Computers & Structures最新文献_第3页

Multi-population competition genetic algorithm for assessing long-span cable-supported bridge girder’s maximum deflections and rotation angles under live loads: A direct optimization task solution 多群体竞争遗传算法用于评估大跨度斜拉桥梁在活载荷作用下的最大挠度和旋转角度：直接优化任务解决方案

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-28 DOI: 10.1016/j.compstruc.2024.107576

Han-xu Zou, Wen-ming Zhang, Yu-peng Chen

This study addresses the stability problem of long-span cable-supported bridges (CSBs) under live loads, which requires an accurate estimation of maximum girder deflection and rotation angle. In contrast to the cumbersome influence line method or analytical method, which ignores the structural nonlinearity of this bridge type or uses too many constraint conditions, we convert this problem into an optimization task. Since the number of segments of distributed live loads under which maximum girder deflection and rotation angle occur (i.e., the number of optimization variables) is unknown due to CSB’s structural complexity, a multi-population competition genetic algorithm (MPCGA), inspired by the population competition theory in ecology, is applied. It incorporates the Lotka-Volterra competition model to depict the changing sizes of the competing populations. We designed the interspecies migration and exchange mechanism for the above engineering problem and ran ANSYS to compute individual fitness. This algorithm offers high accuracy and efficiency in solving the maximum girder deflection and rotation angle of the long-span CSB, the positions where the maximum girder deflection and rotation angle occur, and the corresponding live load patterns. Finally, the proposed method is validated by a case study of a hybrid CSB with a main span of 1400 m. The calculation results obtained via the conventional influence line and proposed methods are compared, proving the latter’s supremacy.

本研究探讨了大跨度斜拉桥（CSB）在活荷载作用下的稳定性问题，这需要对最大梁挠度和旋转角进行精确估算。与繁琐的影响线法或分析法相比，我们将这一问题转化为优化任务，因为影响线法或分析法忽视了这种桥梁类型的结构非线性，或使用了太多的约束条件。由于 CSB 结构的复杂性，出现最大梁体挠度和旋转角度的分布式活载的节段数量（即优化变量的数量）是未知的，因此我们采用了多种群竞争遗传算法 (MPCGA)，其灵感来自生态学中的种群竞争理论。它采用 Lotka-Volterra 竞争模型来描述竞争种群规模的变化。我们为上述工程问题设计了种间迁移和交换机制，并运行 ANSYS 计算个体适应度。该算法在求解大跨度 CSB 的最大大梁挠度和旋转角度、最大大梁挠度和旋转角度出现的位置以及相应的活载荷模式方面具有较高的准确性和效率。最后，通过对主跨为 1400 米的混合式 CSB 进行案例研究，对所提出的方法进行了验证。通过比较传统影响线法和所提出方法的计算结果，证明了后者的优越性。

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引用次数: 0

A frequency-independent absorption function surrogate for perfectly matched layer in exterior acoustics 与频率无关的吸收函数替代物，用于室外声学中的完全匹配层

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-25 DOI: 10.1016/j.compstruc.2024.107569

Xiang Xie , Haijun Wu , Steffen Marburg

In many engineering applications, the solution of acoustic wave problems in the infinite domain is required over a broad frequency range with densely sampled increments. In order to achieve efficient numerical simulations via a spatial discretization, e.g. finite element method, additional artificial absorbing boundaries are necessary to truncate the computational domain into appropriate bounded sizes. One of the most commonly used non-reflecting techniques to attenuate propagating waves is known as the perfectly matched layer. However, the system matrices arising from the finite element treatment of the Helmholtz equation in the absorbing layers are frequency-dependent, implying that they must be formed and inverted at each frequency of interest. Such a procedure is rather troublesome for frequency sweeps. To address this, a surrogate of perfectly matched layers is proposed, which enables the corresponding system matrices to be independent of the frequency. Moreover, it avoids the use of a relatively large computational domain and relatively thick enclosed layers at low frequencies, thus improving the ability of perfectly matched layers across the entire frequency range. After that, an adaptive projection-based model order reduction scheme is further developed to reduce the computational complexity of exterior acoustic systems. A robust error indicator based on the relative error of two constructed reduced order models is accordingly introduced. The performance of the present solution framework is discussed and compared with other implementation strategies, in the context of multi-frequency solution of two-dimensional test models with single or multiple scatterers.

在许多工程应用中，需要在宽广的频率范围内以密集的采样增量解决无限域中的声波问题。为了通过空间离散化（如有限元法）实现高效的数值模拟，有必要增加人工吸收边界，将计算域截断为适当的有界尺寸。最常用的衰减传播波的非反射技术之一是完全匹配层。然而，吸收层中亥姆霍兹方程的有限元处理所产生的系统矩阵与频率有关，这意味着必须在每个感兴趣的频率上形成和反转这些矩阵。这样的程序对于频率扫描来说相当麻烦。为了解决这个问题，我们提出了一种完全匹配层的替代方法，它能使相应的系统矩阵与频率无关。此外，它还避免了在低频时使用相对较大的计算域和相对较厚的封闭层，从而提高了完全匹配层在整个频率范围内的能力。之后，进一步开发了一种基于投影的自适应模型阶次缩减方案，以降低外部声学系统的计算复杂度。相应地，还引入了一种基于两个已构建缩减阶次模型相对误差的稳健误差指标。在对具有单散射体或多散射体的二维测试模型进行多频率求解时，讨论了本求解框架的性能，并与其他实施策略进行了比较。

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引用次数: 0

Automatic yield-line analysis of out-of-plane loaded masonry cladding panels 平面外荷载砌体覆面板的自动屈服线分析

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-23 DOI: 10.1016/j.compstruc.2024.107563

Nicola Grillanda , Linwei He , Matthew Gilbert , Colin C. Smith

To design out-of-plane loaded masonry cladding panels, as well as modern non-loadbearing masonry panels, the yield-line method has become widely used by engineers, and features in various design codes. However, the traditional hand-based yield-line analysis method can be challenging to apply to complex or irregular shapes, since the form of the critical yield-line pattern will generally not be known in advance. The discontinuity layout optimization (DLO) procedure, previously applied to reinforced concrete slabs, is here extended to treat masonry wall panels, with (i) the flexural moment capacity modified to take account of vertical dead loads from above; and (ii) shear failure also modelled, if critical (e.g., at damp proof course level). A key benefit of DLO is that the critical yield-line pattern can be identified automatically, with a rigorous linear programming-based formulation employed to ensure that a globally optimal solution is obtained for any given numerical discretization. Given the power of modern desktop PCs, this effectively eliminates the possibility of the critical yield-line failure mechanism being missed, allowing the presented method to be applied with confidence to both regular and complex-shaped masonry panels. A range of examples are used to demonstrate the efficacy of the approach, with solutions compared with those from analytical models and experimental tests.

在设计平面外荷载砌体覆面板以及现代非承重砌体面板时，屈服线方法已被工程师广泛采用，并成为各种设计规范的特色。然而，传统的手工屈服线分析方法很难应用于复杂或不规则的形状，因为临界屈服线模式的形式通常无法预先知道。以前应用于钢筋混凝土板的不连续布局优化（DLO）程序，在此被扩展用于处理砌体墙板，(i) 弯曲弯矩能力被修改，以考虑来自上方的垂直死荷载；(ii) 剪切破坏也被模拟，如果临界的话（例如在防潮层）。DLO 的一个主要优点是可以自动识别临界屈服线模式，并采用严格的线性规划方法，确保在任何给定的数值离散化条件下都能获得全局最优解。鉴于现代台式 PC 的强大功能，这有效地消除了遗漏关键屈服线失效机制的可能性，从而使所介绍的方法可以放心地应用于规则和复杂形状的砌体面板。我们使用了一系列实例来证明该方法的有效性，并将解决方案与分析模型和实验测试进行了比较。

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引用次数: 0

3D limit analysis of reinforced concrete with sliding along smeared cracks 钢筋混凝土沿抹灰裂缝滑动的三维极限分析

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-18 DOI: 10.1016/j.compstruc.2024.107561

Agnès Fliscounakis , Mathieu Arquier , Mohammed-Khalil Ferradi

Limit analysis (LA) is successfully used for investigating the bearing capacity of reinforced concrete (RC) structures. Some cautions must be taken when using this method for RC since the concrete component exhibits a softening behavior with decreasing strength and limited ductility. A commonly adopted provision consists of considering isotropic reduced values of concrete strength to be input in the analysis (empirical effectiveness factors). In this paper, an alternative and completely new approach is proposed and investigated in which concrete strength is weakened in a more targeted manner. To that purpose, the commonly used 3D truncated Mohr-Coulomb (TMC) criterion is adopted to classically describe the compressive, tensile, and shear failure of concrete. However, TMC is here in an original way enriched by additional constraints that allow to account for weakness and anisotropy induced by preferential failure patterns, assumed a priori. The limit analysis approach is then formulated for two dual analyses in the convex optimization framework, making it possible to quantify the numerical error and obtain a lower and an upper bound of the limit load. Numerical examples illustrate the agreement of the formulation with academic results and laboratory tests.

极限分析法（LA）被成功地用于研究钢筋混凝土（RC）结构的承载能力。在对 RC 结构使用这种方法时必须注意一些问题，因为混凝土构件会随着强度的降低和延展性的限制而表现出软化行为。通常采用的一种方法是在分析中输入混凝土强度的各向同性降低值（经验有效系数）。本文提出并研究了一种全新的替代方法，即以更有针对性的方式削弱混凝土强度。为此，本文采用了常用的三维截断莫尔-库仑（TMC）准则来描述混凝土的抗压、抗拉和抗剪破坏。然而，TMC 在这里以一种新颖的方式被附加的约束条件所丰富，这些约束条件允许考虑先验假定的优先破坏模式所引起的弱点和各向异性。极限分析方法是在凸优化框架下进行的两种双重分析，因此可以量化数值误差，并获得极限荷载的下限和上限。数值示例说明了该公式与学术成果和实验室测试的一致性。

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引用次数: 0

Adaptive isogeometric topology optimization of shell structures based on PHT-splines 基于 PHT-样条线的壳体结构自适应等值拓扑优化

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-17 DOI: 10.1016/j.compstruc.2024.107565

Zepeng Wen , Qiong Pan , Xiaoya Zhai , Hongmei Kang , Falai Chen

This paper proposes an adaptive isogeometric topology optimization framework for shell structures by utilizing a continuous density field represented as Polynomial splines over Hierarchical T-meshes (PHT-splines). This framework ensures an exact representation of shell structures, eliminating the geometric inaccuracies commonly associated with topology optimization. In the meanwhile, the meshes used for design and analysis are refined adaptively and locally along the density boundary to achieve a smooth material layout with reduced degrees of freedom (DOF). The adaptive sensitivity filter is tailored to the characteristics of PHT-splines, where the filter radius is determined automatically and adaptively, without the need to specify parameters in advance. Numerical experiments conducted on various shell structures validate the efficacy of the proposed adaptive framework. In comparison with isogeometric topology optimization based on non-adaptive cases (i.e. B-splines), the proposed adaptive framework demonstrates a notable enhancement in computational efficiency, with a

50 % - 80 %

reduction in running time and a

30 % - 60 %

reduction in DOF. Additionally, we offer a detailed comparison between PHT-splines and other locally refinable splines in the context of shell topology optimization. Numerical experiments exhibit that the efficient and localized refinement capability of PHT-splines provides advantages in both computational efficiency and structural performance for topology optimization.

本文提出了一种针对壳体结构的自适应等距拓扑优化框架，利用分层 T 型网格上的多项式样条（PHT-样条）来表示连续密度场。该框架确保了壳结构的精确表示，消除了拓扑优化中常见的几何误差。同时，用于设计和分析的网格会沿着密度边界自适应地局部细化，以实现平滑的材料布局，减少自由度（DOF）。自适应灵敏度滤波器是根据 PHT-样条曲线的特性量身定制的，滤波器半径是自动自适应确定的，无需事先指定参数。在各种壳体结构上进行的数值实验验证了所提出的自适应框架的有效性。与基于非自适应情况（即 B-样条曲线）的等几何拓扑优化相比，所提出的自适应框架显著提高了计算效率，运行时间减少了 50%-80%，DOF 减少了 30%-60%。此外，我们还详细比较了 PHT 样条曲线和其他局部可细化样条曲线在壳体拓扑优化中的应用。数值实验表明，PHT 样条的高效局部细化能力为拓扑优化提供了计算效率和结构性能方面的优势。

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引用次数: 0

Isogeometric topology optimization method for design with local stress constraints 针对局部应力约束设计的等几何拓扑优化方法

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-16 DOI: 10.1016/j.compstruc.2024.107564

Zhao Fan , Liang Gao , Hao Li

Engineering structures are required to meet strength conditions to ensure engineering safety, where the maximum stress level of the structure mainly characterizes the structural strength. This study proposes an isogeometric topology optimization method for the local stress-constrained design. This method establishes an optimization model with volume fraction as the objective function and maximum von Mises stress as the constraint condition. The augmented lagrangian approach is introduced to ensure that the design results satisfy stress constraints locally. To increase the convergence rate of stress-constrained topology optimization, we develop a new stress constraint function, and compare it with the other two stress constraint functions proposed by previous research. Sensitivity analysis of the local stress-constraint and volume objective based on an isogeometric topology optimization framework is systematically derived. The design result is compared with the traditional global stress minimization design through typical numerical examples. In addition, this method is extended to the three-dimensional stress-constrained topology optimization design problem that has rarely been studied in the isogeometric-analysis-based topology optimization framework. Several typical numerical examples are presented to demonstrate the method’s effectiveness. It demonstrates that the proposed method inherits the merits of the exact geometry and high-order continuity between elements of isogeometric analysis and can effectively control the maximum von Mises stress level of structures, with a faster convergence rate.

工程结构需要满足强度条件以确保工程安全，其中结构的最大应力水平主要表征结构强度。本研究提出了一种局部应力约束设计的等几何拓扑优化方法。该方法建立了一个以体积分数为目标函数、以最大 von Mises 应力为约束条件的优化模型。为确保设计结果满足局部应力约束，引入了增强拉格朗日方法。为了提高应力约束拓扑优化的收敛速度，我们开发了一种新的应力约束函数，并将其与之前研究中提出的其他两种应力约束函数进行了比较。基于等几何拓扑优化框架，系统地得出了局部应力约束和体积目标的敏感性分析。通过典型的数值实例，将设计结果与传统的全局应力最小化设计进行了比较。此外，该方法还扩展到了基于等几何分析拓扑优化框架的三维应力约束拓扑优化设计问题，而该问题在等几何分析拓扑优化框架中鲜有研究。本文列举了几个典型的数值实例来证明该方法的有效性。结果表明，所提方法继承了等几何分析的精确几何和元素间高阶连续性的优点，能有效控制结构的最大 von Mises 应力水平，且收敛速度更快。

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引用次数: 0

An implicit gradient-enhanced microplane damage material model in the coupled implicit MPM-FEM 耦合隐式 MPM-FEM 中的隐式梯度增强微平面损伤材料模型

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-13 DOI: 10.1016/j.compstruc.2024.107559

Osvaldo Andres Oropeza-Navarro, Ahmad Chihadeh, Jakob Platen, Michael Kaliske

The contribution at hand introduces a novel formulation that couples the Material Point Method (MPM) and Finite Element Method (FEM) based on nonlocal mechanics using an implicit time integration scheme. A constitutive formulation at finite deformations to describe fiber-reinforced concrete is applied. A damage approach within the microplane framework is utilized to capture the induced anisotropy in concrete structures. Furthermore, the microplane model is able to capture the initial anisotropy due to fiber inclusion. In addition, an implicit gradient enhancement is utilized to overcome problems of numerical instabilities when modeling softening phenomena. Numerical examples are presented to demonstrate the capability of this new approach to couple the mechanical and nonlocal fields between MPM and FEM in a reliable and physical manner.

本文采用隐式时间积分方案，在非局部力学的基础上将材料点法（MPM）和有限元法（FEM）结合起来，提出了一种新颖的计算方法。该方法采用有限变形的构成公式来描述纤维增强混凝土。利用微平面框架内的损伤方法来捕捉混凝土结构中的诱导各向异性。此外，微平面模型还能捕捉到纤维夹杂导致的初始各向异性。此外，在对软化现象建模时，利用隐式梯度增强来克服数值不稳定性问题。本报告提供了一些数值示例，以证明这一新方法能够以可靠的物理方式将 MPM 和 FEM 之间的机械场和非局部场耦合起来。

引用次数: 0

Adaptive isogeometric gear contact analysis: Geometry generation, truncated hierarchical B-Spline refinement and validation 自适应等距齿轮接触分析：几何生成、截断分层 B 样条细化和验证

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-13 DOI: 10.1016/j.compstruc.2024.107553

Christos Karampatzakis , Angelos Mantzaflaris , Christopher Provatidis , Athanassios Mihailidis

Gears are one of the most widely used transmission components. Their operation relies on the contact between mating gear teeth flanks for the transmission of power. Accurate prediction of the contact stresses at these regions, is crucial for the design and dimensioning of these systems. Gear design is centered around highly smooth involute curves that greatly influence their contact behaviour. In this paper, a fully adaptive isogeometric contact modelling scheme, based on hierarchical splines, is presented and applied to the simulation of gear contact problems. In particular, isogeometric simulation is performed for the modelling of mating pair of gear teeth, regarded as linearly elastic bodies. A boundary fitted B-Spline representation of the teeth is automatically generated from engineering design parameters and is used to define the initial discretisation basis. The numerical integration over the contact region is addressed using the so called, Gauss-Point to Surface formulation and a closest point projection procedure. Truncated hierarchical B-Splines are used to capture the highly localised nature of contact, while effectively reducing the number of degrees of freedom. The adaptivity is driven by the strain energy density gradient, which allows to automatically localise the mesh without a priori knowledge of the contact region between the teeth flanks. In our experiments we justify the choices made in different steps of our algorithm and we assess the performance of our adaptive solver with respect to classical tensor product B-Splines.

齿轮是应用最广泛的传动部件之一。它们的运行依赖于配合齿轮齿面之间的接触来传递动力。准确预测这些区域的接触应力对于这些系统的设计和尺寸确定至关重要。齿轮设计以高度平滑的渐开线曲线为中心，而渐开线曲线对齿轮的接触性能有很大影响。本文介绍了一种基于分层样条的完全自适应等距接触建模方案，并将其应用于模拟齿轮接触问题。特别是，将一对啮合的齿轮齿视为线性弹性体，对其进行等距模拟建模。根据工程设计参数自动生成齿轮的边界拟合 B-Spline 表示，并用于定义初始离散化基础。使用所谓的高斯点到面公式和最近点投影程序对接触区域进行数值积分。截断分层 B-样条曲线用于捕捉接触的高度局部性，同时有效减少自由度数量。自适应能力由应变能量密度梯度驱动，它允许在不预先了解齿面接触区域的情况下自动定位网格。在实验中，我们对算法不同步骤中的选择进行了论证，并评估了自适应求解器与传统张量乘积 B-样条曲线的性能。

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引用次数: 0

Efficient approaches for modeling and simulating the mechanical behavior of concrete using lattice discrete particle models 利用晶格离散粒子模型建模和模拟混凝土力学行为的高效方法

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-09 DOI: 10.1016/j.compstruc.2024.107557

Jiajia Wang , Jan Vorel , Wouter Botte , Daniele Pelessone , Roman Wan-Wendner

Simulating the quasi-static mechanical behavior of concrete at the micro- or meso-scale, considering its heterogeneous nature, quickly becomes impractical in terms of computational cost. This manuscript explores efficient computational strategies in numerical modeling by means of the Lattice Discrete Particle Model (LDPM), a state-of-the-art approach for simulating concrete at the coarse aggregate level, emphasizing three interaction approaches. Whereas the original formulation of LDPM employs a 12-facet formulation, this research proposes a simplified interaction approach for LDPM, based on either 6-facet or edge-based interactions, designed to significantly reduce computational costs while maintaining precise predictions of the concrete fracture behavior. This approach is systematically applied to a variety of standard concrete tests, including unconfined compression, biaxial compression, triaxial compression, torsional-compressive, three-point bending, and cyclic compression loading in order to assess the predictive capabilities of the model. The efficiency and accuracy of the reduced number of interaction surfaces are critically discussed in both tensile and compressive loading conditions. The results indicate that approaches based on edge-based and 6-facet interactions substantially reduce computational costs and memory usage while providing similar results to the 12-facet model, except for unconfined compression simulations based on edge-based interaction. This research opens a promising avenue for advancing the utilization of LDPM in concrete mechanics simulations.

考虑到混凝土的异质性，在微观或中观尺度上模拟混凝土的准静态力学行为在计算成本方面很快变得不切实际。本手稿通过晶格离散粒子模型（LDPM）探讨了数值建模中的高效计算策略，LDPM 是模拟粗骨料级混凝土的最先进方法，强调了三种相互作用方法。LDPM 的原始配方采用 12 面配方，而本研究提出了一种基于 6 面或基于边缘的 LDPM 简化交互方法，旨在显著降低计算成本，同时保持对混凝土断裂行为的精确预测。该方法被系统地应用于各种标准混凝土试验，包括无约束压缩、双轴压缩、三轴压缩、扭转压缩、三点弯曲和循环压缩加载，以评估模型的预测能力。在拉伸和压缩加载条件下，对减少相互作用面数量的效率和准确性进行了认真讨论。结果表明，基于边缘和 6 面相互作用的方法大大降低了计算成本和内存使用量，同时提供了与 12 面模型相似的结果，但基于边缘相互作用的非约束压缩模拟除外。这项研究为推进 LDPM 在混凝土力学模拟中的应用开辟了一条前景广阔的道路。

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引用次数: 0

An efficient method for estimating building dynamic response due to train operations in tunnel considering transmission path from source to receiver 考虑到从源头到接收器的传输路径，估算隧道内列车运行引起的建筑物动态响应的有效方法

IF 4.4 2区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Structures

Pub Date : 2024-10-09 DOI: 10.1016/j.compstruc.2024.107555

Chao Zou , Xuming Li , Chao He , Shunhua Zhou

The paper presents an efficient method for estimating the dynamic response of buildings due to train operations in tunnel. The proposed method involves four models to consider the transmission path in the train-track-tunnel-soil-pile-building chain: the vehicle model, track-tunnel-soil model, building model, and soil-structure interaction model. A series of theoretical methods are employed, including the multibody dynamic method for wheel-rail interaction, the double Euler-Bernoulli beam method for track structures, the wave decomposition method and transfer matrix method for vibration propagation in soil, the impedance method for building vibration transmission. Validation is conducted through measurements of train-induced ground-borne vibrations and building vibrations in Guangzhou, China. The estimated vibrations demonstrated good agreement with measured vibrations, indicating the feasibility of the proposed method. Parametric studies are subsequently conducted to investigate the influence of spatial relationships between tunnel and pile on building vibrations. The presence of piles results in dissipation and attenuation of vibration energy due to the kinematic interaction. The spatial distribution of the wave field within the soil can significantly impact the coupling loss between the soil and structure. The research findings facilitate a clear comprehension of vibration transmission mechanisms from source to receiver, which are readily applicable in engineering practice for engineers.

本文提出了一种估算隧道内列车运行对建筑物动态响应的有效方法。所提出的方法涉及四个模型，以考虑火车-轨道-隧道-土壤-桩基-建筑物链中的传递路径：车辆模型、轨道-隧道-土壤模型、建筑物模型和土壤-结构相互作用模型。采用了一系列理论方法，包括轮轨相互作用的多体动力学方法、轨道结构的双欧拉-伯努利梁法、土壤振动传播的波分解法和传递矩阵法、建筑物振动传播的阻抗法。通过在中国广州测量列车引起的地面振动和建筑物振动进行了验证。估算的振动值与测量的振动值显示出良好的一致性，表明了所提方法的可行性。随后进行了参数研究，以探讨隧道和桩基之间的空间关系对建筑物振动的影响。由于运动相互作用，桩的存在会导致振动能量的耗散和衰减。土壤中波场的空间分布会对土壤和结构之间的耦合损失产生重大影响。这些研究成果有助于清楚地理解从振动源到振动接收器的振动传播机制，便于工程师在工程实践中应用。

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引用次数: 0