Transportation Geotechnics最新文献_第3页

Spring load restriction methods: A comprehensive review 弹簧载荷限制方法：全面回顾

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-25 DOI: 10.1016/j.trgeo.2025.101532

Muchun Liu , Behnam Azmoon , Mohammad Hossein Tavakoli Dastjerdi , Aynaz Biniyaz , Zhen Leo Liu

In cold regions, the seasonal freeze–thaw cycles constitute a significant challenge for pavement, leading to structural impairments and diminished long-term performance. During winter, the frozen water and ice formations increase pavement stiffness and bearing capacity. However, during the spring thaw, the liquid water above the frozen layer can be trapped by the impermeable frozen soil. This leads to a reduction in soil shear strength and pavement bearing capacity, resulting in deformations and damage to the roads. To mitigate these costs, Spring/Seasonal Load Restrictions (SLRs) policies have been implemented to limit axle loads and protect roads during the thaw-weakening. The success of SLR policies depends on an accurate estimation of the start date and duration of the reduced bearing capacity period. SLRs should also strike a balance between minimizing pavement damage and allowing traffic to flow freely as possible. This paper presents a comprehensive review of the existing SLR practices aṇssociated with their underlying mechanisms and different categories. SLR practices in Northern America are also summarized to evaluate the industry standards. In-depth discussions are added at the end based on this review to highlight the knowledge gaps and drawbacks of the current state of the practice.

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引用次数: 0

Model tests study of multi-layer geosynthetic-reinforced pile-supported embankments and evaluation of analytical design models

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-20 DOI: 10.1016/j.trgeo.2025.101521

Da Zhang , Guangqing Yang , Ting Li , Peng Xu , Penghui Su

Single and multi-layer geosynthetic-reinforced pile-supported (GRPS) embankments are widely used in practice. Various analytical design models were developed to analyze GRPS embankments. However, engineering experience has shown that the performance of multi-layer GRPS embankments differs from that of single-layer GRPS embankments. The applicability of these analytical design models based on different assumptions has not been fully validated. This paper conducted the physical model test on multi-layer GRPS embankments to clarify their macroscopic mechanical properties. The performance of eight analytical design models under different relative embankment heights was assessed based on the results of the physical model test, using arching efficiency and reinforcement strain as comparison parameters. The results from the physical model test indicated that increasing the number of reinforcement layers in GRPS embankments can more significantly enhance their performance in terms of load transfer and deformation control, as compared to increasing the reinforcement strength of single-layer GRPS embankments. Unlike the membrane behavior exhibited by single-layer reinforcement, the mechanism of multi-layer reinforcement is closer to beam behavior due to the interlock between the reinforcements and the granular fill. Additionally, there is a positive correlation between the prediction accuracy of analytical design models and the relative embankment height, both in predicting the arching efficiency and the reinforcement strain. The accuracy of selected analytical design models in predicting reinforcement strain is found to be weaker in comparison to their predictive capabilities for arching efficiency. Finally, the EBGEO model has good performance, which is grounded in limit equilibrium theory, considers subsoil bearing capacity, and assumes a triangular distribution of the overburden load on the reinforcement.

单层和多层土工合成材料加固桩支撑（GRPS）堤坝在实践中得到广泛应用。人们开发了各种分析设计模型来分析 GRPS 堤坝。然而，工程经验表明，多层土工合成材料加固路堤的性能与单层土工合成材料加固路堤的性能有所不同。这些基于不同假设的分析设计模型的适用性尚未得到充分验证。本文对多层 GRPS 路堤进行了物理模型试验，以明确其宏观力学性能。根据物理模型试验的结果，以起拱效率和钢筋应变为比较参数，评估了八个分析设计模型在不同相对路堤高度下的性能。物理模型试验结果表明，与提高单层 GRPS 路堤的加固强度相比，增加 GRPS 路堤的加固层数能更显著地提高其荷载传递和变形控制性能。与单层加固所表现出的膜行为不同，多层加固的机理更接近于梁行为，因为加固层与颗粒填料之间存在互锁关系。此外，在预测起拱效率和加固应变时，分析设计模型的预测精度与路堤相对高度呈正相关。选定的分析设计模型在预测钢筋应变方面的准确性要弱于其对起拱效率的预测能力。最后，EBGEO 模型性能良好，该模型以极限平衡理论为基础，考虑了基土承载力，并假定加固上的覆土荷载呈三角形分布。

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引用次数: 0

Visualization of the microscopic mechanism of slurry infiltration and filter cake formation for slurry shield tunneling in saturated sand: A microfluidic chip experiment

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-20 DOI: 10.1016/j.trgeo.2025.101529

Yanbo Chen , Hao Liu , Yufeng Gao , Xiaowei Ye , Haowen Guo , Yunqi Gao , Yandong Lv

This study investigated the effects of slurry concentration and pressure on the micro-mechanisms of the slurry infiltration and filter cake formation through microfluidic chip experiments. The formation process of the clogging skeletons and filter cake was revealed. The formation time of clogging skeletons, particle deposition area, average clogging depth and clogging frequency were measured to evaluate the effects of slurry concentration and pressure. The results show that the bentonite particles can clog the pores through the effects of sieving and bridging, thereby forming weakly-permeable clogging skeletons. Subsequent particles deposit on the clogging skeletons and the filter cake begins to form. Higher slurry concentration can accelerate the clogging skeleton formation and enhances its stability. Increasing the concentration from 30 g/l to 60 g/l can increase the frequency of bridging-induced clogging by 2.66 %, leading to a 26 % decrease in the average clogging depth. The shallower clogging depth facilitates a larger external deposition area, significantly reducing the filter cake permeability. Higher slurry pressure can also accelerate the clogging skeleton formation and compacts the external deposited particles. Increasing the initial pressure from 30 kPa to 50 kPa can decrease the frequency of bridging-induced clogging by 2.41 % and increase the average clogging depth by 13 %, which induces the larger internal deposition area and lower filter cake permeability. Considering the effects of the cutter tool penetration depth and rotation frequency on the filter cake, it is recommended the concentration and excess pressure of the slurry used in the engineering applications should not be less than 60 g/l and 50 kPa, respectively.

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引用次数: 0

Site-specific soil water characteristic curve prediction with extremely scarce data using data-driven hierarchical Bayesian model

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-19 DOI: 10.1016/j.trgeo.2025.101527

Menglu Huang, Shin-Ichi Nishimura, Toshifumi Shibata, Linghao Huang, Shiying Zheng

The soil-water characteristic curve (SWCC) is fundamental for understanding the hydro-mechanical behavior of unsaturated soils and is widely applied in various fields. However, determining the SWCC through laboratory experiments is time-consuming. As a result, developing efficient prediction models for SWCC is highly valuable for timely decision-making. Existing methods face fundamental limitations: Bayesian approaches rely on predefined empirical models that may fail to fully capture soil–water interactions, while current data-driven machine learning models struggle to handle extremely sparse measurements, incomplete inputs and uncertainty quantification. To address these challenges, this study introduces a data-driven hierarchical Bayesian model (HBM) that integrates an indirect database with extremely sparse site-specific measurements (e.g., fewer than four data points) to reliably predict the SWCC. The HBM operates in two stages where hyperparameters are first estimated from the database to establish a prior model, and then in the inference stage, the prior model is refined through transfer learning to generate a quasi-site-specific posterior model. Through conjugate priors and Gibbs sampling, this approach enables robust SWCC predictions with severely limited data and/or incomplete soil parameters. A comprehensive drying SWCC database with ten essential soil parameters is compiled to train and validate the model through three case studies and leave-one-site-out cross-validation. The results show that the HBM outperforms widely used machine learning models, such as Artificial Neural Networks and Extreme Gradient Boosting, offering a robust solution for SWCC prediction under site-specific data constraints.

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引用次数: 0

Effect of installation damage on the behavior of a polypropylene geogrid in an aggressive environment

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-19 DOI: 10.1016/j.trgeo.2025.101523

Linda Naga , Mohamed Chikhaoui , Daniele Cazzuffi , Lynda Djerbal

This study explores the effect of installation damage on the behavior of a polypropylene geogrid in an aggressive environment, providing a more realistic assessment of the long-term product behavior under severe conditions. The study’s novelty resides in evaluating the combined effect of installation damage and chemical degradation on the geosynthetic at microscopic and macroscopic scales. To this end, experimental tests were conducted in two phases. In the first phase, a full-scale field installation test and an accelerated aging test— specifically, immersion in sulfuric acid (H₂SO₄) at a concentration of 3.1 mol/L at 80 °C—were performed separately on a virgin geogrid. In the second phase, the geogrid previously damaged under the installation test was exposed to the accelerated aging test (combined degradation). The damage sustained by the geogrid after the degradation tests was evaluated by monitoring changes in its mechanical behavior using the tensile test. In addition, differential scanning calorimetry analysis was performed to assess the evolution of the thermal and morphological properties of the polypropylene, while the surface morphology of the geogrid was examined through scanning electron microscopy. The findings demonstrated that chemical attack has a less pronounced effect on the thermal and mechanical behavior of the geogrid previously damaged during the installation process compared to the undamaged geogrid. Specifically, throughout the aging time, the reductions in tensile strength ranged from 17.59 − 26.38 % following combined degradation, compared to 27.19 − 39.75 % after the aging test (single degradation). This investigation underscores the significance of considering the combined effects of degradation agents to enhance the predictability of geosynthetics’ performance in real conditions, thereby ensuring the optimization of infrastructure longevity.

这项研究探讨了安装损坏对聚丙烯土工格栅在侵蚀性环境中的行为的影响，从而对产品在恶劣条件下的长期行为进行了更真实的评估。这项研究的创新之处在于从微观和宏观尺度评估了安装损坏和化学降解对土工合成材料的综合影响。为此，实验测试分两个阶段进行。在第一阶段，对原生土工格栅分别进行了全面的现场安装试验和加速老化试验，特别是在 80 °C 下浸泡在浓度为 3.1 mol/L 的硫酸（H2SO4）中。在第二阶段，先前在安装试验中受损的土工格栅将接受加速老化试验（综合降解）。通过拉伸试验监测土工格栅机械性能的变化，评估土工格栅在降解试验后受到的损坏。此外，还进行了差示扫描量热分析，以评估聚丙烯的热特性和形态特性的变化，并通过扫描电子显微镜检查了土工格栅的表面形态。研究结果表明，与未受损的土工格栅相比，化学侵蚀对安装过程中受损的土工格栅的热性能和机械性能的影响较小。具体来说，在整个老化过程中，综合降解后的拉伸强度降低了 17.59% - 26.38%，而老化试验（单一降解）后的拉伸强度降低了 27.19% - 39.75%。这项调查强调了考虑降解剂综合效应的重要性，以提高土工合成材料在实际条件下性能的可预测性，从而确保优化基础设施的使用寿命。

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引用次数: 0

Multiphysics simulation of frost heave in unsaturated road systems under covering effect

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-19 DOI: 10.1016/j.trgeo.2025.101526

Lin Li , Zepeng Zhang , Weiling Zu , Panpan Li , Weibing Gong

The frost heave of road systems under the covering effect involves the coupled transport of water, heat, and gas, along with the dynamic phase transition of water, vapor, and ice, resulting in a complex multi-physical field coupling process. This study presents a multi-physics numerical model to investigate the frost heave process of road systems in cold regions. The model not only considers the pavement covering effect and the multi-layered structure of the road, but also represents the multi-field coupling and multiphase transitions involved in the system. The model validation is conducted by comparing it with experimental results from a well-documented sample experiment, which simplifies the initial and boundary conditions of the road system calculation profile model. Following the multi-field coupling analysis, a parametric analysis is conducted to explore the impact of different roadbed parameters on the covering effect. Special attention is given to the effects of initial moisture content, temperature gradient, cooling rate, and compactness of fillers on the frost heave process. The results show that the migration and phase transition of vapor impact the freezing process of road systems. In the stable phase of the freeze process, the moisture content at the top of the road substantially exceeds the initial level, a phenomenon driven by vapor migration. This multi-physics simulation can potentially serve as a guidance for studying the frost heave mechanism of road systems in cold regions.

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引用次数: 0

Research on the hydrothermal process and deformation law of the fill-cut transition section subgrade under dynamic load

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-17 DOI: 10.1016/j.trgeo.2025.101524

Jinbang Zhai , Ze Zhang , Delong Zhang , Kun Zhang , Qihao Yu , Yaqi Zhang

The fill-cut transition section subgrade (FCTSS) is a weak point in subgrade damage. Indoor experiments were conducted to clarify the deformation damage mechanism. It was found that repeated dynamic load leads to upward migration of moisture along the fill-tangent interface and the formation of moisture migration channels. The overall moisture of the soil samples increased under the condition of continuous moisture migration and aggregation. The increase in moisture weakened the strength of the soil, resulting in an increase in moisture accumulation in the region corresponding to the location of greater compressive deformation, which is also the location where damage occurred. Therefore, in order to prevent the effect of dynamic load on the deformation damage of the subgrade, the external recharge of FCTSS should be controlled. This study can provide a valuable reference for the construction and protection of subgrade in the fill-cut transition section in loess areas.

引用次数: 0

Frost heave evaluation and prediction of high-speed railway subgrade with coarse filler in high altitude seasonal frozen region, northwest China

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-16 DOI: 10.1016/j.trgeo.2025.101520

Xuyang Wu , Zhanju Lin , Fujun Niu , Xingwen Fan , Minghao Liu , Chunqing Li , Yunhu Shang

The subgrade frost heave problem in high altitude seasonal frozen regions is influenced by extreme climatic conditions, geological factors, subgrade structure, and other external variables. Consequently, controlling the frost heave issue becomes challenging. Based on 8 years field monitoring of Lanzhou-Xinjiang high-speed railway (LXHR), the engineering effectiveness of current subgrade anti-frost heave measures in seasonal frozen regions is comprehensively evaluated, and long-term frost heave of subgrade is predicted. The results demonstrate that Geological conditions exert a significant influence on both subgrade frost heave and frozen depth, and the specific manifestations of frost heave are as follows: intermountain basin > Gobi desert > diluvial plain, while the frozen depths are follows: diluvial plain > Gobi desert ≈ intermountain basin. The frost heave in the middle and upper layer of the subgrade (above 1.5 m) constitutes approximately 80 %–87.5 % of the total frost heave. Considering the cumulative increase in subgrade frost heave over time, the subgrade with coarse particle material replacement, and the “two cloth and one film” technique may not be conducive to long-term stability. It is predicted that after 30 years of operation, the subgrade antifreeze layer may transition from being non-sensitive of frost heave to becoming sensitive.

{"title":"Frost heave evaluation and prediction of high-speed railway subgrade with coarse filler in high altitude seasonal frozen region, northwest China","authors":"Xuyang Wu , Zhanju Lin , Fujun Niu , Xingwen Fan , Minghao Liu , Chunqing Li , Yunhu Shang","doi":"10.1016/j.trgeo.2025.101520","DOIUrl":"10.1016/j.trgeo.2025.101520","url":null,"abstract":"<div><div>The subgrade frost heave problem in high altitude seasonal frozen regions is influenced by extreme climatic conditions, geological factors, subgrade structure, and other external variables. Consequently, controlling the frost heave issue becomes challenging. Based on 8 years field monitoring of Lanzhou-Xinjiang high-speed railway (LXHR), the engineering effectiveness of current subgrade anti-frost heave measures in seasonal frozen regions is comprehensively evaluated, and long-term frost heave of subgrade is predicted. The results demonstrate that Geological conditions exert a significant influence on both subgrade frost heave and frozen depth, and the specific manifestations of frost heave are as follows: intermountain basin > Gobi desert > diluvial plain, while the frozen depths are follows: diluvial plain > Gobi desert ≈ intermountain basin. The frost heave in the middle and upper layer of the subgrade (above 1.5 m) constitutes approximately 80 %–87.5 % of the total frost heave. Considering the cumulative increase in subgrade frost heave over time, the subgrade with coarse particle material replacement, and the “two cloth and one film” technique may not be conducive to long-term stability. It is predicted that after 30 years of operation, the subgrade antifreeze layer may transition from being non-sensitive of frost heave to becoming sensitive.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"51 ","pages":"Article 101520"},"PeriodicalIF":4.9,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454118","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

Probabilistic demand models and fragility analysis of railway embankments subjected to multi-pulse ground motions

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-15 DOI: 10.1016/j.trgeo.2025.101522

Pan SI , Liang TANG , Shuang TIAN , Yanfang LIU , Xianzhang LING

The pulse-like ground motion has a substantial impact on long-period structures such as railway embankments. However, previous studies have focused more on comparative analyses of ground motions with and without pulses, without distinguishing between multi-pulse and single-pulse ground motions. This study aims to quantitatively assess the differences in seismic damage to railway embankments when subjected to various pulse-like ground motions, utilizing the seismic fragility analysis method. We executed an incremental dynamic analysis of railway embankments to construct a probabilistic seismic demand model. The most effective intensity measures (IMs) were chosen from among 20 IMs using criteria of correlation, practicality, efficiency, and proficiency. The conditional probability function facilitated fragility curves by applying the optimal IMs and the engineering demand parameters, which represented the peak permanent settlement on the surface of the railway embankment. The results demonstrated the superiority of structure-specific IMs (e.g., velocity spectrum intensity and housner intensity) over acceleration-, velocity-, displacement-, and time-related IMs. The findings revealed that multi-pulse ground motions significantly impacted the uncertainty of railway embankment damage more than single-pulse ground motions, and ignoring their effects led to an underestimation of their fragility in all states of damage.

{"title":"Probabilistic demand models and fragility analysis of railway embankments subjected to multi-pulse ground motions","authors":"Pan SI , Liang TANG , Shuang TIAN , Yanfang LIU , Xianzhang LING","doi":"10.1016/j.trgeo.2025.101522","DOIUrl":"10.1016/j.trgeo.2025.101522","url":null,"abstract":"<div><div>The pulse-like ground motion has a substantial impact on long-period structures such as railway embankments. However, previous studies have focused more on comparative analyses of ground motions with and without pulses, without distinguishing between multi-pulse and single-pulse ground motions. This study aims to quantitatively assess the differences in seismic damage to railway embankments when subjected to various pulse-like ground motions, utilizing the seismic fragility analysis method. We executed an incremental dynamic analysis of railway embankments to construct a probabilistic seismic demand model. The most effective intensity measures (IMs) were chosen from among 20 IMs using criteria of correlation, practicality, efficiency, and proficiency. The conditional probability function facilitated fragility curves by applying the optimal IMs and the engineering demand parameters, which represented the peak permanent settlement on the surface of the railway embankment. The results demonstrated the superiority of structure-specific IMs (e.g., velocity spectrum intensity and housner intensity) over acceleration-, velocity-, displacement-, and time-related IMs. The findings revealed that multi-pulse ground motions significantly impacted the uncertainty of railway embankment damage more than single-pulse ground motions, and ignoring their effects led to an underestimation of their fragility in all states of damage.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"52 ","pages":"Article 101522"},"PeriodicalIF":4.9,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628188","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

Mechanical behaviors of the geocell reinforced graded aggregates under train loading: Based on Indoor tests and DEM

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2025-02-10 DOI: 10.1016/j.trgeo.2025.101514

Rongwei Fan , Junjie Huang , Yanfei Pei , Zhichao Huang , Haokun Zhang , Zongyu Zhang , Aibo Luo , Qian Su

Usually, a graded-aggregates layer with a given thickness is laid between a rigid subgrade (box subgrade, pile-plank subgrade) and a ballastless track structure. Such a configuration is realized to achieve features such as dynamic buffering, vibration reduction, energy dissipation, and limitation of uneven settlement. Geocells are typically used to reinforce the graded aggregates layer by enhancing its strength and stiffness. A dynamic test device was independently developed to investigate the mechanical behavior of geocell-reinforced graded aggregates under train loading. The test device can simulate the cyclic train loading and lateral confining pressure on graded aggregates. Subsequently, a comparative test of graded aggregates with geocell and without geocell was carried out by using the device. The above said experiments were simulated by a 3D discrete-element approach that considered the actual shape of the graded aggregate particles. The macroscopic mechanical property changes of graded aggregate under train loads were analyzed from microscopic behaviors such as particle contact and particle migration. This study is intended to provide a basis for optimizing and improving the dynamic performance and evaluation of the ballastless track sandwich subgrade with an upper rigid layer, a middle flexible layer, and a lower rigid layer during long-term service.

{"title":"Mechanical behaviors of the geocell reinforced graded aggregates under train loading: Based on Indoor tests and DEM","authors":"Rongwei Fan , Junjie Huang , Yanfei Pei , Zhichao Huang , Haokun Zhang , Zongyu Zhang , Aibo Luo , Qian Su","doi":"10.1016/j.trgeo.2025.101514","DOIUrl":"10.1016/j.trgeo.2025.101514","url":null,"abstract":"<div><div>Usually, a graded-aggregates layer with a given thickness is laid between a rigid subgrade (box subgrade, pile-plank subgrade) and a ballastless track structure. Such a configuration is realized to achieve features such as dynamic buffering, vibration reduction, energy dissipation, and limitation of uneven settlement. Geocells are typically used to reinforce the graded aggregates layer by enhancing its strength and stiffness. A dynamic test device was independently developed to investigate the mechanical behavior of geocell-reinforced graded aggregates under train loading. The test device can simulate the cyclic train loading and lateral confining pressure on graded aggregates. Subsequently, a comparative test of graded aggregates with geocell and without geocell was carried out by using the device. The above said experiments were simulated by a 3D discrete-element approach that considered the actual shape of the graded aggregate particles. The macroscopic mechanical property changes of graded aggregate under train loads were analyzed from microscopic behaviors such as particle contact and particle migration. This study is intended to provide a basis for optimizing and improving the dynamic performance and evaluation of the ballastless track sandwich subgrade with an upper rigid layer, a middle flexible layer, and a lower rigid layer during long-term service.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":"51 ","pages":"Article 101514"},"PeriodicalIF":4.9,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395380","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