Engineering Geology最新文献_第8页

Dynamic analysis of multi-block rockfalls using improved 3-D discontinuous deformation analysis: Effect of coefficient of restitution 基于改进三维非连续变形分析的多块岩崩动力学分析：恢复系数的影响

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-11 DOI: 10.1016/j.enggeo.2025.107910

Changze Li , Gonghui Wang , Guangqi Chen , Jingyao Gao , Pengcheng Yu , Xinyan Peng

Rockfalls are a frequent hazard in mountainous regions, posing significant risks to both people and infrastructure due to their high velocity, mass, and energy. However, understanding the dynamics of multi-block systems remains challenging because of their inherent complexity, complicating accurate predictions. This study focuses on the critical role of the coefficient of restitution (COR) in governing the dynamic behavior of multi-block rockfalls. To address this, an improved three-dimensional discontinuous deformation analysis (3-D DDA) method is developed and applied to simulate energy dissipation during collisions in multi-block rockfalls. The improved 3-D DDA is validated through comparisons with theoretical and experimental rockfall models. Using this method, simulations of multi-block rockfalls with varying COR values are conducted to examine their influence on rockfall dynamics and deposition patterns. The analysis also incorporates friction angle to explore its interaction with the block-ground COR. Results reveal that in high-COR path materials, such as rock slopes, the sliding friction coefficient becomes a more influential factor in determining rockfall runout distances. Additionally, the integration of the 3-D DDA method with 3-D scanning technology enables simulations using real-world block geometries, facilitating the investigation of block sphericity effects. The proposed method offers a robust framework for analyzing multi-block rockfall mechanisms, improving both prediction accuracy and post-failure assessments.

岩崩是山区常见的灾害，由于其高速度、高质量和高能量，对人和基础设施都构成了重大风险。然而，由于其固有的复杂性，理解多区块系统的动态仍然具有挑战性，使准确的预测复杂化。本文研究了恢复系数（COR）在控制多块岩崩动力行为中的关键作用。为了解决这一问题，提出了一种改进的三维非连续变形分析方法，并将其应用于多块岩崩碰撞过程中的能量耗散模拟。通过与理论和实验岩崩模型的对比，验证了改进的三维DDA算法。利用该方法对不同COR值的多块岩崩进行了模拟，研究了它们对岩崩动力学和沉积模式的影响。分析还纳入了摩擦角，以探索其与块地COR的相互作用。结果表明，在高COR路径材料中，如岩石边坡，滑动摩擦系数成为决定岩崩跳动距离的更重要因素。此外，3-D DDA方法与3-D扫描技术的集成使模拟使用真实的块几何形状，便于块球形效应的研究。该方法为分析多块岩崩机制提供了一个强大的框架，提高了预测精度和破坏后评估。

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引用次数: 0

A rapid unsaturated infiltration prediction method for slope stability analysis considering uncertainties: Deep operator networks

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-11 DOI: 10.1016/j.enggeo.2024.107886

Peng Lan , Jinsong Huang , Jingjing Su , Shuairun Zhu , Jie Chen , Sheng Zhang , Shui-Hua Jiang

Slope stability analysis is closely related to the quantification of uncertainties in unsaturated infiltration behavior. These uncertainties arise from both internal factors, such as spatial variability in soil physical properties, and external factors, like stochastic variability in rainfall intensity. Although random-field numerical methods provide a reliable way to quantify such uncertainties, their substantial computational demands present an obvious drawback. To address this limitation, we develop a novel data-driven surrogate model using deep operator networks (DeepONet), and construct a direct mapping between the uncertain factors and their induced responses in unsaturated-slope infiltration fields. Unlike conventional deep neural networks that approximate relationships between variables, DeepONet primarily focuses on approximating relationships between functions, learning operator mappings between them (uncertain factors and their responses in slope stability). Three unsaturated infiltration scenarios under uncertain conditions are given to evaluate the performance of DeepONet. The results demonstrate the effectiveness of applying DeepONet for rapid and accurate prediction of unsaturated infiltration behavior in slopes. DeepONet exhibits an advantage in computational speed for uncertain slope stability problems, outperforming traditional numerical solvers by several orders of magnitude without requiring additional repeat training.

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引用次数: 0

Model test study of soil grouting effect on shield tunnel longitudinal structural behavior

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-11 DOI: 10.1016/j.enggeo.2025.107912

Yu-shan Hua, Dong-ming Zhang, Hong-wei Huang

Soil grouting has been widely applied in many shield tunnel settlement rehabilitation projects worldwide. However, the effectiveness of grouting on tunnel longitudinal performance largely relies on experience and field detection. In this study, a self-designed grouting model system was used to conduct a series of tests investigating soil and structural behaviors during grouting. Various grouting parameters, including burial depth, grouting volume and times, and grouting pressure, were analyzed to assess their impact on tunnel mechanical deformation. Results indicate that slurry diffusion in sand involves both compaction and fracture mechanisms, and the compaction of the surrounding soil diminishes along the expansion direction of the slurry vein. Reducing burial depth, increasing grouting volume and pressure, and employing continuous grouting all can enhance the effectiveness of settlement reduction. However, these reductions in settlement are often associated with adverse circumferential joint deformations, particularly joint dislocation. Multiple discontinuous grouting and shallow buried strata would introduce more disturbances, causing greater variation in joint deformation and more significant dissipation of additional stress after grouting. These findings provide valuable references for optimizing grouting practices in similar engineering applications.

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引用次数: 0

A multi-method approach in the physical and mechanical assessment of lava rocks with distinct microstructure 具有不同微观结构的火山岩物理力学评价的多方法方法

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-10 DOI: 10.1016/j.enggeo.2025.107907

Maria Luísa Pereira , Lucia Pappalardo , Gianmarco Buono , Nora Cueto , Carmen Vázquez-Calvo , Rafael Fort , Matilde Costa e Silva , Isabel Fernandes , Vittorio Zanon , Paulo Amaral

Volcanic rocks are common geological-geotechnical units with several heterogeneities. Their microstructural influence on deformation remains unexplored in engineering contexts. This study presents a comprehensive assessment of lava rocks ranging from basalts to trachytes, comprising massive and vesicular textures, varying degrees of fracturing and distinct pore size distributions. A multi-method approach combining X-ray microtomography, thin section analysis, and mercury intrusion porosimetry allowed to characterise the pore space and crystals at distinct scales and define fluid transport mechanisms. Digital rock physics allowed for determining absolute permeability and porosity and developing novel pore network models. Mechanical tests during time-resolved 3D X-ray imaging allowed for fracture development visualisation on varied lavas. Additional physical and mechanical properties were determined following international standards.

Results show that porosity (4 %-29 %) is primarily influenced by pore size and connectivity rather than vesicle shape or orientation. Macrovesicles (> 15 μm) are sub-spherical, while low sphericity indicates vesicle coalescence and fractures, which reduce rock strength and stiffness more than the feldspar content. Vesicular specimens (effective porosities above 10 %) have a permeability controlled by the vesicle size, while the number of microcracks and porosity define permeability in both massive and fractured lavas.

This study highlights the importance of microstructural assessment as a foundation for geological and geotechnical investigations, enabling informed material selection and building conservation strategies. The adopted analysis strategy, which combines techniques often used separately, has proven effective and is suggested for extending to the study of other complex materials.

火山岩是常见的地质-岩土单元，具有多种非均质性。它们的微观结构对变形的影响在工程环境中仍未被探索。本文对玄武岩到粗叶岩的火山岩进行了综合评价，包括块状和泡状结构，不同程度的压裂和不同的孔径分布。结合x射线显微断层扫描、薄片分析和汞侵入孔隙度测定的多方法方法可以在不同尺度上表征孔隙空间和晶体，并确定流体输送机制。数字岩石物理可以确定绝对渗透率和孔隙度，并开发新的孔隙网络模型。在时间分辨率三维x射线成像期间进行的力学测试允许对不同熔岩的裂缝发育进行可视化。其他物理和机械性能是按照国际标准确定的。

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引用次数: 0

Initiation and motion of rainfall-induced loose fill slope failure: New insights from the MPM 降雨诱发松散填土边坡崩塌的起因和运动：来自 MPM 的新见解

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-10 DOI: 10.1016/j.enggeo.2025.107909

Z.Q. Zhan , C. Zhou , Y.F. Cui , C.Q. Liu

Loose fill slopes are prevalent worldwide, and their failure during rainstorms is frequently documented. While existing studies have primarily focused on the initiation of such failures, the post-failure motion of rainfall-induced loose fill slope failures has rarely been explored. This study addresses this knowledge gap by investigating both the initiation and subsequent motion of rainfall-induced loose fill slope failures. To achieve this goal, a hydro-mechanical coupled MPM model was utilized to back-analyze the catastrophic 1976 Sau Mau Ping landslide in Hong Kong and conduct parametric studies. From an engineering perspective, the contractive behaviour of loose coarse-grained soil, which induces positive excess pore water pressure and leads to Bishop's stress reduction and a drop in strength, is a major factor contributing to this landslide. The entire failure process can be classified into three phases with different failure modes: local slide, global slide, and flow-like slide, closely related to the soil stress path. The computed results closely match the field measurements on various aspects, including the landslide zone, mobilized volume, and runout distance. The parametric studies reveal that the landslide zone, mobilized soil volume, and final runout distance decrease with a lower value of dilation angle and a smaller critical state plastic deviatoric strain. Conversely, in the case of a constant SWRC, there tends to be an overestimation of these parameters. It is therefore important to consider soil contraction and its influence on hydro-mechanical behaviour.

松散的填土斜坡在世界范围内普遍存在，它们在暴雨期间的破坏经常被记录下来。虽然现有的研究主要集中在这种破坏的开始，但很少探讨降雨诱发的松散填土边坡破坏的破坏后运动。本研究通过调查降雨引起的松散填土边坡破坏的开始和随后的运动来解决这一知识差距。为了实现这一目标，利用水-力耦合MPM模型对1976年香港秀茂坪灾难性滑坡进行了反分析，并进行了参数化研究。从工程角度来看，松散的粗粒土的收缩行为，引起正超孔隙水压力，导致Bishop应力减小和强度下降，是导致该滑坡的主要因素。整个破坏过程可划分为与土体应力路径密切相关的局部滑动、整体滑动和流状滑动三个阶段，并具有不同的破坏模式。计算结果在滑坡区域、动员体积、跳动距离等方面与现场实测结果吻合较好。参数化研究表明，随着剪胀角值的减小和临界状态塑性偏应变的减小，滑坡面积、动土体积和最终跳动距离减小。相反，在SWRC恒定的情况下，这些参数往往会被高估。因此，考虑土壤收缩及其对水力学行为的影响是很重要的。

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引用次数: 0

Temporal stability and risk analysis of soil slopes subject to rainfall: The influence of heterogeneity

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-10 DOI: 10.1016/j.enggeo.2024.107895

Cheng Qian , Yajun Li , Philip J. Vardon , Wei Shao , Jiahe Song , Bin Zhang , Nengxiong Xu

Evaluating the temporal stability and risk of unsaturated soil slopes during rainfall is essential for early warning and emergency response to landslides. However, limited research has been conducted on the transition timing of sliding mechanisms, instability/failure time and the integration of sliding consequences into quantitative risk assessment. In order to extend the research in this field, the Random Finite Element Method (RFEM) is used in this paper to investigate the influence of spatial variability of hydraulic properties (related to the fundamental parameter porosity) on the temporal stability and risk of soil slopes subject to rainfall. The findings indicate that the advancing speed of the wetting front is more rapidly in zones with low porosity than that in zones with high porosity. As rainfall progresses, the sliding mechanism of the slope shifts from deep sliding to shallow sliding. The homogeneous case tends to underestimate the rise in groundwater levels, leading to an overestimation of slope stability. Hydraulic boundary conditions significantly affect slope stability, making it crucial to consider horizontal (or near the toe of the slope) drainage conditions in practical applications. Additionally, the time of instability/failure predicted in the homogeneous case may be delayed compared to the actual conditions. Both probability of instability/failure and risk increase with continued rainfall. Compared to scenarios where the spatial variability of internal friction angle is not considered, the probability of instability/failure and risk will be higher when the spatial variability of internal friction angle is additionally considered. Risk-based assessment can define the risk levels, reflecting the severity of sliding consequences. Furthermore, the Malin slope failure record from the Chibo region of India is used to validate the effectiveness of the proposed approach. The probabilities of slope failure align well with actual observations, and the risk-based assessment provides additional information into the Malin landslide. This paper proposes a general model for studying the performance of heterogeneous slopes subject to rainfall, providing valuable guidance for landslide early warning systems and the scope and timing of emergency measures taken.

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引用次数: 0

Dynamic mechanism triggering the catastrophic Xinjing Landslide in Alxa, Inner Mongolia, China 内蒙古阿拉善新京特大滑坡的动力机制

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-10 DOI: 10.1016/j.enggeo.2025.107911

Fangpeng Cui , Chen Xiong , Qiang Wu , You Zhou , Chengheng Hou , Linfeng Fan , Miao Liu , Hao Xu , Xu Pan

Few studies have been conducted on the deformation and failure behaviors of open-pit slopes exposed to the combined impacts of mining blasting and geostructure, particularly those generated purely by mining blasting. This study proposes an integrated approach, specifically including dynamic modeling using a novel mesh generation strategy, to systematically reveal the progressive deformation, critical failure and long runout of a catastrophic landslide that occurred on 22 February 2023 at the Xinjing open pit mine, Inner Mongolia. The results show that the internal factors responsible for the landslide include lithological setting, micro-landform, geological structure, and rock mass structure. An unidentified pre-existing reverse fault served as the key internal factor. On the other hand, the external trigger for the landslide was the blasting operation near the slope foot, which exacerbated the fragmentation and ultimately led to the critical failure and overall slide along the fault plane. The landslide manifested as an advancing rock wedge slide. The failure initiated from the back and then the middle parts of the original slope, which pushed the front and foot to trigger the subsequent creep. The following runout was controlled by the topographic relief of the open-pit bottom and consisted of five stages: critical failure, disintegration and fragmentation, debris avalanche, collision and surging up, and accumulation and self-stabilization. Finally, the blasting vibration was identified as the sole trigger for the Xinjing landslide, which had been subjected to the prolonged impact of the reverse fault. This study highlights how important it is to account for the sole effect of mining blasting when assessing the stability of open-pit slopes, which can mitigate the failure risk.

对于露天边坡在采矿爆破和土工结构共同作用下的变形破坏行为，特别是单纯的采矿爆破作用下的变形破坏行为研究较少。本研究提出了一种综合方法，特别是使用一种新的网格生成策略进行动态建模，系统地揭示了2023年2月22日内蒙古新京露天矿发生的灾难性滑坡的渐进变形、临界破坏和长跳。结果表明，造成滑坡的内部因素包括岩性环境、微地貌、地质构造和岩体结构。一个未识别的预先存在的反向断层是关键的内部因素。另一方面，坡脚附近的爆破作业是滑坡发生的外部触发因素，爆破作业加剧了边坡破碎，最终导致沿断裂面发生临界破坏和整体滑动。滑坡表现为向前推进的楔岩滑坡。破坏首先发生在原边坡的后部，然后是中间部分，这推动了前坡和坡脚，引发了随后的蠕变。接下来的跳动受露天矿底部地形起伏控制，分为临界破坏阶段、崩解破碎阶段、岩屑雪崩阶段、碰撞涌动阶段和堆积自稳定阶段五个阶段。最后确定爆破振动是新井滑坡长期受逆断层影响的唯一触发因素。该研究强调了在评估露天矿边坡稳定性时考虑采矿爆破的单一影响的重要性，这可以降低破坏风险。

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引用次数: 0

Research on hydraulic fracture propagation and interwell interference mechanisms during multi-well pad fracturing in shale reservoirs 页岩储层多井块压裂水力裂缝扩展及井间干扰机理研究

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-09 DOI: 10.1016/j.enggeo.2025.107905

Bo Zhang , Tiankui Guo , Ming Chen , Linrui Xue , Yunpeng Wang , Haiyang Wang , Jiwei Wang , Zhanqing Qu , Wentao Ma

Shale reservoirs have unfavourable characteristics such as strong heterogeneity and vertical multiple layers. Multi-well pad fracturing is a highly efficient fracturing technology that can achieve stereoscopic reservoir exploitation. Previous studies usually focused on 2D models, but they cannot simultaneously achieve longitudinal and vertical propagation. Through continuum-discontinuum element method (CDEM), a CDEM-HM3D model is established to investigate the fracture propagation mechanism under well interference and the influences of well spacing, well layout, and fracture spacing on multi-well pad fracturing in a field-scale shale reservoir model with bedding planes. Results show the fracturing performance from preferential fracturing in the lower-stress layer is superior to that in the high-stress layer. The former fully utilizes interwell interference to avoid fracture penetration in the high-stress layer, which is conducive to the safe and independent development of the target reservoir. Compared with staggered well fracturing, stacked well fracturing can more effectively compensate for the reconstruction difference between different layers and activate more bedding area, but the fracture control range decreases. Under the premise of no fracture penetration, increasing the well spacing properly can expand the fracture control range and achieve optimal fracturing performance. An optimal fracture spacing can prevent fracture penetration in the high-stress layer and enlarge the transverse fracture control range, thereby exploiting more resources between fractures. The results can provide theoretical guidance for the efficient development of shale reservoirs.

页岩储层具有非均质性强、垂向多层等不利特征。多井座压裂是一种能够实现储层立体开发的高效压裂技术。以往的研究多集中在二维模型上，无法同时实现纵向和纵向传播。采用连续-非连续单元法（CDEM），建立CDEM- hm3d模型，研究井间干扰下裂缝扩展机理，以及井距、井布设、裂缝间距对具有层理面的页岩储层多井台压裂的影响。结果表明：低应力层优先压裂优于高应力层优先压裂；前者充分利用井间干扰，避免高应力层裂缝穿透，有利于目标储层安全独立开发；与交错井压裂相比，叠井压裂可以更有效地补偿不同层间的改造差异，激活更多的层理面积，但裂缝控制范围减小。在无裂缝侵彻的前提下，适当加大井距可以扩大裂缝控制范围，达到最佳压裂效果。最佳裂缝间距可以防止高应力层裂缝侵彻，扩大横向裂缝控制范围，从而开发更多缝间资源。研究结果可为页岩储层高效开发提供理论指导。

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引用次数: 0

Effects of loading paths and initial densities on mechanical response and gradation evolution of calcareous sand 加载路径和初始密度对钙质砂力学响应及级配演化的影响

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-09 DOI: 10.1016/j.enggeo.2025.107908

Jiarui Chen , Yaolan Tang , Jianhong Ye , Chunshun Zhang , Zhenghong Lin , Congying Li , Wei Wei , Jie Dong

Calcareous sand, a distinctive granular material in geotechnical engineering, has garnered significant interest due to its irregular particle shapes, internal porosity, susceptibility to breakage, and critical role in island and offshore construction. Despite its importance, the influence of loading paths on its mechanical behavior and particle breakage remains underexplored. This study addresses this gap through an extensive experimental program, including isotropic consolidation and both drained and undrained triaxial compression tests, systematically varying loading paths and initial densities. The findings demonstrate that the strength and deformation characteristics of calcareous sand are profoundly affected by loading paths, initial densities, and particle breakage. A novel breakage evolution model is proposed, effectively capturing gradation changes under diverse testing conditions. Furthermore, the study quantifies the impacts of these factors on critical mechanical properties, including peak friction angle, dilatancy, secant modulus, and critical state parameters. These results provide a robust theoretical foundation for the development of constitutive models that integrate particle breakage and initial density effects. The insights are essential for optimizing geotechnical designs, enhancing stability, and improving infrastructure reliability in coastal and marine environments, particularly in island and reef development projects.

钙质砂是岩土工程中一种独特的颗粒材料，由于其不规则的颗粒形状、内部孔隙度、易破碎性以及在岛屿和近海建设中的关键作用，已经引起了人们的极大兴趣。尽管它很重要，但加载路径对其力学行为和颗粒破碎的影响仍未得到充分研究。本研究通过广泛的实验程序解决了这一差距，包括各向同性固结、排水和不排水三轴压缩试验、系统地改变加载路径和初始密度。研究结果表明，加载路径、初始密度和颗粒破碎程度对钙质砂的强度和变形特性有较大影响。提出了一种新的断裂演化模型，能有效地捕捉不同试验条件下的级配变化。此外，研究还量化了这些因素对临界力学性能的影响，包括峰值摩擦角、剪胀率、割线模量和临界状态参数。这些结果为建立综合颗粒破碎和初始密度效应的本构模型提供了坚实的理论基础。这些见解对于优化岩土设计、增强稳定性以及提高沿海和海洋环境（特别是岛屿和珊瑚礁开发项目）中基础设施的可靠性至关重要。

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引用次数: 0

Assessment of near-surface undrained shear strength of soft seabeds with free fall cone penetrometer testing in the northern Baltic Sea 波罗的海北部软基近地表不排水抗剪强度的自由落体锥贯入试验评价

IF 6.9 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-01-09 DOI: 10.1016/j.enggeo.2025.107906

Maarit Saresma , David J. White , Debasis Mohapatra , Saeideh Mohammadi , Wojciech Sołowski , Leena Korkiala-Tanttu , Joonas J. Virtasalo , Susan Gourvenec

Free fall cone penetrometer testing (FFCPT) allows for efficient site reconnaissance and soft seabed undrained shear strength (s_u) assessment in a shallow water environment. The FFCPT is a particularly useful tool for near-surface characterization for cable route assessment associated with offshore renewable developments. This study presents results from an in-situ FFCPT, seismoacoustic survey and sediment coring campaign in a nearshore site in the Gulf of Finland, northern Baltic Sea. An extended FFCPT interpretation model has been applied, including friction on the shaft (as well as tip resistance), rate dependency and soil buoyancy. The derived FFCPT profiles are repeatable at a given location, while the shapes of the s_u profiles capture different depositional environments. The derived dynamic FFCPT s_u is lower than measured in the laboratory by fall cone and triaxial tests. This is potentially due to hydrodynamic drag reducing the FFCPT terminal velocity and soil drag affecting the penetration depth and dynamic s_u; and due to the reconstituted nature of the laboratory samples and very low stress levels being considered that are difficult to achieve in the laboratory. The magnitude of derived s_u and characteristic shapes in the FFCPT profiles enable ground-truthing the interpretation of seismoacoustic profiles. This study contributes to the evidence base supporting the FFCPT as a valuable supplement, or to partially replace sediment coring and laboratory measurements, for offshore site assessment.

自由落体锥入度仪测试（FFCPT）可在浅水环境中进行高效的现场勘察和软海床排水抗剪强度（su）评估。自由落体锥入度仪是一种特别有用的工具，可用于近海可再生能源开发相关电缆线路评估的近表层特征描述。本研究介绍了在波罗的海北部芬兰湾一个近岸地点进行的原位 FFCPT、地震声学勘测和沉积物取芯活动的结果。应用了扩展的 FFCPT 解释模型，包括轴上的摩擦力（以及顶端阻力）、速率依赖性和土壤浮力。得出的 FFCPT 剖面在特定地点具有可重复性，而 su 剖面的形状则反映了不同的沉积环境。得出的动态 FFCPT su 值低于在实验室通过落锥试验和三轴试验测得的值。这可能是由于流体动力阻力降低了 FFCPT 的末端速度，土壤阻力影响了穿透深度和动态 su，以及由于实验室样品的重组性质和考虑的应力水平非常低，在实验室中很难实现。FFCPT 剖面中的推导 SU 值和特征形状有助于对地震声剖面的解释进行地面实况验证。这项研究为支持 FFCPT 作为近海场地评估的重要补充或部分替代沉积物取芯和实验室测量的证据基础做出了贡献。

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引用次数: 0