Transportation Geotechnics最新文献

{"title":"Predicting strain energy causing soil liquefaction","authors":"","doi":"10.1016/j.trgeo.2024.101419","DOIUrl":"10.1016/j.trgeo.2024.101419","url":null,"abstract":"<div><div>Liquefaction, which typically occurs in saturated sandy soil deposits, is one of the destructive phenomena that can occur during an earthquake. When the soil reaches liquefied state, it loses a significant amount of resistance and stiffness, which often results in widespread catastrophic damages. Therefore, accurate evaluating the potential of soil liquefaction occurrence is of great importance in earthquake geotechnical designs in regions prone to this phenomenon. The strain energy-based approach is a novel robustness technique to evaluate liquefaction potential. In the current research, 165 laboratory data sets from cyclic experiments were collected and analyzed. A predictive model using gene expression programming (GEP) was proposed to assess strain energy needed for occurrence of soil liquefaction. Assessing physical behavior of developed GEP-based model was conducted through sensitivity analysis. Performance of GEP-based was validated by comparing with a series of centrifuge experiments and cyclic triaxial tests results. Subsequently, after experimental verification of numerical modeling, the strain energy required for soil liquefaction under cyclic loading at different conditions were numerically evaluated and compared with the strain energy calculated by proposed model. Finally, the developed GEP-based model was compared with established strain energy-based relationships. The results indicated high precision of proposed GEP-based model in determination of strain energy required for soil liquefaction triggering.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554141","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":"Effect of torsional shear stress on the deformation characteristics of clay under traffic load","authors":"","doi":"10.1016/j.trgeo.2024.101413","DOIUrl":"10.1016/j.trgeo.2024.101413","url":null,"abstract":"<div><div>The soft clay under the road ground will suffer cyclic torsional shear stress encountered traffic load in addition to axial stress, which will cause further deformation of clay. To investigate the effect of torsional shear stress on the cumulative axial strain of clay, a series of undrained tests under cardioid stress path were performed on <em>K</em>₀ consolidated undisturbed samples by using a hollow cylinder apparatus (HCA). The effect of vertical cyclic stress ratio (<em>VCSR</em>) and shear stress ratio (<em>η</em>) on the deformation and degradation characteristics of clay was investigated. The results indicate that there is inconsistency between the strain path and stress path. The increase in <em>η</em> further accelerates the accumulation of axial strain, which resulted from the degradation of clay induced by torsional shear stress. Considering the <em>VCSR</em> and <em>η</em>, a calculation method of degradation index was developed. Furthermore, a cumulative axial strain prediction model of clay under the cardioid stress path was established considering the degradation. This model addresses the limitation of traditional prediction models by considering the impact of torsional shear stress on cumulative axial strain.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554140","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":"Explainable machine learning-based prediction model for dynamic resilient modulus of subgrade soils","authors":"","doi":"10.1016/j.trgeo.2024.101415","DOIUrl":"10.1016/j.trgeo.2024.101415","url":null,"abstract":"<div><div>The dynamic resilient modulus (<em>M_R</em>) of a subgrade soil is a fundamental parameter for evaluating the dynamic stability and service resilience of subgrade fillers and structures, as well as an instrumental input for calculating the mechanical response and fatigue life of a pavement structure. To accurately and reasonably characterise the <em>M_R</em> of subgrade soils, machine learning (ML) models were established using the support vector machine, random forest, and extreme gradient boosting algorithms based on a large-scale dataset including 3533 records of <em>M_R</em> tests conducted on subgrade soils. Meanwhile, the weighted<!--> <!-->plasticity index (WPI), initial moisture content (<em>w</em>), dry unit weight (γ<em>_d</em>), confining stress (<em>σ</em>_c), deviator stress (<em>σ</em>_d), and numbers of freeze–thaw cycles (<em>N_FT</em>) were set as the input variables to predict the <em>M_R</em> using ML models, which considered the effects of wheel loads, physical properties and climate fluctuation on the subgrade soils during the service period. Subsequently, the Shapley additive explanations method was developed to explain the prediction model for the <em>M_R</em> of subgrade soils based on ML algorithms. The results quantitatively illustrated the explicit mapping relationship and internal influencing mechanism between the significant features of the influences and <em>M_R</em> of subgrade soils, which was consistent with prior experimental and physical cognition. In summary, the study findings provide meaningful guidelines for the structural design and life evaluation of pavement subgrade engineering.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572533","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 of the polyurethane foam injection technique for road maintenance applications","authors":"","doi":"10.1016/j.trgeo.2024.101411","DOIUrl":"10.1016/j.trgeo.2024.101411","url":null,"abstract":"<div><div>Road infrastructure plays an important role in strengthening transportation and driving the economic advancement of countries. However, the increasing traffic volume has accelerated road deterioration, particularly at critical points like bridge-road junctions. Traditional repair methods involving demolition and reconstruction lead to extended closures and high costs. This study explores the polyurethane (PU) foam injection technique as an alternative solution, which can reduce both repair time and costs. The research evaluates the application of PU foam in various road projects across Thailand, highlighting its ability to repair pavement surfaces and structures, even in severely damaged areas. Despite its advantages, the use of PU foam faces challenges due to a lack of standardized quality control. This paper proposes a set of working guidelines for PU foam injection, aimed at key stakeholders such as the Department of Highways, the Department of Rural Roads, and the Department of Local Administration. The findings underline the importance of establishing standardized methods to ensure the long-term effectiveness of PU foam in road maintenance. Future research should focus on refining these guidelines for diverse road conditions to support the sustainable development of national transportation infrastructure.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554138","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":"Effects of hexagonal boron nitride nanosheets on the biostabilization of recycled sands for geotechnical fill applications","authors":"","doi":"10.1016/j.trgeo.2024.101420","DOIUrl":"10.1016/j.trgeo.2024.101420","url":null,"abstract":"<div><div>Biostabilization techniques including plant enzyme induced calcite precipitation (EICP) and microbially induced calcite precipitation (MICP) represent promising and environmentally friendly methods for improving the engineering properties of recycled geomaterials for geotechnical fill applications. In this study, hexagonal boron nitride (h-BN) nanosheets were dispersed and utilized as nano-additives in the EICP and MICP reaction processes to facilitate the precipitation of calcium carbonate polymorphs (CaCO₃) in washed recycled sands (RS) derived from construction and demolition (C&amp;D) wastes for geotechnical fill applications. The investigation comprised a systematic range of biological and chemical microscopic and macroscopic experiments intending to stabilize the RS for geotechnical fill applications. The study results suggested that using h-BN nanosheets did not have a notable impact on bacterial growth or the functioning of bacterial and plant enzyme activity. In addition, it was observed that the optimal addition of h-BN nanosheet additives substantially increased CaCO₃ precipitation by up to 34 % and 28 % in the EICP and MICP reaction processes respectively, which can be postulated to be due to the nanosheets acting as nucleation sites throughout the high surface area and negatively surface charge. Furthermore, the introduction of h-BN nanosheets led to a significant enhancement in the performance of unconfined compressive strength (UCS) of the stabilized RS through nanofillers and reinforcements, with improvements of up to 20 % and 13 % in the biostabilization of RS using the EICP and MICP after 10 treatment cycles. Detailed analyses, including Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) imaging, revealed that h-BN nanosheets, with a substantial surface area and effective chemical functional groups, interconnected with the CaCO₃ mineral surface. Overall, the study suggests that integrating effective additives can improve the utilization of EICP and MICP in geotechnical fill applications, namely in road embankments and pavements, whilst providing both commercial viability and enhanced performance.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142560940","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}

{"title":"Exploring liquefaction resistance in saturated and gassy sands at different state parameters","authors":"","doi":"10.1016/j.trgeo.2024.101410","DOIUrl":"10.1016/j.trgeo.2024.101410","url":null,"abstract":"<div><div>Earthquake-induced liquefaction is a relevant natural hazard due to the damages caused in numerous buildings, facilities and infrastructures worldwide. The damages caused to the infrastructure by this phenomenon are caused by the loss of stiffness and strength in granular soils, which leads to settlements and lateral spreading. Earthquake-induced liquefaction typically occurs in saturated deposits composed of non-plastic soils. Hence, the degree of saturation reduction is considered one of the most favourable and optimistic methods for liquefaction resistance mitigation. This paper explores the earthquake-induced liquefaction in saturated and gassy sands, varying their degree of saturation and state parameters. The state parameter was used to analyse the mechanical behaviour by combining the effects of relative density (or initial void ratio) with confinement pressure. Results show that liquefaction resistance improvement caused by the reduction in the degree of saturation is higher as the state parameter increases. This improvement can be described and quantified by multivariate models integrating the effects of degree of saturation and state parameter on liquefaction resistance. This provides a potential solution for improving the resilience of infrastructures susceptible to earthquake-induced liquefaction.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554137","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":"Deformation characteristics of root-reinforced soil under traffic induced cyclic loading","authors":"","doi":"10.1016/j.trgeo.2024.101424","DOIUrl":"10.1016/j.trgeo.2024.101424","url":null,"abstract":"<div><div>The slopes adjacent to highways and railroads, which are subjected to both static loads and dynamic loads induced by vehicles and trains, undergo mechanical stresses of varying magnitudes. As long-term cyclic loading can weaken the soil strength and generate excessive deformation, it is necessary to investigate the influence of root distribution on the deformation characteristics of soil reinforced by roots under cyclic loading. With a special focus on the soil stress state, dynamic triaxial tests were conducted to investigate the deformation characteristics induced by cyclic loading, accounting for loading frequency, dynamic stress amplitude and root distribution attributes. The results demonstrate that the crossed arrangement outperforms other patterns under dynamic loads. Root crossed arrangement reduces the plastic deformation of the soil by 70% to 80% and the resilient deformation by 30% to 40%. The soil transient deformation resistance is significantly enhanced through root arrangement, while root cross arrangement leads to a remarkable improvement in the soil dynamic modulus and damping ratio by approximately 200%. The confirmation was obtained that the Hardin and Drnevich hyperbolic model exhibited exceptional conformity and could be effectively employed in analyzing root-reinforced soil.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572534","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":"Mechanical response of buried water pipes to traffic loading before and after extreme cold waves","authors":"","doi":"10.1016/j.trgeo.2024.101418","DOIUrl":"10.1016/j.trgeo.2024.101418","url":null,"abstract":"<div><div>In recent years, the escalating frequency and intensity of extreme weather events like cold waves have heightened concerns regarding their impact on buried water pipelines, posing notable challenges to urban safety. These pipelines are particularly vulnerable to damage from the extreme low temperatures induced by cold waves, which can lead to significant system failures. This paper investigates the mechanical response of buried water pipelines to traffic loading before and after a cold wave using the Finite Element Method (FEM). Initially, a 3D numerical model was created to simulate the temperature distribution in the soil and buried pipe, utilizing field monitoring data gathered during a cold wave event at Shanghai city of Eastern China. Subsequently, a mechanical analysis of the soil-pipe model was conducted, employing the validated soil and pipe temperature field as predefined fields. The effects of temperature change rate, traffic load type, load position, and burial depth on the pipeline behavior are discussed in detail. The results demonstrated that cold waves significantly impact pipeline stress, an effect that is intensified by increased traffic loads. The peak Mises stress increased by up to 21 % for the 1.0 MPa load, underscoring the role of cold waves in amplifying pipeline stress. Moreover, while cold waves increase pipeline stress and vertical displacement, accelerating the rate of temperature change induced by the cold wave reduces the stress. Traffic load exerts the most significant impact at the bell and spigot joints, with effects remaining consistent regardless of joint position. Shallow-buried pipelines experience more pronounced stress changes in the presence of cold waves and traffic load, with stress increasing by 66.8 % at a depth of 1.5 m. This study demonstrates that the bell and spigot joints of shallow-buried pipes are highly susceptible to cold wave effects, especially under traffic loading, necessitating special attention to this potential failure location during such conditions.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554139","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":"Developing a real-time compaction quality assessment methodology for subgrade based on semi-supervised co-training","authors":"","doi":"10.1016/j.trgeo.2024.101412","DOIUrl":"10.1016/j.trgeo.2024.101412","url":null,"abstract":"<div><div>The current intelligent methodologies for real-time evaluation of subgrade compaction quality predominantly rely on supervised machine learning algorithms. However, the scarcity of sand cone test significantly impedes model performance, thereby severely limiting the applicability of intelligent subgrade compaction. This paper proposes a semi-supervised co-training algorithm for real-time evaluation of subgrade compactness during the construction procedure, leveraging unlabeled data to enhance the model performance. Based on the compaction datasets from various subgrade scenarios, the proposed PSO-XGB-Co-training KNN-PLS (PSO-XGB-CoKP) algorithm is utilized to train the unlabeled data, boasting a 20.4% reduction in Mean Squared Error (MSE). The semi-supervised co-training algorithm is modified by employing different regressors as co-trained sub-models and increasing the number of regressors. The model is optimized by levering the accuracy and computational cost, and an optimal data augmentation volume is recommended through the sensitivity study. This study provides an alternative approach for leveraging unbalanced and small-sample datasets to develop a reliable intelligent methodology for evaluating subgrade compaction quality in engineering practice.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538693","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":"Super-large diameter slurry shield tunnel encountering boulder formation: Detection, treatment and data analysis","authors":"","doi":"10.1016/j.trgeo.2024.101408","DOIUrl":"10.1016/j.trgeo.2024.101408","url":null,"abstract":"<div><div>Boulders pose substantial challenges in coastal urban tunnel engineering. This study, for the first time, utilizes extensive closely spaced borehole data from 3486 drilling points obtained during actual tunnelling through boulder strata to evaluate the effectiveness of microtremor detection, analyze variations in operational parameters, and assess the efficiency of blasting treatment. Additionally, leveraging borehole data, a 3D reconstruction of the soil-boulder-bedrock stratum was developed, and the stratum content ratio at the excavation face was derived. A multivariate linear regression model was established to explore the relationship between boulder geology and construction parameters. The results demonstrated that microtremor surveys effectively identified boulder distributions by analyzing horizontal-to-vertical spectral ratio curves and differences in surface wave phase velocity. Field drilling confirmed the high accuracy of microtremor predictions, particularly in areas with dense or thick boulder layers. Post-blasting secondary drilling revealed boulder fragments smaller than 30 cm, meeting the operational requirements for shield cutter and crusher systems. The presence of boulders was found to increase thrust, torque, and overturning moments, as well as cause abnormal cutter wear. Blasting significantly reduced the standard deviation of operational data, demonstrating its effectiveness in stabilizing tunnelling performance. Regression analysis showed a strong correlation between geological conditions and tunnelling parameters, with results indicating that blasting operations effectively mitigate the adverse impacts of boulders on shield tunnelling performance. This study aims to provide valuable insights and references for future engineering projects encountering similar complex geological conditions.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532860","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}