Transportation Geotechnics最新文献

Field implementation of a rational Otta seal mix design for enhanced performance on low-volume roads

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-22 DOI: 10.1016/j.trgeo.2025.101577

Md Jibon , Bo Yang , Masrur Mahedi , Halil Ceylan , Sunghwan Kim

Low-volume roads connecting rural communities and agricultural fields face unique challenges due to heavy traffic and constrained budgets for maintenance and rehabilitation. The Otta seal surfacing technique utilizing bituminous material and graded aggregates to create a durable road surface has emerged as a promising solution. This study explores a rational mix design, a modified McLeod method, for Otta seal application considering local material properties, and compares it with existing design guidelines. The study involves constructing test sections following a rational design technique and conventional Overby recommended guidelines. The performance of the test sections was assessed by testing skid resistance, surface roughness, dust generation, and structural stiffness over a two-year period. The test section constructed following the modified McLeod method outperformed sections built per traditional Overby guidelines in terms of cost-effectiveness and overall performance. Specifically, the test section that was constructed using the modified McLeod method exhibited the lowest roughness, dust, and loose aggregate from the surface. Results from life cycle cost analysis (LCCA) highlight the economic benefits of the rational mix design technique, demonstrating the economic advantages of the rational mix design, showcasing lower construction and maintenance costs. By adapting the modified McLeod method to suit the local aggregate materials, engineers can achieve more appropriate and accurate application rates for both aggregates and binders, thereby optimizing the performance of the overall mixture. The study contributes practical insights for optimizing Otta-seal surfacing, emphasizing the significance of using local material properties and rational mix design for enhancing the longevity and cost-effectiveness of low-volume roads in Iowa.

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引用次数: 0

Utilizing Dielectric Constant and Electrical Conductivity to Estimate Cement Content in Stabilized Subgrade Soils

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-21 DOI: 10.1016/j.trgeo.2025.101573

Zack Hall , S. Sonny Kim

Cement stabilization is a standard method used to strengthen fine-grained soils that are locally available and prepare them for pavement construction. Flexible pavements over cement-stabilized soils commonly experience mild reflective cracking originating from the shrinkage cracks on top of the stabilized layer. The severity of this form of reflective cracking is correlated to inadequate soil–cement construction practices which include thin stabilized layers, low compaction, deviations in cement content from the mix design, and rapid moisture loss. Consequently, these construction issues can significantly reduce the flexible pavement strength and overall life cycle. In this study, a non-destructive quality assurance method using a ground penetrating radar (GPR) and percometer was developed to capture stabilized soil’s inconsistent cement content and hydration rates. A predictive model derived from laboratory testing was created based on the distinct hydration rates, dielectric constants, and electrical conductivities associated with different water and cement contents. Laboratory testing shows that GPR can detect these inconsistencies in cement-stabilized layers within the first seven days after construction through non-destructive testing.

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引用次数: 0

Monitoring and prediction of surface deformation along railways lines in karst areas using multi-source data − a case study of the Beijing-Guangzhou Railway in China

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-19 DOI: 10.1016/j.trgeo.2025.101564

Zhixing Deng , Yuanxingzi He , Yongwei Li , Linrong Xu , Yuanjie Xiao , Qian Su

The Karst collapse seriously affects the safe operation of railways. Identifying the instability target areas along the railway and capturing its deformation trend is one of the most effective methods for controlling this hazard. However, the traditional methods of monitoring and analyzing deformation along the railway line are too single, resulting in the inability to carry out comprehensive identification of deformation and advance prediction. Hence, a method using multi-source data is proposed to monitor and predict surface deformation along railway lines in karst areas. Taking the Guangzhou part of the Beijing-Guangzhou Railway in China as an example, the hazards and adjacent human engineering activities along the railway are monitored by using multi-source means of “Space-Air-Ground” at first. Secondly, taking the time-series deformation values as the data basis, the wavelet transform (WT) algorithm is used to reduce the noise of the time-series deformation in the three historical subgrade karst collapse points. Five classical machine learning (ML) models are used for the prediction analysis of the deformation, and the optimal ML model is utilized to advance prediction. The results show: 1) There are two settlement target areas along the railway, and the settlement range is expanding and the cumulative settlement increases year by year in 2021–2023, with the maximum cumulative settlement of −118.01 mm. 2) The characteristic points in Area A continue to sink from 2019 to 2023, with a maximum cumulative settlement of −108.01 mm. The characteristic points in Area B continue to sink from 2021 to June 2023 due to disturbance from adjacent projects. 3) The prediction effect of the WT-LSTM is optimal through prediction analysis, and the scale of future deformation prediction is about one year based on the results of the advance prediction. The research findings can provide key technical support for the identification and early prevention of settlement hazards along railways.

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引用次数: 0

Machine learning techniques for evaluation of permanent deformation responses from geogrid stabilized pavements

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-19 DOI: 10.1016/j.trgeo.2025.101568

Prajwol Tamrakar , Jayhyun Kwon , Mark H. Wayne

Permanent deformation reduction (a.k.a., rut resistance capacity) and stiffness improvement are two key features of geogrid stabilized pavements. Furthermore, geogrids also contribute to preserving the uniformity of the stiffness distribution over a wide area, proving the increased reliability provided by stabilization. In most common pavement design and evaluation methodologies, permanent deformation is an essential component for long-term pavement performance assessment. For example, the AASHTO (Association of State Highway Transportation Officials) R50 standard considers permanent deformation for the derivation of the traffic benefit ratio (TBR) or base course reduction (BCR) factor. Although full-scale accelerated pavement testing or in-service pavement testing is ideal for assessing permanent deformation responses, such testing may not be feasible to perform in a wide range of situations, including diverse subgrade types, climatic zones, and material types. An alternative is to use large-scale plate load testing for in-situ material characterization. Automated Plate Load Testing (APLT) is a field-based plate load testing system for applying dynamic loads and measuring permanent and resilient deformations. For this paper, APLTs were conducted to measure permanent deformations on several pavement sections consisting of different aggregate base course (ABC) thicknesses, ABC material types, multi-axial geogrids, and subgrade conditions. Several machine learning techniques, including Multiple Linear Regression Analysis (MLRA), Gene Expression Programming (GEP), Customized Non-linear Regression (CNR), Traditional Machine Learning (TML), and Artificial Neural Networks (ANN), were explored to develop prediction models for permanent deformation. Among the TML models, Extra Tree, XGBoost, and LightGBM demonstrated superior accuracy and robustness against overfitting. These models effectively captured the complex interactions between model parameters, making them suitable for evaluating geogrid-stabilized pavements.

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引用次数: 0

Effect of fault dislocation on the deformation and damage behavior of ballastless track structures in tunnels

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-19 DOI: 10.1016/j.trgeo.2025.101561

Xuhao Cui , Yapeng Liu , Xiuli Du , Hong Xiao , Hongbin Xu , Yanliang Du

This study focuses on the mechanical behavior of slab track structures within railway tunnels that traverse fault zones. By combining the concrete damaged plasticity (CDP) model with the finite element method, a coupled simulation model of the slab track-tunnel-surrounding rock system has been established. The analysis primarily centers on the effects of fault dislocation on the stress, deformation, and damage characteristics of both CRTS II and CRTS III slab tracks, with the former featuring longitudinally connected track slabs and the latter characterized by unit-type track slabs. The results demonstrate that under normal fault dislocation, track irregularity, structural damage, and the interlayer gap all increase as fault displacement grows. Owing to its relatively higher structural stiffness, the CRTS II slab track is more susceptible to stress concentration, thereby leading to more severe damage to the track slab and base plate, as well as larger interlayer gaps. Specifically, the maximum damage variable of the track slab in the CRTS II slab track is 16 times that of the CRTS III slab track, and its maximum interlayer gap is 1.3 times larger than that of CRTS III slab track. By contrast, the unit-type design of the CRTS III slab track endows it with better adaptability to foundation deformation and mitigates stress concentration. However, this design leads to more increased track irregularity. The maximum upward bending deflection of the rail on the hanging wall side of the fault in the CRTS III slab track is twice as large as that of the CRTS II slab track. Under reverse fault dislocation, compared to normal fault dislocation, the compressive effects reduce structural damage, yet the trends of deformation and interlayer contact remain consistent with the variation of fault displacement. This research offers valuable insights for the design and maintenance of high-speed railway tracks within tunnels that cross fault zones.

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引用次数: 0

Field data-based prediction of local scour depth around bridge piers using interpretable machine learning

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-18 DOI: 10.1016/j.trgeo.2025.101567

Taeyoon Kim , Azmayeen R. Shahriar , Woo-Dong Lee , Yongjin Choi , Siyoon Kwon , Mohammed A. Gabr.

Local pier scour is one of the leading causes of bridge failure worldwide. It occurs when flowing water generates shear stresses at the water–sediment interface, leading to the erosion of soil particles or mass around the pier foundation. In this study, an efficient and accurate machine learning approach is developed for predicting local scour depth around bridge piers. Initially, the field data from the US geological survey database were preprocessed and divided into training, validation, and test sets. The hyperparameters of the models were then adjusted using Bayesian optimization and 5-fold cross-validation. Among the three machine learning models considered in this study, the eXtreme gradient boosting (XGB) model achieved the highest accuracy, which was significantly higher than those realized by four local scour estimation equations utilized in the study. To improve the interpretability of machine learning as a black-box model, SHapley Additive exPlanations (SHAP) was used to interpret the predictions of the XGB model. Interpretable ML analysis indicated that

y / b_{n}

was the most influential factor, aligning with the focus on assessing the scour magnitude. In addition, the machine learning interpretation also indicates that the patterns captured by the XGB model are consistent with the theoretical understanding of factors affecting the local scour, thereby validating that the proposed model achieves reasonable predictions. Finally, the gap between laboratory and field data is explained, and a method to address such a gap is proposed considering accuracy and conservatism levels in the assessed scour atudes.

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引用次数: 0

Evaluation of the freeze-thaw performance of silane treated pavement subgrade soils 评估硅烷处理过的路面基层土壤的冻融性能

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-18 DOI: 10.1016/j.trgeo.2025.101571

Md Fyaz Sadiq , Mohammad Wasif Naqvi , Bora Cetin , Emmanuel Adeyanju , John Daniels , Michael Uduebor

Silane can be effective in limiting freeze–thaw impact on pavement systems as it creates water-repellent properties in the substrate and can limit the water ingression to subgrade soil. While primary frost heave stems from the phase change of pore water to ice, secondary frost heave is induced by continuous water flow from the vadose zone towards growing ice lenses. Consequently, limiting the influx of water from the vadose zone could be the most efficient approach to mitigate the detrimental effects of freeze–thaw cycles on subgrade soils. This study aims to minimize the freeze–thaw effects by treating subgrade soils with silanes. Two frost susceptible soils from Iowa (IA-PC and IA-KC) were sprayed with two different dosages (1.6 L/m² and 3.2 L/m²) of silanes, and spraying was employed at multiple depths within the specimens. One-dimensional frost heave tests were conducted, and frost heave potential was measured in terms of water intake, total frost heave, heave rate, and soil water content. The silane treatment resulted in a reduction in frost heave, ranging between 57 % and 80 %. The heave rate for the untreated IA-PC specimen was 4.3 mm/day, which decreased to 0.4 mm/day with a two-layer spray treatment using a silane concentration of 1.6 L/m². Increasing the number of silane-sprayed layers was more effective than increasing the silane concentration to limit water ingress and enhance the freeze–thaw resistance of the subgrade soil.

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引用次数: 0

Experimental and numerical studies on geosynthetic encased stone columns in saturated and unsaturated soils

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-17 DOI: 10.1016/j.trgeo.2025.101566

Shakeel Abid Mohammed , Deendayal Rathod , Sai K. Vanapalli

Geosynthetic encased stone columns are conventionally designed based on the principles of saturated soil mechanics ignoring in-situ unsaturated conditions. Such an approach results in over conservative and, in certain scenarios, unrealistic designs. A more rigorous approach is required for design of stone columns considering the influence of saturated and unsaturated soil conditions taking account of area replacement ratio of stone columns and the stiffness of geosynthetic encasement considering site specific conditions. However, such an approach is presently not available in the literature. For this reason, in this study, 42 physical model tests were conducted that suggest an increase in carrying capacity of stone columns by 14 times understand unsaturated conditions in comparison to saturated conditions for the soil tested. A non-linear increase in load-bearing capacity was observed in boundary effect and primary transition zones while a decline was noted in secondary transition and residual zones due to reduced matric suction contribution. Additionally, comparisons were drawn using 3D finite element analyses, which were extended to prototype-scale studies to understand variations in confining pressure and soil deformation around stone columns in unsaturated conditions. The numerical results validated the experimental results, showing a 50% reduction in settlements due to the contribution of matric suction. Finally, a simple framework is proposed for predicting the load-carrying capacity of encased stone columns extending the mechanics of saturated and unsaturated soils. The rational design methodology summarized in this study for extending it into geotechnical engineering practice can contribute to potential cost savings by optimizing geosynthetic stiffness, stone column diameter, and area replacement ratio.

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引用次数: 0

Mechanistic-empirical method of pavement design extending unsaturated soil mechanics

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-17 DOI: 10.1016/j.trgeo.2025.101569

Kenneth O. Omenogor , Won Taek Oh , Sai K. Vanapalli

Pavement system that typically constitutes of different soil and material layers is located within the vadose zone that is above the groundwater table, which is in an unsaturated condition. Due to this reason, suction is a crucial stress state variable for interpreting the behavior of pavements in the vadose zone. The Mechanistic-Empirical Pavement Design Guide (MEPDG) serves as a comprehensive design tool that accounts for both the resilient response and environmental influences on pavement material properties. In this study, a series of California Bearing Ratio (CBR) tests were conducted on both saturated and unsaturated compacted soils that are commonly used as pavement subgrade materials in Toronto, Ontario. A modified CBR apparatus was utilized, incorporating orifices drilled into the CBR mold to monitor matric suction, ψ and water content using MPS-6 (or TEROS-21) and EC-5 sensors, respectively. The measured CBR and ψ values along with resilient moduli were then used to develop correlations to estimate resilient modulus, M_R of compacted soils required for Level 2 design in the MEPDG. The modified CBR testing procedures used in this study are anticipated to be applicable to other soils for estimating M_R, aiding in the design of pavement subgrade materials.

{"title":"Mechanistic-empirical method of pavement design extending unsaturated soil mechanics","authors":"Kenneth O. Omenogor , Won Taek Oh , Sai K. Vanapalli","doi":"10.1016/j.trgeo.2025.101569","DOIUrl":"10.1016/j.trgeo.2025.101569","url":null,"abstract":"<div><div>Pavement system that typically constitutes of different soil and material layers is located within the vadose zone that is above the groundwater table, which is in an unsaturated condition. Due to this reason, suction is a crucial stress state variable for interpreting the behavior of pavements in the vadose zone. The Mechanistic-Empirical Pavement Design Guide (MEPDG) serves as a comprehensive design tool that accounts for both the resilient response and environmental influences on pavement material properties. In this study, a series of California Bearing Ratio (<em>CBR</em>) tests were conducted on both saturated and unsaturated compacted soils that are commonly used as pavement subgrade materials in Toronto, Ontario. A modified <em>CBR</em> apparatus was utilized, incorporating orifices drilled into the <em>CBR</em> mold to monitor matric suction, <em>ψ</em> and water content using MPS-6 (or TEROS-21) and EC-5 sensors, respectively. The measured <em>CBR</em> and <em>ψ</em> values along with resilient moduli were then used to develop correlations to estimate resilient modulus, <em>M<sub>R</sub></em> of compacted soils required for Level 2 design in the MEPDG. The modified <em>CBR</em> testing procedures used in this study are anticipated to be applicable to other soils for estimating <em>M<sub>R</sub></em>, aiding in the design of pavement subgrade materials.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101569"},"PeriodicalIF":4.9,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143851709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An analytical solution for evaluating the progressive bending failure of columns in soft ground under embankment loading

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-04-16 DOI: 10.1016/j.trgeo.2025.101563

Xiaoxuan Yu , Gaolin Xie , Gang Zheng , Haizuo Zhou , Jinshan Wang , Fengwei Li

Rigid columns are commonly employed in soft clay embankment construction due to their high shear and bending capacities. However, conventional design methods often oversimplify the interaction between the columns and the surrounding soil by assuming uniform shear failure across all columns. This simplification can result in overestimations of embankment stability and may fail to account for potential unforeseen failures. In response to this limitation, the present study introduces a novel analytical framework, validated through centrifuge testing, to systematically assess the stability of soft ground reinforced with columns. Unlike conventional approaches, the methodology accounts for both bending failure mechanisms and progressive failure behavior during rapid embankment construction. It explicitly incorporates column-soil interaction, providing a more realistic stability assessment. Analytical expressions derived in the study quantify lateral forces exerted on the columns, offering insight into failure propagation from the embankment toe to the center. By integrating critical factors such as geometric parameters and soil properties, the methodology captures the variations in maximum bending moments, thus enhancing the predictive accuracy. This analysis of column progressive behavior enhances the understanding of embankment stability and provides a solid foundation for geotechnical design decisions.

{"title":"An analytical solution for evaluating the progressive bending failure of columns in soft ground under embankment loading","authors":"Xiaoxuan Yu , Gaolin Xie , Gang Zheng , Haizuo Zhou , Jinshan Wang , Fengwei Li","doi":"10.1016/j.trgeo.2025.101563","DOIUrl":"10.1016/j.trgeo.2025.101563","url":null,"abstract":"<div><div>Rigid columns are commonly employed in soft clay embankment construction due to their high shear and bending capacities. However, conventional design methods often oversimplify the interaction between the columns and the surrounding soil by assuming uniform shear failure across all columns. This simplification can result in overestimations of embankment stability and may fail to account for potential unforeseen failures. In response to this limitation, the present study introduces a novel analytical framework, validated through centrifuge testing, to systematically assess the stability of soft ground reinforced with columns. Unlike conventional approaches, the methodology accounts for both bending failure mechanisms and progressive failure behavior during rapid embankment construction. It explicitly incorporates column-soil interaction, providing a more realistic stability assessment. Analytical expressions derived in the study quantify lateral forces exerted on the columns, offering insight into failure propagation from the embankment toe to the center. By integrating critical factors such as geometric parameters and soil properties, the methodology captures the variations in maximum bending moments, thus enhancing the predictive accuracy. This analysis of column progressive behavior enhances the understanding of embankment stability and provides a solid foundation for geotechnical design decisions.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101563"},"PeriodicalIF":4.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143868796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0