Soils and Foundations最新文献_第4页

Sandpile experiments and statistical analysis for slope failure, failure shape, and frequency distribution 砂堆试验及边坡破坏的统计分析，破坏形态及频率分布

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-08-01 DOI: 10.1016/j.sandf.2025.101665

W.S.G. Fernando , Yota Togashi , Teppei Kato , Masahiko Osada

Natural slopes, which occur without human intervention, are susceptible to failure triggered by events such as earthquakes and heavy rainfall. The characteristics of these failures, including the shape of the slip surface and the magnitude of collapse, vary significantly due to factors like the direction of seismic motion, ground heterogeneity, and unsteady rainfall infiltration. Despite numerous experimental studies, the probabilistic nature of slope failure phenomena remains insufficiently understood. This study employs experimental and statistical analysis using the sandpile model to elucidate slope failures and their magnitudes. The sandpile model involves gradually adding sand to a pile and repeatedly observing its collapse. Experiments were conducted using silica sand No. 8 (fine sand) on base plates with diameters ranging from 5 cm to 12 cm. Shape variations were captured using a depth camera. The results indicate significant geometric changes predominantly at the apex of the sandpile, where the initial breach of stability occurs. The metastable slope angle at the apex of the sandpile induces hysteresis behavior in slope failure. The frequency of occurrence and failure mass deviates from a normal distribution, with smaller magnitudes occurring more frequently and a sharp decrease in frequency for larger magnitudes. This pattern mirrors the frequency-magnitude relationship observed in earthquakes, with the study’s results aligning with the Gutenberg-Richter law, confirming the hypothesis. The b-value obtained from this study falls within the range of frequency-size landslide statistics available in the literature.

自然斜坡是在没有人为干预的情况下形成的，容易受到地震和强降雨等事件的破坏。由于地震运动方向、地面非均质性和降雨入渗不稳定等因素的影响，这些破坏的特征（包括滑面形状和崩塌幅度）变化很大。尽管进行了大量的试验研究，但对边坡破坏现象的概率性质仍知之甚少。本研究采用砂桩模型对边坡破坏及其震级进行了实验分析和统计分析。砂堆模型涉及到逐渐向桩上加砂，并反复观察其倒塌。实验采用8号硅砂（细砂）在直径为5 cm ~ 12 cm的底板上进行。形状变化是用深度相机捕捉到的。结果表明，砂堆的几何变化主要发生在砂堆的顶端，这是最初破坏稳定的地方。砂桩顶端的亚稳坡角导致边坡失稳的迟滞行为。发生频率和破坏质量偏离正态分布，较小的震级发生频率较高，较大的震级发生频率急剧下降。这种模式反映了在地震中观察到的频率-震级关系，研究结果与古腾堡-里希特定律一致，证实了这一假设。本研究获得的b值在文献中可用的滑坡频率大小统计范围内。

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引用次数: 0

Laboratory tests of measurement systems in pile shafts 桩井测量系统的实验室试验

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-25 DOI: 10.1016/j.sandf.2025.101663

Adam Jabłonowski , Adam Krasiński , Piotr Kanty

The article describes the results of laboratory tests of reinforced concrete pile sections instrumented with several measurement systems. Compression tests were carried out on three 300-mm-by-1.2-m cylindrical pile elements, reinforced with an IPE140 steel profiles. The elements were equipped with vibrating wire sensors for measuring strains and stresses in concrete, and two elements had additional fibre optic cables installed for measuring strains. During the tests, external measurements were also made for axial force and longitudinal deformations of the elements. The aim of the research was to compare the measured values of all the internal and external systems and to evaluate the reliability of internal systems. The analysis of the measurement results showed generally good reliability of strain measurements using local vibrating wire sensors and extensometers and especially fibre optic sensors. Measurements of stresses in concrete using an internal vibrating wire sensor were unfortunately much less reliable. The reasons for the reduced reliability of the stress measurements are discussed and a correction coefficient is proposed. The conclusions state that the research and its results are valuable and useful for measuring and monitoring of foundation piles and columns purposes.

本文介绍了用几种测量系统对钢筋混凝土桩截面进行室内测试的结果。压缩试验在三个300 mm × 1.2 m圆柱桩单元上进行，用IPE140钢型材加固。这些元件配备了振动线传感器，用于测量混凝土中的应变和应力，其中两个元件安装了额外的光纤电缆，用于测量应变。在试验过程中，还对构件的轴向力和纵向变形进行了外部测量。研究的目的是比较所有内部和外部系统的测量值，并评估内部系统的可靠性。对测量结果的分析表明，采用局部振动线传感器和伸缩仪，特别是光纤传感器进行应变测量，总体上具有较好的可靠性。不幸的是，使用内部振动线传感器测量混凝土应力的可靠性要低得多。讨论了应力测量可靠性降低的原因，并提出了修正系数。结论表明，本文的研究成果对桩基和桩柱的测量和监测具有一定的参考价值和实用价值。

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引用次数: 0

Prediction method of screw pile bearing capacity under uplift load 上拔荷载作用下螺旋桩承载力预测方法

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-24 DOI: 10.1016/j.sandf.2025.101662

Hongwei Ma , Guoqiang Ma , Weiqiang Zhang

The screw threads continuously distributed along the surface of the pile significantly modify its bearing mechanism, distinguishing it from traditional column piles. Currently, methods for calculating the uplift bearing capacity of screw piles remain underdeveloped. This study presents a calculation method for the uplift bearing capacity of screw piles based on the segmented displacement coordination iterative method, as well as a prediction method for the ultimate uplift bearing capacity using the intersection convergence method. The accuracy of these methods was validated through model and field tests. Using these theoretical calculation and prediction methods, the uplift bearing characteristics and influencing factors of screw piles were analyzed. The results demonstrated that the unique screw thread structure of screw piles significantly enhances their uplift bearing capacity compared to column piles. The P-s curve of screw piles exhibits a slow variation characteristic, and under ultimate bearing state, the shaft resistance is primarily provided by the deeper soil layers. The ultimate uplift bearing capacity of screw piles rises initially and declines as the screw pitch increases, reaching its maximum value when the screw pitch equals the second critical screw pitch. Furthermore, as the internal friction angle increases, screw piles outperform column piles more significantly in uplift capacity.

螺纹沿桩面连续分布，极大地改变了其承载机理，使其区别于传统柱桩。目前，螺旋桩抗拔承载力的计算方法尚不完善。提出了一种基于分段位移协调迭代法的螺旋桩抗拔承载力计算方法，以及一种基于交汇收敛法的螺旋桩抗拔承载力极限预测方法。通过模型和现场试验验证了这些方法的准确性。运用这些理论计算和预测方法，分析了螺旋桩的抗拔承载特性及其影响因素。结果表明：与柱桩相比，螺旋桩独特的螺纹结构显著提高了其抗拔承载力；螺旋桩的P-s曲线呈现缓慢变化特征，在极限承载状态下，桩身阻力主要由较深土层提供。随着螺距的增大，螺旋桩的极限抗拔承载力先上升后下降，当螺距等于第二个临界螺距时达到最大值。随着内摩擦角的增大，螺旋桩的抗拔能力明显优于柱桩。

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引用次数: 0

Geotechnical performance of the Gounokawa River levee during the 2018, 2020, and 2021 flooding events Gounokawa河堤坝在2018年、2020年和2021年洪水事件中的岩土性能

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-24 DOI: 10.1016/j.sandf.2025.101656

Mitsu Okamura , Hirotoshi Mori , Masanori Ishihara , Kenichi Maeda , Naoko Jin-nouchi , Yudai Aoyagi , Shunsuke Shinagawa , Yoshinori Yajima , Kohei Ono

Significant sand ejecta repeatedly appeared during the 2018, 2020, and 2021 flooding events at the Gounokawa River levee in the Shimonohara district of Shimane Prefecture, Japan. Detailed site investigations were conducted, including the recording of a local resident’s eyewitness account, soil borings, electric resistivity tomography, and trench excavations. These methods clarified the event timelines, foundation soil profiles, and origins of the sand ejecta. Topographic changes, analyzed using digital elevation models derived from unmanned aerial vehicle photogrammetry, were used to determine whether backward erosion piping (BEP) had occurred. It was confirmed that high water pressure had propagated through the gravel layer and had broken through the overlying layers. Sand volcanoes formed in locations where an underlying gravel layer had existed and ground surface elevations had been low. The water head difference across the levee, when the sand boiling began, was estimated fairly accurately. This provided a valuable opportunity to verify the validity of the methods used to predict the initiation of sand boiling and BEP. The head difference was the highest in the 2018 event and decreased in the subsequent events. Despite the large amount of sand ejecta, no ground surface subsidence was observed. A grain-size distribution analysis revealed that the underlying gravel contained an unstable sand fraction, and thus, was suffusive. Most of the large amount of sand ejecta is considered to have originated from the gravel layer. Detailed trench wall observations facilitated the development of a scenario describing the ground deformation and sand-clod formation during the repeated flooding events.

在2018年、2020年和2021年的洪水事件中，日本岛根县下野原地区的古野川河堤坝反复出现了大量的沙子喷射。进行了详细的现场调查，包括记录当地居民的目击记录、土壤钻孔、电阻率断层扫描和挖掘壕沟。这些方法阐明了事件时间线、地基土壤剖面和喷砂物的起源。利用无人机摄影测量获得的数字高程模型分析地形变化，以确定是否发生了反向侵蚀管道（BEP）。证实了高压已通过砾石层传播并突破了上覆层。沙火山形成于地下砾石层存在和地表海拔较低的地方。当沙子沸腾时，堤岸上的水头差是相当准确的。这提供了一个宝贵的机会来验证用于预测砂沸腾起始和BEP的方法的有效性。在2018年的比赛中，头部差距最大，在随后的比赛中有所下降。尽管大量喷砂，但未观察到地面沉降。粒度分布分析表明，下伏砾石含有不稳定的砂粒，因此是充满的。大量的喷砂被认为大多来自砾石层。详细的海沟壁观测促进了描述反复洪水事件期间地面变形和沙块形成的情景的发展。

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引用次数: 0

Embankment vibration characteristics using ground motion records and ambient noise measurements, Briones Dam, California 使用地面运动记录和环境噪声测量的路堤振动特性，Briones大坝，加利福尼亚

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-23 DOI: 10.1016/j.sandf.2025.101664

Makbule Ilgac , Adda Athanasopoulos-Zekkos , Chukwuebuka Chukwuemeka Nweke , Olga-Joan Ktenidou , Kyle Peterson , Robert E. Kayen

Investigating the seismic response of earth embankment dams is crucial for assessing the safety of existing dams and guiding new design procedures. The dam fundamental frequency (f₀) is a critical parameter in the dynamic response of dams and can be evaluated using seismic recordings through Horizontal-to-Vertical Spectral Ratio (HVSR) and Standard Spectral Ratio (SSR) methods. This study focuses on assessing the vibration characteristics of Briones Dam, a 78 m-tall earth embankment dam located in the Bay Area in Northern California. First, earthquake-based Horizontal-to-Vertical Spectral Ratio (eHVSR) was estimated by dividing the horizontal records by the vertical components, and the SSR was determined by comparing crest recordings with those from the abutment. Additionally, a field test program was conducted to collect ambient noise measurements at Briones Dam, allowing for the calculation of microtremor-based HVSR. The fundamental frequency was estimated using three empirical methods: mHVSR (0.7–1 Hz), eHVSR (0.9–1.1 Hz), and SSR (1.2 Hz). The median fundamental frequency of the dam is estimated to be approximately 1 Hz at the center of the dam crest. The slight variations among these three methods suggest the need for further investigations that consider the geological and geotechnical conditions of the dam.

研究土堤坝的地震反应对于评估现有坝的安全性和指导新的设计程序至关重要。大坝基频是大坝动力响应的关键参数，可以通过水平-垂直谱比（HVSR）和标准谱比（SSR）方法利用地震记录进行评价。本研究的重点是评估Briones大坝的振动特性，Briones大坝是位于北加州海湾地区的一座78米高的土堤防大坝。首先，将水平分量除以垂直分量，估算出基于地震的水平-垂直谱比（eHVSR），并将波峰记录与桥台记录进行比较，确定SSR。此外，还进行了现场测试程序，以收集Briones大坝的环境噪声测量数据，从而计算基于微震动的HVSR。采用mHVSR （0.7 ~ 1 Hz）、eHVSR （0.9 ~ 1.1 Hz）和SSR (1.2 Hz) 3种经验方法估算基频。大坝的基频中位数估计在坝顶中心约为1hz。这三种方法之间的细微差异表明需要进一步调查，考虑大坝的地质和岩土工程条件。

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引用次数: 0

Levee vulnerability assessment using an integrated unsaturated transient seepage model, sensitivity analysis, and fragility curves 综合非饱和暂态渗流模型、敏感性分析和易损性曲线的堤坝易损性评价

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-23 DOI: 10.1016/j.sandf.2025.101658

E. Ajorlou, M. Ghayoomi

The accelerated changes in climate resulting in more frequent and disruptive floods necessitate broader perspectives of levee vulnerability assessment. This paper aims to advance levee vulnerability curves using global sensitivity analysis to identify critical inputs for developing multi-variable fragilities. This analysis is efficient and effective for skewed data such as extreme precipitation. The study categorizes inputs into geometry, precipitation, and soil characteristics, generating 30,000 scenarios for analysis. A transient unsaturated seepage analysis is conducted to examine different failure modes such as piping, erosion, and overflow, as well as erosion initiation and enlargement time and locations for each scenario. Results show that, in addition to the initial upstream water level and precipitation characteristics, soil properties—such as gravel and clay content, along with water retention parameters—are crucial for developing fragility curves across different soil types. Additionally, comparing fragility curves for historical data and future precipitation projections highlights the importance of integrating these projections into levee risk analysis for the next 30 years. As a practical implication, these fragility curves are applied to calculate failure probabilities for a levee case study. This research would support the integration of levee vulnerability assessments with social factors and stakeholder perspectives which also increases the applicability of fragility functions in flood risk mitigation.

气候的加速变化导致更频繁和破坏性的洪水，需要更广泛的视角来评估堤坝的脆弱性。本文旨在利用全局敏感性分析来推进堤防脆弱性曲线，以识别发展多变量脆弱性的关键输入。这种分析对于极端降水等偏斜数据是高效有效的。该研究将输入分类为几何形状、降水和土壤特征，生成了3万个场景供分析。通过暂态非饱和渗流分析，考察了管道、侵蚀和溢流等不同的破坏模式，以及每种情况下侵蚀的发生和扩大时间和位置。结果表明，除了初始上游水位和降水特征外，土壤性质（如砾石和粘土含量）以及保水参数对不同土壤类型的脆弱性曲线的形成至关重要。此外，比较历史数据和未来降水预测的脆弱性曲线，强调了将这些预测整合到未来30年堤坝风险分析中的重要性。作为实际应用，将这些脆性曲线应用于堤防的破坏概率计算。本研究将支持堤防脆弱性评价与社会因素和利益相关者的观点相结合，提高脆弱性函数在洪水风险缓解中的适用性。

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引用次数: 0

Direct shear testing of frozen soil-structure interface under high normal stress and frozen-thawing conditions 高正应力和冻融条件下冻土-结构界面的直剪试验

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-21 DOI: 10.1016/j.sandf.2025.101660

Bo Wang , Zhi-qiang Liu , Yu Bao

By using an improved DRS-1 high pressure direct shear test system, a series direct shear tests have been carried out under high normal stress and frozen-thawing conditions. Basic shear mechanical characteristics of the interface between the frozen soil and structure are summarized. Effects of normal stress and thawing temperature on the peak shear stress and the initial shear modulus are discussed. The results show that patterns of shear stress-displacement curve will transform gradually from strain softening to strain hardening as the thawing temperature increases. The peak shear strength of frozen soil-structure interface increases significantly with the increase of the normal stress, but decreases with the thawing temperature increases. High normal stress results in larger effective stress in the soil and hinders movement of soil particles on the interface. Increasing of the thawing temperature reduces the adfreezing force on the frozen soil-structure interface.

采用改进型DRS-1型高压直剪试验系统，在高正应力和冻融条件下进行了一系列直剪试验。总结了冻土与结构界面的基本剪切力学特性。讨论了正应力和解冻温度对峰值剪切应力和初始剪切模量的影响。结果表明：随着解冻温度的升高，剪切应力-位移曲线模式由应变软化逐渐转变为应变硬化；冻土-结构界面峰值抗剪强度随正应力的增大而显著增大，但随解冻温度的升高而减小。高的法向应力导致土体有效应力增大，阻碍了土体颗粒在界面上的运动。解冻温度的升高降低了冻土-结构界面的冻融力。

引用次数: 0

Experimental analysis of reinforcement methods for stone column foundations 石柱基础加固方法试验分析

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-18 DOI: 10.1016/j.sandf.2025.101661

Lihua Li , Jinlin Li , Zhiqi Zhan , Yilin Gui , Juqiang Liu

Geosynthetic-reinforced stone columns can significantly improve weak foundations. While previous studies have focused on the individual effects of vertical or horizontal reinforcement, the combined influence of both on stone column foundation performance remains poorly understood. Through physical model tests, this study investigated the effects of various reinforcement methods on the bearing capacity and deformation characteristics of stone column foundations, with a particular focus on the combined reinforcement in enhancing their performance, addressing this research gap. This study encompasses different enhancement lengths, horizontal reinforcement spacings, and combinations of reinforcement methods. Experimental results demonstrate that geosynthetics significantly limit radial deformation and improve the bearing capacity of stone column foundations. Notably, the bearing capacity increases with reduced reinforcement spacing and extended enhancement length. Among all the reinforcement types tested in this study, the full-length (L) vertical reinforcement demonstrated the most significant impact. Additionally, the study examines stress transfer and lateral stress distribution within the stone columns, revealing that as the load increases, the stress ratio at the stone column base and lateral stress rises, with lateral stress peaking at a depth of 2.5D from the surface. This behaviour aligns with the deformation patterns observed in the model tests.

土工合成增强石柱可以显著改善软弱地基。虽然以前的研究主要集中在垂直或水平加固的单个影响上，但两者对石柱基础性能的综合影响仍然知之甚少。通过物理模型试验，研究了各种加固方法对石柱基础承载力和变形特性的影响，重点研究了组合加固对石柱基础承载力和变形特性的影响，弥补了这方面的研究空白。本研究包括不同的加固长度，水平加固间距和加固方法的组合。试验结果表明，土工合成材料能有效地限制石柱基础的径向变形，提高地基承载力。随着加固间距的减小和加固长度的延长，其承载能力有所提高。在本研究测试的所有加固类型中，全长(L)垂直加固的影响最为显著。此外，研究还考察了石柱内部的应力传递和侧应力分布，发现随着荷载的增加，石柱基部应力与侧应力的比值增大，侧应力在距地表2.5D深度处达到峰值。这种行为与模型试验中观察到的变形模式一致。

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引用次数: 0

Seismic response of embankment dams: Shear beam analysis vs field observations 路堤坝的地震反应：剪力梁分析与现场观测

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-15 DOI: 10.1016/j.sandf.2025.101654

Krishna Santhosh , Tadahiro Kishida , George Mylonakis

Embankment dams are critical elements of infrastructure and perform as a system by integrating various components such as foundation, core, shell, filter and spillway. To analyze their entire response, it is important to properly identify the dynamic characteristics of the overall system based on observations. This paper explores the dynamic response of dams using an analytical shear beam analysis under plane-strain conditions, considering the variation of shear modulus and cross-sectional area with height. The governing differential equation is first solved analytically using Bessel functions, and dynamic response parameters are derived for different natural modes. Transfer functions are then derived from the bedrock to the crest for different variations of shear modulus and levels of material damping. Using these analytical results, the study assesses the applicability of the shear beam analysis to 23 embankment dams in Japan, utilizing decades of recorded acceleration time histories to identify their dynamic response and shear wave profiles with height.

堤防大坝是基础设施的重要组成部分，它将基础、核心、壳、过滤器和溢洪道等各种组成部分集成为一个系统。为了分析它们的整个响应，重要的是要根据观察正确地识别整个系统的动态特性。考虑剪切模量和截面积随高度的变化，采用剪力梁解析法研究了平面应变条件下大坝的动力响应。首先利用贝塞尔函数解析求解控制微分方程，推导出不同自然模态下的动力响应参数。然后导出了基岩到波峰的传递函数，用于不同剪切模量和材料阻尼水平的变化。利用这些分析结果，该研究评估了剪切梁分析对日本23个堤防大坝的适用性，利用数十年记录的加速度时程来识别它们的动力响应和剪切波随高度的分布。

引用次数: 0

Reliability based seismic slope failure assessment of a high concrete face rockfill dam close to an active fault zone 靠近活动断裂带的高面板堆石坝地震边坡破坏可靠度评估

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-15 DOI: 10.1016/j.sandf.2025.101653

Ugur Safak Cavus , Murat Kilit

This study assesses the earthquake-induced failure risks of the upstream and downstream slopes of a concrete face dam (CFRD), which is under the influence of a nearby active fault, using the reliability-based analysis method. For this purpose, peak ground accelerations (PGAs) that may occur at the dam site were calculated probabilistically and their contribution to the sliding risks of dam slopes was determined in accordance with the conditional probability theorem. Upstream and downstream slopes of CFRDs are usually conventionally designed as 1.3–1.5H:1V and 1.3–1.6H:1V, respectively throughout the world. Such slope design is considered sufficient for almost every case. The findings of this study are fully applicable and very important for the structural design of all concrete-faced rockfill dams (CFRDs) worldwide. Since, the slope design of CFRDs is similar and usually traditionally (1.3–1.5H; 1V for upstream slope and 1.4–1.6H:1V for downstream slope). However, this study proves that only conventional upstream slope design (1.3–1.5H:1V) can be safe for even very high peak ground accelerations (PGAs) occurring due to a nearby active fault, but contrary to expectations, downstream slope of CFRDs cannot be sufficiently safe and maintain its slope sliding safety when PGAs reach high levels. When the critical PGA level is exceeded, the downstream slope carries the risk of losing its stability with high probability, as emphasized in this study. Therefore, this study provides a new design strategy and extremely important information for dam design engineers which is to design a rather flatter downstream slope such as 1 vertical to 1.8–2.0 horizontal or, instead, to design a downstream rockfill berm supporting conventional design if CFRDs are to be built in high seismic hazard potential areas or close to active faults. Suggested such type of designs will be economical and sufficiently safe.

采用基于可靠度的分析方法，对受附近活动断层影响的混凝土面板坝上下游边坡地震破坏风险进行了评估。为此，根据条件概率定理，对坝址可能出现的峰值地加速度（pga）进行了概率计算，并确定了它们对坝坡滑动风险的贡献。在世界范围内，cfrd的上、下游坡度通常分别设计为1.3 ~ 1.5 h:1V和1.3 ~ 1.6 h:1V。这种坡度设计被认为对几乎所有情况都是足够的。研究结果对世界范围内混凝土面板堆石坝的结构设计具有一定的参考价值。由于cfrd的坡度设计相似，通常采用传统的(1.3-1.5H；上游坡1V，下游坡1.4-1.6H:1V)。然而，本研究证明，对于附近活动断层产生的峰值地加速度（pga），只有传统的上游边坡设计（1.3-1.5H:1V）才能保证安全，而与预期相反，当峰值地加速度达到较高水平时，cfrd下游边坡不能足够安全并保持边坡滑动安全。当超过临界PGA水平时，下游边坡具有高概率失稳风险，这是本研究所强调的。因此，本研究为大坝设计工程师提供了一种新的设计策略和极其重要的信息，即设计一个相当平坦的下游斜坡，如1垂直到1.8-2.0水平，或者在地震高发区或靠近活动断层的地区建造cfrd，而不是设计一个支持常规设计的下游堆石护堤。建议这种设计既经济又足够安全。

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引用次数: 0