Transportation Geotechnics最新文献

{"title":"Field data-based prediction of local scour depth around bridge piers using interpretable machine learning","authors":"Taeyoon Kim ,&nbsp;Azmayeen R. Shahriar ,&nbsp;Woo-Dong Lee ,&nbsp;Yongjin Choi ,&nbsp;Siyoon Kwon ,&nbsp;Mohammed A. Gabr.","doi":"10.1016/j.trgeo.2025.101567","DOIUrl":"10.1016/j.trgeo.2025.101567","url":null,"abstract":"<div><div>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 <span><math><mrow><mi>y</mi><mo>/</mo><msub><mi>b</mi><mi>n</mi></msub></mrow></math></span> 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.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101567"},"PeriodicalIF":4.9,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143854835","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}

{"title":"Evaluation of the freeze-thaw performance of silane treated pavement subgrade soils","authors":"Md Fyaz Sadiq ,&nbsp;Mohammad Wasif Naqvi ,&nbsp;Bora Cetin ,&nbsp;Emmanuel Adeyanju ,&nbsp;John Daniels ,&nbsp;Michael Uduebor","doi":"10.1016/j.trgeo.2025.101571","DOIUrl":"10.1016/j.trgeo.2025.101571","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101571"},"PeriodicalIF":4.9,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850207","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}

{"title":"Experimental and numerical studies on geosynthetic encased stone columns in saturated and unsaturated soils","authors":"Shakeel Abid Mohammed ,&nbsp;Deendayal Rathod ,&nbsp;Sai K. Vanapalli","doi":"10.1016/j.trgeo.2025.101566","DOIUrl":"10.1016/j.trgeo.2025.101566","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101566"},"PeriodicalIF":4.9,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860572","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}

{"title":"Mechanistic-empirical method of pavement design extending unsaturated soil mechanics","authors":"Kenneth O. Omenogor ,&nbsp;Won Taek Oh ,&nbsp;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_R</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_R</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}

{"title":"An analytical solution for evaluating the progressive bending failure of columns in soft ground under embankment loading","authors":"Xiaoxuan Yu ,&nbsp;Gaolin Xie ,&nbsp;Gang Zheng ,&nbsp;Haizuo Zhou ,&nbsp;Jinshan Wang ,&nbsp;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}

{"title":"Assessing 3D stability of unsaturated embankments/slopes considering water level fluctuations using the minimum potential energy method","authors":"Jiaping Sun ,&nbsp;Pingting Dong ,&nbsp;Tiantang Yu ,&nbsp;Weihua Fang ,&nbsp;Zhiwei Zhou","doi":"10.1016/j.trgeo.2025.101556","DOIUrl":"10.1016/j.trgeo.2025.101556","url":null,"abstract":"<div><div>Water level fluctuations play a crucial role in the stability of unsaturated embankments as they can significantly affect matric suction. This study introduces a novel analytical method based on the minimum potential energy approach to account for these fluctuations in the embankment stability. The critical slip surface (CSS) is modeled as an ellipsoid governed by six parameters, with its determination achieved by minimizing potential energy of the sliding mass, optimized using the sparrow search algorithm (SSA). The method’s validity and accuracy are demonstrated through three case studies that explore the effects of various parameters, including water level, air-entry value ratio, pore size distribution ratio, and shear strength parameters, on stability and CSS location of embankments. The findings reveal that the safety factor (SF) obtained by the proposed method closely align with reference solutions, and highlight that the influence of air-entry value, pore size distribution, and shear strength parameters of foundation on embankment stability is modulated by water level changes. Notably, the failure extent of the embankment broadens with an increasing effective internal friction angle and diminishes with a decrease in pore size distribution ratio.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101556"},"PeriodicalIF":4.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143868674","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}

{"title":"Permanent strain behavior of basalt fiber–reinforced controlled low-strength material under repeated loading","authors":"Dong Geon Son ,&nbsp;Jong-Sub Lee ,&nbsp;Seungjun Kim ,&nbsp;Yong-Hoon Byun","doi":"10.1016/j.trgeo.2025.101570","DOIUrl":"10.1016/j.trgeo.2025.101570","url":null,"abstract":"<div><div>Controlled low-strength material (CLSM) is a flowable, self-leveling backfill material used as an alternative to compacted soil for backfilling trenches, retaining walls, underground cavities, and in pavement construction. This study aims to investigate the permanent deformation of CLSM reinforced with basalt fibers. Basalt fibers with lengths of 6 and 24 mm are incorporated into CLSM mixtures to assess their impact on flowability, setting times, and mechanical properties. Mechanical testing indicates that longer fibers improve tensile strength through a bridging effect. Repeated load triaxial tests are conducted to evaluate the permanent strain behavior under repeated loading. The results show that permanent strain increases with the deviator stress and number of loading cycles. A regression model accounting for the number of loading cycles and deviator stress provides accurate permanent-strain predictions, and the permanent strain behaviors are classified based on the refined shakedown theory. Therefore, the basalt-fiber-reinforced CLSM suggested in this study may be suitable for pavement base material due to its relatively low permanent strain under typical stress conditions.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101570"},"PeriodicalIF":4.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874719","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}

{"title":"Performance Evaluation of Disconnected Piled raft foundation Incorporated with Polystyrene Cushion and Hybrid Geogrid-Geotextile Base","authors":"Mohd Aaqib,&nbsp;Mohd Yousuf Shah","doi":"10.1016/j.trgeo.2025.101565","DOIUrl":"10.1016/j.trgeo.2025.101565","url":null,"abstract":"<div><div>Foundation systems are critical to ensure structural stability, particularly in challenging geotechnical conditions. This study introduces a disconnected piled raft (DPR) foundation system incorporating a polystyrene cushion platform reinforced with geogrid and geotextile layers to enhance load distribution, minimize differential settlement, and improve overall performance. The proposed DPR system addresses the limitations of conventional piled raft foundations by reducing the rigidity at the raft-pile interface and promoting more uniform load transfer. The research methodology involved numerical modelling using PLAXIS-3D and laboratory experiments to evaluate the performance of the DPR system. Material properties of the polystyrene cushion, geogrid, and geotextile were characterized, and boundary conditions were defined to simulate realistic loading scenarios. Comparative analysis with traditional vertical piled raft (VPR) and battered piled raft (BPR) systems was conducted under varying load conditions. Results demonstrated that the DPR system supported a maximum load of 18.2 kN with a settlement of 10 mm, surpassing the performance of connected systems. The settlement efficiency ratio of approximately 32% was significantly higher than the (10-17) % efficiency observed in conventional systems. Additionally, the DPR system exhibited optimized stiffness, achieving equivalent stiffness at 1 kN compared to 17 kN for connected systems, and reduced unit skin friction to -2 kPa, ensuring effective load diffusion. The study concludes that the DPR foundation system offers an innovative solution for modern foundation engineering, providing superior load-bearing capacity, enhanced settlement control, and improved structural efficiency through the integration of advanced geosynthetic materials.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101565"},"PeriodicalIF":4.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143864878","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}

{"title":"Dynamic characteristics and impact load properties of high-speed railway piers under debris flow impact","authors":"Lizhong Jiang ,&nbsp;Wenjie Xiao ,&nbsp;Zhipeng Lai ,&nbsp;Ben Mou","doi":"10.1016/j.trgeo.2025.101562","DOIUrl":"10.1016/j.trgeo.2025.101562","url":null,"abstract":"<div><div>Debris flows, comprising slurry and boulders, pose significant threats to high-speed railway bridges in debris flow-prone regions due to their rapid and unsteady nature. However, research on the dynamic characteristics of high-speed railway bridges under the impact of debris flows remains limited. This study develops a refined numerical model to analyze the impact of debris flow slurry and boulders on high-speed railway piers, utilizing the Smoothed Particle Hydrodynamics (SPH) and Finite Element Method (FEM) coupling method. The model's validity is confirmed by comparing it to experimental data from existing research. The research applies the validated model to examine the dynamic response characteristics of high-speed railway piers of varying heights when subjected to impacts from slurry and boulders. In addition, it proposes simplified load models for these impacts, incorporating corrections to current code formulas. The results indicated that piers of specific types experience varying levels of damage from boulder impacts, with the existing code formulas underestimating peak impact forces. For slurry impacts, the code formulas underestimate peak impact forces, with actual values under low flow depths reaching up to twice the value predicted by the formulas.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101562"},"PeriodicalIF":4.9,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838507","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}

{"title":"Strength deterioration and predictive modeling of coarse-grained soil under penetrating erosion effects","authors":"Yunhao Chen ,&nbsp;Ling Zhang ,&nbsp;Zhongshu Liu ,&nbsp;Yongwei Li ,&nbsp;Jingpeng Tan","doi":"10.1016/j.trgeo.2025.101559","DOIUrl":"10.1016/j.trgeo.2025.101559","url":null,"abstract":"<div><div>This investigation aims to explore the strength deterioration characteristics of coarse-grained soils (CGSs) under penetrating erosion. Unconsolidated undrained (UU) triaxial tests were conducted on untreated specimens and those subjected to four amplitudes of penetrating erosion force (<em>p</em>₀), to examine the impact of penetrating erosion on the shear performance of CGSs with varying mass ratios of mudstone fines (<em>η</em>). Furthermore, a strength prediction model, <em>K</em>_M-C(<em>η</em>, <em>p</em>₀), was developed based on the Mohr-Coulomb (M−C) strength criterion, incorporating both <em>η</em> and <em>p</em>₀ as influencing factors. The results indicate that untreated specimens predominantly exhibit bulging deformation upon failure, whereas treated specimens can be divided into distinct bulging and non-bulging zones, with significant transverse cracks emerging in the transition region between these zones. Moreover, treated CGS specimens demonstrate notable strain-softening behavior, as the deviator stress peak [(<em>σ</em>₁–<em>σ</em>₃)_max] decreases linearly with increasing penetrating erosion force <em>p</em>₀ under the same confining pressure (<em>σ</em>₃). Furthermore, minor variations in confining pressure have little effect on the strength weakening induced by penetrating erosion, and at low confining pressures, both untreated and treated specimens conform to the M−C failure criterion. Additionally, there exists a critical fine content threshold <em>η</em>_critical; when the fine content is below this threshold, increasing it enhances the stability of the CGS skeleton and its resistance to seepage erosion. Conversely, when the fines content exceeds <em>η</em>_critical, the filling effect of the fines weakens the stability of the soil skeleton, thereby reducing its resistance to penetrating erosion. In this investigation, <em>η</em>_critical is determined to be 9.15%. Lastly, the predictive model developed in this study accurately captures the influence of <em>η</em> and <em>p</em>₀ on the strength of CGSs, with the relative error between the measured and predicted strength values ranging from 1.1% to 14.9%.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101559"},"PeriodicalIF":4.9,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828721","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}