Soil Dynamics and Earthquake Engineering最新文献_第6页

Experimental investigation of the seismic response and ultimate lateral resistance of pile–superstructure systems considering ground settlement due to pore water dissipation 考虑孔隙水耗散沉降的桩-上部结构体系地震响应及极限侧阻力试验研究

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-22 DOI: 10.1016/j.soildyn.2025.110050

Mutsuki Sato, Yoshihiro Kimura

This study investigates the seismic response and ultimate lateral resistance of pile–superstructure systems subjected to repeated earthquake loadings in liquefiable ground. A series of centrifuge model tests was conducted using scaled specimens (1/40 scale) to reproduce the progressive process of ground settlement, pile head exposure, and pile failure under multiple shakings. The tests successfully simulated liquefaction-induced ground settlement and consolidation, leading to pile damage dominated by local buckling near the pile head. Spectral analyses of acceleration records before liquefaction revealed that, while settlement and soil densification had only a limited influence on the system's natural period, pile plasticization played a dominant role in lengthening the period. Comparison between inertial forces of the superstructure and measured pile head shear forces demonstrated good agreement, validating the data correction methods and skeleton curve adopted. It was observed that, when liquefaction occurred, superstructure responses decreased markedly, and pile axial forces fluctuated less. Plastic hinge development was traced through bending moment histories, and final failure was attributed to local buckling, consistent with visual inspection of the specimens. The ultimate lateral resistance of the pile foundation, accounting for ground settlement, was found to decrease by approximately 8.3 % compared to the initial state. These findings highlight the significance of time-dependent ground changes, such as consolidation-induced settlement and liquefaction, in long-life structures. The results contribute to establishing design methodologies for pile foundations that explicitly incorporate inevitable ground property changes during service life.

本文研究了液化地基中桩-上部结构体系在重复地震荷载作用下的地震反应和极限侧向抗力。采用1/40比例尺进行了一系列离心模型试验，再现了多次震动作用下地基沉降、桩顶暴露、桩破坏的渐进过程。试验成功地模拟了液化引起的地基沉降固结，从而导致桩的破坏以桩头附近的局部屈曲为主。液化前加速度记录的频谱分析表明，沉降和土壤致密化对系统自然周期的影响有限，桩体塑化对系统自然周期的延长起主导作用。上部结构惯性力与实测桩顶剪力的对比结果吻合较好，验证了所采用的数据校正方法和骨架曲线。观察到，当液化发生时，上部结构响应明显减小，桩轴力波动较小。塑性铰的发展是通过弯矩历史来追踪的，最终的破坏归因于局部屈曲，与目视检查的试样一致。与初始状态相比，考虑地面沉降的桩基极限侧阻力降低了约8.3%。这些发现强调了随时间变化的地面变化的重要性，如固结引起的沉降和液化，在长寿命结构中。研究结果有助于建立明确考虑在使用寿命期间不可避免的地面性质变化的桩基设计方法。

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引用次数: 0

Non-parametric ground motion duration and energy-based intensity measure models: A novel stacking ensemble model using regional seismic data 非参数地震动持续时间和基于能量的强度测量模型：一种基于区域地震数据的叠加系综模型

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-21 DOI: 10.1016/j.soildyn.2026.110135

Tugce Tetik , Pınar Cihan

This study leverages data-driven Machine Learning (ML) algorithms and Türkiye's regional ground motion (GM) database (1983–2025) to predict significant durations (D_5–75, D_5–95, D_20–80), Cumulative Absolute Velocity (CAV), and Housner Intensity (SI). The models evaluated include Extreme Gradient Boosting (XGBoost), Random Forest (RF), Gradient Boosting Regression (GBR), Linear Regression (LR), and two stacking ensemble models. The Stacking-GBR model yielded the best performance, with R² values of 0.987 and 0.988 for SI and CAV, respectively. Compared with established empirical equations (e.g., BSA09 for duration and CB19 for CAV), the proposed framework achieves a 20–25 % reduction in total variability (σ) for duration metrics. The SHapley Additive exPlanations (SHAP) analysis reveals that moment magnitude (M_w) and rupture distance govern scaling and attenuation, whereas Vs₃₀ and basin-depth proxies capture site-amplification effects, supporting the model's physical interpretability of the model. Crucially, a SHAP-informed model reduction further demonstrates that physically motivated predictors (M_w, R_RUP, Vs₃₀) retain strong predictive capability for energy-based intensity measures, supporting practical applicability when detailed source parameters are unavailable. Residual analyses indicate that duration metrics are more sensitive to source and site variability, particularly at smaller magnitudes and in softer soils, while energy-based measures, especially SI, exhibit greater stability and lower model uncertainty. The findings highlight that the integration of ML with explainability methods enhances the predictive accuracy and physical interpretability of seismic intensity measures, supporting performance-based earthquake engineering and regional hazard assessment.

本研究利用数据驱动的机器学习（ML）算法和 rkiye的区域地面运动（GM）数据库（1983-2025）来预测显著持续时间（D5-75、D5-95、D20-80）、累积绝对速度（CAV）和豪斯纳强度（SI）。评估的模型包括极端梯度增强（XGBoost）、随机森林（RF）、梯度增强回归（GBR）、线性回归（LR）和两个堆叠集成模型。以Stacking-GBR模型表现最佳，SI和CAV的R2分别为0.987和0.988。与已建立的经验方程（例如，持续时间的BSA09和CAV的CB19）相比，所提出的框架在持续时间度量的总变异性（σ）上降低了20 - 25%。SHapley加性解释（SHAP）分析表明，矩量级（Mw）和破裂距离控制着尺度和衰减，而Vs30和基底深度代理捕获了场地放大效应，支持了模型的物理可解释性。至关重要的是，基于shap的模型简化进一步证明了物理驱动的预测因子（Mw、RRUP、Vs30）对基于能量的强度测量保留了强大的预测能力，支持在无法获得详细源参数时的实际适用性。残差分析表明，持续时间指标对震源和场地变率更敏感，特别是在较小震级和较软的土壤中，而基于能量的测量，特别是SI，表现出更大的稳定性和更低的模型不确定性。研究结果表明，ML与可解释性方法的结合提高了地震烈度测量的预测精度和物理可解释性，为基于性能的地震工程和区域灾害评估提供了支持。

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引用次数: 0

An enhanced semi-active nonlinear negative stiffness control strategy based on isolation-story displacement triggering 基于隔层位移触发的增强型半主动非线性负刚度控制策略

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-19 DOI: 10.1016/j.soildyn.2026.110134

Yafei Zhang , Ning Li , Yuchen Hu , Tianchang Li

This study proposes a displacement-triggered semi-active nonlinear negative stiffness device (DTSA-NNSD) control strategy to enhance the seismic resilience of base-isolated structures. The device employs a helical spring-based nonlinear mechanism that provides adaptive negative stiffness under controlled compression. A key innovation of the DTSA-NNSD is its displacement-triggered activation: the negative stiffness mechanism engages in response to real-time isolation story displacement, keeping the spring within the elastic range and reducing fatigue-induced performance degradation. The effectiveness of the proposed strategy is validated through combining real-time hybrid simulation with dual servo-hydraulic actuators and numerical simulations under multiple seismic intensity levels. Compared with passive NNSD control and uncontrolled cases, DTSA-NNSD achieves 40 %–60 % reduction in peak isolation displacement and up to 40 % reduction in superstructure acceleration, while generating stronger nonlinear negative stiffness forces for enhanced energy dissipation. Sensitivity analysis further highlights the crucial role of the compression ratio in controlling performance. The results demonstrate that the DTSA-NNSD offers a practical semi-active approach to balance adaptability, structural safety, and long-term efficiency in seismic isolation systems. Future work may focus on real-time optimization of control parameters and integration with data-driven monitoring frameworks for robust seismic protection.

为提高基础隔震结构的抗震能力，提出了一种位移触发半主动非线性负刚度装置（DTSA-NNSD）控制策略。该装置采用基于螺旋弹簧的非线性机构，在受控压缩下提供自适应负刚度。DTSA-NNSD的一个关键创新是其位移触发激活：负刚度机制响应实时隔离层位移，使弹簧保持在弹性范围内，减少疲劳引起的性能下降。通过双伺服液压作动器实时混合仿真和多烈度下的数值模拟，验证了该策略的有效性。与被动NNSD控制和不受控制的情况相比，dsa -NNSD可使隔震峰值位移减小40% - 60%，上层结构加速度减小40%，同时产生更强的非线性负刚度力，以增强能量耗散。灵敏度分析进一步强调了压缩比在控制性能中的关键作用。结果表明，DTSA-NNSD为隔震系统的平衡适应性、结构安全性和长期效率提供了一种实用的半主动方法。未来的工作可能集中在控制参数的实时优化和与数据驱动的监测框架的集成上，以实现强大的地震防护。

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引用次数: 0

Dynamic seepage analysis of unsaturated subgrade bed for ballastless track considering rainfall and train loading 考虑降雨和列车荷载的非饱和路基路基动力渗流分析

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-19 DOI: 10.1016/j.soildyn.2026.110130

Yanfei Pei , Yipeng Lai , Kaiwen Liu , Rui Su , Ping Wang

The migration and storage of moisture within the subgrade critically effect the long-term stability of ballastless tracks. Accordingly, this study presents two principal innovations: 1) a computational model for subgrade moisture migration under coupled rainfall infiltration and train loading, and 2) an analysis of pore-water migration pathways and dynamic pore-water pressure characteristics. First, the soil-water characteristic curve of the subgrade bed layer was obtained. A coupled static–dynamic model for unsaturated seepage in the subgrade was then established and validated through model tests, slope rainfall–infiltration simulations, and wheel-rail coupling analyses. Results indicate that moisture transport within the subgrade bed exhibits a horn-shaped distribution, with higher water content at the base and gradual reduction toward both sides. The wetting pattern is progressive and spatially non-uniform. As the wetting front advances downward, the location of maximum dynamic pore-water pressure progressively shifts downward. Train-induced vibration accelerates unsaturated infiltration from slow to fast. When the wetting front reaches the bottom of the subgrade bed surface layer and forms a perched water zone, the maximum dynamic pore-water pressure remains at approximately 30 cm above the base.

路基内水分的迁移和储存对无砟轨道的长期稳定性有着至关重要的影响。因此，本研究提出了两个主要创新点：1)建立了降雨入渗和列车加载耦合作用下的路基水分迁移计算模型；2)分析了孔隙水迁移路径和动态孔隙水压力特征。首先，获得了路基床层的土水特征曲线；建立了路基非饱和渗流的动静耦合模型，并通过模型试验、坡面降雨入渗模拟和轮轨耦合分析进行了验证。结果表明：路基内水分输运呈“喇叭”形分布，底部含水量较高，两侧逐渐减少；润湿模式具有递进性和空间不均匀性。随着润湿锋向下推进，最大动孔水压力位置逐渐向下移动。列车振动使非饱和渗透由慢变快。当润湿锋到达路基床面层底部形成悬泊水区时，最大动孔水压力保持在地基上方约30cm处。

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引用次数: 0

Correlation between liquefaction resistance and shear wave velocity of sand-gravel mixtures: An experimental investigation 砂砾混合料液化阻力与剪切波速关系的实验研究

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-17 DOI: 10.1016/j.soildyn.2026.110124

Abilash Pokhrel , Gabriele Chiaro

Case histories from more than 30 earthquakes worldwide have shown that liquefaction can occur in gravelly soils (both in natural deposits and manmade reclamations), resulting in large ground deformation and severe damage to civil infrastructure. However, evaluating the liquefaction potential and cyclic strain accumulation characteristics of gravelly soils remains a major challenge in geotechnical earthquake engineering. In this study, to provide new insights into this important topic, a series of stress-controlled undrained cyclic triaxial tests were performed, along with bender element shear wave velocity (V_S) measurements, on reconstituted specimens of sand-gravel mixtures (SGM) with varying gravel contents (G_C) and relative densities (D_r). The experimental results indicated that both G_C and D_r have significant effects on the cyclic resistance ratio (CRR) and V_S of SGMs, and both parameters should be considered jointly when evaluating the cyclic response, as similar macroscopic behavior can result from different combinations of density state and particle-size composition. Laboratory-based G_C-specific CRR-V_S correlations were also developed and found to be consistent with existing V_S-based liquefaction triggering relationships derived from gravelly soil case histories.

全球30多次地震的历史案例表明，液化可能发生在砾石土壤中（包括天然沉积物和人工填海），导致地面大变形和对民用基础设施的严重破坏。然而，评估砂砾土的液化潜力和循环应变积累特性仍然是岩土地震工程中的一个主要挑战。在这项研究中，为了对这一重要课题提供新的见解，对具有不同砾石含量（GC）和相对密度（Dr）的砂砾混合物（SGM）的重建样品进行了一系列应力控制的不排水循环三轴试验，并进行了弯曲单元剪切波速（VS）测量。实验结果表明，GC和Dr对sgm的循环阻力比（CRR）和VS有显著影响，在评价循环响应时应联合考虑这两个参数，因为密度状态和粒径组成的不同组合会导致相似的宏观行为。基于实验室的gc特异性CRR-VS相关性也被开发出来，并发现与现有的基于vs的液化触发关系是一致的，这些关系来源于砾石土案例历史。

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引用次数: 0

DAS scaling relations for S-waves in Mexico City: From peak ground motion to spectral amplitude and acceleration assessment 墨西哥城s波的DAS标度关系：从地面运动峰值到频谱振幅和加速度评估

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-17 DOI: 10.1016/j.soildyn.2026.110126

Manuel J. Aguilar-Velázquez , Satoshi Ide , Mathieu Perton , Zack J. Spica

Distributed Acoustic Sensing (DAS) is popular in seismological research for its high-resolution, spatially distributed seismic records. Unlike conventional seismic instruments, DAS measures strain rate, which requires appropriate scaling to interpret the data in terms of ground motion. This article presents two perspectives on S-wave DAS-based scaling relations for earthquakes recorded in Mexico City. The first perspective explores two models. (1) a frequency-independent relation that uses earthquake magnitude, hypocentral distance, and average site response to explain the peak strain rate amplitude. (2) a frequency-dependent relation that incorporates the source spectrum, hypocentral distance, and a frequency-dependent site response to derive the strain-rate spectrum. The second perspective explores the well-known proportional relationship between strain rate and acceleration records using a nearby seismic station data. Our results show that, for the first-perspective models, the source and geometrical spreading coefficients match theoretical expectations, while

M_{0}

retrieval from (2) is well constrained within in a frequency band limited by the signal-to-noise ratio (suggesting reliability for

M_{w} \leq

5.0), and the site effect terms correlate with the geological and infrastructural features. For the second perspective, as anticipated, we confirm that the strain rate-acceleration proportionality is governed by shallow S-wave velocity in minimally stratified structures. Analogous to a puzzle, the first-perspective models provide practical tools for estimating earthquake magnitude and characterizing site effects. In conjunction with the rapid PGA estimations derived from the second perspective, DAS can be positioned as a powerful tool with for seismic studies in Mexico City.

分布式声传感技术以其高分辨率、空间分布的地震记录在地震学研究中受到广泛应用。与传统的地震仪器不同，DAS测量应变率，这需要适当的缩放来解释地面运动方面的数据。本文介绍了墨西哥城地震记录中基于s波das的标度关系的两种观点。第一个视角探讨了两个模型。(1)利用地震震级、震源距离和平均场地响应来解释峰值应变率幅值的频率无关关系。(2)结合源谱、震源距离和频率相关的场地响应的频率相关关系，推导出应变率谱。第二种方法利用附近地震台站的数据，探讨了众所周知的应变率和加速度记录之间的比例关系。我们的研究结果表明，对于第一视角模型，源和几何扩展系数符合理论预期，而从(2)中检索的M0很好地限制在受信噪比限制的频带内（表明Mw≤5.0的可靠性），并且场地效应项与地质和基础设施特征相关。对于第二个角度，正如预期的那样，我们证实了应变速率-加速度比例是由最小层状结构中的浅s波速度控制的。类似于拼图，第一视角模型为估计地震震级和描述场地效应提供了实用的工具。结合从第二个角度得出的快速PGA估计，DAS可以定位为墨西哥城地震研究的强大工具。

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引用次数: 0

Improvement of seismic wave detection using genetic algorithm–based optimized FIR filters 基于遗传算法的优化FIR滤波器对地震波探测的改进

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-16 DOI: 10.1016/j.soildyn.2026.110122

Seda Guzel Aydin

Seismic signals are used for the detection of ongoing earthquakes, the assessment of their magnitudes, and the identification of their source locations. However, seismic signals are often recorded alongside unwanted interference perceived as noise, making it challenging to extract the desired information. This study aimed to ensure the accurate detection of earthquake events by effectively eliminating noise from seismic signals, thereby enhancing the identification of seismic occurrences. A novel genetic algorithm (GA)–based window function was developed to achieve an efficient filter design by minimizing undesirable side lobes and fluctuations in the transition band in digital filtering. As a noise reduction technique, the GA-based finite impulse response digital filtering method (GAFIR) was employed. To evaluate the filtered signals, a modified short-term average–long-term average method was used. Using the proposed approach, the accuracy and recall metrics improved from 0.88 to 0.86 to 0.956 and 1.0, respectively. The study concludes that seismic signals filtered using the proposed GAFIR method are capable of predicting earthquake occurrences with high precision.

地震信号用于探测正在发生的地震，评估其震级，并确定其震源位置。然而，地震信号通常与被认为是噪声的不必要干扰一起记录，这使得提取所需信息变得困难。本研究旨在通过有效地消除地震信号中的噪声，从而提高地震发生的识别能力，保证地震事件的准确检测。提出了一种新的基于遗传算法的窗函数，通过最小化数字滤波中不需要的旁瓣和过渡带的波动来实现有效的滤波器设计。作为一种降噪技术，采用了基于遗传算法的有限脉冲响应数字滤波方法（GAFIR）。为了对滤波后的信号进行评价，采用了一种改进的短期平均-长期平均方法。使用该方法，准确率和召回率指标分别从0.88到0.86提高到0.956和1.0。研究表明，采用GAFIR方法滤波后的地震信号能够较高精度地预测地震发生。

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引用次数: 0

Robustness analysis of HVSR-derived soil fundamental frequency estimates in an urban seismic network 城市地震台网中基于hvrr的土壤基频估计的鲁棒性分析

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-14 DOI: 10.1016/j.soildyn.2026.110108

Kaan Hakan Coban , Jordi Díaz , Albert Macau , Helena Seivane , Sara Figueras , Martin Schimmel , Pilar Sánchez-Pastor , Samuel Jorde

Microtremor data acquired using permanent and temporary seismic deployments within the city of Barcelona were used to systematically analyze the robustness of the soil fundamental frequency and horizontal to vertical spectral ratio (HVSR) amplitude estimates, leveraging the long recording period, in the order of several months, available for most of the stations. The analysis considers different time-window lengths, times of day, and seasons of the year. Overall, the results are consistent; however, we identified specific time intervals in which the results, particularly the amplitude of the HVSR peak, deviate significantly from the mean. We have observed that during these intervals, the seismic energy in the microseismic peak is lower than average, due to reduced sea wave activity. Therefore, we interpret that during the periods of calm seas, the HVSR results may be biased because of insufficient seismic energy. The new set of HVSR estimates has been integrated with existing data to obtain an updated map of the soil fundamental frequency in Barcelona, contributing to improved microzonation and seismic risk assessment in the city. Furthermore, we show that the soil fundamental frequency map serve as a proxy of the thickness of the Cenozoic sedimentary cover, yielding results consistent with previous observations based on variations in the amplitude of ambient seismic noise in the 2–20 Hz band during the period of low anthropogenic activity caused by the lockdown measures decreed during the COVID-19 pandemic.

在巴塞罗那市使用永久和临时地震部署获得的微震数据被用于系统地分析土壤基频和水平与垂直频谱比（HVSR）振幅估计的鲁棒性，利用大多数台站可获得的长记录周期，以几个月为单位。该分析考虑了不同的时间窗口长度、一天中的时间和一年中的季节。总的来说，结果是一致的；然而，我们确定了特定的时间间隔，其中结果，特别是HVSR峰值的幅度，明显偏离平均值。我们观察到，在这些间隔期间，由于海浪活动减少，微震峰的地震能量低于平均水平。因此，我们解释，在海面平静期，由于地震能量不足，HVSR结果可能会有偏差。新的HVSR估计值与现有数据相结合，获得了巴塞罗那土壤基本频率的更新地图，有助于改善城市的微带和地震风险评估。此外，我们表明，土壤基频图可以代表新生代沉积覆盖厚度，其结果与先前基于在COVID-19大流行期间颁布的封锁措施导致的低人为活动期间2-20 Hz波段环境地震噪声幅度变化的观测结果一致。

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引用次数: 0

Novel self-centering damper for seismic resilience: development, modeling, and validation 新型自定心抗震阻尼器：开发、建模和验证

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-14 DOI: 10.1016/j.soildyn.2026.110123

Beco Chenadaire Lekeufack, Bo Fu, Mabor Achol Samuel

Recent earthquakes in Turkey, Syria, Morocco, and China exposed critical building vulnerabilities under multi-hazard conditions, revealing the urgent need to improve structural resilience beyond strength-focused retrofitting methods like X-bracing and cross-sectional expansion. While these methods offer some improvements, they generally lack sufficient energy dissipation capacity, leading to inadequate performance during extreme events. Recently, self-centering systems have been proposed to address these challenges by combining energy dissipation with automatic recentering. Nevertheless, many existing dampers still face the problem of residual drift, which diminishes performance, compromises safety, and increases economic losses. This study introduces a novel energy-dissipative self-centering damper (NEDSCD) that couples the high energy dissipation of metallic yielding dampers with the reliable recentering ability of pre-compressed disc springs. Unlike shape-memory-alloy-based dampers, the NEDSCD's hybrid design simplifies construction while maintaining stable flag-shaped hysteretic behavior. Theoretical analytical models were developed to characterize the damper's force-displacement response and validated against experimental data from previous studies. To evaluate their performance, three steel moment-resisting frame buildings (5-story, 10-story, and 15-story) were subjected to 22 ground motions through incremental dynamic analysis (IDA). Fragility curve analysis demonstrated that the proposed damper enhances seismic energy absorption and substantially improves resilience compared to conventional dampers. Key resilience improvements at the 50 % probability of damage exceedance were 8.0 % (5-story), 11.5 % (10-story), and 12.5 % (15-story). By effectively combining energy dissipation with autonomous recentering, the NEDSCD offers a scalable, low-maintenance solution for upgrading seismic resilience in vulnerable infrastructure.

最近发生在土耳其、叙利亚、摩洛哥和中国的地震暴露了建筑在多种灾害条件下的关键脆弱性，表明迫切需要提高结构弹性，而不是采用x型支撑和截面扩张等以强度为重点的改造方法。虽然这些方法有一些改进，但它们通常缺乏足够的能量耗散能力，导致在极端事件下性能不佳。最近，人们提出了将能量耗散与自动重新进入相结合的自定心系统来解决这些挑战。然而，许多现有的阻尼器仍然面临残余漂移的问题，这降低了性能，损害了安全性，并增加了经济损失。本文介绍了一种新型耗能自定心阻尼器（NEDSCD），它将金属屈服阻尼器的高能量耗散与预压缩盘式弹簧的可靠重入能力相结合。与基于形状记忆合金的阻尼器不同，NEDSCD的混合设计简化了施工，同时保持了稳定的旗形滞回性能。建立了理论分析模型来表征阻尼器的力-位移响应，并根据先前研究的实验数据进行了验证。为了评估其性能，通过增量动力分析（IDA）对3座钢抗弯矩框架建筑（5层、10层和15层）进行了22次地面运动。脆性曲线分析表明，与传统阻尼器相比，该阻尼器增强了地震能量吸收，并显著提高了回弹能力。在50%的破坏超出概率下，关键的弹性改善率分别为8.0%（5层）、11.5%（10层）和12.5%（15层）。通过有效地将能量耗散与自动重新定向相结合，NEDSCD提供了一种可扩展的、低维护的解决方案，可以提高脆弱基础设施的抗震能力。

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引用次数: 0

Seismic site characterization and classification in Cameroon using full microtremor horizontal-to-vertical spectral ratio analysis and inversion 喀麦隆全微震水平-垂直频谱比分析与反演的地震场址特征与分类

IF 4.6 2区工程技术 Q1 ENGINEERING, GEOLOGICAL

Soil Dynamics and Earthquake Engineering

Pub Date : 2026-01-14 DOI: 10.1016/j.soildyn.2025.110039

Agostiny Marrios Lontsi , Joel Fabiola Tchokouata Tchapleu , Alain Pierre Kamga Tokam , Junior Tabi Ndiparray , Delair Dieudonné Etoundi Ndibi , Serge Beteh , Anthony Wirdzenyuy Jimmesiy , Tabod Charles Tabod

<div><div>The non-destructive and cost-efficient single-station microtremor horizontal-to-vertical (H/V) spectral ratio method was used to characterize the temporary broadband station sites of the Cameroon passive-source seismic experiment. Seismic site characterization was performed by processing ambient seismic noise to obtain the H/V spectral ratio, estimating the site fundamental frequency, inverting the full spectrum of the microtremor H/V curves for shear-wave velocity profiles, and classifying the investigated sites according to established seismic building codes.</div><div>The temporary (2005–2007) Cameroon passive-source seismic experiment deployed 32 three-component broadband seismometers distributed across the country. At each site, the microtremor H/V spectral ratio was estimated over the frequency range of 0.2–20 Hz. The extracted fundamental frequencies ranged from <span><math><mrow><mn>0</mn><mo>.</mo><mn>58</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>09</mn></mrow></math></span> Hz at station CM15 (Melong) to <span><math><mrow><mn>16</mn><mo>.</mo><mn>26</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>09</mn></mrow></math></span> Hz at station CM12 (Ntui), with peak amplitudes varying from 2.2 at station CM09 (Ekona) to 12.7 at station CM32 (Maroua). These results indicate pronounced site effects associated with variable soil thicknesses and the potential for significant ground-motion amplification during earthquakes.</div><div>Temporal variation in the H/V curves was evaluated over the entire recording period. Although some sites exhibited variations exceeding <span><math><mo>±</mo></math></span>60%, most H/V curves were stable, with amplitude changes generally within <span><math><mo>±</mo></math></span>20%. This stability provided quality assurance that the selected inversion targets were not affected by non-site-related features. The full spectrum of the H/V curves were then inverted to estimate shear-wave velocity (<span><math><msub><mrow><mi>V</mi></mrow><mrow><mi>S</mi></mrow></msub></math></span>) profiles at respective stations. The resulting profiles were compared with those obtained from constrained inversion of the ellipticity curves using the site fundamental frequency. At Campo (CM01), lithological information was further compared with data from an independent electro-seismic survey.</div><div>From the estimated <span><math><msub><mrow><mi>V</mi></mrow><mrow><mi>S</mi></mrow></msub></math></span> profiles, the time-averaged shear-wave velocity in the upper 30 m (<span><math><msub><mrow><mi>V</mi></mrow><mrow><mi>S</mi><mn>30</mn></mrow></msub></math></span>) was calculated for each site. The <span><math><msub><mrow><mi>V</mi></mrow><mrow><mi>S</mi><mn>30</mn></mrow></msub></math></span> values range from 252 to 1691 m/s, corresponding to soil classes C to A according to Eurocode 8. This study provides the first comprehensive database of <span><math><msub><mrow><mi>V</mi></mrow><mrow><mi>S</mi><mn>30</mn></mrow></msub></math></span> a

采用非破坏性、高性价比的单台站微震水平-垂直（H/V）谱比方法对喀麦隆被动震源地震实验的临时宽带台站进行了表征。通过处理环境地震噪声获得H/V谱比，估计场地基频，反演微震H/V曲线的全谱剪切波速剖面，并根据已建立的抗震建筑规范对调查场地进行分类，对地震场地进行表征。临时（2005-2007）喀麦隆被动震源地震实验部署了分布在全国各地的32台三分量宽带地震仪。在0.2 ~ 20hz的频率范围内，估算了各测点的微震H/V谱比。提取的基频范围从CM15站（梅龙）的0.58±0.09 Hz到CM12站（Ntui）的16.26±0.09 Hz，峰值幅度从CM09站（Ekona）的2.2到CM32站（Maroua）的12.7不等。这些结果表明明显的场地效应与不同的土壤厚度和地震期间显著地震动放大的潜力有关。在整个记录期间，对H/V曲线的时间变化进行了评估。虽然部分地点的H/V曲线变化幅度超过±60%，但大多数H/V曲线稳定，幅度变化幅度一般在±20%以内。这种稳定性为所选择的反演目标不受非位点相关特征的影响提供了质量保证。然后反演H/V曲线的全谱，以估计各站点的横波速度（VS）剖面。将所得剖面与利用场址基频对椭圆曲线进行约束反演得到的剖面进行了比较。在Campo (CM01)，进一步将岩性信息与独立电震调查数据进行了比较。根据估计的VS剖面，计算了每个站点30 m以上的时间平均横波速度（VS30）。VS30的取值范围为252至1691米/秒，对应于欧洲法规8中的C至A级土壤。该研究为喀麦隆提供了第一个VS30和现场条件的综合数据库，为未来的地震危险性评估和抗震结构设计提供了宝贵的资源。此外，我们提出了一种新的经验关系，适用于全球土壤条件相似的地区。

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