Soils and Foundations最新文献_第6页

Liquefaction response of reclaimed soils from effective stress analysis 基于有效应力分析的复垦土液化响应

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.2025.101677

Riwaj Dhakal, Misko Cubrinovski

One-dimensional (1D) dynamic effective stress site response analysis (ESA) is performed for profiles at the port of Wellington, New Zealand (CentrePort), which contains reclamation fills comprised of gravel-sand-silt (G-S-S) mixtures and hydraulic fills. The first phase of the study realistically simulates three recent earthquake case histories while considering modelling uncertainties by using the PM4Sand and the Stress-Density constitutive models. The results illustrate possible mechanisms explaining the severity of liquefaction manifestation and soil ejecta characteristics observed in G-S-S fills through careful engineering interpretation of the response. Challenges for 1D ESA to explain complex manifestation patterns affected by two-dimensional variability in fill composition and response characteristics are illustrated for the hydraulic fills. In the second phase of analyses, ESA-based response measures are proposed to quantify the severity of the liquefaction response for a range of input seismic demands. The response characteristics show very small scatter despite using a range of different input ground motions and two soil constitutive models. Results illustrate the capability of ESA to capture details of the liquefaction response such as the similar threshold seismic intensity for liquefaction triggering of the loosely deposited fills, different maximum response of the sites reflecting the differences in the thicknesses of the fills, and the evolution of the response from triggering to maximum reflecting differences in depositional characteristics.

对新西兰惠灵顿港（CentrePort）的剖面进行了一维动态有效应力响应分析（ESA），该剖面包含由砾石-沙子-淤泥（G-S-S）混合物和水力填充物组成的填海填充物。研究的第一阶段在考虑PM4Sand和应力-密度本构模型建模不确定性的情况下，实际模拟了最近三次地震的历史。研究结果通过对G-S-S填充物响应的细致工程解释，阐明了解释液化表现的严重程度和土壤喷射特征的可能机制。对于水力充填体，1D ESA在解释受充填体组成和响应特性二维变化影响的复杂表现模式方面面临挑战。在分析的第二阶段，提出了基于esa的响应措施，以量化一系列输入地震需求下液化响应的严重程度。在不同的输入地震动范围和两种土本构模型下，响应特性的离散性很小。结果表明，ESA能够捕捉液化响应的细节，如松散沉积填筑体液化触发的阈值地震烈度相似，反映填筑体厚度差异的不同地点的最大响应，以及反映沉积特征差异的响应从触发到最大的演变过程。

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引用次数: 0

Seismic performance of an existing anchored quay wall in the Ravenna port (Italy) 拉文纳港（意大利）现有锚碇码头墙的抗震性能

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.2025.101676

Pierluigi Alesiani , Paolo Ruggeri , Viviene M.E. Fruzzetti , Giuseppe Scarpelli

Evaluating the seismic performance of retaining walls is a significant engineering challenge due to non-linear soil-structure interaction, site response effects and ground motion properties. State of the art methods, based on non-linear dynamic analysis, are nowadays able to give reliable results when the numerical modeling is carried out with careful evaluation of seismic signals and appropriate choice of constitutive relationship for soils. However, a similar analysis is mostly restricted to relevant infrastructures. For large part of the practical situations, the simplified seismic analysis still represents the most used tool for design and verification. The new generation of Eurocode in Europe has introduced some innovations on the use of simplified seismic analyses making them more rationale and site-specific. In this paper, a case study involving the seismic evaluation of an existing anchored sheet-pile quay wall in the Ravenna port is presented. A well-known geotechnical setting and the data from an extensive field and laboratory investigation available for the area, allowed to perform both simplified and non-linear dynamic seismic analyses. The simplified seismic analysis according to the pseudo-static method outlined in the new draft of Eurocode 8 (FprEN1998:2024 TC250 – part 1 and 5), has been carried out and compared with the seismic performance of the quay wall evaluated through a 2D FEM non-linear dynamic analysis. Also, the seismic displacements of the quay wall from 2D FEM non-linear dynamic analysis were compared with recently proposed Newmark-type simplified methods. Relevant aspects of the presented case study are the very deep location of the bedrock, which required a separate model for site response analysis and 2D FEM non-linear dynamic analysis of the structures and the significant length of the wall embedment, due to poor geotechnical properties of the ground, which resulted in a pronounced spatial variation with depth of the ground motion.

由于非线性土-结构相互作用、场地反应效应和地震动特性，评估挡土墙的抗震性能是一项重大的工程挑战。目前，基于非线性动力分析的方法，在对地震信号进行仔细评估和适当选择土的本构关系的情况下进行数值模拟，能够给出可靠的结果。然而，类似的分析主要局限于相关的基础设施。在大部分实际情况下，简化地震分析仍然是最常用的设计和验证工具。欧洲新一代的欧洲规范在简化地震分析的使用上引入了一些创新，使它们更加合理和具体。本文介绍了拉文纳港现有锚固板桩码头墙的地震评价实例。众所周知，该地区的地质技术背景和广泛的现场和实验室调查数据，允许进行简化和非线性动态地震分析。根据欧洲规范8新草案（FprEN1998:2024 TC250 - part 1和part 5）中概述的拟静力法进行了简化的地震分析，并与通过二维有限元非线性动力分析评估的码头墙抗震性能进行了比较。同时，将二维有限元非线性动力分析得到的码头墙体地震位移与近期提出的newmark型简化方法进行了比较。所提出的案例研究的相关方面是基岩的非常深的位置，这需要一个单独的模型进行现场响应分析和二维有限元非线性动力分析的结构和墙体嵌入的显著长度，由于地面的岩土性能差，导致地面运动的深度明显的空间变化。

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引用次数: 0

Experimental and numerical simulation for shear failure mechanism of silty clay–structure interface 粉质粘土-结构界面剪切破坏机理的实验与数值模拟

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.2025.101683

Boxin Wang , Zihao Wang , Wen Zhang , Jingjing Pan , Jiaqi Liu , Qing Wang

The shear phenomenon between soil and foundation structure is common in foundation engineering. The change in the water content of stratum affects the shear behavior of soil and structure inevitably, especially in the region of cohesive soil with complex hydro-physical properties. In this paper, the silty clay in the Songnen Plain was used as a case study to reveal the shear failure mechanism of silty clay–structure interface under different water contents from multiple scales. First, the macroscopic mechanical characteristics were investigated by direct shear test and particle-image-velocimetry technology. To further explore the mesoscopic evolution law, this study proposed a novel FDM-DMDEM (Finite Difference Method–Determining Meso-parameter Discrete Element Method). This method enables direct calculation and assignment of meso-parameters required for the numerical model based on unsaturated soil theory, completely circumventing the laborious and subjective inverse calibration process inherent in conventional DEM. In this study, a 3D numerical model was established by using this coupling method and a parametric analysis was carried out. The results demonstrated that the meso-structure failure of silty clay within a certain range from the interface produced plastic deformation to form shear bands. Failure has two forms, namely, shear failure inside the shear band and shear failure outside the shear band. The increase in water content weakened the bonding force between particles, so that developing shear stress outside the shear band was difficult, resulting in typical shear failure inside the shear band. These findings could provide certain design references for the construction of foundation engineering in the Songnen Plain area.

土与基础结构之间的剪切现象是基础工程中常见的现象。地层含水率的变化不可避免地影响着土体和结构的剪切性能，特别是在水物性复杂的粘性土区域。本文以松嫩平原粉质粘土为例，从多尺度上揭示了不同含水量下粉质粘土-结构界面剪切破坏机理。首先，采用直剪试验和颗粒图像测速技术对其宏观力学特性进行了研究。为了进一步探索细观演化规律，本研究提出了一种新的FDM-DMDEM（有限差分法-确定细观参数离散元法）。该方法可以直接计算和分配基于非饱和土理论的数值模型所需的细观参数，完全避免了传统DEM固有的费力和主观的反校准过程。本文采用该耦合方法建立了三维数值模型，并进行了参数化分析。结果表明：粉质粘土在一定范围内的细观结构破坏，从界面开始产生塑性变形，形成剪切带；破坏有剪切带内剪切破坏和剪切带外剪切破坏两种形式。含水量的增加削弱了颗粒间的结合力，使剪切带外产生剪切应力变得困难，导致剪切带内出现典型的剪切破坏。研究结果可为松嫩平原地区基础工程的施工提供一定的设计参考。

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引用次数: 0

Suffusion behavior under fluctuated hydraulic gradient conditions focusing on amount and size of soil particles contained in drainage 波动水力梯度条件下的渗流行为主要关注排水中所含土壤颗粒的数量和大小

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-08-01 Epub Date: 2025-07-03 DOI: 10.1016/j.sandf.2025.101600

Taichi Ishimaru , Motoyuki Suzuki , Asahi Komori

Suffusion is the detachment and migration of fine particles through voids connected by the matrices of coarse particles. Although water storage structures are known to be affected by fluctuations in seepage flow, due to fluctuations in the water storage levels brought about by rainfall and agricultural activities, the suffusion behavior when the hydraulic gradient is fluctuated is unclear. In this study, one-dimensional downward water-passing experiments with suffusion were performed using a cylindrical column device, and the changes in the amounts of the discharged water and soil particles, as well as the turbidity of the drainage over time, were examined. The behavior of suffusion was investigated from two viewpoints: the quantitative changes in the amount of discharged drainage and the amount of discharged soil particles due to the progress of suffusion, and the qualitative changes in the particle size composition of the discharged soil particles. A unique feature of this study was the tracing of the changes in the particle size composition of the discharged soil particles from the relationship between the turbidity and the concentration of drainage during suffusion. As a result, it was found that not only the amount of soil particles discharged by suffusion, but also the particle size composition of the discharged soil particles changed under both constant and fluctuated hydraulic gradient conditions.

渗透是细颗粒通过由粗颗粒基质连接的空隙脱离和迁移的过程。虽然已知蓄水结构会受到渗流波动的影响，但由于降雨和农业活动带来的蓄水水位波动，水力梯度波动时的渗流行为尚不清楚。在本研究中，采用圆柱柱装置进行了一维向下扩散进水实验，考察了排放的水和土壤颗粒量以及排水浊度随时间的变化。从渗流过程中排水量和排入土壤颗粒量的量变和排入土壤颗粒粒径组成的质变两个角度研究了渗流行为。本研究的一个独特之处在于，通过浸渍过程中浊度与排水浓度的关系，追踪了排放土壤颗粒粒径组成的变化。结果发现，在恒定和波动水力梯度条件下，不仅渗透排出的土粒量发生了变化，而且排放土粒的粒径组成也发生了变化。

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引用次数: 0

Seepage pressure distribution of gas jet flow in loess 黄土中气体射流渗流压力分布

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-08-01 Epub Date: 2025-06-26 DOI: 10.1016/j.sandf.2025.101648

Changhui Gao , Songyu Liu , Guangyin Du , Mei Bai , Yankai Wu , Runmin Hao

This study aims to investigate the permeation mechanisms and pressure distribution of gas jets in collapsible loess during pneumatic-vibratory probe compaction (PVPC). Indoor model tests were performed to analyze the behavior of continuous gas jet injection, and a seepage pressure distribution model was developed to characterize gas flow in unsaturated loess. The results show that pulsating gas jets disrupt the soil structure near the nozzle, enabling gas penetration driven by internal pressure differentials and leading to the gradual formation of continuous fractures. Gas pressure measurements at the opposite end of the soil layer indicate an initial pressure rise that stabilizes over time, with thinner soil layers showing more pronounced responses. The proposed model effectively captures the dynamic behavior of gas flow, illustrating a rapid decline in seepage pressure over time and a slow increase in seepage distance. These findings enhance the understanding of gas jet permeation and provide practical guidance for optimizing PVPC parameters, further advancing its application in loess foundation improvement within geotechnical engineering.

研究了湿陷性黄土在气振探测压实过程中气体射流的渗透机理和压力分布。通过室内模型试验分析了气体连续喷射的特性，建立了非饱和黄土中气体流动的渗流压力分布模型。结果表明：脉动气体射流破坏了喷口附近的土体结构，使气体在内部压差的驱动下穿透，逐渐形成连续裂缝；在土层另一端的气体压力测量表明，随着时间的推移，初始压力上升趋于稳定，土层越薄，反应越明显。该模型有效地捕捉了气体流动的动态特性，显示了渗流压力随时间的快速下降和渗流距离的缓慢增加。这些研究结果增强了对气体射流渗透的认识，为优化PVPC参数提供了实践指导，进一步推进了其在岩土工程中黄土地基加固中的应用。

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引用次数: 0

Sandpile experiments and statistical analysis for slope failure, failure shape, and frequency distribution 砂堆试验及边坡破坏的统计分析，破坏形态及频率分布

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-08-01 Epub Date: 2025-07-31 DOI: 10.1016/j.sandf.2025.101665

W.S.G. Fernando , Yota Togashi , Teppei Kato , Masahiko Osada

Natural slopes, which occur without human intervention, are susceptible to failure triggered by events such as earthquakes and heavy rainfall. The characteristics of these failures, including the shape of the slip surface and the magnitude of collapse, vary significantly due to factors like the direction of seismic motion, ground heterogeneity, and unsteady rainfall infiltration. Despite numerous experimental studies, the probabilistic nature of slope failure phenomena remains insufficiently understood. This study employs experimental and statistical analysis using the sandpile model to elucidate slope failures and their magnitudes. The sandpile model involves gradually adding sand to a pile and repeatedly observing its collapse. Experiments were conducted using silica sand No. 8 (fine sand) on base plates with diameters ranging from 5 cm to 12 cm. Shape variations were captured using a depth camera. The results indicate significant geometric changes predominantly at the apex of the sandpile, where the initial breach of stability occurs. The metastable slope angle at the apex of the sandpile induces hysteresis behavior in slope failure. The frequency of occurrence and failure mass deviates from a normal distribution, with smaller magnitudes occurring more frequently and a sharp decrease in frequency for larger magnitudes. This pattern mirrors the frequency-magnitude relationship observed in earthquakes, with the study’s results aligning with the Gutenberg-Richter law, confirming the hypothesis. The b-value obtained from this study falls within the range of frequency-size landslide statistics available in the literature.

自然斜坡是在没有人为干预的情况下形成的，容易受到地震和强降雨等事件的破坏。由于地震运动方向、地面非均质性和降雨入渗不稳定等因素的影响，这些破坏的特征（包括滑面形状和崩塌幅度）变化很大。尽管进行了大量的试验研究，但对边坡破坏现象的概率性质仍知之甚少。本研究采用砂桩模型对边坡破坏及其震级进行了实验分析和统计分析。砂堆模型涉及到逐渐向桩上加砂，并反复观察其倒塌。实验采用8号硅砂（细砂）在直径为5 cm ~ 12 cm的底板上进行。形状变化是用深度相机捕捉到的。结果表明，砂堆的几何变化主要发生在砂堆的顶端，这是最初破坏稳定的地方。砂桩顶端的亚稳坡角导致边坡失稳的迟滞行为。发生频率和破坏质量偏离正态分布，较小的震级发生频率较高，较大的震级发生频率急剧下降。这种模式反映了在地震中观察到的频率-震级关系，研究结果与古腾堡-里希特定律一致，证实了这一假设。本研究获得的b值在文献中可用的滑坡频率大小统计范围内。

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引用次数: 0

Investigation of acting load and mechanical characteristics of shield tunnel lining in upper-soft and lower-hard stratum 上软下硬地层盾构隧道衬砌作用荷载及力学特性研究

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-08-01 Epub Date: 2025-06-26 DOI: 10.1016/j.sandf.2025.101647

Tao Zhang , Yufeng Shi , Shuying Wang , Menghao Hu , Sijin He

When shield tunnels traverse the upper-soft and lower-hard stratum, the pronounced geological differences lead to uneven stress distribution on the segmental lining, thereby intensifying both construction challenges and safety risks. Investigating the loading conditions and mechanical characteristics of tunnel linings in such strata is imperative. Therefore, field measurements were conducted at two shield tunnel construction sites along Nanchang Metro Line 1, specifically within a silty clay-gravel layer and a homogeneous sand layer. The acting load and internal forces of the segmental lining were monitored over an extended period. By analyzing the monitoring data, the variation patterns of the loads acting on the segmental lining in the upper-soft and lower-hard stratum during the construction stage were summarized. Furthermore, a comparative analysis was carried out between the measured loading conditions and the theoretical analytical solutions. Subsequently, a refined numerical simulation incorporating bolt joints and bolt preload on the segment was performed to further explore the mechanical behavior of the segmental lining, with a comparison to the measured internal force data. The results indicate that synchronous grouting at the shield tail significantly affects the earth pressure in the upper soft soil layer, with the maximum earth pressure induced by synchronous grouting being approximately 1.9 times the final stable value. The vertical earth pressure in the upper part of the segmental lining exhibits a characteristic pattern of being “large in the middle and small at both ends”, with the measured maximum value after stabilization corresponding to approximately 72% of the theoretical value predicted by Terzaghi’s theory. Notably, a sudden change in lateral earth pressure is observed at the stratum interface. The bending moment and axial force at the invert of the tunnel segment are comparatively smaller than those at the vault. Additionally, the development of internal forces within the segment is fairly constrained in the lower hard stratum.

盾构隧道穿越上软下硬地层时，地质差异明显，导致管片衬砌应力分布不均匀，加剧了施工挑战和安全风险。研究此类地层中隧道衬砌的受力条件和力学特性是十分必要的。因此，在南昌地铁1号线的两个盾构隧道施工现场进行了现场测量，特别是在粉质粘土-砾石层和均匀砂层中。长时间监测了分段衬砌的作用荷载和内力。通过对监测数据的分析，总结了上软下硬地层中管片衬砌在施工阶段荷载的变化规律。并将实测载荷条件与理论解析解进行了对比分析。随后，进行了包含螺栓连接和螺栓预紧力的精细化数值模拟，以进一步探索管片衬砌的力学行为，并与测量的内力数据进行了比较。结果表明：盾构尾端同步注浆对上部软土层土压力影响显著，同步注浆引起的最大土压力约为最终稳定值的1.9倍；管片衬砌上部竖向土压力呈现“中间大、两端小”的特征，稳定后的实测最大值约为Terzaghi理论预测的理论值的72%。值得注意的是，在地层界面处观察到侧向土压力的突然变化。隧道段仰拱处的弯矩和轴力相对小于拱顶处。此外，在较低的硬地层中，段内内力的发展受到相当大的限制。

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引用次数: 0

Effect of fines contents on uplift behavior of underground structures in liquefiable ground 细粒含量对液化地基地下结构上拔性能的影响

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-08-01 Epub Date: 2025-06-20 DOI: 10.1016/j.sandf.2025.101623

Fernaldy Sebastian Santoso , Kenji Watanabe

Research on liquefaction began decades ago, with clean sand being the main material . Recently, as it has been proven that fines-containing materials are also suspected to be liquefied, additional studies, mainly elementary tests, have been conducted. However, few liquefaction model experiments have been conducted in which the fines content is varied. This is because it is difficult to completely saturate a model ground with fines and conduct highly reproducible model experiments. In the present study, therefore, a modified vacuum container sand box and large-size vacuum saturation method were adopted to perfectly saturate model grounds with different non-plastic fines contents. A pipe model was placed in the ground to investigate the uplift behavior of an underground structure induced by liquefaction.

The experiments revealed that a ground with a higher fines content induced a lower total uplift displacement in the pipe model than grounds with a lower or no fines content. Interestingly, these results differ from the liquefaction properties of the fines-mixed sand observed in previous elementary tests. The discrepancy is probably due to the effects of the strength recovery of the ground, low void ratio, low permeability, and high viscous resistance of such a soil with fines.

液化的研究开始于几十年前，以干净的沙子为主要材料。最近，由于已证明含有细颗粒的材料也被怀疑是液化的，因此进行了更多的研究，主要是初级试验。然而，很少进行细粒含量变化的液化模型实验。这是因为很难用细粉使模型地面完全饱和并进行高重复性的模型实验。因此，本研究采用改进的真空容器砂箱和大尺寸真空饱和法对不同非塑性细粒含量的模型地基进行了完全饱和。为了研究液化引起地下结构的隆升行为，在地下放置了一个管道模型。试验结果表明，细粒含量较高的地基比细粒含量较低或不含细粒的地基在管道模型中引起的总上拔位移较小。有趣的是，这些结果不同于在以前的初级试验中观察到的细混合砂的液化特性。这种差异可能是由于地基的强度恢复、低空隙比、低渗透性和高粘阻等因素的影响。

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引用次数: 0

Deformation, resistance characteristics, and scale effects of rockfall protection soil embankments under static loading 静力荷载作用下防落石土路堤变形、阻力特性及尺度效应

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-08-01 Epub Date: 2025-06-20 DOI: 10.1016/j.sandf.2025.101634

Yoshiyuki Oguri , Kenichi Maeda , Keisuke Kondo , Takuro Nakamura , Yuji Ushiwatari , Naoto Naito , Masato Komuro

Rockfall protection soil embankments are structures that can effectively reduce rockfall hazards along roads. They are economical and easy to construct and maintain by using locally available soil. However, a performance design method for rockfall protection soil embankments has not yet been established, and is the goal of this study. In the present study, static loading tests were conducted using two different weight shapes to clarify the influence of the weight shape on the deformation behavior of soil embankments. Based on these tests, the punching shear failure mechanism of the soil embankments was investigated. The influence of the model scale (the scale effect) on the deformation failure behavior of the soil embankments was clarified through static loading tests on reduced models at three different scales. From these model experiments, the surface deformation, internal deformation, and load–penetration relationships of the soil embankments were summarized. The results indicated that the spherical weight damaged a wider area than the polyhedral weight, and the maximum and ultimate loads exhibited a constant relationship with the deformation of the soil embankment extension between the model scales.

防落石土路堤是一种能有效减少道路沿线落石灾害的结构。它们经济且易于使用当地可用的土壤来建造和维护。然而，目前还没有建立起防落土路堤的性能设计方法，这也是本研究的目标。本研究采用两种不同重量形状进行静载试验，以阐明重量形状对土路堤变形行为的影响。在此基础上，对土路堤冲剪破坏机理进行了研究。通过对三种不同尺度的模型进行静载试验，阐明了模型尺度（尺度效应）对土路堤变形破坏行为的影响。通过这些模型试验，总结了土路堤的表面变形、内部变形和荷载-侵彻关系。结果表明，球形荷载比多面体荷载的破坏面积更大，最大和极限荷载与模型尺度之间的土路堤延伸变形呈恒定关系。

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引用次数: 0

Strengthening the subgrade clay soil using nano chemical stabilisation 利用纳米化学稳定技术加固路基粘土

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-08-01 Epub Date: 2025-06-18 DOI: 10.1016/j.sandf.2025.101638

Kodi Rangaswamy, Regi P. Mohan

Nowadays, non-traditional eco-friendly nanomaterial additives are widely utilized in the geotechnical stabilization of soft soils. The application of materials developed using nanotechnology in stabilizing soils effectively reduces or replaces the utility of cementation products like cement and lime, which leads to environmental pollution. This article evaluates the efficacy of organosilane nano-chemical additive with 1 % cement binder in improving the strength properties of soft soil used for road-based applications. A series of experimental tests were conducted to characterize the geotechnical properties of soft clay and nano-chemical-treated soft soils with 1 % cement binder, including soil gradation, consistency limits, compaction, unconfined compression, and California bearing ratio (CBR) strength, and microstructural and chemical analysis. A small dosage of 1 % cement was added to the parent clay to accelerate the cementitious reactions in soil treated with a nano-chemical additive. The dosage of nano-chemical additives used was varied from 0.03 to 0.05 % for the present study. The treated clayey soil is examined for the optimum dosage corresponding to the highest unconfined compression strength of soil samples cured up to 28 days. Test results show that the soft clay treated with organosilane-based nano-chemical at an optimum dosage of 0.045 % and 1 % cement binder has attained the maximum unconfined compression and CBR strengths. SEM and FTIR results postulate the microstructural and chemical interactions involved in supporting the mechanism of improvement in the strength of treated soils.

目前，非传统的环保纳米材料添加剂在软土的岩土稳定中得到了广泛的应用。利用纳米技术开发的材料在稳定土壤中的应用，有效地减少或取代了水泥和石灰等胶结产品的使用，从而导致环境污染。本文评价了有机硅烷纳米化学添加剂添加1%水泥粘结剂对改善道路用软土强度性能的效果。研究人员进行了一系列实验测试，以表征含有1%水泥粘合剂的软粘土和纳米化学处理软土的岩土力学特性，包括土壤级配、稠度极限、压实、无侧限压缩和加州承载比（CBR）强度，以及微观结构和化学分析。在母质粘土中加入少量1%的水泥，以加速纳米化学添加剂处理过的土壤的胶凝反应。在本研究中，纳米化学添加剂的用量为0.03% ~ 0.05%。对处理后的粘土进行了试验，以确定固化至28天的土样的最高无侧限抗压强度所对应的最佳用量。试验结果表明，有机硅基纳米化学剂在掺量为0.045%、水泥粘结剂掺量为1%的条件下处理软粘土获得了最大的无侧限抗压强度和CBR强度。SEM和FTIR结果假设微观结构和化学相互作用参与支持改善处理土壤强度的机制。

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引用次数: 0