Computers and Geotechnics最新文献_第5页

Study on the heat transfer characteristics of cemented backfill heat exchangers with a horizontally penetrating rough fracture under groundwater advection 地下水平流条件下具有水平贯通粗糙断裂的胶结回填热交换器的传热特性研究

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-11 DOI: 10.1016/j.compgeo.2024.106792

One of the most effective methods for geothermal energy extraction in deep mine stopes is the installation of heat exchange tubes within cemented backfill bodies. However, the complex underground environment can cause fracture in the backfill, which may negatively affect the geothermal extraction performance, especially in the presence of groundwater flow. This study establishes a three-dimensional seepage and heat transfer coupling model of cemented backfill heat exchangers with horizontal penetrating rough fractures via a finite element software platform. The model employs the Monte Carlo method combined with linear filtering to generate a rough fracture. The findings demonstrate that for fracture apertures ranging from 0 to 0.3 mm, the predominant mechanism of heat transfer is thermal conduction, with a negligible contribution from groundwater flow. However, as apertures expand from 0.3 mm to 2 mm, groundwater flow significantly enhances heat transfer, stabilizing beyond 2 mm. Increased fracture roughness at a 0.2 mm aperture does not enhance the heat recovery performance of the heat exchange tubes, but at a 4 mm aperture, a strong positive correlation between roughness and heat transfer is observed. Thus, narrow fractures can be treated as smooth, whereas roughness must be considered for wider fractures. The interaction between fracture flow and Darcy seepage increases with increasing groundwater hydraulic head, resulting in a notable improvement in the heat extraction performance of the heat exchange tube. When the relative position transitions from 0.75 °C to 0 °C, the outlet water temperature of the heat exchanger tube increases by approximately 9 °C.

在深矿井井口提取地热能的最有效方法之一是在水泥回填体中安装热交换管。然而，复杂的地下环境会导致回填体断裂，从而对地热提取性能产生负面影响，尤其是在存在地下水流的情况下。本研究通过有限元软件平台，建立了具有水平贯穿性粗糙裂缝的胶结回填热交换器的三维渗流和传热耦合模型。该模型采用蒙特卡洛法结合线性滤波法生成粗糙断裂。研究结果表明，对于 0 至 0.3 毫米的裂缝孔径，主要的热传导机制是热传导，地下水流的贡献微乎其微。然而，当孔径从 0.3 毫米扩大到 2 毫米时，地下水流显著增强了热传导，超过 2 毫米后趋于稳定。在孔径为 0.2 毫米时，裂缝粗糙度的增加并不会提高热交换管的热回收性能，但在孔径为 4 毫米时，粗糙度与热传递之间出现了强烈的正相关。因此，狭窄的裂缝可视为光滑的，而较宽的裂缝则必须考虑粗糙度。裂缝流动与达西渗流之间的相互作用随着地下水水头的增加而增强，从而显著改善了换热管的汲取热量性能。当相对位置从 0.75 °C 过渡到 0 °C 时，换热管的出口水温上升了约 9 °C。

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引用次数: 0

Permeability characteristics and empirical prediction of cementitious soil rock mixtures based on numerical experiments of mesostructure 基于中观结构数值实验的水泥基土岩混合物的渗透性特征和经验预测

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-10 DOI: 10.1016/j.compgeo.2024.106813

Due to material composition and structure effects, the permeability characteristics of cementitious soil rock mixtures (CSRMs) significantly differ from homogeneous rock and soil mass, and the great discreteness in limited indoor or in-situ experimental data has always shown up. This study established the stochastic mesostructure models of CSRMs with a self-developed modeling technology. Their saturated and unsaturated seepage parameters were determined by laboratory tests. Then, saturated and unsaturated numerical seepage simulations of CSRMs were carried out. The influences of rock block content, occurrence, shape, and permeability difference in soil and rock mass on their permeability coefficient were investigated. The empirical permeability coefficient prediction formulas about influencing factors were discussed. The results showed that the seepage characteristics of CSRMs conformed to Darcy’s law. Their permeability coefficient decreased first and then increased with the rock block content, and they achieved the minimum value when it was about 40 %. Their permeability coefficient increased with the rock block inclination and decreased with the aspect ratio of rock blocks. When the difference of soil and rock mass in permeability coefficient exceeded 1 × 10³ in magnitude, their permeability coefficient should be mainly controlled by the side with the large permeability. Three empirical permeability prediction formulas for CSRMs were proposed. This study could provide theoretical and methodological references for the permeability cognition of CSRMs.

由于材料组成和结构的影响，水泥基土岩混合物（CSRMs）的渗透特性与均质岩土体存在显著差异，在有限的室内或原位实验数据中总是表现出很大的离散性。本研究利用自主研发的建模技术建立了 CSRM 的随机介观结构模型。通过实验室试验确定了其饱和及非饱和渗流参数。然后，对 CSRMs 的饱和及非饱和渗流进行了数值模拟。研究了岩块含量、出现、形状以及土体和岩块的渗透性差异对其渗透系数的影响。讨论了有关影响因素的经验渗透系数预测公式。结果表明，CSRM 的渗流特性符合达西定律。随着岩块含量的增加，其渗透系数先减小后增大，当岩块含量为 40% 左右时，其渗透系数达到最小值。其渗透系数随岩块倾斜度的增加而增大，随岩块长宽比的增加而减小。当土块和岩块的渗透系数之差超过 1 × 103 时，其渗透系数应主要由渗透系数大的一侧控制。提出了 CSRM 的三种经验渗透率预测公式。该研究可为 CSRM 的渗透认知提供理论和方法参考。

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引用次数: 0

RDT-FragNet: A DCN-Transformer network for intelligent rock fragment recognition and particle size distribution acquisition RDT-FragNet：用于智能岩石碎块识别和粒度分布采集的 DCN 变压器网络

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-10 DOI: 10.1016/j.compgeo.2024.106809

Accurately and promptly identifying rock fragments and particle size distribution after blasting is crucial for rock transportation and aggregate control in hydraulic and hydropower engineering. Manual screening and traditional edge detection methods suffer from subjectivity and inefficiency, resulting in considerable processing time. Images of rock fragments post-blasting, captured in open-air conditions, present challenges due to overlapping fragments, complicating intelligent recognition. To address this, an instance segmentation model, RDT-FragNet, is designed for rock fragment segmentation. RDT-FragNet is a hybrid model that integrates the Deformable Convolutional Network (DCN) and the Transformer Attention Mechanism (TAM). The DCN-Transformer structure adaptively preserves global and local features, enhancing the segmentation and recognition of rock fragment edges. Comparative analyses and rigorous ablation studies demonstrate RDT-FragNet’s competitive advantages. RDT-FragNet outperforms other advanced models in both quantitative metrics and visual results. The visualization results and the characteristic and maximum particle size of rock fragments closely match the actual situation. The robustness and applicability of the RDT-FragNet model are validated using images from two additional engineering projects. This research introduces an intelligent, efficient, and objective method for rock fragment analysis in open-air settings.

在水利水电工程中，准确及时地识别爆破后的岩石碎块和粒度分布对于岩石运输和集料控制至关重要。人工筛选和传统的边缘检测方法存在主观性和效率低下的问题，导致处理时间相当长。爆破后的岩石碎块图像是在露天条件下拍摄的，由于碎块相互重叠，给智能识别带来了挑战。为此，我们设计了一个用于岩石碎片分割的实例分割模型 RDT-FragNet。RDT-FragNet 是一种混合模型，集成了可变形卷积网络（DCN）和变压器注意机制（TAM）。DCN-Transformer 结构自适应地保留了全局和局部特征，增强了岩石碎片边缘的分割和识别能力。对比分析和严格的烧蚀研究证明了 RDT-FragNet 的竞争优势。RDT-FragNet 在定量指标和可视化结果方面都优于其他先进模型。可视化结果以及岩石碎块的特征和最大粒度与实际情况非常吻合。利用另外两个工程项目的图像验证了 RDT-FragNet 模型的稳健性和适用性。这项研究为露天环境下的岩石碎块分析引入了一种智能、高效和客观的方法。

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引用次数: 0

Mesoscopic representation of conventional concrete and rock-filled concrete: A novel FEM-SBFEM coupled approach 传统混凝土和岩石填充混凝土的介观表示：新型 FEM-SBFEM 耦合方法

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-10 DOI: 10.1016/j.compgeo.2024.106820

A thorough characterization of the mesostructure of concrete serves as a fundamental cornerstone for investigating its complex mechanical response at the mesoscale. A coupled FEM-SBFEM (Finite element method − scaled boundary finite element method) model is developed for mesoscopic modeling of conventional concrete (CC) and rock-filled concrete (RFC). This model incorporates a novel RAM (Random Aggregate Model) generation procedure based on Laguerre tessellation, allowing for the construction of coarse polyhedral aggregates with diverse grading schemes and adjustable aggregate volume fractions. Moreover, a framework has been developed for the automatic generation of prelaid rock skeletons, which accurately encapsulate the distinctive self-sustaining skeletal characteristics inherent to RFC. In a departure from conventional FEM, the SBFEM in this approach discretizes each coarse aggregate using a singular polyhedral element, resulting in a significant reduction in degrees of freedom. The proposed mesoscopic construction method is adopted for the prediction of elastic properties for both CC and RFC. Numerical samples of 48 CC specimens and 13 RFC specimens, with various aggregate volume fractions and rockfill ratios, are constructed using Monte Carlo simulations, and the results are compared with experimental and numerical data in literature. Statistical analyses are performed to investigate the impacts of aggregate volume fraction and anisotropic behavior on the elastic properties of CC and RFC. The results demonstrate that RFC exhibited an elastic modulus approximately 7.32 % higher than CC at the same coarse aggregate volume fractions. Furthermore, RFC exhibits a more substantial degree of anisotropy than CC. The proposed FEM-SBFEM coupled approach presents the capability to accurately predict the elastic behavior of concrete materials, and can be extended for a comprehensive investigation of the linear and nonlinear properties of actual RFC that comprises extremely coarse aggregates.

对混凝土中观结构的全面描述是研究其在中观尺度上复杂力学响应的基础。我们开发了一种 FEM-SBFEM（有限元法-比例边界有限元法）耦合模型，用于传统混凝土（CC）和岩石填充混凝土（RFC）的中观建模。该模型采用了基于拉盖尔网格的新颖 RAM（随机骨料模型）生成程序，允许构建具有不同级配方案和可调骨料体积分数的粗多面体骨料。此外，还开发了一个自动生成预铺岩石骨架的框架，该框架准确地概括了 RFC 固有的独特自持骨架特征。与传统的有限元法不同，该方法中的 SBFEM 使用奇异多面体元素对每个粗集料进行离散，从而显著降低了自由度。在预测 CC 和 RFC 的弹性特性时，采用了所提出的介观构造方法。采用蒙特卡洛模拟构建了 48 个 CC 试件和 13 个 RFC 试件的数值样本，试件具有不同的骨料体积分数和填石比，并将结果与文献中的实验和数值数据进行了比较。通过统计分析，研究了骨料体积分数和各向异性行为对 CC 和 RFC 弹性特性的影响。结果表明，在粗骨料体积分数相同的情况下，RFC 的弹性模量比 CC 高出约 7.32%。此外，RFC 比 CC 表现出更大程度的各向异性。所提出的 FEM-SBFEM 耦合方法能够准确预测混凝土材料的弹性行为，并可扩展用于全面研究由极粗骨料组成的实际 RFC 的线性和非线性特性。

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引用次数: 0

A novel hybrid PD-FEM-FVM approach for simulating hydraulic fracture propagation in saturated porous media 模拟饱和多孔介质中水力压裂传播的新型 PD-FEM-FVM 混合方法

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-10 DOI: 10.1016/j.compgeo.2024.106821

To enhance the computational efficiency of fluid–solid coupling in peridynamics (PD), a hybrid modeling approach based on the classical Biot theory is proposed for simulating hydraulic crack propagation in saturated porous media. The deformation and damage of solids are described by the coupling of the finite element method (FEM) and PD. Based on Darcy’s law, the finite volume method (FVM) is used to describe fluid seepage and calculate pore water pressure. The mutual transfer of fluid pressure and solid deformation is realized through the transition layer between the solid layer and the fluid layer. Firstly, the effectiveness of the proposed method is verified by a porous media seepage simulation example. Secondly, the ability and efficiency of this method to simulate crack propagation in saturated porous media are verified by several examples of hydraulic fracturing of rock with a single pre-existing crack. Finally, the synchronous hydraulic fracturing process of rock with double cracks is simulated. The ability of this method to simulate the simultaneous propagation of multiple fractures in the rock under fluid–solid coupling is further illustrated. The aforementioned studies demonstrate that the novel hybrid PD-FEM-FVM approach not only ensures computational accuracy and effectiveness but also significantly enhances computational efficiency.

为了提高周动力学（PD）中流固耦合的计算效率，我们提出了一种基于经典 Biot 理论的混合建模方法，用于模拟饱和多孔介质中的水力裂缝扩展。固体的变形和损伤是通过有限元法（FEM）和周流体力学（PD）的耦合来描述的。根据达西定律，采用有限体积法（FVM）描述流体渗流并计算孔隙水压力。流体压力和固体变形的相互传递是通过固体层和流体层之间的过渡层实现的。首先，通过多孔介质渗流模拟实例验证了所提方法的有效性。其次，通过几个具有单个预存裂缝的岩石水力压裂实例，验证了该方法模拟饱和多孔介质中裂缝扩展的能力和效率。最后，模拟了双裂缝岩石的同步水力压裂过程。进一步说明了该方法在流固耦合条件下模拟岩石中多条裂缝同时扩展的能力。上述研究表明，新型 PD-FEM-FVM 混合方法不仅能确保计算精度和有效性，还能显著提高计算效率。

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引用次数: 0

Multiscale data-driven modeling of transient deposition physics of dense granular flows 多尺度数据驱动的致密颗粒流瞬态沉积物理学建模

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-10 DOI: 10.1016/j.compgeo.2024.106825

Geophysical flows involving granular masses exhibit complex dynamics with transient mass and momentum changes due to deposition. Geophysical flows are typically simulated using depth-averaged (DA) models, which rely on empirical closures for deposition. However, these models typically overlook the detailed grain-scale physics involved in deposition, treating the flow as an equivalent fluid at the macro-scale. This study introduces a multiscale framework to integrate grain-scale deposition physics into macro-scale DA models without relying on empirical closures. The framework utilizes a surrogate model, trained on discrete element modeling (DEM) datasets, to capture changes in effective flow depth. This surrogate model is integrated with a DA model to create a multiscale approach, improving the deposition physics within an efficient computational framework. The effectiveness of the proposed multiscale framework is assessed by studying how a granular mass, initially in motion, settles when the slope angle is suddenly reduced to zero. Predictions from the multiscale model of effective flow depth (i.e., not including deposited material) and DA velocity are compared with DEM results. It is demonstrated that the proposed framework has potential to streamline upscaling simulations and facilitate field-scale hazard assessments in the future.

涉及粒状物质的地球物理流表现出复杂的动力学特征，由于沉积作用而产生瞬时质量和动量变化。地球物理流动通常使用深度平均（DA）模型进行模拟，这些模型依赖于沉积的经验闭合。然而，这些模型通常忽略了沉积过程中涉及的详细晶粒尺度物理现象，而将流动视为宏观尺度上的等效流体。本研究引入了一个多尺度框架，在不依赖经验闭合的情况下，将颗粒尺度沉积物理学整合到宏观尺度 DA 模型中。该框架利用在离散元建模（DEM）数据集上训练的代用模型来捕捉有效流深的变化。该代用模型与大尺度模型相结合，创建了一种多尺度方法，在一个高效的计算框架内改进了沉积物理学。通过研究最初处于运动状态的颗粒质量在坡度角突然减小为零时如何沉降，对所提出的多尺度框架的有效性进行了评估。多尺度模型对有效流深（即不包括沉积物）和DA速度的预测结果与DEM结果进行了比较。结果表明，所提出的框架具有简化升级模拟的潜力，并有助于未来进行实地规模的灾害评估。

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引用次数: 0

Comprehensive multivariate joint distribution model for marine soft soil based on the vine copula 基于藤状协约的海洋软土综合多变量联合分布模型

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-10 DOI: 10.1016/j.compgeo.2024.106814

In this study, we propose a multivariate joint distribution model for marine soft soil using D-vine copula function. The model is based on detailed investigation data from a tunnel constructed in marine soft soil. The variation patterns of the mechanical and physical parameters of quaternary marine–land interaction sedimentary soft soil layers were analysed. First, a comprehensive database of marine soft soils was established on the basis of detailed field investigation data. The variability and correlations among the physical and mechanical performance indices of the soft soil were then analysed. Subsequently, optimal marginal functions for nine soil parameters were proposed on the basis of the fitting characteristics of the physical and mechanical performance parameters of the soft soil. Finally, 15 copula functions were used to establish a multivariate joint distribution model of the D-vine copula function for marine soft soil, and the effectiveness of the model was verified. This model offers flexibility for constructing multivariate joint distributions tailored to various characteristics of the correlation structure by leveraging several bivariate correlation structures. It can provide an effective method for accurately delineating the features of the correlation structure among multivariate geotechnical parameters and establishing a probabilistic transformation model for marine soft soil parameters.

在本研究中，我们利用 D-vine copula 函数提出了海洋软土的多元联合分布模型。该模型基于在海洋软土中建造的隧道的详细调查数据。分析了第四纪海陆相互作用沉积软土层力学和物理参数的变化规律。首先，根据详细的实地调查数据建立了全面的海洋软土数据库。然后，分析了软土物理和力学性能指数之间的变异性和相关性。随后，根据软土物理和力学性能参数的拟合特征，提出了九个土壤参数的最佳边际函数。最后，利用 15 个协整函数建立了海洋软土 D-藤协整函数多变量联合分布模型，并验证了该模型的有效性。该模型通过利用多个二元相关结构，灵活构建了适合各种相关结构特征的多元联合分布。它为准确划分多元岩土参数之间的相关结构特征和建立海洋软土参数的概率变换模型提供了有效方法。

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引用次数: 0

Coupled vibratory roller and layered unsaturated subgrade model for intelligent compaction 用于智能压实的振动压路机和分层非饱和路基耦合模型

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-10 DOI: 10.1016/j.compgeo.2024.106827

To provide theoretical guidance for intelligent compaction, this study proposes an efficient analytical model that considers the coupled dynamic interaction between a vibratory roller and a layered subgrade. The vibratory roller is simulated using a lumped parameter model, while the subgrade is characterized as a layered unsaturated poroelastic medium. The governing equations are solved using the double Fourier transform to derive the steady-state solution of this fully coupled model. The correctness of the proposed model is verified by comparing it with published analytical results and field test results. Results indicate that the vertical acceleration response of the roller drum is sensitive to variations in subgrade modulus. However, when evaluating the modulus of the current filling layer, it is crucial to consider the effects of the underlying layer on the acceleration response of the roller drum, especially when the existing subgrade thickness is less than 2 m. The influence of excitation frequency on the sensitivity of vertical acceleration response is found to be significant. For subgrade quality assessment with existing subgrade thickness less than 2 m, a low-frequency excitation load is recommended to maximize sensitivity, while both low and high excitation frequencies can be employed for thicker existing subgrades.

为了给智能压实提供理论指导，本研究提出了一种高效的分析模型，该模型考虑了振动压路机与分层基层之间的耦合动态相互作用。振动压路机采用集合参数模型进行模拟，而基层则被描述为分层非饱和孔弹性介质。利用双傅立叶变换求解了控制方程，从而得出了这一完全耦合模型的稳态解。通过与已公布的分析结果和现场测试结果进行比较，验证了所提模型的正确性。结果表明，压路机滚筒的垂直加速度响应对基层模量的变化非常敏感。然而，在评估当前填充层的模量时，必须考虑下层对压路机滚筒加速度响应的影响，尤其是当现有基层厚度小于 2 米时。对于现有基层厚度小于 2 米的基层质量评估，建议采用低频激振载荷，以最大限度地提高灵敏度；而对于较厚的现有基层，可同时采用低频和高频激振载荷。

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引用次数: 0

Compaction quality assessment of road subgrades using explainable deep graph learning framework 利用可解释深度图学习框架评估路基压实质量

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-09 DOI: 10.1016/j.compgeo.2024.106795

Compaction-quality assessment based on machine learning is an attractive topic in road construction research. However, existing methods do not consider the structural information of data when predicting the compaction degree. Thus, an explainable deep graph learning framework is proposed for the intelligent compaction quality assessment of road subgrades. In this method, a multi-domain analysis is first used to extract different indicators from the vibration signals of a vibratory roller. Second, the indicators for the different sampling points are constructed as graph structure data. Finally, an alternating graph-regularized regression network (AGRN) is developed to learn features from the graph data and aggregate the features using a regressor to predict the compaction degree. Through experimental verification, the proposed method displays an improved generalization ability and a high prediction accuracy when compared with other methods. Moreover, Shapley additive explanations (SHAP) are introduced to measure the marginal contributions of indicators for predicting the compaction degree in compaction quality assessments.

基于机器学习的压实质量评估是道路建设研究中一个极具吸引力的课题。然而，现有方法在预测压实度时并未考虑数据的结构信息。因此，本文提出了一种可解释的深度图学习框架，用于智能评估路基压实质量。在该方法中，首先使用多域分析法从振动压路机的振动信号中提取不同的指标。其次，将不同采样点的指标构建为图结构数据。最后，开发交替图正则化回归网络（AGRN），从图数据中学习特征，并使用回归器汇总特征，预测压实度。通过实验验证，与其他方法相比，所提出的方法显示出更强的泛化能力和更高的预测精度。此外，在压实质量评估中，引入了夏普利加法解释（SHAP）来衡量预测压实度指标的边际贡献。

引用次数: 0

A unified soil reaction model for laterally loaded monopiles in soft and stiff clays 软粘土和硬粘土中横向加载单桩的统一土壤反力模型

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-09 DOI: 10.1016/j.compgeo.2024.106819

To develop a unified soil reaction model suitable for laterally loaded monopiles in soft and stiff clays, this paper employs an experimentally validated numerical method to analyze the influence of diameter, embedded length (L), and clay types (soft or stiff) on the soil reaction model, proposing a unified model based on hyperbolic soil reaction curve. This model fully considers the contributions of distributed lateral load, base moment, base shear force, and distributed moment to the lateral resistance. The results of the analysis indicate that the ultimate normalized lateral soil resistance (

{\bar{p}}_{u}

) of soft and stiff clays in the wedge flow zone increases with depth, reaching a peak in the full flow zone with the peak points located around 0.5 L. The maximum of

{\bar{p}}_{u}

between soft and stiff clays is positively correlated with the ratio of effective vertical stress to undrained shear strength (

σ_{v}^{'} / s_{u}

) at the current depth. The ultimate base shear force and base moment for monopiles in soft and stiff clays can also be represented by

σ_{v}^{'} / s_{u}

at the base. Through rigorous validation with centrifuge and field tests, the unified soil reaction model proposed in this paper can accurately predict the response of monopiles in soft and stiff clays.

为了建立适用于软粘土和硬粘土中横向加载单桩的统一土体反力模型，本文采用了一种经过实验验证的数值方法，分析了直径、嵌入长度（L）和粘土类型（软或硬）对土体反力模型的影响，提出了一种基于双曲土体反力曲线的统一模型。该模型充分考虑了分布侧向荷载、基底弯矩、基底剪力和分布弯矩对侧向阻力的贡献。分析结果表明，楔流区软粘土和硬粘土的极限归一化侧向阻力（p¯u）随深度增加而增加，在全流区达到峰值，峰值点位于 0.5 L 左右。软粘土和硬粘土中单桩的极限基底剪力和基底弯矩也可以用基底的 σv′/su 表示。通过离心机和现场试验的严格验证，本文提出的统一土体反应模型可以准确预测单桩在软粘土和硬粘土中的反应。

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引用次数: 0