Soils and Foundations最新文献_第2页

Macroscale and microscale triaxial compressive behaviors of loose saturated sand under excess pore water pressure generation 超孔隙水压力作用下松散饱和砂宏、微尺度三轴压缩特性

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-01-19 DOI: 10.1016/j.sandf.2025.101725

Ryunosuke Kido , Yuya Ohtani , Yosuke Higo

Investigating the triaxial compressive behavior of loose saturated sand under excess pore water pressure generation, based on both macroscale and microscale observations, contributes to a better understanding of the instability mechanisms associated with the non-localized failure mode. In this study, the original intention was to conduct undrained triaxial tests on dense and loose saturated sands. However, due to the unavoidable limitations associated with X-ray CT imaging, the tests were consequently conducted under a partially drained condition. Nevertheless, the use of X-ray CT imaging, combined with image analyses, revealed clear differences in both the macroscopic responses and microscale structural evolution between dense and loose saturated sands that exhibit localized and non-localized failure modes. The loose sand examined in the present study showed a gradual increase in deviator stress until the end of shearing. During this process, the local void ratio gently decreased and the number of particle contacts gently increased due to compression. The particle-contact orientation did not change significantly from the initial state to the end of shearing. Shear strain was found to be relatively uniformly distributed over a wide region in the loose sand specimens. It is likely that these deformation characteristics of loose sand correspond to positive second-order work, indicating the stable state of the material. This behavior was clearly different from that of the dense sand specimens, for which significant dilation, a decrease in the number of particle contacts, and a change in the particle-contact orientation that occurred, were associated with a localized failure mode characterized by negative second-order work.

基于宏观尺度和微观尺度的观察，研究饱和松散砂在超孔隙水压力下的三轴压缩行为，有助于更好地理解与非局部破坏模式相关的失稳机制。本研究的初衷是对致密和松散饱和砂进行不排水三轴试验。然而，由于x射线CT成像不可避免的局限性，因此测试是在部分排水的条件下进行的。然而，使用x射线CT成像结合图像分析，揭示了致密和松散饱和砂的宏观响应和微观结构演化的明显差异，表现为局部和非局部破坏模式。本研究检测的松散砂在剪切结束前，偏应力逐渐增大。在此过程中，由于压缩作用，局部孔隙率逐渐降低，颗粒接触次数逐渐增加。从初始状态到剪切结束，颗粒接触取向没有明显变化。剪切应变在较宽的区域内相对均匀地分布。松散砂土的这些变形特征很可能对应于正二阶功，表明材料处于稳定状态。这种行为明显不同于致密砂试件，在致密砂试件中，显著的膨胀、颗粒接触数量的减少和颗粒接触方向的改变与负二阶功特征的局部破坏模式有关。

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引用次数: 0

Investigating the liquefaction resistance and initial shear modulus of silty sands from equivalent intergranular void ratio concept 从等效粒间空隙比的概念研究粉质砂的液化阻力和初始剪切模量

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-02-09 DOI: 10.1016/j.sandf.2025.101726

F. Shi , H. Kaneko , M. Maeda , T. Ishimaru , Y. Tsukamoto

Multiple series of laboratory undrained cyclic triaxial tests and bender element tests are conducted to obtain pairing data for R_l and G_o for laboratory reconstituted samples of silty sands. Several categories of silty sands in a ‘fines in sand’ matrix are prepared using coarse, medium, and fine sands as the host sands and non-plastic fines with different fines contents of F_c = 0–30% as the guest silt. The concept of the equivalent intergranular void ratio is that it is used to deduce the b-values for R_l and G_o. Instead of applying the empirical expression, as employed in past studies, the b-values are determined by directly fitting the silty sand data to the corresponding backbone clean sand relation. The fictitious active fines content, defined as F_c* = bF_c, is then introduced, which bears a good physical meaning for mechanical interpretations of the test results. F_c* tends to increase rapidly as F_c increases, following the empirical expression of F_c* = μF_c². The corresponding values for F_c.l* and F_c.s* for large-strain R_l and small-strain G_o, respectively, are directly compared. It is found that they take different values, and that the ratio of F_c.l*/F_c.s* is dependent on the size disparity ratio for χ and F_c. The implications of this experimental finding are discussed with respect to the micromechanical modelling of the silty sand behaviour. The differences in the values for F_c.l* and F_c.s* are found to lead to multiple series of cyclic resistance ratio CRR and shear wave velocity V_s relations for silty sands with different F_c, which are comparable to the empirical relations given in past studies.

通过室内不排水循环三轴试验和弯曲单元试验，获得了粉质砂室内重构样的Rl和Go的配对数据。以粗砂、中砂和细砂为主砂，以Fc = 0-30%的非塑性细砂为客砂，制备了“砂中细砂”基质中的几种粉砂。等效晶间空隙比的概念是用来推导Rl和Go的b值。与以往研究中采用的经验表达式不同，b值是通过将粉砂数据直接拟合到相应的主干净砂关系来确定的。然后引入虚拟的活性细粒含量，定义为Fc* = bFc，这对于测试结果的力学解释具有良好的物理意义。Fc*随Fc的增大而迅速增大，符合Fc* = μFc2的经验表达式。Fc对应的值。l*和Fc。s*分别为大应变Rl和小应变Go的直接比较。发现它们取不同的值，且Fc.l*/Fc。s*取决于χ和Fc的大小差比。这一实验发现的含义讨论了关于粉砂行为的微观力学模型。Fc值的差异。l*和Fc。发现s*导致不同Fc粉质砂的循环阻力比CRR和剪切波速Vs关系的多个序列，与以往研究中给出的经验关系相当。

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引用次数: 0

Numerical insight into twin tunnelling-induced soil-structure interaction in battered pile-supported systems under lateral loading 横向荷载作用下双隧道冲击桩支护体系土-结构相互作用的数值分析

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-01-30 DOI: 10.1016/j.sandf.2026.101747

Mukhtiar Ali Soomro, Sharafat Ali Darban

With rapid increasing urbanization, the construction of twin tunnels adjacent to existing foundations has become common in underground development projects. This study investigates the influence of twin parallel tunnelling on elevated battered pile group and battered piled raft subjected to lateral loading in soft clay. A series of three-dimensional coupled consolidation finite element analyses, incorporating an advanced hypoplastic clay model with small-strain stiffness are carried out. The model parameters are validated using centrifuge test data to ensure realistic simulation of tunnelling-induced ground deformations. Twin tunnels are positioned at varying depths relative to the battered piled foundation: neat the shaft, near the toe, and below the toe of the piles. Results reveal that the largest lateral displacements and differential settlements occur when tunnelling is near the pile toe. The second tunnel further increases movement toward the first tunnel due to degraded ground stiffness. Compared to elevated battered pile groups, battered piled rafts exhibit significantly reduced lateral displacements, deflections, and settlements because of additional resistance from raft-soil interaction. Twin tunnelling in each case also alters axial load distribution. Twin tunnelling near pile shaft caused reduction of 61% in shaft resistance whereas 20% of end-bearing decreased in twin tunnelling near pile toe. The maximum bending moments were induced near the pile head in battered elevated pile group but are smaller in piled rafts (up to 30% reduction) in each case.

随着城市化的快速发展，在地下开发项目中，在既有基础上修建双隧道已成为一种普遍现象。研究了双平行隧道开挖对软土中受侧向荷载作用的高架破桩群和破桩筏的影响。采用先进的小应变刚度欠塑性粘土模型，进行了一系列三维耦合固结有限元分析。利用离心试验数据对模型参数进行了验证，保证了隧道开挖引起的地面变形模拟的真实性。双隧道的位置相对于破损的桩基有不同的深度：在竖井附近，在桩趾附近，在桩趾以下。结果表明，在桩端附近开挖时，桩侧位移最大，沉降差最大。由于地面刚度降低，第二条隧道进一步增加了向第一条隧道的移动。与高架桩群相比，由于筏-土相互作用的额外阻力，受损桩筏表现出显著减少的侧向位移、挠度和沉降。两种情况下的双隧道开挖也会改变轴向荷载的分布。靠近桩身的双隧道施工使桩身阻力降低61%，靠近桩脚的双隧道施工使端承降低20%。在受冲击的高架桩群中，最大弯矩在桩顶附近产生，而在桩筏中，最大弯矩减小30%。

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引用次数: 0

Polyacrylamide improves the strength of peat soil while reducing cement consumption: An experimental and machine learning investigation 聚丙烯酰胺提高泥炭土的强度，同时减少水泥消耗：一项实验和机器学习研究

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-01-23 DOI: 10.1016/j.sandf.2026.101745

Yangshou Yu , Zhiliang Wang , Miao Li , Lei Lang , Linfang Shen , Yang Yu

Peat soil presents poor geotechnical properties, posing significant risks to structural stability when used as a foundation material. This study investigates the potential of polyacrylamide (PAM) as an adhesive additive to enhance the strength of peat soil stabilized with cement and sand. Unconfined compressive strength (UCS) tests were conducted to evaluate PAM’s effectiveness, complemented by microscopic analyses to explore underlying improvement mechanisms. Results show that PAM significantly increases soil strength, with higher PAM content yielding greater gains. Specifically, adding 10 % PAM boosts the UCS of untreated peat soil by up to 2.5 times and improves the strength of peat soil treated with 30 % cement and 30 % sand by 174.1 kPa. PAM also reduces soil permeability without exhibiting ecotoxicity. Microscopic observations reveal that PAM forms cross-linked gel networks that bind soil particles into large aggregates. 10 % PAM decreases the specific surface area, pore volume, and average pore size by 32.6 %, 42.2 %, and 21.4 %, respectively. Importantly, PAM does not alter the chemical composition of the stabilized soil and remains stable over time. Finally, a gene expression programming (GEP) algorithm was used to develop a predictive mathematical model for UCS, achieving a coefficient of determination (R²) above 0.97. An analysis of cement consumption using this model indicates that incorporating 10 % PAM can reduce cement consumption by 26.1 % to achieve a target strength of 300 kPa, compared with using only cement and sand. These findings demonstrate that PAM is an effective and environmentally beneficial stabilizer for peat soil.

泥炭土具有较差的岩土力学特性，当用作地基材料时，对结构稳定性构成重大风险。本研究探讨了聚丙烯酰胺（PAM）作为粘接添加剂对水泥和砂土稳定泥炭土强度的增强潜力。通过无侧限抗压强度（UCS）测试来评估PAM的有效性，并辅以微观分析来探索潜在的改进机制。结果表明，PAM能显著提高土壤强度，PAM含量越高，收益越大。具体而言，添加10% PAM可使未处理泥炭土的单抗强度提高2.5倍，使30%水泥和30%沙子处理的泥炭土强度提高174.1 kPa。PAM还能降低土壤渗透性而不表现出生态毒性。微观观察表明，PAM形成交联凝胶网络，将土壤颗粒结合成大的聚集体。10%的PAM比表面积、孔体积和平均孔径分别降低32.6%、42.2%和21.4%。重要的是，PAM不会改变稳定土壤的化学成分，并随着时间的推移保持稳定。最后，利用基因表达编程（GEP）算法建立UCS预测数学模型，确定系数（R2）在0.97以上。使用该模型对水泥消耗量进行的分析表明，与仅使用水泥和砂相比，加入10%的PAM可以减少26.1%的水泥消耗量，以达到300 kPa的目标强度。这些结果表明，PAM是一种有效的环境友好型泥炭土稳定剂。

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引用次数: 0

Evaluation of the relationship between freezing point and suction of sodium sulfate loess near 0°C 0℃附近硫酸钠黄土凝固点与吸力关系的评价

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-02-09 DOI: 10.1016/j.sandf.2026.101753

Songhe Wang , Yang Wang , Yuhang Liu , Jiading Wang , Jiulong Ding , Xiaoliang Yao

Correlation between freezing point and suction of sodium sulfate loess upon phase change is fundamental for understanding the mechanism of salt weathering of check dams in Loess Plateau of China. Given the ongoing controversies over frozen soil suction measurement, soil suction test near 0°C was employed as a compromise to link with freezing point. The test data from vapor equilibrium technique (VET) and the TEROS-21 Gen 2 soil water potential sensor were combined with the reported data to derive a temperature-dependent calibration model from the correspondence between the suction and the equilibrium water content of Whatman No. 42 filter paper. This model holds the merits of robust accuracy, simple structure with merely two parameters to be calibrated, and the capacity to capture the temperature effect on the calibration curve. The freezing point of sodium sulfate loess is closely linked to the suction at 0.5°C. Both matric and osmotic suctions do not linearly superimpose on the freezing point but exhibit a coupling effect. A modified Mizoguchi model was accordingly developed and verified for five types of saline loess. The results will throw light on the nature of salt weathering of check dams and are also encouraging for targeted treatments.

硫酸钠黄土的凝固点和吸力随相变化的相关性是认识黄土高原淤土坝盐风化机理的基础。考虑到目前对冻土吸力测量的争议，我们采用接近0°C的土壤吸力试验作为妥协，与凝固点联系起来。将蒸汽平衡技术（VET）和TEROS-21 Gen 2土壤水势传感器的测试数据与报告数据相结合，根据Whatman 42号滤纸的吸力与平衡含水量之间的对应关系，推导出温度相关的校准模型。该模型具有精度高、结构简单、只有两个参数需要校准、能够捕捉温度对校准曲线的影响等优点。在0.5℃时，硫酸钠黄土的冰点与吸力密切相关。基质吸力和渗透吸力在凝固点上不是线性叠加的，而是表现出耦合效应。在此基础上，建立了5种盐渍黄土的修正沟口模型并进行了验证。这一结果将有助于揭示挡沙坝盐风化的本质，并鼓励有针对性的治疗。

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引用次数: 0

Special issue on climate change adaptation and innovation from geotechnical perspectives 从岩土工程角度探讨气候变化适应与创新的专题

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-02-04 DOI: 10.1016/j.sandf.2026.101744

Hemanta Hazarika (Guest Editor)

引用次数: 0

Failure area change estimation and tunnel face pressure characteristics of large soil-covering tunnel tests 大型覆土隧道试验破坏区变化估算及工作面压力特征

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-01-12 DOI: 10.1016/j.sandf.2025.101723

Ryo Kawanoue , Yota Togashi , Masahiko Osada , Jiro Kuwano

Estimating the tunnel face earth pressure is essential for determining the limit support pressure in shield tunneling and for urban mountain tunnels in Japan. To meet these demands, limit equilibrium methods for calculating tunnel face pressures remain extremely important methods of calculation in tunneling practice. In limit equilibrium calculations, the appropriate setting of the failure zone prism affects the accuracy. It is crucial to properly account for changes in the height of the failure zone prism due to the frictional resistance of the ground. In this study, an improved simple method is proposed for estimating the height of the failure zone prism. The method utilizes a versatile logistic equation to describe the relationship between the soil cover and the prism height. The proposed method is a model in which the height of the failure zone prism converges to a constant value in the logistic equation as the soil cover increases, indicating an increase in frictional resistance. To validate the proposed method, tunnel tests with large soil cover ratios up to

C / D = 10

in a 1 g field are conducted, and changes in the failure zone prism and the nature of the soil pressure are determined. As a result of the tunnel tests, the width of the failure zone can be approximately expressed by the width of the wedge derived under the condition of active earth pressure. The face pressure at the initial stage of tunnel pulling in the tunnel tests is proportional to the soil cover pressure when the soil cover is small. On the other hand, as the soil cover increases, it shows a value between the earth pressure at rest and the active earth pressure. This is thought to be due to the fact that the frictional resistance of the ground increases in proportion to the soil cover. Furthermore, the height of the failure zone prism, identified by a PIV (particle image velocimetry) analysis, can be adequately represented by the proposed method. An example of how the proposed equation can be incorporated into a simple limit equilibrium calculation is described, and it is shown that the results of this calculation can properly evaluate the experimental results.

隧道工作面土压力的估算是确定盾构隧道和日本城市山地隧道极限支护压力的基础。为了满足这些要求，极限平衡法计算巷道工作面压力仍然是隧道施工实践中极为重要的计算方法。在极限平衡计算中，失效区棱柱的合理设置会影响计算精度。这是至关重要的，以适当地考虑在破坏区棱镜的高度变化，由于地面的摩擦阻力。本文提出了一种改进的简单方法来估计失效区棱镜的高度。该方法利用一个通用逻辑方程来描述土壤覆盖与棱镜高度之间的关系。所提出的方法是一个模型，在logistic方程中，随着土壤覆盖面积的增加，破坏区棱柱的高度收敛于一个常数，表明摩擦阻力的增加。为了验证该方法的有效性，在1 g条件下进行了大覆盖比（C/D=10）的隧道试验，并对破坏区棱柱的变化和土压力的性质进行了分析。隧道试验结果表明，在主动土压力条件下，破坏区宽度可近似表示为楔形板宽度。隧道试验中隧道拉拔初始阶段的工作面压力与土覆盖压力成正比。另一方面，随着覆盖面积的增加，静止土压力与活动土压力之间存在一个值。这被认为是由于地面的摩擦阻力与土壤覆盖成比例地增加。此外，通过PIV（粒子图像测速）分析，该方法可以充分表示故障区棱镜的高度。文中给出了将所提方程与简单的极限平衡计算相结合的实例，结果表明，所提方程的计算结果能较好地评价实验结果。

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引用次数: 0

Effect of gradation characteristics on seepage failure in foam-conditioned gap-graded soils for EPB shield tunneling 级配特性对盾构隧道泡沫条件下裂隙级配土渗流破坏的影响

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-02-02 DOI: 10.1016/j.sandf.2026.101748

Bin Wang , Shuying Wang , Xiangcou Zheng , Xinggao Li , Fei Ye

Muck spewing at the screw conveyor outlet in water-rich coarse-grained soils poses a significant risk to the efficiency and safety of shield tunneling. This study systematically investigates the influence of gradation characteristics on the seepage failure behavior of foam-conditioned gap-graded soils through vertical upward hydraulic tests. The effects of fines content, gap ratio, and foam injection ratio on failure modes and hydraulic responses are examined. Results show that the seepage failure mode is jointly controlled by the combined effects of particle size distribution, fines content, and foam injection. Changes in the gap ratio can trigger transitions between piping and heave failure, and excessively high foam injection can destabilize soil during heave. The pore structure, regulated by gradation, determines the stability of foam within the soil, with a sufficient proportion of fine particles essential for maintaining internal stability and mitigating seepage erosion. These findings provide insights into the mechanisms by which gradation characteristics influence seepage failure and offer guidance for foam conditioning practices in shield tunneling, supporting the theoretical modeling of critical hydraulic gradients in foam-conditioned soils.

在富水的粗粒土中，螺旋输送机出料口的排渣对盾构施工的效率和安全造成重大威胁。通过纵向上向水力试验，系统研究了级配特性对泡沫条件下裂隙级配土渗流破坏行为的影响。研究了细粒含量、间隙比和泡沫注入比对破坏模式和水力响应的影响。结果表明：渗流破坏模式受颗粒粒径分布、细粒含量和泡沫注入等因素的共同控制；间隙比的变化会引发管胀破坏与鼓胀破坏之间的过渡，过高的泡沫注入会导致土体在鼓胀过程中失稳。孔隙结构受级配调节，决定了土壤内部泡沫的稳定性，足够比例的细颗粒对于保持内部稳定性和减轻渗流侵蚀至关重要。这些发现有助于深入了解级配特性影响渗流破坏的机制，并为盾构隧道的泡沫调节实践提供指导，支持泡沫调节土中临界水力梯度的理论建模。

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引用次数: 0

Experimental and numerical study on dynamic responses of three-story building supported by T-BAGS base isolation and vibration control system t - bag基础隔振控制系统支撑三层建筑动力响应的试验与数值研究

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-02-12 DOI: 10.1016/j.sandf.2026.101741

Ali Vakilazadsarabi , Kinji Takeuchi , Yasuo Tomono , Tatsunori Matsumoto

T-BAGS is a seismic base isolation and vibration control system. It is composed of two stacked layers of geotextile sandbags filled with sand. A slip sheet is sandwiched between the upper and lower sandbags to control the slippage between them. Slipping between the upper and lower sandbags works as base isolation. Furthermore, the hysteretic shear deformation of each sandbag plays a role in vibration control. In this research, the static and dynamic behaviors of the T-BAGS system are firstly investigated through laboratory tests, including simple shear tests on one sandbag and shaking table tests on six sets of T-BAGS. Then, dynamic numerical analyses of the shaking table tests are conducted. Based on the results, dynamic 3D analyses of a 3-story residential RC building, subjected to a severe earthquake, are conducted with and without the T-BAGS system. The building and the T-BAGS system are integrated and modeled as a three-dimensional series of masses and nonlinear springs. In those numerical analyses, the influence of the rigidity of the sandbags on the dynamic behaviors of the building is investigated. The results indicate that the response acceleration of the building, induced by the severe earthquake, could be considerably attenuated through the use of the T-BAGS base isolation and vibration control system. It is emphasized that the hysteretic shear behavior of the sandbags contributes significantly to vibration control.

T-BAGS是一种隔震和振动控制系统。它由两层堆积的土工布沙袋组成，里面装满了沙子。在上下沙袋之间夹一防滑片，以控制上下沙袋之间的滑移。上下沙袋之间的滑动作为基础隔离。此外，每个沙袋的滞回剪切变形对振动控制也有一定的作用。本研究首先通过室内试验研究了t - bag体系的静动力特性，包括1个沙袋的单剪试验和6组t - bag的振动台试验。然后，对振动台试验进行了动力数值分析。在此基础上，采用T-BAGS系统和不采用T-BAGS系统对一栋3层钢筋混凝土住宅楼进行了强烈地震作用下的动态三维分析。建筑和T-BAGS系统被整合并建模为一个三维质量和非线性弹簧系列。在这些数值分析中，研究了沙袋刚度对建筑物动力性能的影响。结果表明，采用T-BAGS隔震控制系统可以有效地降低建筑物在强震作用下的响应加速度。强调了沙袋的滞回剪切特性对振动控制的重要作用。

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引用次数: 0

Sustainable soil improvement using marine-derived biopolymers: strength and durability perspectives 利用海洋生物聚合物的可持续土壤改良：强度和耐久性的观点

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2026-04-01 Epub Date: 2026-01-24 DOI: 10.1016/j.sandf.2026.101730

Runshen Wang , Hadi Fatehi , Dominic E.L. Ong , Jimmy Yu , Ilhan Chang , Khosro Shabani

This study provides a comprehensive evaluation of marine biopolymers for sustainable soil stabilization. It offers critical insights for countries with abundant ocean resources to support the selection of suitable biopolymer for soil enhancement. The experimental program covers a wide range of mechanical and microstructural evaluations to support a broad understanding of biopolymer-treated soil behaviour. A range of marine biopolymers was tested with a specific focus on chitosan due to its distinct structure and bonding capability. The study focused on engineered kaolinite-sand mixtures, selected for their ability to represent complex and variable soil conditions commonly encountered in the field. Experimental variables such as biopolymer content, curing time, and soil composition were systematically controlled. Mechanical properties were assessed using UCS, and static and dynamic triaxial tests to determine shear strength and resilient modulus. Durability was assessed through five cycles of wetting and drying to replicate long-term environmental exposure. Results showed that biopolymer content and soil type significantly influenced strength development and water resistance. Chitosan achieved up to a tenfold increase in UCS, with substantial strength retention and low mass loss under cyclic conditions. Microstructural analysis using scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) provided insights into the chemical bonding and physical interactions at the soil–biopolymer interface. A mechanical model was proposed to explain these interactions. Overall, the study demonstrates the potential of marine biopolymers as effective, ecofriendly alternatives to traditional chemical stabilizers, offering a sustainable solution for geotechnical engineering applications.

本研究对海洋生物聚合物在土壤可持续稳定中的应用进行了综合评价。它为拥有丰富海洋资源的国家提供了重要的见解，以支持选择合适的生物聚合物用于土壤增强。实验项目涵盖了广泛的机械和微观结构评估，以支持对生物聚合物处理土壤行为的广泛理解。由于壳聚糖具有独特的结构和结合能力，因此对一系列海洋生物聚合物进行了测试。该研究的重点是工程高岭石-砂混合物，选择它们是因为它们能够代表在现场经常遇到的复杂和可变的土壤条件。实验变量如生物聚合物含量、固化时间和土壤成分被系统地控制。力学性能评估使用UCS，静态和动态三轴试验，以确定剪切强度和弹性模量。耐久性评估通过五个循环的湿润和干燥，以复制长期的环境暴露。结果表明，生物聚合物含量和土壤类型对强度发育和耐水性有显著影响。在循环条件下，壳聚糖的UCS增加了10倍，具有显著的强度保持和低质量损失。利用扫描电子显微镜（SEM）和傅里叶变换红外光谱（FTIR）进行微观结构分析，可以深入了解土壤-生物聚合物界面的化学结合和物理相互作用。提出了一个力学模型来解释这些相互作用。总的来说，该研究证明了海洋生物聚合物作为传统化学稳定剂的有效、环保替代品的潜力，为岩土工程应用提供了可持续的解决方案。

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引用次数: 0