风力涡轮机桩群垂直和摇摆阻抗的相互作用因子叠加法。将该方法获得的垂直和摇摆群动阻抗与之前开发的连续体模型计算的结果进行了比较。此外，还研究了定义问题的主要参数的影响。为了提出一种替代计算方案，从大量的护筒桩群配置中选择了一些与这些参数相关的表达式进行拟合。通过这些表达式，可以估算源桩的垂直弹性和一对桩之间的相互作用系数。随后，应用弹性叠加法确定群阻抗函数。结果表明，相互作用系数叠加法正确地再现了垂直和摇摆群动阻抗。因此，对于这些具有较大间距比的规则桩群，仅考虑桩对之间直接相互作用的假设可得出准确的结果。使用所提出的拟合表达式得出的结果一般都能进行良好的估算，正确再现不同参数影响所产生的变化。因此，这种叠加方法和建议的表达式可用于快速、简单地再现此类结构的垂直土-结构相互作用。

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引用次数: 0