Transportation Geotechnics最新文献_第2页

Performance evaluation of high early strength micro-expansion geopolymer grout potentially used for sustainable road infrastructure 可用于可持续道路基础设施的高早期强度微膨胀土工聚合物灌浆料性能评估

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-17 DOI: 10.1016/j.trgeo.2024.101400

{"title":"Performance evaluation of high early strength micro-expansion geopolymer grout potentially used for sustainable road infrastructure","authors":"","doi":"10.1016/j.trgeo.2024.101400","DOIUrl":"10.1016/j.trgeo.2024.101400","url":null,"abstract":"<div><div>This study aimed to develop a high early strength micro-expansion geopolymer grout material derived from recycled concrete and ground granulated blast-furnace slag (GGBS), which can be used to fill the subgrade voids and strengthen weak subgrade. A series of grout materials with varying proportions of recycled concrete were prepared, and their setting time, flowability, and strength characteristics were evaluated. The results indicated that the grout material containing 50 % recycled concrete had a final setting time of 29 min, a flow time of 15.2 s, and a 7-day compressive strength of 40.6 MPa, all of which met the requirements for subgrade grout materials. To further enhance the performance of the grout, the additives including 2 % calcium chloride (CaCl<sub>2</sub>), 5 % magnesium oxide (MgO), and 5 % united expansive agent (UEA) were used. Results showed that the samples containing 50 % recycled concrete and 2 % CaCl<sub>2</sub> exhibited a 26.5 % increase in strength after 100 min of curing, while MgO and UEA reduced shrinkage by 112.5 % and 90.0 %, respectively. Additionally, microstructural analysis using SEM and XRD provided valuable insights into the complex interactions between components and their effects on material integrity. The results demonstrated that the use of CaCl<sub>2</sub> accelerated the hydration reaction, enhancing early strength, while the expansion agents MgO and UEA mitigated shrinkage and achieved micro-expansion at low concrete content. This study addresses environmental concerns by incorporating recycled materials, positioning the developed geopolymer grout as a sustainable, high-performance alternative in road construction. Integrating waste-derived components and innovative additives represents a significant step towards advancing sustainable practices in infrastructure development.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532859","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

Fiber-reinforced shotcrete lining for stabilizing rock blocks around underground cavities 用于稳定地下空洞周围岩块的纤维增强喷射混凝土衬里

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-16 DOI: 10.1016/j.trgeo.2024.101407

{"title":"Fiber-reinforced shotcrete lining for stabilizing rock blocks around underground cavities","authors":"","doi":"10.1016/j.trgeo.2024.101407","DOIUrl":"10.1016/j.trgeo.2024.101407","url":null,"abstract":"<div><div>Fiber-reinforced shotcrete is a high-performance material that presents some special characteristics, which can provide some suitable applications in the excavation of underground cavities. The presence of fibers induces an increase in the tensile strength, flexural strength and shear strength in the concrete, as well as allowing a ductile rather than brittle type of behavior. It can be used to create a lining of the underground cavity that allows the stabilization of rock blocks that show a tendency to slip or fall (from the side walls or from the crown area, respectively). In this work, some full-scale tests on the fiber-reinforced shotcrete lining are presented. From these tests, it was possible to measure the behavior of this material when it is loaded locally: it is the same type of action produced by the rock block when it is held back from falling or slipping. The results obtained have allowed to characterize this type of material from a mechanical point of view. A subsequent detailed analysis of the stability of rock blocks surrounding an underground cavity permitted to determine the static stabilizing contribution offered by the fiber-reinforced shotcrete lining, leading to the definition of the minimum thickness required, in relation to the type of block that is present (shape and size). It was possible to predict how a lining thickness of about 3.5 cm is able to stabilize (just 15 min after its spraying) rock blocks with an exposed surface area of up to 10 m<sup>2</sup> and a distance of the internal vertex from the border of the cavity of up to 3 <em>m</em>.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The impact of Microbially Induced Calcite Precipitation (MICP) on sand internal erosion resistance: A microfluidic study 微生物诱导方解石沉淀（MICP）对沙子内部抗侵蚀性的影响：微流控研究

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-15 DOI: 10.1016/j.trgeo.2024.101404

{"title":"The impact of Microbially Induced Calcite Precipitation (MICP) on sand internal erosion resistance: A microfluidic study","authors":"","doi":"10.1016/j.trgeo.2024.101404","DOIUrl":"10.1016/j.trgeo.2024.101404","url":null,"abstract":"<div><div>Fine particle internal erosion involves the detachment, transport, and deposition of fine particles within soil, significantly impacting agriculture, engineering, and environmental protection. Microbially induced calcite precipitation (MICP) has proven to be an effective method for controlling internal erosion. To optimize MICP protocols for effective erosion control, understanding the microscopic mechanisms by which MICP reduces fine particle erosion is essential but remains unclear. In this study, microfluidic chip experiments were conducted to observe the characteristics of calcium carbonate crystals and fine particles before and after MICP reinforcement and erosion. Through quantitative analysis of the calcium carbonate produced by MICP and eroded fine particles, the effects of bacterial density, concentration of cementation solution, and flow rate on the efficiency of MICP in resisting soil internal erosion were investigated. In addition, three primary mechanisms by which MICP reduces fine particle erosion were identified. Firstly, <em>in situ</em> sand stabilization occurs when calcium carbonate generated by MICP bonds and encapsulates fine particles, forming larger particles that remain stable under erosive flow conditions. Secondly, regional sand stabilization is achieved as MICP-produced calcium carbonate crystals narrow or block the flow channels, preventing extensive migration of fine particles. Lastly, adjacent particle stabilization is facilitated by calcium carbonate crystals, which remain stable during water flow erosion and alter the erosion flow lines, creating zones adjacent to the crystals where fine particle movement is minimized. These findings provide a deeper understanding of the role of MICP in erosion control and can inform the development of more effective erosion mitigation strategies.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532408","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

Radar forward modeling and intelligent identification of shallow subgrade defects 浅层路基缺陷的雷达前向建模和智能识别

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-15 DOI: 10.1016/j.trgeo.2024.101385

引用次数: 0

A novel Bi-LSTM method fusing current and historical data for tunnelling parameters of shield tunnel 融合当前和历史数据的新型 Bi-LSTM 方法，用于测量盾构隧道的隧道参数

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-15 DOI: 10.1016/j.trgeo.2024.101402

{"title":"A novel Bi-LSTM method fusing current and historical data for tunnelling parameters of shield tunnel","authors":"","doi":"10.1016/j.trgeo.2024.101402","DOIUrl":"10.1016/j.trgeo.2024.101402","url":null,"abstract":"<div><div>Reasonable shield tunnelling parameters play a crucial role in controlling ground stability and enhancing tunnelling efficiency. Predicting shield tunnelling parameters before excavation is of paramount importance. A novel deep learning method is introduced, integrating bidirectional long short-term memory (Bi-LSTM) layers, and fully connected (FC) layers to fuse current and historical data for shield tunnelling parameters prediction. Historical data captures the impact of excavated sections on the current predicted ring, while current data considers present conditions. A feature fusion method eliminates dimensional differences between historical and current data. The resulting tensor, encompassing both data types, is fed into the FC layer to generate predictions. The effectiveness of the method is demonstrated by predicting shield cutter head torque for Qingdao Metro Line 4 in China, outperforming traditional Bi-LSTM, MLP and RF methods significantly. Ablation studies further analyze the impact of different component modules and structural parameters on model performance. Overall, this innovative approach offers accurate shield tunnelling parameters prediction, enhancing ground stability and tunnelling efficiency.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446687","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

A frictional arch model for pile-cap-beam-supported embankment 桩帽-梁支撑路堤的摩擦拱模型

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-15 DOI: 10.1016/j.trgeo.2024.101403

{"title":"A frictional arch model for pile-cap-beam-supported embankment","authors":"","doi":"10.1016/j.trgeo.2024.101403","DOIUrl":"10.1016/j.trgeo.2024.101403","url":null,"abstract":"<div><div>The pile-cap-beam-supported (PCBS) system can strength the soil arching effect of embankment, increase the lateral stiffness, bending resistance and vertical bearing capacity of the rigid pile, however there is no frictional soil arch model of PCBS embankment. In this paper, first a frictional arch model for PCBS embankment modified from Russell’s frictional arching model was proposed. The proposed model in this paper considers the algorithm of lateral pressure coefficient <em>k</em> and a changing critical height of soil arch. In this new method, the influence of pile spacing, filling properties, height and pile spacing on critical height soil arch was comprehensively considered. Second, a series of numerical cases were performed to verify the effectiveness of the proposed model and study the arching effect of PCBS embankment. By comparing the vertical stress and settlement between the theoretical and simulation results, the rationality of the proposed method to estimate the stress and critical height of arch was validated. The effectiveness of the proposed method was further validated by comparing loading efficacy to a reported case. Last, the stress and deformation of PCBS and pile-cap-supported (PCS) embankment were analyzed and the superiority of PCBS system in improving the performance of embankment was observed finally.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142531960","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

Investigation on internal evolution process of slope under seismic loading: insights from a transparent soil test and shaking table test 地震荷载下斜坡内部演变过程研究：透明土壤试验和振动台试验的启示

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-12 DOI: 10.1016/j.trgeo.2024.101399

{"title":"Investigation on internal evolution process of slope under seismic loading: insights from a transparent soil test and shaking table test","authors":"","doi":"10.1016/j.trgeo.2024.101399","DOIUrl":"10.1016/j.trgeo.2024.101399","url":null,"abstract":"<div><div>Earthquakes are a primary factor in triggering slope instability and pose a serious threat to transportation. However, current research on the internal deformation of slopes under seismic loading remains limited. To investigate the effects of different seismic loadings on the evolution process and failure mode of slopes, a novel experiment combining transparent soil materials and shaking table tests was proposed in this study. Using a self-designed shaking table system, sine waves with amplitudes of 0.10 g, 0.15 g, and 0.20 g and frequencies of 3 Hz, 5 Hz, and 8 Hz were applied. Based on Particle Image Velocimetry (PIV) technology and non-intrusive monitoring techniques, displacement and velocity contour maps, whole-field average displacement and failure mechanism of the slope were analyzed. The results show that, as the vibration persists, the slope transitions from initial shallow linear sliding to overall circular arc sliding, exhibiting an obvious progressive traction failure mode. The evolution process of the slope could be divided into three phases: shallow low-speed sliding phase, overall rapid sliding phase, and overall low-speed sliding phase. Furthermore, the amplitude of seismic loading has a greater influence on slope deformation compared to its frequency. This novel experiment offers important insights into the internal evolution process of slopes under seismic loading.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446685","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

The influence of sand content on dynamic behaviors of ballast bed from a multiscale perspective 从多尺度角度看含沙量对压载床动态行为的影响

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-12 DOI: 10.1016/j.trgeo.2024.101401

{"title":"The influence of sand content on dynamic behaviors of ballast bed from a multiscale perspective","authors":"","doi":"10.1016/j.trgeo.2024.101401","DOIUrl":"10.1016/j.trgeo.2024.101401","url":null,"abstract":"<div><div>In desert regions, sand intrusion into the ballast bed is unavoidable, leading to a reduction in the elasticity of the ballast bed and posing potential risks to the service safety. Previous studies have focused on the behaviors of sandy ballast beds in 2D planes using discrete element method (DEM), where sand content is typically calculated utilizing sand areas within the ballast voids, different from that using sand volumes or mass in 3D space. Therefore, the impacts of sand content on the multiscale responses of the ballast bed are not fully addressed. In this paper, 3D full-scale half-sleeper models with various sand contents are established via DEM. Multiscale responses of sandy ballast bed obtained by laboratory tests are utilized to verify the reliability of established models. Simulation results show that macroscopically, sand intrusion increases the stiffness and consequently reduces the elasticity of the ballast bed. Microscopically, sand contaminant restricts the translational acceleration of ballast particles, while simultaneously intensifying the angular acceleration. In terms of particle contact, the anisotropy of the directional distribution of contact force among ballast particles is weakened by sand contaminant. Therefore, the inter-particle contact force among ballast particles becomes more uniform, particularly beneath the rail. A normalized parameter is proposed to quantify the filling effect of sand contaminant, based on which the relationships between multiscale dynamic responses and sand content are linearized. The linearization results indicate that the sand intrusion has more significant impacts on the multiscale responses of the ballast bed under higher loading magnitude.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446686","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

Prediction of resilient modulus with pre-post experimental data of undisturbed subgrade soils using machine learning algorithms 利用机器学习算法，通过未扰动路基土的前后实验数据预测弹性模量

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-09 DOI: 10.1016/j.trgeo.2024.101396

{"title":"Prediction of resilient modulus with pre-post experimental data of undisturbed subgrade soils using machine learning algorithms","authors":"","doi":"10.1016/j.trgeo.2024.101396","DOIUrl":"10.1016/j.trgeo.2024.101396","url":null,"abstract":"<div><div>The resilient modulus (M<sub>R</sub>) of subgrade, which shows relationship between stress and unit deformation of a pavement systems under traffic loads, is a design parameter of the pavement structure. Although a cyclic triaxial test apparatus can be used to directly determine the M<sub>R</sub> of the subgrade in the laboratory, utilizing prediction models based on easily obtainable soil parameters, is a more efficient method when taking time and cost considerations into account. A comprehensive laboratory testing program is designed to create M<sub>R</sub> prediction models using machine learning (ML) algorithms. 70 undisturbed soil samples are subjected to M<sub>R</sub> tests, as well as physical and engineering soil properties tests (water content, field density, specific gravity, gradation, consistency limits, unconfined compressive strength, swell pressure, swell percentage). Soil samples are drilled from a highway that has been in operation for over five years.</div><div>First, a linear model like MLR is used in the study. Next, nonlinear regression models like RF, GBM, LightGBM, CatBoost, and XGBoost algorithms are used. Research findings showed that nonlinear regression models outperformed linear regression models in predicting the M<sub>R</sub> (R<sup>2</sup> > 0.85), with the XGBoost algorithm yielding the best accuracy (R<sup>2</sup> = 0.90). Apart from the primary effects such as confining pressure (σ<sub>3</sub>) and deviatoric stress (σ<sub>d</sub>), it was found that unconfined compressive strength (q<sub>u</sub>), natural water content (w<sub>n</sub>), and swelling percentage (SR) are significant parameters in the prediction of M<sub>R</sub> among all parameters.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422799","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

Life cycle assessment of green binder for organic soil stabilization 用于有机土壤稳定的绿色粘结剂的生命周期评估

IF 4.9 2区工程技术

Transportation Geotechnics Pub Date : 2024-10-06 DOI: 10.1016/j.trgeo.2024.101398

{"title":"Life cycle assessment of green binder for organic soil stabilization","authors":"","doi":"10.1016/j.trgeo.2024.101398","DOIUrl":"10.1016/j.trgeo.2024.101398","url":null,"abstract":"<div><div>Increasing construction on soils with low bearing capacity is a geotechnical challenge currently faced in several parts of the world. Highly compressible organic soils require intervention to improve their mechanical behavior. In this case, mass stabilization with binder is an applicable technique, however the commercial cement used (Ordinary Portland Cement) generates environmental impacts that can be minimized with its replacement by environmentally friendly binders. Blended binders can use secondary materials from the industry (waste or by-products) and promote environmental gains. In this case, this research proposes the use of carbide lime and granulated blast furnace slag with the complement of Portland cement for the stabilization of an organic soil. A comparison of the strength obtained with the blended binder versus Portland cement is analyzed in soil stabilization. A Life Cycle Assessment is performed to verify if the proposed blended binder has environmental benefits in replacing conventional cement. Results show that the blended binder has similar capacity to stabilize the organic clay soil compared to commercial cement. The life cycle analysis showed that the use of secondary materials from industry in the composition of blended binder promotes a significant reduction in environmental impacts assessed.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422798","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