Geomechanics for Energy and the Environment最新文献_第6页

Influence of matric suction on the behavior of energy pile groups under geometrically asymmetrical thermal cycling 几何不对称热循环条件下基质吸力对能量桩群性能的影响

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-10-16 DOI: 10.1016/j.gete.2025.100760

Sina Afzalsoltani , Fardin Jafarzadeh , Salar Lakimahalleh

The behavior of energy pile groups under geometrically asymmetrical thermal loading in unsaturated soils presents a critical design challenge. The combined effects of group interaction, loading asymmetry, and soil suction on system performance are not fully understood. This study investigates these phenomena through 1 g physical model tests on 2 × 2 pile groups and isolated piles, with the results synthesized into a novel framework using contour maps to visualize the coupled system responses. Under mechanical load, group interaction effects were significant; an individual pile in the unsaturated group settled 26 % more than an isolated pile. Matric suction proved beneficial, reducing this settlement from 2.8 % of the pile diameter in the dry group to 2.1 % in the unsaturated group. During thermal cycling, asymmetrical loading induced significant cap tilting, peaking at 0.47 % and substantially exceeding the 0.2 % Eurocode serviceability limit. Load transfer mechanisms were also distinct between isolated and grouped piles. In unsaturated group tests, the mobilized end bearing of an energy pile increased by a factor of up to 2.5, which was substantially more than the 1.6-fold increase seen in isolated pile tests. Consequently, the soil pressure beneath the group pile tips was significantly greater, with the pressure under the energy pile in the G1P group being 1.87 times that recorded for the single pile. The study quantitatively demonstrates that while matric suction improves resistance, group interactions reduce per-pile efficiency, and asymmetrical thermal loading is the dominant factor controlling cap rotation, posing a significant serviceability risk.

非饱和土中几何不对称热荷载作用下能量桩群的性能是一个重要的设计挑战。群体相互作用、荷载不对称和土壤吸力对系统性能的综合影响尚未完全了解。本研究通过对2个 × 2个桩群和孤立桩进行1 g物理模型试验来研究这些现象，并利用等高线图将结果综合成一个新的框架来可视化耦合系统的响应。在机械载荷作用下，群体相互作用效应显著；非饱和群中单个桩的沉降比孤立桩多26% %。事实证明，基质吸力是有益的，将沉降从干桩组的2.8 %降低到非饱和桩组的2.1 %。在热循环过程中，不对称载荷引起显著的帽倾斜，峰值为0.47 %，大大超过0.2 %欧洲规范的使用极限。孤立桩和群桩之间的荷载传递机制也不同。在非饱和群试验中，能量桩的动端承载力增加了2.5倍，大大超过了隔离桩试验的1.6倍。因此，群桩桩尖下土压力明显较大，其中G1P组能量桩下土压力是单桩的1.87倍。该研究定量地表明，虽然基质吸力提高了阻力，但群相互作用降低了单桩效率，不对称热载荷是控制承台旋转的主要因素，带来了显著的使用风险。

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引用次数: 0

Experimental study of sugar-induced sand cementation in dry conditions 干燥条件下糖诱导砂胶结试验研究

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-11-07 DOI: 10.1016/j.gete.2025.100765

Gianmario Sorrentino , Andrea Franza

This paper presents an experimental study of sugar as a low-viscosity cementing agent for sand in dry laboratory conditions. Sand was mixed with aqueous sugar solutions of varying concentrations (15%–40% by mass) and oven-cured at different temperatures. Unconfined compressive strength (UCS) tests showed that strength increased with sugar concentration, with UCS values reaching up to 6 MPa —comparable to or exceeding those achieved with conventional bio-cementation methods. Optimal curing occurred at 105 °C, balancing rapid hardening and peak strength, while excessive heating at 170 °C reduced strength due to sugar caramelisation. Nevertheless, all conditions yielded mean UCS values above 1 MPa, demonstrating the method’s reliability. Scanning electron microscopy (SEM) was used to observe the interaction between sugar and sand particles, revealing a substantial sugar coating bonding the grains. These findings reveal some of the fundamental mechanisms of sugar-induced cementation. Finally, research pathways and current shortcomings for field applications are discussed.

本文介绍了在干燥实验室条件下，糖作为低粘度砂胶凝剂的实验研究。将沙子与不同浓度的糖水溶液混合（质量比例为15%-40%），并在不同温度下进行烤炉固化。无侧限抗压强度（UCS）测试表明，强度随糖浓度的增加而增加，UCS值可达6 MPa，与常规生物胶结方法的结果相当或超过。最佳固化温度为105°C，可以平衡快速硬化和峰值强度，而在170°C下过度加热会因糖焦糖化而降低强度。尽管如此，所有条件下的平均UCS值都在1 MPa以上，证明了该方法的可靠性。利用扫描电子显微镜（SEM）观察了砂粒与砂粒之间的相互作用，发现砂粒之间有一层糖包覆层。这些发现揭示了糖诱导的胶结的一些基本机制。最后，讨论了现场应用的研究途径和目前存在的不足。

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引用次数: 0

An effective poroelastic model for fractured porous media 裂缝性多孔介质的有效孔隙弹性模型

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-12-04 DOI: 10.1016/j.gete.2025.100772

Renato E.B. Poli, D. Nicolas Espinoza, Kamy Sepehrnoori

Fractures are present in many types of porous media, including rock formations. While the impact of the fractures on fluid flow processes has been extensively investigated, methods for rigorous poromechanical upscaling including fluid mass and momentum conservation into effective models are still limited. Considering the limitations of experimental assessment of large rock masses, this work proposes the use of a numerical approach to understand and calculate the effective poromechanical quasi-static response of a fractured porous medium. First, we detail the design and validation of a high-performance poroelastic simulator with conforming fractures. Then a series of sensitivity analyses investigates the effective response of a linear poroelastic medium with a fracture network. An unstructured mesh generator coupled to a Monte Carlo simulation engine helps explore the intrinsic uncertainties of the system, both in the continuum and fracture domains. The findings indicate that fracture networks are most impactful in scenarios of low effective stress, which is typically the case of shallow rock formations, high pore pressure, or fluid injection at low temperatures. The impact on the effective drained bulk modulus

\overset{̅}{K}

, the drained Poisson ratio

\overset{̅}{ν}

and the drained Biot coefficient

\overset{̅}{α}

is strongly correlated to the fracture density, while the effective undrained Skempton

\overset{̅}{B}

and Biot Modulus

\overset{̅}{M}

are more sensitive to fluid compressibility as the fluid storage added due to fracture volume and deformation becomes dominant. Finally, the uncertainty assessment provides recommendations for geomechanical modelers attempting to capture effective poroelastic parameterization at the field scale. For example, contrary to usual practice, it is correct to assume a large-scale effective Biot coefficient near unity for highly fractured stiff rocks such as dolomite or granite.

裂缝存在于许多类型的多孔介质中，包括岩层。虽然裂缝对流体流动过程的影响已经得到了广泛的研究，但将流体质量和动量守恒纳入有效模型的严格孔隙力学升级方法仍然有限。考虑到大型岩体实验评估的局限性，本工作提出使用数值方法来理解和计算裂隙多孔介质的有效孔隙力学准静态响应。首先，我们详细介绍了具有一致性裂缝的高性能孔隙弹性模拟器的设计和验证。在此基础上，通过一系列的灵敏度分析，研究了含裂缝网络的线性孔隙弹性介质的有效响应。与蒙特卡罗模拟引擎相结合的非结构化网格生成器有助于探索系统在连续体和断裂域中的内在不确定性。研究结果表明，裂缝网络在有效应力较低的情况下影响最大，通常是在浅岩层、高孔隙压力或低温下注入流体的情况下。有效泄油体积模量K′′、泄油泊松比ν′′和泄油Biot系数α′′的影响与裂缝密度密切相关，而有效泄油Skempton B′′和Biot模量M′′对流体可压缩性更为敏感，裂缝体积和变形增加的储液量占主导地位。最后，不确定性评估为试图在现场尺度上捕获有效孔隙弹性参数化的地质力学建模者提供了建议。例如，与通常做法相反，对于白云岩或花岗岩等高度断裂的坚硬岩石，假设大尺度有效比奥系数接近统一是正确的。

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引用次数: 0

Predicting subsurface thermal conductivity from wellbore temperatures 根据井筒温度预测地下导热系数

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-09-18 DOI: 10.1016/j.gete.2025.100745

Josiane Jello , Patrick Harsono , Tugce Baser

This study focuses on the prediction of subsurface thermal conductivity using in-situ wellbore temperature profiles by solving an inverse one-dimensional heat equation. Existing methods to measure or estimate thermal conductivity either require core samples, empirical correlations, or are only applicable to shallow depths. To demonstrate how thermal conductivity can be accurately predicted from borehole temperature data collected using a fiber-optic distributed temperature sensing (DTS) system, a field-scale heat injection experiment was performed in an open oil well located near Fairfield, Illinois. The heat equation was solved numerically based on the finite difference method and it was used to predict wellbore temperatures. An optimization technique was introduced into the finite difference model to predict the thermal diffusivity, which was then used to predict the thermal conductivity as these two properties are proportional. A thermal conductivity profile which is consistent with the anticipated thermal properties of the geological strata is obtained and the results from the analyses showed that the thermal conductivity values varied between 0.42 and 5.36 W/m.K. The highest mean square error (MSE) recorded was relatively small with a value of less than 0.005℃. The model presented in this study can widely be used with DTS measurements to predict the subsurface thermal conductivity. This model presents a useful tool to better characterize thermal properties for the design of efficient geothermal systems when the evolution of wellbore temperatures is known.

本研究的重点是通过求解一维逆热方程，利用原位井筒温度剖面预测地下导热系数。现有的测量或估计热导率的方法要么需要岩心样品，要么需要经验相关性，要么只适用于较浅的深度。为了演示如何利用光纤分布式温度传感（DTS）系统收集的井温数据准确预测热导率，在伊利诺伊州费尔菲尔德附近的一口露天油井中进行了现场规模的热注入实验。基于有限差分法对热方程进行数值求解，并将其应用于井筒温度预测。在有限差分模型中引入最优化技术来预测热扩散系数，并将其用于预测导热系数，因为两者是成比例的。得到了与预期地层热物性相符的热导率剖面，分析结果表明，热导率值在0.42 ~ 5.36 W/m.K之间。记录的最高均方误差（MSE）较小，小于0.005℃。本研究提出的模型可以广泛地与DTS测量相结合来预测地下热导率。当井筒温度的变化已知时，该模型提供了一个有用的工具，可以更好地表征热特性，从而设计高效的地热系统。

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引用次数: 0

Permeability evolution and predictive modeling in grout-reinforced fractured rock masses: An intelligent computational approach 注浆加固裂隙岩体渗透率演化与预测建模：一种智能计算方法

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-10-02 DOI: 10.1016/j.gete.2025.100754

Yachao Guo , Junmeng Li , Yanli Huang , Yingshun Li , Jiachen Liu , Guiyuan Wang , Zuo Sun

The permeability evolution characteristics of grout-reinforced fractured rock masses significantly influence the seepage stability control in underground engineering. In this study, fractured sandstone specimens under various confining pressures (0–10 MPa) were prepared using a high-pressure triaxial testing system. Reinforcement was performed using coal gangue-fly ash-based grout, and the permeability variations under effective stresses (1–9 MPa) were systematically measured before and after grouting. A permeability prediction model for grouted rock masses was established by employing swarm intelligence algorithms (Particle Swarm Optimization (PSO), Genetic Algorithm (GA), and Grey Wolf Optimizer (GWO)), and an interactive computational platform was developed. The results show that post-grouting permeability decreased by 54.83–99.75 % compared to pre-grouting values, exhibiting a power-law decline with increasing effective stress. Using six key factors—including fracture stress state, initial permeability, and grouting parameters—an 80-sample training dataset was constructed. A backpropagation (BP) neural network (6-7-1 topology) optimized by the GWO achieved high-precision permeability prediction (R² = 0.997, MAE = 0.051). Finally, a Python-based intelligent interactive computing system was developed, integrating parameter control, model computation, and result visualization. This provides theoretical support and technical tools for engineering grout design.

注浆加固裂隙岩体的渗透演化特征对地下工程渗流稳定控制具有重要影响。本研究采用高压三轴试验系统制备了不同围压（0-10 MPa）条件下的裂隙砂岩试件。采用煤矸石-粉煤灰基注浆进行加固，系统测量了注浆前后有效应力（1 ~ 9 MPa）下的渗透率变化。采用粒子群算法（PSO）、遗传算法（GA）和灰狼优化算法（GWO）建立了注浆岩体渗透率预测模型，并开发了交互式计算平台。结果表明：灌浆后渗透率较灌浆前降低54.83 ~ 99.75 %，随有效应力的增加呈幂律递减；利用断裂应力状态、初始渗透率、注浆参数等6个关键因素，构建了80个样本的训练数据集。利用GWO优化的BP神经网络（6-7-1拓扑）实现了高精度的渗透率预测（R2 = 0.997, MAE = 0.051）。最后，开发了一个集参数控制、模型计算和结果可视化于一体的基于python的智能交互计算系统。这为工程注浆设计提供了理论支持和技术工具。

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引用次数: 0

Energy and entropy balance laws for porous media saturated by one or two non-miscible pore fluids at different temperatures 不同温度下一种或两种非混溶孔隙流体饱和多孔介质的能量和熵平衡规律

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-08-29 DOI: 10.1016/j.gete.2025.100731

A. Gajo

The energy and entropy balance equations of porous media saturated by one or more non-miscible fluids have been investigated by many Authors leading to expressions which are based on different thermodynamic potentials and include various simplifying assumptions. Thus the various approaches often appear to be unrelated with respect to each other. In this work, two thermodynamic potentials recently proposed in the literature for porous media saturated by one or two non-miscible and compressible pore fluids are exploited for reconsidering different and perfectly equivalent expressions of the energy balance equations given in terms of internal energies, entropies and enthalpies, without simplifying assumptions. In particular, the entropy fluxes and the dissipation functions are presented for a simple case of irreversible response of the solid skeleton, involving neither irreversibility of the solid grain response, nor elastoplastic coupling nor frozen inelastic energy. Some comparisons with the formulations proposed in the literature are discussed.

许多作者研究了被一种或多种非混相流体饱和的多孔介质的能量和熵平衡方程，得出了基于不同热力学势和包含各种简化假设的表达式。因此，不同的方法往往显得彼此无关。在这项工作中，利用最近在文献中提出的两种热力学势，对由一种或两种非混溶和可压缩孔隙流体饱和的多孔介质进行重新考虑，以内能、熵和焓给出的能量平衡方程的不同和完全等价的表达式，而不简化假设。特别地，给出了固体骨架不可逆响应的简单情况下的熵通量和耗散函数，既不涉及固体颗粒响应的不可逆性，也不涉及弹塑性耦合和冻结的非弹性能量。并与文献中提出的公式进行了比较。

引用次数: 0

Strata control methods and optimization design for mining earthquake prevention and environmental protection 矿山防震环保岩层控制方法及优化设计

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-11-23 DOI: 10.1016/j.gete.2025.100774

Tiening Wang , Guangli Guo , Huaizhan Li , Hejian Yin , Hui Zheng , Fanzhen Meng , Liangui Zhang

High position super-thick overburden is a common geological structure in coal-bearing strata, and its fracture movement is extremely likely to trigger serious dynamic disasters. Large-scale coal mining is prone to cause the rupture of high position super-thick overburden, accompanied by a huge release of energy. Meanwhile, the disorderly accumulation of associated gangue has also led to severe ecological degradation. To address these challenges, this paper proposes a strata control method considering mine earthquake prevention and gangue treatment (SCMEG). Based on this, the stability evaluation model of high position super-thick overburden and the stability evaluation model of composite support pillar have been established. Then combined with gray wolf algorithm, the optimization design process driven by gangue disposal efficiency is put forward. The research achievement has been applied to Ordos mine, yielding optimal design parameters: caving mining width of 340 m, grouting filling width of 240 m. The comparative analysis results indicate that the optimized plan of SCMEG demonstrates significant advantages: it effectively prevents large-scale energy accumulation in the high position super-thick overburden, ensures the overall integrity of the overburden, and maintains the long-term stability of the composite support pillar. Simultaneously, the amount of gangue disposal matches the mining output, enabling efficient and large-scale gangue disposal in the mining area. The research provides theoretical support for the coordinated development of environmental protection and safe production in ecologically fragile mining areas.

高位超厚覆岩是含煤地层中常见的地质构造，其断裂运动极有可能引发严重的动力灾害。大规模采煤容易造成高位超厚覆岩破裂，并伴随巨大的能量释放。同时伴生脉石的无序堆积也导致了严重的生态退化。针对这些挑战，本文提出了一种考虑矿山防震与矸石处理的地层控制方法。在此基础上，建立了高位超厚覆盖层稳定性评价模型和复合支护矿柱稳定性评价模型。然后结合灰狼算法，提出了以矸石处理效率为驱动的优化设计过程。将研究成果应用于鄂尔多斯矿，得出了最优设计参数：崩落开采宽度340 m，注浆充填宽度240 m。对比分析结果表明，SCMEG优化方案具有显著优势，有效防止了高位超厚覆岩的大规模能量积聚，保证了覆岩的整体完整性，保持了复合支护柱的长期稳定性。同时，矸石处置量与开采产量相匹配，实现了矿区矸石的高效大规模处置。研究结果为生态脆弱矿区环境保护与安全生产协调发展提供了理论支持。

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引用次数: 0

Shape effect of shear box in large-scale direct shear test for soil-rock mixture 土石混合体大尺度直剪试验中剪切箱形状效应研究

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-09-25 DOI: 10.1016/j.gete.2025.100750

Yiliang Tu , Quanlin Huang , Qianglong Yao , Zhong Fang , Xinrong Liu , Hejun Chai

The large-scale direct shear test is one of the simplest and most efficient methods for testing the shear strength parameters of soil-rock mixtures (S-RM), with shear boxes available in various shapes such as circular and rectangular. However, it remains unclear whether the shear box shape affects the accuracy of the results from large-scale direct shear tests. Therefore, this study uses a three-dimensional (3D) discrete element method to construct a numerical model for large-scale direct shear tests on S-RM, accounting for realistic rock block shapes. Subsequently, the reliability of this numerical model was validated by comparing it with results from large-scale direct shear tests laboratory. Next, the direct shear test results of the same S-RM were compared between circular and square shear boxes. The results indicate that the test results in the square shear box are more accurate. In the circular shear box, the test results approximate those in the square shear box, but their deformation is not a strict plane strain. Finally, the influence of the length-width ratio (L/W) of the shear box on results of large-scale direct shear tests on S-RM is discussed. Results show that as the L/W decreases, the interlocking effect between rock blocks strengthens, the number of force chains increases, and the shear band thickness decreases; the stress-strain curve transitions from strain-softening to strain-hardening; both cohesion and internal friction angle exhibit two distinct trends within the range before and after the L/W reaches 1:1. Thus, in large-scale direct shear tests of S-RM, square shear boxes with a L/W of 1:1 are preferred, followed by rectangular shear boxes with a L/W greater than 1:1, while shear boxes with a L/W less than 1:1 should be avoided.

大型直剪试验是测试土石混合体抗剪强度参数最简单、最有效的方法之一，剪切箱有圆形和矩形等多种形状。然而，剪切箱的形状是否会影响大型直剪试验结果的准确性尚不清楚。因此，本研究采用三维（3D）离散元方法，在考虑真实岩块形状的情况下，构建S-RM大尺度直剪试验数值模型。通过与室内大型直剪试验结果的对比，验证了该数值模型的可靠性。接下来，比较了圆形和方形剪切箱对同一S-RM的直剪试验结果。结果表明，方形剪切箱的试验结果更为准确。在圆形剪切箱中，试验结果与方形剪切箱中的试验结果接近，但它们的变形不是严格的平面应变。最后，讨论了剪切箱长宽比（L/W）对S-RM大型直剪试验结果的影响。结果表明：随着L/W的减小，岩块间的联锁效应增强，力链数增加，剪切带厚度减小；应力-应变曲线由应变软化过渡到应变硬化；黏聚力和内摩擦角在L/W达到1:1前后表现出明显的变化趋势。因此，在S-RM大型直剪试验中，首选L/W为1:1的方形剪切箱，其次是L/W大于1:1的矩形剪切箱，而L/W小于1:1的剪切箱应避免使用。

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引用次数: 0

A machine learning-based thermal-mechanical parameter inversion of energy pile considering thermo-mechanical behaviors 考虑热力学行为的基于机器学习的能量桩热力学参数反演

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-09-28 DOI: 10.1016/j.gete.2025.100752

Chaoran Wang, Jiaxin Liu, Gia Trung Luu, Chanjuan Han

The thermal-mechanical properties of rock-soil are indispensable for the geotechnical investigation of energy piles according to design codes. The thermal parameters of the stratum and pile are commonly determined through thermal response tests (TRT), and the mechanical parameters are obtained via sampling or in-situ testing, with some parameters also assigned based on engineering experience. However, on the one hand, TRT and in-situ testing are costly and labor-intensive processes that last nearly one week. On the other hand, the accuracy of personal experience on parameter determination is not guaranteed. Parameter inversion adjusts numerically modelled values (originally from tests/experience) to compensate for sampling effects, stratigraphic variations, and human biases that create simulation errors. The machine learning-based surrogate model, experiencing a surge in popularity in recent years, is a promising solution for inversion acceleration. By training on precomputed numerical simulation results, the surrogate model emulates the system’s behavior at significantly faster speeds, simultaneously reducing computational time and financial costs compared to traditional numerical modelling. This study proposes a novel method for parameter inversion with machine-learning-based surrogate models. A numerical model is first established by replicating a reduced-scale physical test capturing the thermal-mechanical behaviors of the energy pile. The Latin hypercube sampling is subsequently utilized to generate sufficient data for XGBoost model development, where the sensitivity analysis is subsequently carried out for parameter screening. The parameter inversion is then implemented with non-dominated sorting genetic algorithms. The effectiveness of the method is validated using 4 real-case test conditions. The results demonstrate that the surrogate model attains high accuracy with an R² of temperature and axial forces above 0.97 and 0.9, respectively. Lastly, the results of parameter inversion indicate a promising and optimistic prospect for the proposed inversion method, which can reveal the comprehensive parameters of the material to a certain extent. This study presents an efficient method for parameter inversion of energy piles while providing a perspective of fast determination of rock-soil thermal properties.

根据设计规范进行能源桩岩土工程勘察时，岩土热力学特性是必不可少的。地层和桩的热参数一般通过热响应试验（TRT）确定，力学参数一般通过抽样或现场测试获得，部分参数也根据工程经验确定。然而，一方面，TRT和原位测试是一个耗时近一周的昂贵和劳动密集型过程。另一方面，不能保证个人经验对参数确定的准确性。参数反演调整数值模拟值（最初来自测试/经验），以补偿采样效应、地层变化和造成模拟误差的人为偏差。基于机器学习的代理模型近年来越来越受欢迎，是一种很有前途的反演加速解决方案。通过对预先计算的数值模拟结果进行训练，代理模型可以以更快的速度模拟系统的行为，同时与传统的数值模拟相比，减少了计算时间和财务成本。本研究提出了一种基于机器学习的代理模型参数反演的新方法。首先通过模拟能量桩的小尺度物理试验，建立了能量桩的数值模型。随后利用拉丁超立方体采样为XGBoost模型开发生成足够的数据，随后进行敏感性分析以进行参数筛选。然后用非支配排序遗传算法实现参数反演。通过4个实际测试条件验证了该方法的有效性。结果表明，该模型具有较高的拟合精度，温度和轴向力的R2分别在0.97和0.9以上。最后，参数反演结果表明，所提出的反演方法具有良好的应用前景，能在一定程度上揭示材料的综合参数。该研究为能量桩参数反演提供了一种有效的方法，同时为快速确定岩土热特性提供了前景。

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引用次数: 0

Incipient motion of sands in the pipe and numerical modelling of the pipe depth 砂在管道中的初始运动及管道深度的数值模拟

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 Epub Date: 2025-11-13 DOI: 10.1016/j.gete.2025.100768

Yingping Xiao , Hong Cao , Hong Pan , Guanyong Luo , Bo Li , Dongfeng Zhu

Backward erosion piping is an internal erosion process that creates shallow pipes at the interface between an impermeable cover layer and a sandy foundation. Shallow pipes develop intermittently towards the riverside. Seepage and pipe flow are the main drivers of pipe erosion. Accurately simulating this coupled system is crucial for revealing the underlying erosion mechanisms, and the pipe depth is a significant parameter in these simulations. The pipe depth is determined by applying the incipient motion condition of bed particles, a method which relies on the pipe being in a limit-state equilibrium. This condition, along with the depth-averaged critical velocity, is derived from a force balance analysis of a single particle at the pipe's bottom under upward seepage. Accordingly, a coupled approach simulating erosion in the pipe, groundwater flow, and pipe flow is proposed. Pipe deepening coupled with groundwater flow and pipe flow are simulated for some available experiments to illustrate this simulation approach.

反向侵蚀管道是一种内部侵蚀过程，在不透水覆盖层和砂质基础之间的界面上形成浅管道。浅管道断断续续地向河边延伸。渗流和管道流动是管道侵蚀的主要驱动因素。准确模拟这种耦合系统对于揭示潜在的侵蚀机制至关重要，而管道深度是这些模拟中的一个重要参数。利用床层颗粒的初始运动条件来确定管道深度，这种方法依赖于管道处于极限状态平衡。这一条件以及深度平均临界速度是通过对管道底部单个颗粒在向上渗流条件下的力平衡分析得出的。据此，提出了一种模拟管道侵蚀、地下水流动和管道流动的耦合方法。通过一些现有的实验，模拟了地下水流和管道流耦合下的管道深化。

引用次数: 0