Soils and Foundations最新文献_第7页

Hollow cylindrical torsional shear test simulating stress history of sand compaction pile work history 空心圆柱扭剪试验模拟砂压桩工作历程的应力历程

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-05-22 DOI: 10.1016/j.sandf.2025.101628

Hiroshi Yabe , Junichi Koseki

The Sand Compaction Pile (SCP) method is a widely utilized ground improvement technology that enhances the density of the ground by constructing sand piles through penetration and repeated withdrawal/re-driving of a casing pipe. This method is the most widely used liquefaction countermeasure method in Japan.

While the improvement effect of SCP is predominantly attributed to the resultant increase in soil density, recent studies have suggested that the stress history (such as increased lateral pressure and shear history) induced during the SCP work process also contributes significantly to its effectiveness. In order to more accurately reproduce the behavior of the ground during the construction of Sand Piles, the stress history simulating the SCP work process was applied to specimens in hollow cylindrical torsional shear tests, and the effects of the stress history were observed.

The specimens were initially consolidated with a lateral stress ratio of 0.5 (K₀ = 0.5). Subsequently, a stress history including increased lateral stress and cyclic shear stress was applied. Finally, liquefaction resistance was assessed through cyclic loading.

After applying the stress history, an increase in liquefaction resistance was observed in these specimens. This increase was larger than that of specimens subjected only to a lateral stress increase without the shear stress history. This increasing trend persisted even after the lateral stress was reduced following the application of stress history.

Finally, these test results were analyzed to assess the impact of stress history on liquefaction resistance by comparing them with the relationship between relative density and the liquefaction resistance.

砂压桩法（SCP）是一种广泛应用的地基改善技术，它通过钻穿和反复拔/再钻套管来建造砂桩，以提高地基密度。该方法是日本国内应用最广泛的液化对策方法。虽然SCP的改善效果主要归因于由此导致的土壤密度的增加，但最近的研究表明，SCP工作过程中引起的应力历史（如增加的侧压力和剪切历史）也对其效果起着重要作用。为了更准确地再现砂桩施工过程中的地基行为，将模拟SCP工作过程的应力历史应用于空心柱扭剪试验试件，观察应力历史对砂桩施工过程的影响。试件初始固结时，侧向应力比为0.5 （K0 = 0.5）。随后，应用应力史，包括增加的侧向应力和循环剪切应力。最后，通过循环加载对液化抗力进行了评估。施加应力历史后，观察到这些试样的液化阻力增加。这一增幅大于仅受侧向应力增加而不受剪应力历史影响的试件。即使在应用应力历史后降低了侧向应力，这种增加趋势仍然存在。最后对试验结果进行分析，并与相对密度与液化阻力的关系进行比较，评价应力历史对液化阻力的影响。

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引用次数: 0

Deformation characteristics and seepage mechanism of fractured rock mass under triaxial compression process 裂隙岩体三轴压缩变形特征及渗流机理

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-05-22 DOI: 10.1016/j.sandf.2025.101630

Jilu Zhang , Xiaohan Zhou , Xinrong Liu , Yang Kong , Bin Xu , Lojain Suliman

Understanding the gas seepage characteristics within fractured rock masses is of great significance for the prediction and prevention of hazardous gases in underground engineering. The formation is actually under a triaxial non-uniform stress state as a result of geological tectonic forces. Few studies on gas seepage take into account various stress situations. In this study, the flow characteristics of precast fractured rock masses were investigated through laboratory triaxial tests. The research results show that the volume strain of precast fracture changes from expansion to contraction with the decrease of the fracture angle under axial load. The fracture permeability decreases with the increase of axial strain before rock mass failure. After failure, the increase in permeability is not only related to the confining pressure and fracture angle but also has a significant correlation with the failure mode. Considering the triaxial non-uniform stress state, a coupled calculation model for seepage-stress-damage was established, and the calculation method was verified to effectively reflect the deformation and seepage characteristics of fractures. The lateral force on the fracture surface mainly causes the permeability of precast fractures to increase, and the increase extent of fracture permeability is negatively correlated with the fracture angle and elastic modulus.

了解裂隙岩体内气体渗流特征对地下工程有害气体的预测和防治具有重要意义。由于地质构造力的作用，该地层实际上处于三轴非均匀应力状态。很少有关于气体渗流的研究考虑到各种应力情况。本文通过室内三轴试验研究了预制裂隙岩体的流动特性。研究结果表明：在轴向载荷作用下，随着断裂角度的减小，预制构件的体应变由膨胀变为收缩；岩体破坏前，裂隙渗透率随轴向应变的增大而减小。破坏后渗透率的增加不仅与围压、破裂角有关，还与破坏模式有显著的相关性。考虑三轴非均匀应力状态，建立了渗流-应力-损伤耦合计算模型，并验证了该计算方法能有效反映裂隙变形和渗流特征。断裂面上的侧向力主要导致预制裂缝渗透性增加，裂缝渗透性增加的程度与断裂角度和弹性模量呈负相关。

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引用次数: 0

Stochastic estimation of soil hydraulic conductivity utilizing self-organizing map method 基于自组织图法的土壤导电性随机估计

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-05-21 DOI: 10.1016/j.sandf.2025.101601

Kyeongmo Koo, Hyunki Kim

This study proposes an unsupervised Self-Organizing Map (SOM) approach to enhance saturated hydraulic conductivity (k_sat) estimation. Using the extensive FLSOIL database of 6,487 soil samples from Florida, the SOM-based k_sat estimation model is optimized based on map size and feature selection, then compared with seven empirical equations and three supervised machine learning models. Unlike the other methods, the SOM-based approach provides a probabilistic distribution of k_sat, enabling reliability-based design-value determination. Moreover, refining input features particularly by including specific surface area and Kozeny–Carman derived formulas improves accuracy and mitigates bias by the model features, especially in fine-grained soils.

本研究提出一种无监督自组织图（SOM）方法来提高饱和水力导电性（ksat）的估计。利用佛罗里达州FLSOIL数据库中6,487个土壤样本，基于地图大小和特征选择对基于som的ksat估计模型进行了优化，并与7个经验方程和3个监督机器学习模型进行了比较。与其他方法不同，基于som的方法提供了ksat的概率分布，从而实现了基于可靠性的设计值确定。此外，细化输入特征，特别是包括比表面积和Kozeny-Carman推导公式，提高了准确性，减轻了模型特征的偏差，特别是在细粒土壤中。

引用次数: 0

Effects of flocculants on in–situ recycling potential of waste EPB shield muck with residual foams 絮凝剂对含残余泡沫的EPB废渣原位回收潜力的影响

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-05-16 DOI: 10.1016/j.sandf.2025.101625

Yao Lu , Ming Huang , Jim S. Shiau , Fengwen Lai , Liqian Peng

The in–situ recycling technique offers a promising solution for the efficient management of the escalating volumes of waste muck or slurry generated during shield tunneling. While foam is extensively utilized for soil conditioning in earth pressure balance (EPB) tunneling, the effects of organic and inorganic flocculants on the in–situ recycling potential of waste EPB shield muck containing residual foams remain underexplored. To bridge this gap, laboratory experiments were conducted using four flocculants: cationic polyacrylamide (CPAM), nonionic polyacrylamide (NPAM), anionic polyacrylamide (APAM), and polyaluminum chloride (PACL), with an enhanced flocculation and press–filtration apparatus. The defoaming–flocculation–dewatering behavior of waste EPB shield muck was systematically investigated by evaluating key parameters, including residual foam height, defoaming ratio, antifoaming ratio, total suspended solids, turbidity, moisture content, and zeta potential, while accounting for both muck dry mass and fines content. Moreover, the microscopic structure of flocculates and filter cakes was characterized using nanoparticle size analysis and scanning electron microscopy. The experimental results reveal that CPAM exhibits constrained flocculation and dewatering efficiency, primarily attributed to diminished charge neutralization resulting from residual anionic surfactants. In contrast, PACL demonstrates superior dewatering performance compared to NPAM and APAM, but exhibits the lowest flocculation and foam–suppression efficiency. Additionally, a consistent linear negative correlation is identified between the flocculation and dewatering indices of EPB shield muck, independent of the flocculant type, whether organic or inorganic.

就地回收技术为有效管理盾构隧道施工过程中产生的不断增加的废渣或泥浆量提供了一个很有前途的解决方案。虽然泡沫被广泛用于土压平衡（EPB）隧道的土壤调节，但有机和无机絮凝剂对含残余泡沫的EPB盾构垃圾原位回收潜力的影响尚未得到充分研究。为了弥补这一空白，利用阳离子聚丙烯酰胺（CPAM）、非离子聚丙烯酰胺（NPAM）、阴离子聚丙烯酰胺（APAM）和聚氯化铝（PACL）四种絮凝剂进行了实验室实验，并采用了增强絮凝和压滤装置。在兼顾渣土干质量和细粒含量的前提下，通过评价残余泡沫高度、消泡比、消泡比、总悬浮物、浊度、含水率、zeta电位等关键参数，系统研究了EPB盾构渣土的消泡-絮凝-脱水行为。利用纳米粒度分析和扫描电镜对絮凝剂和滤饼的微观结构进行了表征。实验结果表明，CPAM表现出有限的絮凝和脱水效率，主要是由于残留的阴离子表面活性剂减少了电荷中和作用。PACL的脱水性能优于NPAM和APAM，但絮凝抑泡效果较差。此外，EPB屏蔽渣的絮凝与脱水指标之间存在线性负相关关系，与絮凝剂类型（有机或无机）无关。

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引用次数: 0

Performance of screw piles in bio-stabilized slope based on field monitoring and finite element modelling 基于现场监测和有限元模拟的生物稳定边坡螺旋桩性能研究

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-05-05 DOI: 10.1016/j.sandf.2025.101626

Apiniti Jotisankasa , Korakot Tanyacharoen , Susit Chaiprakaikeow , Washirawat Praphatsorn , Sony Pramusandi , Avishek Shrestha , Satoshi Nishimura

A novel slope stabilization technique was recently developed incorporating screw piles with vegetated flapped soilbags. These screw piles are subjected to lateral stress from soil slope and their deformation can be difficult to quantify, given the fluctuating pore-water pressure and heterogeneous soil conditions. This study proposes the use of in-situ spectral analysis of surface waves (SASW) test to estimate the small-strain soil stiffness which can then be factored to calculate the lateral deformation of the pile in finite element modelling based on prescribed pore-water pressure change. A case of bioengineered slope in Kanchanaburi province, Western Thailand was studied, involving field monitoring of pile head tilt, pore-water pressure, suction, and soil moisture over one year. The findings revealed pile head tilt of up to 0.2 degrees in response to rainfall and rise in pore-water pressure and soil moisture over one year period. A series of finite element modelling were performed using factored shear moduli from in-situ SASW test and the monitored pore-water pressure variation to reproduce the amount of pile head tilting as observed in the field during one year. It was revealed that by assuming operational shear modulus ranging between 0.0075 and 0.01 times small-strain soil stiffness, a satisfactory agreement was obtained between field measurement and analysis of pile movement. This findings provides a basis for further studies on performance of bioengineered slope utilizing screw piles.

近年来发展了一种新型的边坡稳定技术，将螺旋桩与植物扑翼土袋相结合。考虑到孔隙水压力的波动和非均质土壤条件，这些螺旋桩受到来自土坡的侧向应力，其变形难以量化。本研究提出使用原位表面波谱分析（SASW）试验来估算小应变土刚度，然后根据规定的孔隙水压力变化，在有限元建模中计算桩的侧向变形。以泰国西部北碧府的一个生物工程边坡为例，进行了为期一年的桩顶倾斜度、孔隙水压力、吸力和土壤湿度的现场监测。研究结果显示，在一年的时间里，随着降雨、孔隙水压力和土壤湿度的上升，桩顶的倾斜度可达0.2度。利用现场SASW试验的剪切模量和监测的孔隙水压力变化进行了一系列有限元建模，以再现一年内现场观察到的桩头倾斜量。计算结果表明，假设操作剪切模量为小应变土刚度的0.0075 ~ 0.01倍，现场实测结果与桩身运动分析结果吻合较好。研究结果为进一步研究螺旋桩生物工程边坡的性能奠定了基础。

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引用次数: 0

Effect of gravity on liquefaction behavior 重力对液化行为的影响

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-05-02 DOI: 10.1016/j.sandf.2025.101617

R. Sukhumkitcharoen , J. Koseki , M. Otsubo , T. Morimoto

Attaining a fully liquefied state with zero effective stress in laboratory element tests is inherently challenging, as this state is typically achieved only in the upper layers of specimens, while the lower layers are still influenced by residual gravitational forces (or self-weight). This challenge has highlighted concerns regarding the potential overestimation of the liquefaction resistance in laboratory-based assessments. In response to this, the present study introduces an advanced bi-axial apparatus designed for testing under both dry and submerged conditions, employing circular plastic rods to enable an analysis with detailed images. Furthermore, discrete element method (DEM) simulations are conducted to replicate analogous environments under varying gravity conditions. The results demonstrate that the configuration of the apparatus, which utilizes lighter materials, significantly diminishes the gravity-induced stress gradient, achieving near-zero effective mean stress in the submerged condition. Both laboratory tests and DEM simulations consistently show similar trends under different gravity settings, such as enhanced contractive behavior, reduced remaining mean stress, and reduced remaining stiffness during the liquefied state in lower gravity environments, resulting in a reduction in liquefaction resistance. These characteristics are attributed to the stimulated loss of inter-particle contacts and an increased number of unstable particles, resulting in weakened void- and contact-based fabrics against cyclic loading under lower gravity conditions. Based on the current testing conditions, a correction factor of approximately 0.6 to 0.8 is advised for bi-axial tests conducted at standard gravity (1g) to convert the liquefaction resistance measured in the laboratory to that suitable for practical applications.

在实验室元件测试中达到零有效应力的完全液化状态本质上是具有挑战性的，因为这种状态通常只在试样的上层实现，而下层仍然受到残余重力（或自重）的影响。这一挑战突出了人们对实验室评估中可能高估液化抗性的担忧。为此，本研究介绍了一种先进的双轴仪器，设计用于在干燥和淹没条件下进行测试，采用圆形塑料棒进行详细图像分析。此外，采用离散元法（DEM）模拟了不同重力条件下的模拟环境。结果表明，该装置采用了较轻的材料，显著减小了重力引起的应力梯度，在水下状态下实现了接近零的有效平均应力。在不同的重力环境下，实验室测试和DEM模拟都一致显示出类似的趋势，例如在低重力环境下，液化状态下的收缩行为增强，剩余平均应力降低，剩余刚度降低，从而导致液化阻力降低。这些特性归因于颗粒间接触的损失和不稳定颗粒数量的增加，导致在较低重力条件下，基于孔隙和接触的织物在循环载荷下变弱。根据目前的测试条件，建议在标准重力（1g）下进行的双轴测试的校正系数约为0.6至0.8，以将实验室测量的液化阻力转换为适合实际应用的液化阻力。

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引用次数: 0

Effect of suffusion and self-filtration on mechanical behavior of well-graded sands 浸渍和自过滤对分级好的砂土力学特性的影响

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-05-01 DOI: 10.1016/j.sandf.2025.101622

Jitrakon Prasomsri , Ratamanee Nuntasarn , Suched Likitlersuang , Akihiro Takahashi

Suffusion in well-graded sands is a significant concern in geotechnical engineering, potentially leading to malfunctions or failures in soil slopes, earth dams, and their foundations. In this paper, two internally unstable well-graded sands of various densities are subjected to seepage tests and consolidated undrained triaxial compression tests using an in-house developed triaxial permeameter. The tests explore the impact of the uniformity coefficient (C_u), initial density, and hydraulic loading amplitude on suffusion. The effect of suffusion on the undrained mechanical behavior is investigated. The results indicate that specimens with smaller C_u and higher density exhibit a larger onset hydraulic gradient for suffusion, resulting in a smaller eroded mass and fewer changes in permeability. Increasing the hydraulic loading amplitude leads to a larger eroded mass and more changes in permeability. Compared to non-eroded specimens, eroded specimens exhibit reduced shear strength and stiffness during compression tests, increased strain-softening, and contractive behavior. A post-test particle-size distribution analysis shows a significant increase in particles smaller than 0.425 mm within the eroded specimens’ midsection, in contrast to a reduction in the top section. This leads to clogging in the midsection, due to seepage, and a non-uniform particle-size distribution throughout the specimens. Suffusion also causes a decrease in mean effective stress at the critical state in the specific volume-mean effective stress plane.

在岩土工程中，分级良好的砂土的渗透是一个重要的问题，可能导致土坡、土坝及其基础的故障或破坏。本文采用自行研制的三轴渗透率仪，对两种不同密度的内部不稳定级配良好砂进行了渗流试验和固结不排水三轴压缩试验。试验探讨了均匀系数（Cu）、初始密度和水力加载幅值对扩散的影响。研究了扩散对不排水力学性能的影响。结果表明：Cu越小、Cu密度越高的试样，其渗流起始水力梯度越大，侵蚀质量越小，渗透率变化越小；水力加载幅值越大，侵蚀体越大，渗透率变化越大。与非侵蚀试样相比，侵蚀试样在压缩试验中表现出较低的抗剪强度和刚度，应变软化和收缩行为增加。试验后粒度分布分析表明，侵蚀试样中部小于0.425 mm的颗粒显著增加，而顶部颗粒减少。这导致在中部堵塞，由于渗透，和一个不均匀的颗粒尺寸分布在整个试样。在比容-平均有效应力平面的临界状态下，扩散也会导致平均有效应力的减小。

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引用次数: 0

Bayesian network based probabilistic approach for uncertainty analysis of earthquake induced landslides 基于贝叶斯网络的地震诱发滑坡不确定性分析的概率方法

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-04-23 DOI: 10.1016/j.sandf.2025.101620

Tanmoy Das, Deepankar Choudhury

In this study, a unique approach is used to calculate the likelihood of the safety factor and permanent displacement of natural slopes under earthquake shaking. The proposed approach was constructed using probabilistic modeling of landslide instability based on the Bayesian Network technique. First, the pseudo-static factor of safety was computed, considering it an uncertain parameter. Then, the permanent displacement of failure mass was estimated through probabilistic analysis considering the effect of critical and peak horizontal acceleration. In the process of probabilistic analysis, soil and slope properties (cohesion, friction angle, unit weight, slope angle, and failure depth) and peak horizontal acceleration were considered as random variables distributed as normal and exponential functions, respectively. To illustrate the applicability of the proposed approach, a hypothetical infinite slope was adopted from past literature. The results showed that due to the event of an earthquake, the slope might experience permanent displacement. Finally, based on the variation of permanent displacement, the likelihood of landslide occurrences was estimated. Validation of the study was established by comparing the outcomes with the results obtained from the multivariate probabilistic approach, first-order reliability method, and Monte Carlo simulation. To demonstrate the practical applicability of the proposed framework, a case study of earthquake-induced landslides was taken to estimate the factors of safety and permanent displacement probabilistically. The methodology presented in this study would lead to an estimation of landslide failures by taking uncertainties into account, which would increase the safety of city dwellers.

本文采用一种独特的方法来计算地震作用下天然边坡的安全系数和永久位移的似然。该方法采用基于贝叶斯网络技术的滑坡失稳概率建模方法。首先，考虑拟静力安全系数为不确定参数，计算拟静力安全系数；然后，考虑临界和峰值水平加速度的影响，通过概率分析估计了破坏体的永久位移；在概率分析过程中，将土体和边坡特性（黏聚力、摩擦角、单位重量、坡角、破坏深度）和峰值水平加速度分别视为随机变量，分别以正态函数和指数函数的形式分布。为了说明所提出的方法的适用性，从过去的文献中采用了一个假设的无限斜率。结果表明，由于地震的发生，边坡可能发生永久位移。最后，根据永久位移的变化，估计了滑坡发生的可能性。通过将结果与多元概率方法、一阶可靠性方法和蒙特卡罗模拟的结果进行比较，建立了研究的有效性。为了证明该框架的实际适用性，以地震诱发的滑坡为例，对安全系数和永久位移系数进行了概率估计。本研究中提出的方法将通过考虑不确定性来估计滑坡破坏，这将增加城市居民的安全。

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引用次数: 0

Spatial distribution estimation by considering the cross-correlation between components with indirect data using Gaussian process regression 利用高斯过程回归法，通过考虑间接数据各组成部分之间的交叉相关性进行空间分布估计

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-04-22 DOI: 10.1016/j.sandf.2025.101624

Yuto Tsuda , Ikumasa Yoshida , Shinichi Nishimura

Generally, soil properties are measured only at limited locations. To rationally estimate the spatial distribution of soil properties, it is preferable to effectively use all available measurement data, including indirect data. We propose a Gaussian process regression with multiple random fields that considers the cross-correlation between one of the random fields of direct data and indirect data, and show the application to simulated data and actual measured data. In the application, the direct data are of CPT tip resistance (qc), which was obtained within a narrow area, and the indirect data are of shear wave velocity (Vs) obtained by surface wave exploration, which were obtained over a wide area. We estimate the spatial distribution of qc from the limited qc and wide area Vs data. The estimation accuracy of the proposed method is evaluated by cross-validation, and its effectiveness is discussed.

一般来说，土壤性质只在有限的地点测量。为了合理估计土壤性质的空间分布，最好有效地利用所有可获得的测量数据，包括间接数据。我们提出了一种考虑直接数据和间接数据的一个随机场之间相互关系的多随机场高斯过程回归，并展示了它在模拟数据和实际测量数据中的应用。在应用中，直接数据是在狭窄区域内获得的CPT尖端阻力（qc），间接数据是在广泛区域内获得的面波勘探获得的横波速度（Vs）。我们从有限的qc和广域的v数据中估计qc的空间分布。通过交叉验证对该方法的估计精度进行了评价，并对其有效性进行了讨论。

引用次数: 0

Long-distance flow mechanism of gentle slopes under seepage due to liquefaction-induced water film during 2018 Sulawesi earthquake, Indonesia 2018年印尼苏拉威西地震液化水膜作用下缓坡长距离渗流机制

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-04-19 DOI: 10.1016/j.sandf.2025.101611

T. Kokusho , T. Sawada , H. Hazarika , Y. Isobe

Unprecedented liquefaction-induced slope failure occurred during the 2018 Indonesian Sulawesi earthquake in which more than 2000 people were killed by sliding debris flows in very gentle slopes with a 2 % gradient. In order to clarify the mysterious mechanism of how long-distance debris flows could occur on such gentle slopes, transient seepage analyses were conducted focusing on the impact of a thin water film of a limited horizontal length which was supposed to emerge during liquefaction in a layered soil profile beneath a low-permeability cap layer of the slope influenced by stationary seepage. Consequently, the water film was found to play a key role in transmitting higher pressure head to the tip at a lower elevation with a marginal head loss, leading to the downslope extension of the water film and associated boiling failure in the cap layer. The water film that formed during liquefaction was significant in realizing the long-distance flows down the gentle slopes during and even after liquefaction as long as the water film was sustained. This mechanism should be newly recognized as a serious threat to a society due to liquefaction in gentle slopes during strong earthquakes.

2018年印度尼西亚苏拉威西岛地震发生了前所未有的液化引起的边坡破坏，2000多人死于坡度为2%的非常缓坡上的滑动泥石流。为了弄清这种缓坡上长距离泥石流发生的神秘机制，我们进行了瞬态渗流分析，重点研究了受固定渗流影响的边坡低渗透帽层下分层土壤剖面液化过程中出现的有限水平长度的薄水膜的影响。因此，水膜在将高压水头以较小的水头损失传递到较低高度的顶部方面发挥了关键作用，导致水膜的下坡延伸和相应的帽层沸腾失效。液化过程中形成的水膜对实现液化过程中和液化后沿缓坡的长距离流动具有重要意义，只要水膜持续存在。这种机制应该被重新认识到是对社会的严重威胁，因为在强震期间，缓坡会液化。

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引用次数: 0