Soil Dynamics and Earthquake Engineering最新文献

Evaluation of the static and dynamic behavior characteristics of biopolymer-treated soil at varying moisture contents 评估经生物聚合物处理的土壤在不同含水量下的静态和动态特性

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-15 DOI: 10.1016/j.soildyn.2024.109080

Chaewoon Jang , Beomjoo Yang , Won-Taek Hong , Jongwon Jung

Cement is widely used for ground strengthening; however, such applications have several adverse environmental effects, including increased carbon dioxide emissions and groundwater contamination. With a global focus on eco-friendliness, there is growing interest in the development of alternative ground strengthening materials. Biopolymers, which can be extracted from nature, are particularly suitable materials for this purpose owing to their ability to enhance the soil strength. Consequently, research based on ground strengthening using biopolymers is ongoing. However, few studies have been conducted on the water resistance properties and liquefaction resistance strengths of biopolymer-treated soils. Therefore, in this study, the strength changes and water resistance characteristics of soils treated with agar gum, gellan gum, and xanthan gum were evaluated at different moisture contents by means of unconfined compression tests. Furthermore, the liquefaction resistance strengths of the saturated biopolymer-treated soils were analyzed using cyclic triaxial tests. The results confirmed that the compressive strengths of the agar-gum-, gellan-gum-, and xanthan-gum-treated soils were affected by the final moisture content, regardless of the curing time. Moreover, the compressive strength of the submerged cured biopolymer-treated soils and the liquefaction resistance were compared and analyzed, demonstrating that agar-gum-, and gellan-gum-treated soils exhibit water resistance.

水泥被广泛用于地基加固，但这种应用会对环境造成一些不利影响，包括增加二氧化碳排放和地下水污染。随着全球对环保的重视，人们对开发替代性地基加固材料的兴趣日益浓厚。生物聚合物可从自然界中提取，具有增强土壤强度的能力，是特别适用于这一目的的材料。因此，利用生物聚合物加固地面的研究正在进行中。然而，关于生物聚合物处理过的土壤的抗水性能和抗液化强度的研究却很少。因此，在本研究中，通过无约束压缩试验评估了使用琼脂胶、结冷胶和黄原胶处理的土壤在不同含水量下的强度变化和抗水特性。此外，还通过循环三轴试验分析了饱和生物聚合物处理土壤的抗液化强度。结果证实，无论固化时间长短，琼脂胶、结冷胶和黄原胶处理过的土壤的抗压强度都会受到最终含水量的影响。此外，还对浸水固化的生物聚合物处理土的抗压强度和抗液化性能进行了比较和分析，结果表明琼脂胶和结冷胶处理土具有耐水性。

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引用次数: 0

Investigation of dynamic responses of slopes in various anchor cable failure modes 各种锚索失效模式下的斜坡动态响应研究

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-14 DOI: 10.1016/j.soildyn.2024.109077

Xing Gao , Jinqing Jia , Xiaohua Bao , Guoxiong Mei , Lihua Zhang , Bingxiong Tu

To clarify the effect of various anchor cable failure modes on the dynamic responses of slopes, the FLAC3D software was redeveloped. Constitutive models of cable elements in different anchor cable failure modes were proposed and embedded into the main program of slope dynamic calculation. The axial force, acceleration, and displacement responses in different anchor cable failure modes were compared and analyzed. The effects of seismic parameters on the anchor cable failure modes were also investigated. A matching relationship between the ultimate load-bearing capacities of the anchorage, anchoring interface, and tendon was proposed. The results reveal that the seismic intensity causing anchor cable damage in anchorage failure mode (AFM) and grouting body failure mode is 0.2g–0.3 g lower than that in tendon failure mode. At the moment of failure, the stress released by the anchor cable in AFM is the highest, with the most evident instantaneous slope acceleration fluctuation. In the collaborative seismic design of the anchorage, anchoring section, and anchor tendon, the ultimate load-bearing capacities of the anchorage and anchoring interface should be increased by 1.8 times to match the tensile bearing capacity of the tendon. This study provides a reference for the seismic anchorage design of slopes and offers suggestions for selecting seismic design parameters for anchor cables.

为明确各种锚索破坏模式对边坡动力响应的影响，重新开发了 FLAC3D 软件。提出了不同锚索破坏模式下的索元构造模型，并将其嵌入到边坡动力计算主程序中。对比分析了不同锚索破坏模式下的轴力、加速度和位移响应。同时还研究了地震参数对锚索破坏模式的影响。提出了锚具、锚固界面和锚索极限承载力之间的匹配关系。结果表明，在锚碇破坏模式（AFM）和灌浆体破坏模式下，导致锚索破坏的地震烈度比在筋破坏模式下低 0.2g-0.3 g。在破坏瞬间，锚索在锚碇破坏模式下释放的应力最大，瞬时边坡加速度波动最明显。在锚具、锚固段和锚索的协同抗震设计中，锚具和锚固界面的极限承载力应提高 1.8 倍，以匹配锚索的抗拉承载力。本研究为斜坡抗震锚固设计提供了参考，并为锚索抗震设计参数的选择提供了建议。

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引用次数: 0

Knowledge structure and research progress in earthquake-induced liquefaction assessment from 2000 to 2023: A scientometric analysis incorporating domain knowledge 2000 年至 2023 年地震诱发液化评估的知识结构和研究进展：纳入领域知识的科学计量分析

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-14 DOI: 10.1016/j.soildyn.2024.109075

Hongning Qi , Jian Zhou , Kang Peng , Manoj Khandelwal

Earthquake-induced liquefaction is a severe geological hazard that poses substantial risks to human safety making its evaluation critical. Despite prolonged discussions in academia and engineering, contemporary literature on earthquake-induced liquefaction assessment primarily focuses on specific methodologies, lacking a comprehensive overviews. This study systematically analyzed 824 research publications on earthquake-induced liquefaction assessment spanning from 2000 to 2023 within the Web of Science Core Collection (WoSCC) utilizing bibliometric approaches, including Citespace and VOSviewer. The primary objective was to meticulously analyze and explore the earthquake-induced liquefaction assessment field through bibliometric methods. The analysis reveals a steady increase in research output, transitioning from foundational theoretical development to advanced methodological innovations. Furthermore, a complete understanding of the research dynamics in this domain has been established by analyzing the publication trends, collaborative networks across journals, countries, institutions, and authors, and the evolution of significant research themes. Additionally, various techniques employed for earthquake-induced liquefaction assessment, including in-situ experiments, earthquake energy methodologies, numerical modeling approaches, and artificial intelligence methods, were explored, elucidating their characteristics and limitations. Finally, this study synthesizes the advancements and trends in earthquake-induced liquefaction assessment over recent decades, while also considering future research directions. It offers valuable insights into the methodologies for assessing earthquake-induced liquefaction and outlines potential avenues for future exploration.

地震诱发的液化是一种严重的地质灾害，对人类安全构成巨大风险，因此对其进行评估至关重要。尽管学术界和工程界对地震诱发液化评估进行了长期讨论，但当代有关地震诱发液化评估的文献主要集中在具体方法上，缺乏全面概述。本研究利用 Citespace 和 VOSviewer 等文献计量学方法，系统分析了 Web of Science Core Collection（WoSCC）中有关地震诱发液化评估的 824 篇研究出版物，时间跨度从 2000 年到 2023 年。主要目的是通过文献计量学方法对地震诱发液化评估领域进行细致的分析和探索。分析结果显示，研究成果稳步增长，从基础理论发展过渡到先进的方法创新。此外，通过分析发表趋势、期刊、国家、机构和作者之间的合作网络以及重要研究主题的演变，全面了解了该领域的研究动态。此外，还探讨了地震诱发液化评估所采用的各种技术，包括现场实验、地震能量方法、数值建模方法和人工智能方法，并阐明了这些技术的特点和局限性。最后，本研究总结了近几十年来地震诱发液化评估的进展和趋势，同时也考虑了未来的研究方向。它为评估地震诱发液化的方法提供了宝贵的见解，并概述了未来探索的潜在途径。

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引用次数: 0

A novel physics-constrained neural network: An illustration of ground motion models 新型物理约束神经网络：地面运动模型说明

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-14 DOI: 10.1016/j.soildyn.2024.109071

Duofa Ji , Chenxi Li , Changhai Zhai , You Dong

Ground motion model (GMM) is essential for seismic hazard analysis and can be developed using either empirical or machine learning approaches. The former often results in suboptimal predictive performance, and the latter frequently faces challenges related to interpretability and explainability although providing more accurate results. To overcome these limitations, this study proposes a novel physics-constrained neural network (PCNN) that incorporates constraints on the hypothesis space through designing specialized neural network architectures informed by physical domain knowledge. This approach enables the updating or derivation of biased or unknown components through data-driven learning. Using the development of GMMs as an illustration, the PCNN is constructed to maintain the mathematical form consistent with established empirical models by reconfiguring parameters, activation functions, and layer connections within a conventional neural network. This physics-constrained approach enhances both the interpretability of the network's architecture and the explainability of its outputs. By leveraging both the advanced machine learning techniques and the domain-specific physical constraints, the PCNN refines the suboptimal coefficients in empirical models, which could achieve the globally optimal model coefficients and improve predictive performance.

地震动模型（GMM）对于地震灾害分析至关重要，可以使用经验方法或机器学习方法开发。前者通常会导致次优的预测性能，后者虽然能提供更准确的结果，但经常面临可解释性和可说明性方面的挑战。为了克服这些局限性，本研究提出了一种新颖的物理约束神经网络（PCNN），通过设计以物理领域知识为基础的专门神经网络架构，对假设空间进行约束。这种方法能够通过数据驱动学习更新或推导出有偏差或未知的成分。以 GMM 的发展为例，PCNN 是通过在传统神经网络中重新配置参数、激活函数和层连接来构建的，其数学形式与已建立的经验模型保持一致。这种物理约束方法增强了网络架构的可解释性及其输出的可解释性。通过利用先进的机器学习技术和特定领域的物理约束，PCNN 可完善经验模型中的次优系数，从而实现全局最优模型系数并提高预测性能。

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引用次数: 0

Simulation and numerical analysis of the seismic performance of the quick repaired seismic-damaged RC frame 地震受损快速修复 RC 框架抗震性能的模拟和数值分析

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-13 DOI: 10.1016/j.soildyn.2024.109083

Chang Gao , Liang Huang , Lei Wang , Qiang Sun , Yin Li

This paper presents a finite element (FE) analysis of the seismic performance of the quick repaired seismic-damaged RC frame under low cyclic loading. The quick repair was realized by applying the wire mesh combined with ultra-high early strength grouting materials. The FE model was established based on the constitutive relationship of each materials and validated against the previous experimental results in the literature. The simulated results indicated that the repair could effectively exert the seismic performance of RC frame. Then, the FE parametric analysis was conducted to investigate the influence of studied parameters on the seismic performance of the quick repaired seismic-damaged RC frame models. The analyzed parameters included the axial compressive ratio of columns, the thickness and the height of the repair layer. The numerical analysis showed that the seismic performance of quick repaired seismic-damaged RC frame could be enhanced by the certain increase of the axial compressive ratio. The thickness and height of the repair layer exhibited limited influence on the seismic performance of the RC frame. The paper reported the design suggestions for the quick repaired damaged RC frame.

本文对地震破坏的快速修复 RC 框架在低循环荷载下的抗震性能进行了有限元（FE）分析。快速修复是通过应用钢丝网和超高早强灌浆材料来实现的。根据每种材料的构成关系建立了有限元模型，并与之前的文献实验结果进行了验证。模拟结果表明，修补能有效发挥 RC 框架的抗震性能。然后，进行了有限元参数分析，研究了所研究参数对快速修复的地震损伤 RC 框架模型抗震性能的影响。所分析的参数包括柱的轴向压缩比、修复层的厚度和高度。数值分析表明，在一定程度上提高轴压比可以提高地震损伤快速修复 RC 框架的抗震性能。修复层的厚度和高度对 RC 框架抗震性能的影响有限。本文报告了快速修复受损 RC 框架的设计建议。

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引用次数: 0

Post-tensioned coupling beams: Mechanics, cyclic response, and damage evaluation 后张耦合梁：力学、循环响应和损伤评估

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-13 DOI: 10.1016/j.soildyn.2024.109082

Abouzar Jafari , Amir Ali Shahmansouri , Sepideh Pourshamsian , Habib Akbarzadeh Bengar , Ying Zhou

This study investigates the influence of axial load ratio, initial prestressing ratio, and aspect ratio on the cyclic performance of post-tensioned coupling beams. An analytical solution was derived and verified against experimental studies conducted on post-tensioned beams and a comprehensive numerical parametric analysis was conducted, examining fifty-one scenarios with varying design parameters. These scenarios incorporated three key parameters: the beams’ aspect ratio (span to height), ranging from 1.5 to 3.5; the axial load ratio, ranging from 0.04 to 0.175; and the initial prestressing ratio, ranging from 0.35 to 0.65. Increasing the axial load ratio led to more severe damage, while higher aspect and initial prestressing ratios reduced damage. The axial load ratio had the greatest effect on damage severity, while the aspect ratio mainly influenced the size and length of crushed regions at the beam corners. Deeper post-tensioned coupling beams (aspect ratio <2.5) showed higher coupling shear forces. Increasing the axial load ratio significantly boosted shear capacity, while a higher initial prestressing ratio slightly reduced it. Additionally, both a higher axial load ratio and aspect ratio increased ultimate beam chord rotation, whereas higher initial prestressing ratios decrease it. The estimated stiffness factor, ranging from 0.04 to 0.4, decreased with smaller aspect ratios. Both axial load and initial prestressing ratios had a similar influence on the stiffness factor. A smaller axial load ratio reduced beam-wall interaction and lowered the stiffness ratio, while increasing the initial prestressing ratio raised compressive stress at beam corners, leading to higher initial stiffness and a larger effective moment of inertia. These estimated stiffness factors were then used to derive a relation for the design of post-tensioned coupling beams.

本研究探讨了轴向荷载比、初始预应力比和长宽比对后张法耦合梁循环性能的影响。根据对后张梁进行的实验研究，得出并验证了一个分析解决方案，并进行了全面的数值参数分析，研究了 51 种设计参数不同的情况。这些方案包含三个关键参数：梁的长宽比（跨度与高度），从 1.5 到 3.5 不等；轴向荷载比，从 0.04 到 0.175 不等；初始预应力比，从 0.35 到 0.65 不等。提高轴向荷载比会导致更严重的损坏，而提高纵横比和初始预应力比则会减少损坏。轴向荷载比对损坏严重程度的影响最大，而纵横比则主要影响梁角破碎区域的大小和长度。较深的后张法耦合梁（纵横比为 2.5）显示出较高的耦合剪力。增加轴向荷载比可显著提高剪切承载力，而增加初始预应力比则会略微降低剪切承载力。此外，较高的轴向荷载比和高宽比都会增加梁的极限弦线旋转，而较高的初始预应力比则会降低极限弦线旋转。估计的刚度系数从 0.04 到 0.4 不等，随着纵横比的减小而减小。轴向荷载和初始预应力比对刚度系数的影响相似。较小的轴向荷载比减少了梁与墙的相互作用，降低了刚度比，而增加初始预应力比则提高了梁角处的压应力，导致较高的初始刚度和较大的有效惯性矩。这些估计的刚度系数随后被用于推导后张法耦合梁的设计关系。

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引用次数: 0

The deformation characteristics of modified lightweight expanded polystyrene soils under cyclical loading 改性轻质发泡聚苯乙烯土在循环荷载作用下的变形特性

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-13 DOI: 10.1016/j.soildyn.2024.109074

Ping Jiang , Yuming Fu , Wei Wang , Xuhui Zhou , Na Li , Huaqiang Tao

A dynamic triaxial test was conducted to assess the deformation characteristics of sodium silicate modified EPS (expanded polystyrene) particle lightweight soil (SCS) under cyclical loading. The hysteresis curves, dynamic elastic modulus, damping ratio, and cumulative strain were obtained for SCS samples with varying EPS particle content. We found that the samples' stress-strain hysteresis curves, became crescent-shaped for different dynamic stress situations, and were largely elastic in the latter phases. Furthermore, there was a progression from dense to sparse as EPS content increased. With increasing dynamic stress, the dynamic elastic modulus and damping ratio of SCS also rose. The damping ratio of SCS rose as the EPS particle content increased, whereas the dynamic elastic modulus decreased. Notably, increases in the PS particle content and dynamic stress largen the deformation of the SCS samples. Moreover, we found that when the cumulative strain curve becomes stable, varying the contents of EPS particles under different dynamic stresses leads to a power function relationship with the logarithm of the number of cyclic loading cycles. In cases where the cumulative strain curve reaches a critical or destruction point, the cumulative damage variable displays a power function relationship with the vibration count.

为评估硅酸钠改性 EPS（发泡聚苯乙烯）颗粒轻质土（SCS）在循环加载下的变形特性，进行了动态三轴试验。我们获得了不同 EPS 颗粒含量的 SCS 样品的滞后曲线、动态弹性模量、阻尼比和累积应变。我们发现，在不同的动应力情况下，样品的应力-应变滞后曲线呈新月形，并且在后一阶段基本上是弹性的。此外，随着 EPS 含量的增加，出现了由密到疏的过程。随着动应力的增加，SCS 的动弹性模量和阻尼比也在上升。随着 EPS 颗粒含量的增加，SCS 的阻尼比上升，而动态弹性模量下降。值得注意的是，PS 颗粒含量和动态应力的增加使 SCS 样品的变形增大。此外，我们还发现，当累积应变曲线趋于稳定时，在不同的动态应力下改变 EPS 颗粒的含量会导致与循环加载次数对数的幂函数关系。当累积应变曲线达到临界点或破坏点时，累积破坏变量与振动次数呈幂函数关系。

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引用次数: 0

A correlation for cyclic degradation of natural clayey and sandy soils at different strain amplitudes 天然粘土和砂土在不同应变振幅下的循环降解相关性

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-13 DOI: 10.1016/j.soildyn.2024.109084

J. Jalili, M.K. Jafari

Cyclic degradation of soil significantly affects its behavior in seismic analyses, especially at relatively large strain levels. Beyond the threshold shear strain for degradation, soil properties, including its stiffness and damping, may change dramatically with each loading cycle. The present study aims to extend the investigation by probing the effect of cyclic degradation in greater detail, interpreting results from cyclic tests conducted at an advanced laboratory. In this regard, the results of 77 cyclic tests on natural sandy and clayey soils were analyzed. It was observed that the threshold strain for degradation is 1–2 × 10⁻⁴ for clayey soils and 3 to 4 × 10⁻⁴ for sandy soils. Furthermore, a correlation is proposed between degradation parameters and strain, which is useful for predicting the shear modulus for a desired loop number in cases where only the shear modulus of the 1st loop is available. To ensure the accuracy of this correlation, two additional tests were conducted in the laboratory. The predictions showed satisfactory agreement with the measurements. It was observed that after 15 loading cycles, the shear modulus of the soil decreased to 30–40 % of its initial value at the first cycle. This degraded modulus could be estimated using the correlation proposed in this study, with a 10 % margin of error. This validation supports the applicability of the proposed correlation.

在地震分析中，土壤的循环降解会对其行为产生重大影响，尤其是在相对较大的应变水平下。超过降解的剪切应变阈值后，土壤特性（包括其刚度和阻尼）可能会随着每个加载周期发生巨大变化。本研究旨在扩大调查范围，更详细地探究循环降解的影响，解释在先进实验室进行的循环测试结果。为此，对天然砂土和粘性土的 77 次循环测试结果进行了分析。结果表明，粘土降解的临界应变为 1-2 × 10-4，砂土为 3 至 4 × 10-4。此外，还提出了降解参数与应变之间的相关性，这对于在仅有第一环剪切模量的情况下预测所需环数的剪切模量非常有用。为了确保这种相关性的准确性，在实验室中又进行了两次测试。预测结果与测量结果的一致性令人满意。据观察，经过 15 个加载循环后，土壤的剪切模量下降到第一个循环初始值的 30-40%。使用本研究提出的相关方法可以估算出这一降低的模量，误差范围为 10%。这一验证支持了所建议的相关性的适用性。

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引用次数: 0

Seismic performance enhancement for low-rise and mid-rise steel frames using novel self-centering beam-to-brace links 利用新型自定心梁与梁连接件提高中低层钢结构的抗震性能

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-12 DOI: 10.1016/j.soildyn.2024.109066

Shaoyuan Zhang , Hetao Hou , Yi Liu , Junjie Wang , Chunxue Dai , Bing Qu , Xinrui Fu

This paper aims to propose a novel self-centering beam-to-brace link with examined Shape Memory Alloy (SMA) based apparatuses to improve the seismic resilience of steel frames. Based on the past experimental data, a three-dimensional computer model of the proposed link was established to simulate the nonlinear hysteretic behavior. The results showed that the proposed link could realize the perceived advantages. A simplified Finite Element (FE) model was developed and validated via the comparison with the computer model. A 3-story and a 9-story representative building were rehabilitated with the proposed link. The Nonlinear Response History Analyses (NRHAs) were conducted on the original and rehabilitated systems to evaluate their seismic performance comparatively. To achieve a fair comparison, the original and rehabilitated systems had the proximate vibration periods and the same flexural strength under a roof drift ratio of 2 %. Compared with the original systems, the corresponding rehabilitated systems exhibited equivalent performance of transient inter-story displacement, significant advantages in eliminating residual deformation, and slight disadvantages in limiting floor acceleration. A comprehensive measure was developed and revealed the rehabilitated systems achieved superior seismic overall performance compared to the original systems.

本文旨在提出一种新型的自定心梁-支撑连接件，该连接件采用了经检测的基于形状记忆合金（SMA）的装置，以提高钢框架的抗震能力。根据过去的实验数据，建立了拟议连接的三维计算机模型，以模拟非线性滞回行为。结果表明，拟议的连接件可以实现预期的优势。通过与计算机模型的比较，开发并验证了简化的有限元（FE）模型。一栋 3 层和一栋 9 层的代表性建筑采用了所建议的连接装置进行了修复。对原有系统和修复系统进行了非线性响应历史分析 (NRHA)，以比较评估它们的抗震性能。为了进行公平比较，在屋顶漂移率为 2% 的情况下，原有系统和修复系统的振动周期相近，抗弯强度相同。与原有系统相比，相应的修复系统在瞬态层间位移方面表现出同等性能，在消除残余变形方面具有显著优势，而在限制楼层加速度方面则略显不足。综合测量结果表明，与原有系统相比，修复后的系统具有更优越的抗震综合性能。

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引用次数: 0

Ground motions around a partially ﬁlled semi-circular alluvial valley with a lined tunnel under cylindrical SH waves 在圆柱形 SH 波作用下，带衬砌隧道的半圆形冲积谷地周围的地面运动

IF 4.2 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2024-11-12 DOI: 10.1016/j.soildyn.2024.109073

Bo He , Yuanming Lai , Lizhou Wu , Shuairun Zhu , Xu Li

The interaction between surface irregularities and underground tunnels has notable effect on seismic waves, resulting in amplification or attenuation of ground motions. However, previous studies for scattering issue induced by the interaction between irregular topographies and understructures were only based on the assumption of plane shear horizontal (SH) waves. Actually, the significance of source effects on topographic amplification cannot be underestimated. Meanwhile, the thickness and material damping of local alluvium can exert momentous influence on ground motions. In this study, a series solution is proposed to tackle the scattering phenomenon caused by a partially filled semi-circular alluvial valley with a lined tunnel under cylindrical SH waves, and the impact of source distance on the ground motions of the irregular topography with a tunnel is revealed for the first time. Firstly, the wave-function expansion approach and classical mirror image method are developed to constructive wave-function expressions in different polar coordinate systems. Then, applying the appropriate Graf's addition formula, it becomes possible to unify the coordinate systems for different subregions. Furthermore, according to continuity conditions of stress and displacement, the region-matching technique is adopted to determine the unknown coefficients of the algebraic equations. Finally, to illustrate the interaction between a partially ﬁlled alluvial valley and a lined tunnel on ground motions, a comprehensive parametric analysis is performed in both the frequency and time domains. A significant finding is that ground motions of combined topography is affected by the source location, and the source distance cannot be disregarded unless the source distance surpasses 100-time valley width. This indicates the need to closely examine how the source location influences the amplification effect due to combined topography, particularly when the source is near the terrain.

地表不规则地形与地下隧道之间的相互作用会对地震波产生显著影响，导致地面运动的放大或衰减。然而，以往对不规则地形与地下结构相互作用引起的散射问题的研究仅基于平面剪切水平（SH）波的假设。实际上，震源效应对地形放大的影响不容低估。同时，当地冲积层的厚度和材料阻尼也会对地面运动产生巨大影响。本研究针对带衬砌隧道的部分充填半圆形冲积谷地在圆柱 SH 波作用下产生的散射现象，提出了一种系列解法，首次揭示了源距对带隧道不规则地形地面运动的影响。首先，建立了波函数展开方法和经典镜像法，以构造不同极坐标系下的波函数表达式。然后，应用适当的格拉夫加法公式，可以统一不同子区域的坐标系。此外，根据应力和位移的连续性条件，采用区域匹配技术确定代数方程的未知系数。最后，为了说明部分充填的冲积河谷和衬砌隧道之间的相互作用对地面运动的影响，在频域和时域进行了全面的参数分析。一个重要的发现是，组合地形的地面运动受到震源位置的影响，除非震源距离超过 100 倍的谷宽，否则不能忽略震源距离。这表明有必要仔细研究震源位置如何影响组合地形引起的放大效应，特别是当震源靠近地形时。

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引用次数: 0