Soils and Foundations最新文献_第5页

Upcycling rice husk biowaste to improve cement-based peat soil stabilization 稻壳生物废弃物升级利用改善水泥基泥炭土稳定性

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-12-01 Epub Date: 2025-09-18 DOI: 10.1016/j.sandf.2025.101685

Zhiliang Wang , Jiangpeng Cai , Miao Li , Linfang Shen

Traditional stabilizers, such as kaolin and sodium bentonite, introduce complications when applied to cement-based peat soil stabilization. This study explores biowaste stabilizers – rice husk ash (RHA) as a pozzolan material and rice husk fiber (RHF) as reinforcing – as a sustainable and practical alternative. A three-stage experimental strategy was designed to identify the optimal stabilization method. Stage 1 determined the ideal RHA particle size and content without RHF. Stage 2 incorporated RHF to assess its best pretreatment method and optimal dosage; Stage 3 investigated the stabilization mechanisms. A series of physical and mechanical experiments confirmed that RHA and RHF improved cement-based peat soil stabilization. RHA played a primary role as a pozzolanic material, while RHF is secondary as reinforcement. Unconfined compressive strength (UCS) increased by 146.6 % with RHA alone and by 202.1 % with both RHA and RHF compared to cement only. This is achieved by using fine RHA particles and Ca(OH)₂-treated RHF. The content for both RHA and RHF is critical, especially noting that the optimal content of RHA varies as the cement content varies. Microscopic analysis confirmed that RHA enhanced pozzolanic reaction, producing more cementitious products (C-S-H) that filled pores and bonded soil particles. Additionally, a significant quantity of cementitious products formed on the coarse surface of pre-treated RHF, reinforcing soil-fiber bonding. Stabilizing 1 m³ of peat soil by upcycling biowaste reduces carbon emissions by 61.9 % and costs by 25.8 % compared to using cement only. This study demonstrates that upcycling biowaste provides an effective, sustainable, economical, and easy-to-implement solution for improving cement-based peat soil stabilization.

传统的稳定剂，如高岭土和钠基膨润土，在应用于水泥基泥炭土稳定时引入了复杂性。本研究探索了生物废物稳定剂——稻壳灰（RHA）作为火山灰材料和稻壳纤维（RHF）作为增强剂——作为一种可持续和实用的替代品。设计了一个三阶段的实验策略来确定最优的稳定方法。第1阶段确定了理想的RHA粒度和含量，没有RHF。第二阶段纳入RHF，评价其最佳预处理方法和最佳剂量；第三阶段研究了稳定机制。一系列物理力学实验证实，RHA和RHF改善了水泥基泥炭土的稳定性。RHA作为火山灰材料起主要作用，而RHF作为补强剂起次要作用。无侧限抗压强度（UCS）与水泥相比，单独使用RHA可提高146.6%，同时使用RHA和RHF可提高202.1%。这是通过使用精细的RHA颗粒和Ca(OH)2处理的RHF来实现的。RHA和RHF的含量都是至关重要的，特别是RHA的最佳含量随着水泥含量的变化而变化。微观分析证实，RHA增强了火山灰反应，产生了更多的胶凝产物（C-S-H），这些胶凝产物填充了孔隙并粘合了土壤颗粒。此外，预处理后的RHF粗糙表面上形成了大量胶凝产物，加强了土壤-纤维的结合。与仅使用水泥相比，通过升级利用生物垃圾稳定1立方米泥炭土可减少61.9%的碳排放和25.8%的成本。该研究表明，生物垃圾的升级利用为改善水泥基泥炭土的稳定性提供了一种有效、可持续、经济且易于实施的解决方案。

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引用次数: 0

Bioremediation for seleno-oxyanions in tunnel-excavated muck using selenate-reducing bacterium Stutzerimonas stutzeri NT-I 利用硒还原菌Stutzerimonas stutzeri NT-I对隧道开挖淤泥中硒氧阴离子进行生物修复

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-08-12 DOI: 10.1016/j.sandf.2025.101659

Osamu Otsuka , Mitsuo Yamashita

Selenium is a rare metal found mainly in volcanic sediments; it is naturally distributed in Japan owing to its sulfide deposits. Selenium exists in soil as highly toxic and soluble seleno-oxyanions, namely, selenate and selenite. The Japanese government has established standards for soluble selenium concentrations in soil, achieved by water shielding or the addition of insolubilization agents. If the selenium (and/or other heavy metals) in tunnel-excavated muck exceeds the environmental standards, it should be treated similarly to contaminated soil. However, conventional treatments leave selenium residues in tunnel-excavated muck, preventing their reuse due to the risk of selenium re-elution. This study attempted to insolubilize soluble seleno-oxyanions in tunnel-excavated muck by adding the bacterium Stutzerimonas stutzeri NT-I, which reduces selenate to insoluble elemental selenium and then to volatile dimethyl diselenide. Selenate reduction tests were conducted by adding heavy metals, including As(III), As(V), Cd(II), Pb(II), and Fe(III), to examine the selenate reduction ability and growth of S. stutzeri NT-I in the presence of their ions. The results showed that the S. stutzeri NT-I reduced the selenate by 50 mg/L concentrations for all the tested contaminants. In naturally contaminated tunnel-excavated muck, heavy metal elements, nitrate, and nitrite contents were detected at levels of <50 mg/L, suggesting that they do not adversely affect the selenate reduction by S. stutzeri NT-I. The results indicate that selenium insolubilization using S. stutzeri NT-I can be applied to a wide range of tunnel-excavated muck.

硒是一种稀有金属，主要存在于火山沉积物中；由于其硫化物矿床，它在日本自然分布。硒在土壤中以高毒性和可溶性的硒氧离子存在，即硒酸盐和亚硒酸盐。日本政府已经建立了土壤中可溶性硒浓度的标准，通过水屏蔽或添加不溶剂来实现。如果隧道开挖淤泥中的硒（和/或其他重金属）超过环境标准，则应将其与受污染的土壤类似处理。然而，传统的处理方法将硒残留在隧道开挖的淤泥中，由于硒的再洗脱风险，使其无法再利用。本研究试图通过添加Stutzerimonas stutzeri NT-I细菌，使隧道开挖淤泥中的可溶性硒氧阴离子失溶，将硒酸盐还原为不溶性元素硒，然后转化为挥发性二甲基二硒化物。通过添加As（III）、As(V)、Cd（II）、Pb（II）和Fe（III）等重金属进行硒酸盐还原试验，考察S. stutzeri NT-I在其离子存在下的硒酸盐还原能力和生长情况。结果表明，S. stutzeri NT-I对所有被测污染物的硒酸盐浓度降低了50 mg/L。在自然污染的隧道开挖淤泥中，重金属元素、硝酸盐和亚硝酸盐含量在50 mg/L的水平下被检测到，这表明它们不会对S. stutzeri NT-I还原硒酸盐产生不利影响。结果表明，S. stutzeri NT-I对硒的不溶化作用可广泛应用于隧道开挖的淤泥中。

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引用次数: 0

Seismic bearing capacity of strip footing above cavities in rock masses 岩体空腔上方条形基础抗震承载力研究

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-08-26 DOI: 10.1016/j.sandf.2025.101681

Yao Xiao , Qiuyan Lin , Wenyue Fang , Rui Zhang

This paper employs an adaptive finite element limit analysis (AFELA) combined with nonlinear programming (NLP) to investigate the seismic bearing capacity of strip footings overlying cavities in rock masses that obey the generalized Hoek–Brown (GHB) failure criterion. The feasible arc interior point algorithm (FAIPA) is utilized to solve the optimization models, and a novel imprecise step search algorithm is introduced to improve the NLP convergence. Based on the self-developed AFELA procedure, the bearing capacity reduction factor R of strip footing on a rock mass has been calculated, with the results presented in tables and charts. Parametric analysis reveals that a footing centered above a cavity does not exhibit the lowest capacity, likely due to a beneficial arching effect. Failure modes associated with varying parameters are also discussed, and the results show that increasing the horizontal seismic coefficient reduces the extent of the failure zone.

本文采用自适应有限元极限分析（AFELA）和非线性规划（NLP）相结合的方法，研究了岩体中服从广义Hoek-Brown （GHB）破坏准则的覆空条形基础的抗震承载力。采用可行弧内点算法（FAIPA）求解优化模型，并引入一种新的不精确步进搜索算法来提高NLP的收敛性。基于自行开发的AFELA程序，计算了岩体条形基础的承载力折减系数R，并以表格形式给出了计算结果。参数分析表明，以空腔为中心的基础并没有表现出最低的承载力，这可能是由于有益的拱效应。结果表明，水平地震系数的增大减小了破坏区范围。

引用次数: 0

An experimental and theoretical research on shield screw conveyor discharging efficiency in moderately weathered mudstone strata and its influence on clogging 中等风化泥岩地层中盾构螺旋输送机卸料效率及其对堵塞影响的实验与理论研究

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-08-26 DOI: 10.1016/j.sandf.2025.101675

Bin Zhuo, Yong Fang, Liupan Dou, Xuedan Liu, Muyuan Zhu, Xiongyu Hu

When an earth pressure balance shield machine is tunneling in cohesive soils, a poorly effective soil conditioning scheme often leads to clogging in the cutterhead and the screw conveyor, which reduces tunneling efficiency and may even cause the shield machine to stop tunneling. Different from the conventional test method that use artificial clay soil, this study relies on the field shield engineering in mudstone strata and conducts soil conditioning tests using the field soil as the basic material. Using a shield soil migration model test, the whole process of clogging in a screw conveyor is reproduced, and the pattern of migration change of soil in the screw conveyor is obtained. The screw conveyor torque decreases with the increase of foam injection rate. When the slump of soil reaches 15 cm, the torque tends to be stable. Based on this, this study innovatively establishes a theoretical calculation model that can quantitatively describe the relationship between the soil discharge and the pressure gradient. Experimental verification shows that this model can not only quantitatively describe the variation laws of the soil discharge and the pressure gradient, but also qualitatively reveal the influence mechanism of the soil chamber pressure and soil fluidity on the discharge efficiency. Finally, using the Ziyang line of the Chengdu rail transit as a field test, it is found that under the recommended soil conditioning scheme, the clogging problem in the shield cutterhead and screw conveyor is greatly reduced and the efficiency of shield tunneling is significantly improved.

土压平衡盾构机在粘性土中掘进时，如果土壤调理方案效果不佳，往往会导致刀盘和螺旋输送机堵塞，降低掘进效率，甚至可能导致盾构机停止掘进。与常规使用人工粘土的试验方法不同，本研究依托泥岩地层的现场盾构工程，以现场土为基本材料进行土壤调理试验。通过盾构土迁移模型试验，再现了螺旋输送机内土体堵塞的全过程，得到了土体在螺旋输送机内的迁移变化规律。螺旋输送机扭矩随泡沫注入量的增加而减小。当土体坍落度达到15 cm时，扭矩趋于稳定。在此基础上，本研究创新性地建立了定量描述土流量与压力梯度关系的理论计算模型。实验验证表明，该模型不仅可以定量描述土流量和压力梯度的变化规律，而且可以定性地揭示土室压力和土壤流动性对泄放效率的影响机理。最后，以成都轨道交通紫阳线为现场试验，发现在推荐的土壤调节方案下，盾构刀盘和螺旋输送机的堵塞问题大大减少，盾构掘进效率显著提高。

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引用次数: 0

Slaking mechanisms of a mudstone and prediction of its number-size distribution considering shape evolution 考虑形态演化的泥岩溶蚀机理及数粒分布预测

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-09-05 DOI: 10.1016/j.sandf.2025.101682

Danxi Sun , Hailong Wang , Hideo Komine , Guojun Cai , Gaofeng Pan , Daichi Ito

The wide distribution of mudstone poses challenges to efficient construction and safe long-term maintenance of infrastructure, primarily due to its susceptibility to slaking. To explore the slaking mechanisms, cyclic wetting–drying slaking tests under both atmospheric and vacuum conditions were conducted on natural mudstone collected from Akita Prefecture, Japan. A multi-view approach was employed to capture the evolution of three-dimensional particle shape, enabling quantitative analysis of slaking mechanisms and the development of number-size and surface area-size distribution models that account for shape effects. The results indicate that the atmospheric slaking proceeds more rapidly than vacuum slaking tests, attributed to the elimination of the air-breakage phenomenon. Shape evolution analysis reveals that the shell-like medium-sized particles possess higher specific surface areas, resulting from the typical layered slaking phenomenon observed during slaking. These layered fragments are attributed to differential swelling, driven by non-uniform moisture distribution in the specimens. The contribution of this mechanism is validated and quantitatively assessed through a comparative analysis of particle shape compositions across different slaking conditions. Finally, particle shape evolution is integrated into predictive models for number-size and surface area-size distributions. The performance of these models is verified against experimental measurements.

泥岩的广泛分布给基础设施的高效建设和长期安全维护带来了挑战，主要是由于泥岩易滑脱。为探索泥岩的熟化机理，在常压和真空条件下对日本秋田县天然泥岩进行了干湿循环熟化试验。采用多视角方法捕捉三维颗粒形状的演变，实现了对松弛机制的定量分析，并建立了考虑形状效应的数量-尺寸和表面积-尺寸分布模型。结果表明，由于消除了空气破碎现象，常压熟化试验比真空熟化试验进行得更快。形状演化分析表明，壳状中等颗粒具有较高的比表面积，这是由于在熟化过程中观察到典型的分层熟化现象所致。这些层状碎片是由于试样中水分分布不均匀造成的差异膨胀。这一机制的贡献是验证和定量评估，通过比较分析颗粒形状组成在不同的软化条件。最后，将颗粒形状演变整合到数量-尺寸和表面积-尺寸分布的预测模型中。通过实验验证了这些模型的性能。

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引用次数: 0

Characteristics and modelling of coral sand particle breakage under principal stress axis rotation 主应力轴旋转作用下珊瑚砂颗粒破碎特性及模型

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-08-12 DOI: 10.1016/j.sandf.2025.101666

Zhangqing Xuan , Yanyan Cai , Jin Yu , Peng Xue

To investigate the stress–strain characteristics and particle breakage laws of coral sand under the rotation of the principal stress axis—Objectives, the triaxial test and the principal stress axis rotation test were conducted on coral sand with varying consolidation confining pressures and compactness—Methods. Furthermore, a particle breakage model considering the irregularity and non-uniformity inherent in coral sand was established. The results show that: (1) Scanning electron microscopy (SEM) analysis and triaxial test demonstrates that the coral sand has strong non-coaxial characteristics. Both increased compactness and confining pressure enhance the strength of coral sand; (2) Coral sand undergoes shear expansion followed by gradual compression in triaxial shear, and demonstrates body shrinkage when its compactness is relatively high. The broken particles of coral sand are mainly large particles, small particles are less broken or not broken, and the disappearance of prism is the main type of particle breakage; (3) The form of particle breakage in coral sand under rotation of the principal stress axis is mainly grinding—Key Findings. The irregularity and non-uniformity of coral sand can be represented with the equivalent of non-coaxiality in the deformation and breakage process of the principal stress axis rotation, and a mathematical model has been established to characterize the breakage behavior of coral sand particles. Impressively, The model demonstrates high accuracy in predicting particle breakage under principal stress rotation (average error < 5 %).

为研究主应力轴旋转作用下珊瑚砂的应力-应变特性及颗粒破碎规律，对不同固结围压和压实度的珊瑚砂进行了三轴试验和主应力轴旋转试验。在此基础上，建立了考虑珊瑚砂内部不规则性和非均匀性的颗粒破碎模型。结果表明：(1)扫描电镜（SEM）分析和三轴试验表明，珊瑚砂具有较强的非同轴特性。压实度和围压的增加均可提高珊瑚砂的强度；(2)珊瑚砂在三轴剪切过程中经历剪切膨胀后逐渐压缩，在密实度较高时表现为体收缩。珊瑚砂破碎颗粒以大颗粒为主，小颗粒较少破碎或未破碎，棱柱消失是颗粒破碎的主要类型；(3)在主应力轴旋转作用下，珊瑚砂颗粒破碎形式主要为磨粒破碎。珊瑚砂的不规则性和非均匀性可以用主应力轴旋转变形破坏过程中的非同轴性等效来表示，并建立了表征珊瑚砂颗粒破坏行为的数学模型。令人印象深刻的是，该模型在预测主应力旋转下的颗粒破碎方面显示出很高的准确性(平均误差<；5%)。

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引用次数: 0

Laboratory experiments on small-scale freezing sampling method for sand 砂土小尺度冻结取样方法的室内试验研究

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-09-05 DOI: 10.1016/j.sandf.2025.101657

Pei-Chen Hsieh , Takashi Kiyota , Toshihiko Katagiri , Masataka Shiga , Manabu Takemasa , Ryohei Kobayashi

The need to collect high-quality undisturbed samples to accurately determine in-situ liquefaction resistance of sandy soils in laboratory tests is widely recognized. Decades ago, the freezing sampling method was developed to minimize sample disturbance by pre-freezing the ground. However, due to the large scale and high cost of the work, this method is rarely used in common geotechnical surveys. To address this issue, a small-scale freezing sampling method has recently been developed. It reduces the sampling time and amount of required coolant, and can be applied to conventional borehole surveys. On the other hand, the quality of the samples collected by this new method has not been properly assessed. In this study, therefore, the appropriate conditions for inserting the freezing tube with the help of a cylindrical sand column were discussed, and the small-scale freezing sampling method was successfully implemented in a calibration chamber, whereby hollow cylindrical frozen samples with an outer diameter of 100 mm were collected within approximately 40 min and using only about 70 kg of liquid nitrogen. The focus of the quality assessments of the collected frozen samples was placed on the density and shear wave velocity measurements. The results showed that the changes in the small strain shear moduli were −0.5 % between the stages before and after the sampling, suggesting that the implementation of small-scale freezing sampling can be expected to improve the accuracy of in-situ liquefaction resistance estimates and, in turn, the accuracy of liquefaction assessments.

在实验室测试中，需要收集高质量的原状样品来准确地测定沙土的原位液化阻力，这一点已得到广泛认识。几十年前，冻结取样法是通过对地面进行预冻结来减少取样扰动而发展起来的。但由于工程规模大、成本高，在普通岩土工程勘察中很少采用该方法。为了解决这一问题，最近开发了一种小规模冷冻取样方法。它减少了采样时间和所需冷却剂的量，可以应用于常规的井眼测量。另一方面，用这种新方法采集的样品的质量还没有得到适当的评价。因此，本研究探讨了利用圆柱形砂柱插入冷冻管的适宜条件，并在校准室中成功实施了小规模冷冻取样方法，在大约40分钟内收集了外径为100 mm的空心圆柱形冷冻样品，仅使用了约70 kg的液氮。冰冻样品的质量评价重点放在密度和横波速度的测量上。结果表明，取样前后的小应变剪切模量变化幅度为- 0.5%，表明实施小规模冻结取样有望提高现场液化阻力估算的准确性，进而提高液化评估的准确性。

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引用次数: 0

Study on the hydraulic characteristics of natural levees by field surveys: Case study of the Kokai River, Japan 自然堤防水力特性的野外调查研究——以日本Kokai河为例

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-09-02 DOI: 10.1016/j.sandf.2025.101679

Wenyue Zhang , Mai Tabuchi , Tomotaka Yoshikawa , Akihiro Takahashi

As compensation for the limited experimental data from the borehole logs, geological knowledge is expected to contribute to better risk assessment of the river levee system. Although natural levees have long been recognized as related to the underseepage risk of river levees, limited quantitative knowledge of hydraulic characteristics is available. Field surveys are conducted at a site along the Kokai River in Japan to reveal the hydraulic characteristics of natural levee sediments. Sounding tests allow us to capture laminar structures in the natural levee sediments. Through in-situ seepage tests, it is found that the silty materials in the natural levee sediments have hydraulic conductivity in the order of around E-06 m/s. Based on the results from the field surveys, numerical spatial hydraulic conductivity models of natural levees are built by applying geostatistical methods, including indicator Kriging and indicator simulations. The methodology in this study shows a possibility of quantifying geological knowledge, which finally contributes to the quantitative risk assessment against underseepage and internal erosion.

作为钻孔测井实验数据有限的补偿，地质知识有望有助于更好地对河流堤防系统进行风险评估。虽然自然堤防长期以来被认为与河流堤防的下渗风险有关，但水力特性的定量知识有限。为了揭示天然堤防沉积物的水力特性，在日本Kokai河沿岸进行了实地调查。探空试验使我们能够捕捉到天然堤防沉积物中的层流结构。通过现场渗流试验发现，天然堤防沉积物中的粉质材料具有E-06 m/s左右的水力导率。在野外调查结果的基础上，应用地质统计学方法，包括指标克里格法和指标模拟法，建立了天然堤坝的空间水力导率数值模型。本研究的方法显示了量化地质知识的可能性，最终有助于定量评估地下渗透和内部侵蚀的风险。

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引用次数: 0

In-situ investigation on installation mechanisms of pre-bored grouted planted piles in deep and thick sand layers 深厚砂层中预钻孔灌注桩安装机理的现场研究

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-08-29 DOI: 10.1016/j.sandf.2025.101678

Jingwei Zhang , Zhencai Luo , Yunlong Liu , Bowen Zheng , Zhenguo Hou , Jin Kong

Due to merits of low noise and vibration, the pre-bored planted method has been widely used in engineering practice to assist the installation of the prestressed high-strength concrete (PHC) piles in area where deep and thick sand layers are commonly encountered. However, the research on the influence mechanism of pile driving methods in hard soil layers mainly focuses on the static pressing method and the hammering method, while the penetration characteristics under pre-bored assistance remains unclear. Therefore, a full-scale field test was conducted to investigate the installation effects. The penetration mechanisms of the piles with pre-bored assistance in areas with a deep and thick sand layer was discussed. Besides, an analytical method was proposed to predict the energy (hammer blow counts) necessary to drive pile to design depth. The results showed that the pre-bored grouted planted method significantly reduced the energy required for pile driving, compared to both the hammering method and the pre-bored planted method. This was because pre-drilling reduced displaced soil volume and relieved lateral stress. The pile load transfer mechanism was optimized by pre-drilling, which effectively leveraged the high compressive strength of the deep and thick sand layers. Meanwhile, the shaft friction within the grouted depth was significantly enhanced by the permeation, cementation and reinforcement effects of the concrete slurry, thereby improving the pile bearing capacity. Furthermore, the analytical method proposed based on the cavity expansion theory was capable of predicting the energy required for pile driving, which could guide the selection of pile driving equipment with minimum energy consumption and prevent pile damage caused by excessive hammering.

预钻孔灌注法由于具有低噪声、低振动的优点，在工程实践中广泛应用于深厚砂层地区的预应力高强混凝土桩的辅助安装。然而，硬土层中打桩方式影响机理的研究主要集中在静压法和锤击法，预钻辅助下的沉贯特性尚不清楚。因此，进行了全尺寸的现场试验来研究安装效果。探讨了预钻辅助桩在深厚砂层地区的侵彻机理。此外，提出了一种预测打入桩至设计深度所需能量（锤击次数）的分析方法。结果表明，与锤击法和预钻孔灌注法相比，预钻孔灌注法明显降低了打桩所需的能量。这是因为预钻减少了位移土体积，减轻了侧向应力。通过预钻优化桩基荷载传递机制，有效利用深、厚砂层的高抗压强度。同时，在灌浆深度内，混凝土浆体的渗透、胶结和加固作用显著增强了桩身摩擦力，从而提高了桩身承载力。此外，基于空腔扩展理论提出的分析方法能够预测打桩所需的能量，可以指导选择能耗最小的打桩设备，防止过度锤击造成桩的损坏。

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引用次数: 0

Experimental and numerical study on helical piles in aeolian sand: bearing behavior and design methods 风沙中螺旋桩的试验与数值研究：承载性能与设计方法

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-09-01 Epub Date: 2025-08-22 DOI: 10.1016/j.sandf.2025.101680

Yongping Li , Songzhao Qu , Jing Bai , Dongming Yang , Sangtian Hu , Lefu Di , Ruiyuan Han , Yijin Wu , Yuan Xiang , Dapeng Wang , Yi Zhang , Yonghua Guo , Zhe Zhang

In aeolian sand, the mechanical behavior of helical anchors involves complex performance evolution mechanisms that are not yet fully understood. This study employs a multi-scale integrated approach combining field tests, numerical simulations, and machine learning to systematically investigate the evolution laws of the bearing behavior of helical anchors. The results indicate: (1) The critical embedment depth threshold for helical anchors in aeolian sand is H = 5D; beyond this threshold, the load direction effect can be neglected. (2) Multi-plate helical anchors exhibit significant geometrically nonlinear superposition behavior. Dense spacing (S/D < 4) produces notable stress superposition effects (η = 1.15–1.32), whereas wide spacing (S/D ≥ 4) results in independent bearing units (η = 0.97–1.03). (3) The XGBoost machine learning model identifies the internal friction angle, anchor plate diameter, and embedment depth ratio as the most influential features affecting bearing capacity. Based on these control parameters, predictive equations for the bearing capacity coefficient N_q and soil lateral friction coefficient K_u were developed, with predictions showing excellent agreement with experimental data. This provides engineers with a reliable analytical framework for performance-based design. The study not only deepens the understanding of the behavioral mechanisms of helical piles in aeolian sand but also offers practical solutions for geotechnical engineering practice.

在风沙中，螺旋锚的力学行为涉及复杂的性能演化机制，目前尚未完全了解。本研究采用现场试验、数值模拟和机器学习相结合的多尺度综合方法，系统研究螺旋锚杆承载行为的演化规律。结果表明：(1)螺旋锚在风沙中的临界嵌入深度阈值为H = 5D；超过这个阈值，载荷方向效应可以忽略不计。(2)多板螺旋锚具有显著的几何非线性叠加行为。密间距（S/D < 4）产生显著的应力叠加效应（η = 1.15 ~ 1.32），宽间距（S/D≥4）产生独立的承载单元（η = 0.97 ~ 1.03）。(3) XGBoost机器学习模型识别出内摩擦角、锚板直径和嵌入深度比是影响承载力的最重要特征。基于这些控制参数，建立了承载力系数Nq和土侧摩擦系数Ku的预测方程，预测结果与试验数据吻合良好。这为工程师提供了基于性能的设计的可靠分析框架。该研究不仅加深了对风沙中螺旋桩行为机理的认识，而且为岩土工程实践提供了切实可行的解决方案。

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引用次数: 0