Soils and Foundations最新文献_第6页

Experiment, modelling, and simulation of rate-dependent stress–strain behaviour of unbound geomaterials 实验，建模，和模拟速率依赖的应力应变行为的非束缚的地质材料

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-03 DOI: 10.1016/j.sandf.2025.101599

Fumio Tatsuoka , Hervé Di Benedetto

Various trends in rate-dependent stress–strain behaviour caused by the viscous properties of a wide variety of unbound geomaterials that were observed under drained triaxial compression, plane strain compression, direct shear, and one-dimensional compression (i.e., oedometer testing) are summarized referring to those of bound geomaterials and others. The following findings are shown. As the interparticle contact points become more stable and the stability of the particles against rotation increases, the viscous properties become closer to the traditional type, namely, Isotach, whose stress–strain behaviour is determined by the instantaneous irreversible strain rate and whose strength during monotonic loading (ML) at a constant strain rate increases with an increase in the strain rate. A couple of non-traditional (i.e., non-Isotach) types of properties were found with granular materials (GMs) that exhibit noticeable creep deformation, stress relaxation, and changes in stress upon changes in the strain rate. Unbound poorly graded sub-angular to angular GMs exhibit the so-called TESRA type of properties (also called the viscous evanescent type), for which the stress–strain behaviour during ML at a constant strain rate is essentially independent of the strain rate. Unbound poorly graded sub-round to round GMs display the so-called Positive and Negative (P&N) type of properties, for which the strength during ML at a constant strain rate decreases with an increase in the strain rate. The combined type displays intermediate behaviour combining the Isotach and TESRA types of properties. These types of viscous properties are quantitatively characterized by a couple of functions and parameters, and they were incorporated into the non-linear three-component (NTC) model. All the observed trends in rate-dependent stress–strain behaviour are well simulated by the NTC model.

在排水三轴压缩、平面应变压缩、直接剪切和一维压缩（即测径仪测试）下观察到的各种非粘结性岩土材料的粘性特性所引起的速率依赖的应力-应变行为的各种趋势，总结了粘结性岩土材料和其他岩土材料的趋势。结果如下。随着颗粒间接触点的稳定和颗粒抗旋转稳定性的提高，黏性更接近于传统的等压型，即等压型，其应力-应变行为由瞬时不可逆应变速率决定，在恒定应变速率下单调加载（ML）时的强度随着应变速率的增加而增加。在颗粒材料（GMs）中发现了一些非传统（即非等压）类型的性能，它们表现出明显的蠕变、应力松弛和应变速率变化时应力的变化。未结合的差梯度亚角到角GMs表现出所谓的TESRA类型性质（也称为粘性消失类型），其中恒定应变速率下ML期间的应力-应变行为基本上与应变速率无关。未结合的分级差的次圆到圆gm表现出所谓的Positive and Negative （P&；N）型性能，在恒定应变速率下，ML期间的强度随着应变速率的增加而降低。组合类型显示结合了Isotach和TESRA属性类型的中间行为。这些类型的粘性特性通过几个函数和参数进行定量表征，并将其纳入非线性三分量（NTC）模型。NTC模型很好地模拟了所有观察到的速率相关应力-应变行为趋势。

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引用次数: 0

Serviceability performance of piled raft foundations under vertical loads in clayey and sandy soils 粘性和砂质土中桩筏基础在竖向荷载作用下的使用性能

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-07-02 DOI: 10.1016/j.sandf.2025.101650

Der-Wen Chang , Shih-Hao Cheng , Wei-Cheng Zheng , Chan-Yen Tseng , Louis Ge

This study investigated the serviceability performance of piled raft foundations (or combined pile-raft foundations, CPRF) in various soils using three-dimensional (3D) finite element analysis. The piled raft foundation was assumed to be embedded respectively in homogeneous clayey soils and sandy soils under vertical loading. The displacements and reactions of the piles were carefully observed. In comparing the influences of soil stiffness, raft width, pile-to-pile spacing distance, and pile length, it was found that the embedment depth of the foundation could significantly affect the serviceability of the piles. For embedment depths ranging from 0 m to 12 m, the pile loads can be reduced by approximately 40 % to 60 % of the foundation load, depending on the number of piles involved. The displacements of piled raft foundations in clays decrease with increased embedment depth. However, the effects of embedment depth on foundation displacements are smaller in sands. Furthermore, the load ratio of the piles and the displacement ratio of the CPRF were calculated to demonstrate their dependence on the slenderness ratio of the piles and the number of piles. Both ratios aligned with the guidelines the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE) proposed for CPRF systems. Notably, attention is drawn to the depth of raft embedment, as it significantly influences pile responses.

本文采用三维有限元分析方法，研究了桩筏基础（或桩筏组合基础，CPRF）在不同土体中的使用性能。假定桩筏基础在竖向荷载作用下分别埋置于均质粘土和砂质土中。仔细观察了桩的位移和反力。通过对比土体刚度、筏板宽度、桩间距、桩长等因素的影响，发现基础埋深对桩的使用性能有显著影响。对于0米至12米的埋深，桩荷载可减少约40%至60%的基础荷载，具体取决于所涉及的桩数。土体中桩筏基础的位移随埋深的增加而减小。而在砂土中，埋深对地基位移的影响较小。计算了桩的荷载比和CPRF的位移比，证明了它们与桩长细比和桩数的关系。这两个比率都符合国际土力学与岩土工程学会（ISSMGE）为CPRF系统提出的指导方针。值得注意的是，筏板嵌入的深度引起了人们的注意，因为它对桩的响应有很大的影响。

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引用次数: 0

An approach for predicting earthquake-induced permanent displacements of embedded cantilever walls in soils with cohesion 含黏聚土中预埋悬臂墙地震永久位移预测方法

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-06-30 DOI: 10.1016/j.sandf.2025.101649

Luigi Pugliese, Antonello Troncone, Andrea Parise, Enrico Conte

Prediction of the earthquake-induced permanent displacements of retaining structures is a key step in the context of a performance-based design approach. For retaining walls with shallow foundations, this issue is usually dealt with using the well-known Newmark sliding block method. However, several studies have shown that this method is unsuitable to provide a trustworthy prediction of the permanent displacements undergone by the embedded cantilever retaining walls under seismic loading. To overcome this drawback, a new method of practical interest is proposed in the present study for a prediction of the earthquake-induced permanent displacement of these structures. In such a method, the wall movements are evaluated solving a simple equation of motion whenever the ground acceleration exceeds a critical value. This latter value is updated during the seismic event by calculating the forces acting on the wall by means of a closed form solution recently derived by the authors. The method is simple to use and requires few conventional parameters as input data. These features make it suitable for current applications. To assess the predictive capability of the present method, comparisons with the results of a centrifuge test documented in the literature and with those of a large number of ideal case studies solved using a finite element code, are presented. The effectiveness of some measures to reduce the wall displacements is also discussed.

在基于性能的设计方法中，地震引起的挡土结构永久位移的预测是关键的一步。对于基础较浅的挡土墙，通常采用著名的纽马克滑块法进行处理。然而，一些研究表明，这种方法不适合为地震荷载作用下预埋悬臂挡土墙的永久位移提供可靠的预测。为了克服这一缺点，本研究提出了一种实用的新方法来预测这些结构的地震引起的永久位移。在这种方法中，当地面加速度超过一个临界值时，墙体的运动是通过求解一个简单的运动方程来评估的。后一个值在地震事件期间通过计算作用在墙壁上的力，通过作者最近导出的封闭形式解来更新。该方法使用简单，需要的常规参数很少。这些特性使其适合当前的应用。为了评估本方法的预测能力，与文献中记录的离心机测试结果以及使用有限元代码解决的大量理想案例研究的结果进行了比较。讨论了减小墙体位移的一些措施的有效性。

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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 : 2025-06-26 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

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 : 2025-06-26 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

Experimental investigations and sustainability assessments of ground improvement studies of expansive soils 膨胀土地基改良试验研究及可持续性评价

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-06-26 DOI: 10.1016/j.sandf.2025.101637

Anand J. Puppala , Nripojyoti Biswas , Md Ashrafuzzaman Khan , Surya S.C. Congress

Expanding and maintaining transportation network assets on shrink-swell soils is a major problem for civil infrastructure owners and agencies across the world. Particularly, lightweight structures such as pavements experience distress due to differential heaving, cracking, shoulder dropping, and others. They can be primarily attributed to non-uniform moisture cycles, which severely impact both the short- and long-term performance of the structures. Among the available ground improvement techniques, both traditional and non-traditional methods are being effectively used to improve soil engineering properties and reduce distress during the service life period of the infrastructure asset. Novel chemical treatment methods and innovative geosynthetics have been employed to mitigate the distresses caused by shrink/swell movements from underlying expansive soils. The research team has studied applications of co-additives such as Geo-polymers and silica fines for stabilizing sulfate-rich expansive subsoils. An overview of stabilization studies using chemical additives, along with comprehensive sustainability analyses of these methods, were discussed in this paper. In addition, case studies on the application of geosynthetic products, including geocells and wicking geotextiles, for improvements of pavement performance built over expansive soils, are provided. Overall, the application of these new ground improvement techniques will be of immense help to infrastructure and transportation sectors and agencies as their usage would promote sustainable benefits with a higher return on investment.

在收缩膨胀土上扩展和维护交通网络资产是世界各地民用基础设施所有者和机构面临的主要问题。特别是，轻质结构，如路面，由于不同的起伏，开裂，肩下垂，和其他的痛苦。它们主要归因于不均匀的水分循环，这严重影响了结构的短期和长期性能。在现有的地基改善技术中，传统和非传统的方法都被有效地用于改善基础设施资产使用寿命期间的土壤工程特性和减少困扰。采用了新的化学处理方法和创新的土工合成材料来减轻下伏膨胀土的收缩/膨胀运动所造成的痛苦。研究小组研究了共添加剂的应用，如土工聚合物和二氧化硅粉，以稳定富含硫酸盐的膨胀底土。本文概述了化学添加剂稳定研究的概况，以及这些方法的综合可持续性分析。此外，还提供了应用土工合成产品的案例研究，包括土工细胞和吸芯土工织物，以改善在膨胀土壤上建造的路面性能。总的来说，这些新的地面改善技术的应用将对基础设施和运输部门和机构有巨大的帮助，因为它们的使用将促进可持续的利益，并带来更高的投资回报。

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引用次数: 0

Role of mineralogy on the undrained monotonic simple shear response of compacted filtered copper tailings 矿物学对压实过滤铜尾矿不排水单调单剪响应的影响

IF 3.3 2区工程技术 Q2 ENGINEERING, GEOLOGICAL

Soils and Foundations

Pub Date : 2025-06-25 DOI: 10.1016/j.sandf.2025.101636

Rodrigo Zorzal Velten , Carina Ulsen , João Paulo Rodrigues da Costa , Carlos Alex Alves Lima , Maiki Mafessoli , João Vítor de Azambuja Carvalho , Nilo Cesar Consoli

Tailings are anthropic materials whose behavior can be greatly affected by the mineralogy of their particles and the fabric formed. This paper focuses on the effects of tailings composition under plane strain conditions. For this, two copper tailings from distinct mines are studied. The tailings present a similar particle grading and morphology, so the main difference between them is restricted to mineralogy. Three compaction degrees and four effective confining pressure values (ranging from 50 to 400 kPa) were adopted. For the first time, the results of copper tailings under plane strain conditions are presented in the light of critical state soil mechanics due to the use of a simple shear apparatus equipped with backpressure and known horizontal stresses. The results revealed the influence of mineralogy on the critical state parameter M and the shape of the v – log p′ critical state lines. This highlights the importance of acknowledging mineralogy influence for properly designing tailings storage facilities.

尾矿是一种人为物质，其行为受其颗粒的矿物学特征和所形成的织物的影响很大。研究了平面应变条件下尾砂成分对尾砂的影响。为此，对两个不同矿山的铜尾矿进行了研究。两种尾矿的颗粒级配和形态相似，主要区别在于矿物学。采用3种压实度和4种有效围压值（50 ~ 400kpa）。利用具有背压和已知水平应力的简易剪切装置，首次从临界状态土力学角度给出了平面应变条件下铜尾砂的剪切结果。结果揭示了矿物学对临界状态参数M和v - log p '临界状态线形状的影响。这突出了认识矿物学影响对合理设计尾矿储存设施的重要性。

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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 : 2025-06-20 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 : 2025-06-20 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 : 2025-06-18 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