As compensation for the limited experimental data from the borehole logs, geological knowledge is expected to contribute to better risk assessment of the river levee system. Although natural levees have long been recognized as related to the underseepage risk of river levees, limited quantitative knowledge of hydraulic characteristics is available. Field surveys are conducted at a site along the Kokai River in Japan to reveal the hydraulic characteristics of natural levee sediments. Sounding tests allow us to capture laminar structures in the natural levee sediments. Through in-situ seepage tests, it is found that the silty materials in the natural levee sediments have hydraulic conductivity in the order of around E-06 m/s. Based on the results from the field surveys, numerical spatial hydraulic conductivity models of natural levees are built by applying geostatistical methods, including indicator Kriging and indicator simulations. The methodology in this study shows a possibility of quantifying geological knowledge, which finally contributes to the quantitative risk assessment against underseepage and internal erosion.
{"title":"Study on the hydraulic characteristics of natural levees by field surveys: Case study of the Kokai River, Japan","authors":"Wenyue Zhang , Mai Tabuchi , Tomotaka Yoshikawa , Akihiro Takahashi","doi":"10.1016/j.sandf.2025.101679","DOIUrl":"10.1016/j.sandf.2025.101679","url":null,"abstract":"<div><div>As compensation for the limited experimental data from the borehole logs, geological knowledge is expected to contribute to better risk assessment of the river levee system. Although natural levees have long been recognized as related to the underseepage risk of river levees, limited quantitative knowledge of hydraulic characteristics is available. Field surveys are conducted at a site along the Kokai River in Japan to reveal the hydraulic characteristics of natural levee sediments. Sounding tests allow us to capture laminar structures in the natural levee sediments. Through in-situ seepage tests, it is found that the silty materials in the natural levee sediments have hydraulic conductivity in the order of around E-06 m/s. Based on the results from the field surveys, numerical spatial hydraulic conductivity models of natural levees are built by applying geostatistical methods, including indicator Kriging and indicator simulations. The methodology in this study shows a possibility of quantifying geological knowledge, which finally contributes to the quantitative risk assessment against underseepage and internal erosion.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101679"},"PeriodicalIF":3.3,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144933048","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}
Pub Date : 2025-09-01DOI: 10.1016/j.sandf.2025.101683
Boxin Wang , Zihao Wang , Wen Zhang , Jingjing Pan , Jiaqi Liu , Qing Wang
The shear phenomenon between soil and foundation structure is common in foundation engineering. The change in the water content of stratum affects the shear behavior of soil and structure inevitably, especially in the region of cohesive soil with complex hydro-physical properties. In this paper, the silty clay in the Songnen Plain was used as a case study to reveal the shear failure mechanism of silty clay–structure interface under different water contents from multiple scales. First, the macroscopic mechanical characteristics were investigated by direct shear test and particle-image-velocimetry technology. To further explore the mesoscopic evolution law, this study proposed a novel FDM-DMDEM (Finite Difference Method–Determining Meso-parameter Discrete Element Method). This method enables direct calculation and assignment of meso-parameters required for the numerical model based on unsaturated soil theory, completely circumventing the laborious and subjective inverse calibration process inherent in conventional DEM. In this study, a 3D numerical model was established by using this coupling method and a parametric analysis was carried out. The results demonstrated that the meso-structure failure of silty clay within a certain range from the interface produced plastic deformation to form shear bands. Failure has two forms, namely, shear failure inside the shear band and shear failure outside the shear band. The increase in water content weakened the bonding force between particles, so that developing shear stress outside the shear band was difficult, resulting in typical shear failure inside the shear band. These findings could provide certain design references for the construction of foundation engineering in the Songnen Plain area.
{"title":"Experimental and numerical simulation for shear failure mechanism of silty clay–structure interface","authors":"Boxin Wang , Zihao Wang , Wen Zhang , Jingjing Pan , Jiaqi Liu , Qing Wang","doi":"10.1016/j.sandf.2025.101683","DOIUrl":"10.1016/j.sandf.2025.101683","url":null,"abstract":"<div><div>The shear phenomenon between soil and foundation structure is common in foundation engineering. The change in the water content of stratum affects the shear behavior of soil and structure inevitably, especially in the region of cohesive soil with complex hydro-physical properties. In this paper, the silty clay in the Songnen Plain was used as a case study to reveal the shear failure mechanism of silty clay–structure interface under different water contents from multiple scales. First, the macroscopic mechanical characteristics were investigated by direct shear test and particle-image-velocimetry technology. To further explore the mesoscopic evolution law, this study proposed a novel FDM-DMDEM (Finite Difference Method–Determining Meso-parameter Discrete Element Method). This method enables direct calculation and assignment of meso-parameters required for the numerical model based on unsaturated soil theory, completely circumventing the laborious and subjective inverse calibration process inherent in conventional DEM. In this study, a 3D numerical model was established by using this coupling method and a parametric analysis was carried out. The results demonstrated that the meso-structure failure of silty clay within a certain range from the interface produced plastic deformation to form shear bands. Failure has two forms, namely, shear failure inside the shear band and shear failure outside the shear band. The increase in water content weakened the bonding force between particles, so that developing shear stress outside the shear band was difficult, resulting in typical shear failure inside the shear band. These findings could provide certain design references for the construction of foundation engineering in the Songnen Plain area.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101683"},"PeriodicalIF":3.3,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003913","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}
Pub Date : 2025-08-29DOI: 10.1016/j.sandf.2025.101678
Jingwei Zhang , Zhencai Luo , Yunlong Liu , Bowen Zheng , Zhenguo Hou , Jin Kong
Due to merits of low noise and vibration, the pre-bored planted method has been widely used in engineering practice to assist the installation of the prestressed high-strength concrete (PHC) piles in area where deep and thick sand layers are commonly encountered. However, the research on the influence mechanism of pile driving methods in hard soil layers mainly focuses on the static pressing method and the hammering method, while the penetration characteristics under pre-bored assistance remains unclear. Therefore, a full-scale field test was conducted to investigate the installation effects. The penetration mechanisms of the piles with pre-bored assistance in areas with a deep and thick sand layer was discussed. Besides, an analytical method was proposed to predict the energy (hammer blow counts) necessary to drive pile to design depth. The results showed that the pre-bored grouted planted method significantly reduced the energy required for pile driving, compared to both the hammering method and the pre-bored planted method. This was because pre-drilling reduced displaced soil volume and relieved lateral stress. The pile load transfer mechanism was optimized by pre-drilling, which effectively leveraged the high compressive strength of the deep and thick sand layers. Meanwhile, the shaft friction within the grouted depth was significantly enhanced by the permeation, cementation and reinforcement effects of the concrete slurry, thereby improving the pile bearing capacity. Furthermore, the analytical method proposed based on the cavity expansion theory was capable of predicting the energy required for pile driving, which could guide the selection of pile driving equipment with minimum energy consumption and prevent pile damage caused by excessive hammering.
{"title":"In-situ investigation on installation mechanisms of pre-bored grouted planted piles in deep and thick sand layers","authors":"Jingwei Zhang , Zhencai Luo , Yunlong Liu , Bowen Zheng , Zhenguo Hou , Jin Kong","doi":"10.1016/j.sandf.2025.101678","DOIUrl":"10.1016/j.sandf.2025.101678","url":null,"abstract":"<div><div>Due to merits of low noise and vibration, the pre-bored planted method has been widely used in engineering practice to assist the installation of the prestressed high-strength concrete (PHC) piles in area where deep and thick sand layers are commonly encountered. However, the research on the influence mechanism of pile driving methods in hard soil layers mainly focuses on the static pressing method and the hammering method, while the penetration characteristics under pre-bored assistance remains unclear. Therefore, a full-scale field test was conducted to investigate the installation effects. The penetration mechanisms of the piles with pre-bored assistance in areas with a deep and thick sand layer was discussed. Besides, an analytical method was proposed to predict the energy (hammer blow counts) necessary to drive pile to design depth. The results showed that the pre-bored grouted planted method significantly reduced the energy required for pile driving, compared to both the hammering method and the pre-bored planted method. This was because pre-drilling reduced displaced soil volume and relieved lateral stress. The pile load transfer mechanism was optimized by pre-drilling, which effectively leveraged the high compressive strength of the deep and thick sand layers. Meanwhile, the shaft friction within the grouted depth was significantly enhanced by the permeation, cementation and reinforcement effects of the concrete slurry, thereby improving the pile bearing capacity. Furthermore, the analytical method proposed based on the cavity expansion theory was capable of predicting the energy required for pile driving, which could guide the selection of pile driving equipment with minimum energy consumption and prevent pile damage caused by excessive hammering.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101678"},"PeriodicalIF":3.3,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144917494","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}
Pub Date : 2025-08-26DOI: 10.1016/j.sandf.2025.101675
Bin Zhuo, Yong Fang, Liupan Dou, Xuedan Liu, Muyuan Zhu, Xiongyu Hu
When an earth pressure balance shield machine is tunneling in cohesive soils, a poorly effective soil conditioning scheme often leads to clogging in the cutterhead and the screw conveyor, which reduces tunneling efficiency and may even cause the shield machine to stop tunneling. Different from the conventional test method that use artificial clay soil, this study relies on the field shield engineering in mudstone strata and conducts soil conditioning tests using the field soil as the basic material. Using a shield soil migration model test, the whole process of clogging in a screw conveyor is reproduced, and the pattern of migration change of soil in the screw conveyor is obtained. The screw conveyor torque decreases with the increase of foam injection rate. When the slump of soil reaches 15 cm, the torque tends to be stable. Based on this, this study innovatively establishes a theoretical calculation model that can quantitatively describe the relationship between the soil discharge and the pressure gradient. Experimental verification shows that this model can not only quantitatively describe the variation laws of the soil discharge and the pressure gradient, but also qualitatively reveal the influence mechanism of the soil chamber pressure and soil fluidity on the discharge efficiency. Finally, using the Ziyang line of the Chengdu rail transit as a field test, it is found that under the recommended soil conditioning scheme, the clogging problem in the shield cutterhead and screw conveyor is greatly reduced and the efficiency of shield tunneling is significantly improved.
{"title":"An experimental and theoretical research on shield screw conveyor discharging efficiency in moderately weathered mudstone strata and its influence on clogging","authors":"Bin Zhuo, Yong Fang, Liupan Dou, Xuedan Liu, Muyuan Zhu, Xiongyu Hu","doi":"10.1016/j.sandf.2025.101675","DOIUrl":"10.1016/j.sandf.2025.101675","url":null,"abstract":"<div><div>When an earth pressure balance shield machine is tunneling in cohesive soils, a poorly effective soil conditioning scheme often leads to clogging in the cutterhead and the screw conveyor, which reduces tunneling efficiency and may even cause the shield machine to stop tunneling. Different from the conventional test method that use artificial clay soil, this study relies on the field shield engineering in mudstone strata and conducts soil conditioning tests using the field soil as the basic material. Using a shield soil migration model test, the whole process of clogging in a screw conveyor is reproduced, and the pattern of migration change of soil in the screw conveyor is obtained. The screw conveyor torque decreases with the increase of foam injection rate. When the slump of soil reaches 15 cm, the torque tends to be stable. Based on this, this study innovatively establishes a theoretical calculation model that can quantitatively describe the relationship between the soil discharge and the pressure gradient. Experimental verification shows that this model can not only quantitatively describe the variation laws of the soil discharge and the pressure gradient, but also qualitatively reveal the influence mechanism of the soil chamber pressure and soil fluidity on the discharge efficiency. Finally, using the Ziyang line of the Chengdu rail transit as a field test, it is found that under the recommended soil conditioning scheme, the clogging problem in the shield cutterhead and screw conveyor is greatly reduced and the efficiency of shield tunneling is significantly improved.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101675"},"PeriodicalIF":3.3,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144896096","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}
Pub Date : 2025-08-26DOI: 10.1016/j.sandf.2025.101681
Yao Xiao , Qiuyan Lin , Wenyue Fang , Rui Zhang
This paper employs an adaptive finite element limit analysis (AFELA) combined with nonlinear programming (NLP) to investigate the seismic bearing capacity of strip footings overlying cavities in rock masses that obey the generalized Hoek–Brown (GHB) failure criterion. The feasible arc interior point algorithm (FAIPA) is utilized to solve the optimization models, and a novel imprecise step search algorithm is introduced to improve the NLP convergence. Based on the self-developed AFELA procedure, the bearing capacity reduction factor R of strip footing on a rock mass has been calculated, with the results presented in tables and charts. Parametric analysis reveals that a footing centered above a cavity does not exhibit the lowest capacity, likely due to a beneficial arching effect. Failure modes associated with varying parameters are also discussed, and the results show that increasing the horizontal seismic coefficient reduces the extent of the failure zone.
{"title":"Seismic bearing capacity of strip footing above cavities in rock masses","authors":"Yao Xiao , Qiuyan Lin , Wenyue Fang , Rui Zhang","doi":"10.1016/j.sandf.2025.101681","DOIUrl":"10.1016/j.sandf.2025.101681","url":null,"abstract":"<div><div>This paper employs an adaptive finite element limit analysis (AFELA) combined with nonlinear programming (NLP) to investigate the seismic bearing capacity of strip footings overlying cavities in rock masses that obey the generalized Hoek–Brown (GHB) failure criterion. The feasible arc interior point algorithm (FAIPA) is utilized to solve the optimization models, and a novel imprecise step search algorithm is introduced to improve the NLP convergence. Based on the self-developed AFELA procedure, the bearing capacity reduction factor <em>R</em> of strip footing on a rock mass has been calculated, with the results presented in tables and charts. Parametric analysis reveals that a footing centered above a cavity does not exhibit the lowest capacity, likely due to a beneficial arching effect. Failure modes associated with varying parameters are also discussed, and the results show that increasing the horizontal seismic coefficient reduces the extent of the failure zone.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101681"},"PeriodicalIF":3.3,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144904645","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}
Pub Date : 2025-08-22DOI: 10.1016/j.sandf.2025.101680
Yongping Li , Songzhao Qu , Jing Bai , Dongming Yang , Sangtian Hu , Lefu Di , Ruiyuan Han , Yijin Wu , Yuan Xiang , Dapeng Wang , Yi Zhang , Yonghua Guo , Zhe Zhang
In aeolian sand, the mechanical behavior of helical anchors involves complex performance evolution mechanisms that are not yet fully understood. This study employs a multi-scale integrated approach combining field tests, numerical simulations, and machine learning to systematically investigate the evolution laws of the bearing behavior of helical anchors. The results indicate: (1) The critical embedment depth threshold for helical anchors in aeolian sand is H = 5D; beyond this threshold, the load direction effect can be neglected. (2) Multi-plate helical anchors exhibit significant geometrically nonlinear superposition behavior. Dense spacing (S/D < 4) produces notable stress superposition effects (η = 1.15–1.32), whereas wide spacing (S/D ≥ 4) results in independent bearing units (η = 0.97–1.03). (3) The XGBoost machine learning model identifies the internal friction angle, anchor plate diameter, and embedment depth ratio as the most influential features affecting bearing capacity. Based on these control parameters, predictive equations for the bearing capacity coefficient Nq and soil lateral friction coefficient Ku were developed, with predictions showing excellent agreement with experimental data. This provides engineers with a reliable analytical framework for performance-based design. The study not only deepens the understanding of the behavioral mechanisms of helical piles in aeolian sand but also offers practical solutions for geotechnical engineering practice.
{"title":"Experimental and numerical study on helical piles in aeolian sand: bearing behavior and design methods","authors":"Yongping Li , Songzhao Qu , Jing Bai , Dongming Yang , Sangtian Hu , Lefu Di , Ruiyuan Han , Yijin Wu , Yuan Xiang , Dapeng Wang , Yi Zhang , Yonghua Guo , Zhe Zhang","doi":"10.1016/j.sandf.2025.101680","DOIUrl":"10.1016/j.sandf.2025.101680","url":null,"abstract":"<div><div>In aeolian sand, the mechanical behavior of helical anchors involves complex performance evolution mechanisms that are not yet fully understood. This study employs a multi-scale integrated approach combining field tests, numerical simulations, and machine learning to systematically investigate the evolution laws of the bearing behavior of helical anchors. The results indicate: (1) The critical embedment depth threshold for helical anchors in aeolian sand is <em>H</em> = 5<em>D</em>; beyond this threshold, the load direction effect can be neglected. (2) Multi-plate helical anchors exhibit significant geometrically nonlinear superposition behavior. Dense spacing (<em>S</em>/<em>D</em> < 4) produces notable stress superposition effects (<em>η</em> = 1.15–1.32), whereas wide spacing (<em>S</em>/<em>D</em> ≥ 4) results in independent bearing units (<em>η</em> = 0.97–1.03). (3) The XGBoost machine learning model identifies the internal friction angle, anchor plate diameter, and embedment depth ratio as the most influential features affecting bearing capacity. Based on these control parameters, predictive equations for the bearing capacity coefficient <em>N</em><sub>q</sub> and soil lateral friction coefficient <em>K</em><sub>u</sub> were developed, with predictions showing excellent agreement with experimental data. This provides engineers with a reliable analytical framework for performance-based design. The study not only deepens the understanding of the behavioral mechanisms of helical piles in aeolian sand but also offers practical solutions for geotechnical engineering practice.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101680"},"PeriodicalIF":3.3,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889475","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}
Pub Date : 2025-08-22DOI: 10.1016/j.sandf.2025.101677
Riwaj Dhakal, Misko Cubrinovski
One-dimensional (1D) dynamic effective stress site response analysis (ESA) is performed for profiles at the port of Wellington, New Zealand (CentrePort), which contains reclamation fills comprised of gravel-sand-silt (G-S-S) mixtures and hydraulic fills. The first phase of the study realistically simulates three recent earthquake case histories while considering modelling uncertainties by using the PM4Sand and the Stress-Density constitutive models. The results illustrate possible mechanisms explaining the severity of liquefaction manifestation and soil ejecta characteristics observed in G-S-S fills through careful engineering interpretation of the response. Challenges for 1D ESA to explain complex manifestation patterns affected by two-dimensional variability in fill composition and response characteristics are illustrated for the hydraulic fills. In the second phase of analyses, ESA-based response measures are proposed to quantify the severity of the liquefaction response for a range of input seismic demands. The response characteristics show very small scatter despite using a range of different input ground motions and two soil constitutive models. Results illustrate the capability of ESA to capture details of the liquefaction response such as the similar threshold seismic intensity for liquefaction triggering of the loosely deposited fills, different maximum response of the sites reflecting the differences in the thicknesses of the fills, and the evolution of the response from triggering to maximum reflecting differences in depositional characteristics.
{"title":"Liquefaction response of reclaimed soils from effective stress analysis","authors":"Riwaj Dhakal, Misko Cubrinovski","doi":"10.1016/j.sandf.2025.101677","DOIUrl":"10.1016/j.sandf.2025.101677","url":null,"abstract":"<div><div>One-dimensional (1D) dynamic effective stress site response analysis (ESA) is performed for profiles at the port of Wellington, New Zealand (CentrePort), which contains reclamation fills comprised of gravel-sand-silt (G-S-S) mixtures and hydraulic fills. The first phase of the study realistically simulates three recent earthquake case histories while considering modelling uncertainties by using the PM4Sand and the Stress-Density constitutive models. The results illustrate possible mechanisms explaining the severity of liquefaction manifestation and soil ejecta characteristics observed in G-S-S fills through careful engineering interpretation of the response. Challenges for 1D ESA to explain complex manifestation patterns affected by two-dimensional variability in fill composition and response characteristics are illustrated for the hydraulic fills. In the second phase of analyses, ESA-based response measures are proposed to quantify the severity of the liquefaction response for a range of input seismic demands. The response characteristics show very small scatter despite using a range of different input ground motions and two soil constitutive models. Results illustrate the capability of ESA to capture details of the liquefaction response such as the similar threshold seismic intensity for liquefaction triggering of the loosely deposited fills, different maximum response of the sites reflecting the differences in the thicknesses of the fills, and the evolution of the response from triggering to maximum reflecting differences in depositional characteristics.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101677"},"PeriodicalIF":3.3,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889476","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}
Pub Date : 2025-08-22DOI: 10.1016/j.sandf.2025.101676
Pierluigi Alesiani , Paolo Ruggeri , Viviene M.E. Fruzzetti , Giuseppe Scarpelli
Evaluating the seismic performance of retaining walls is a significant engineering challenge due to non-linear soil-structure interaction, site response effects and ground motion properties. State of the art methods, based on non-linear dynamic analysis, are nowadays able to give reliable results when the numerical modeling is carried out with careful evaluation of seismic signals and appropriate choice of constitutive relationship for soils. However, a similar analysis is mostly restricted to relevant infrastructures. For large part of the practical situations, the simplified seismic analysis still represents the most used tool for design and verification. The new generation of Eurocode in Europe has introduced some innovations on the use of simplified seismic analyses making them more rationale and site-specific. In this paper, a case study involving the seismic evaluation of an existing anchored sheet-pile quay wall in the Ravenna port is presented. A well-known geotechnical setting and the data from an extensive field and laboratory investigation available for the area, allowed to perform both simplified and non-linear dynamic seismic analyses. The simplified seismic analysis according to the pseudo-static method outlined in the new draft of Eurocode 8 (FprEN1998:2024 TC250 – part 1 and 5), has been carried out and compared with the seismic performance of the quay wall evaluated through a 2D FEM non-linear dynamic analysis. Also, the seismic displacements of the quay wall from 2D FEM non-linear dynamic analysis were compared with recently proposed Newmark-type simplified methods. Relevant aspects of the presented case study are the very deep location of the bedrock, which required a separate model for site response analysis and 2D FEM non-linear dynamic analysis of the structures and the significant length of the wall embedment, due to poor geotechnical properties of the ground, which resulted in a pronounced spatial variation with depth of the ground motion.
由于非线性土-结构相互作用、场地反应效应和地震动特性，评估挡土墙的抗震性能是一项重大的工程挑战。目前，基于非线性动力分析的方法，在对地震信号进行仔细评估和适当选择土的本构关系的情况下进行数值模拟，能够给出可靠的结果。然而，类似的分析主要局限于相关的基础设施。在大部分实际情况下，简化地震分析仍然是最常用的设计和验证工具。欧洲新一代的欧洲规范在简化地震分析的使用上引入了一些创新，使它们更加合理和具体。本文介绍了拉文纳港现有锚固板桩码头墙的地震评价实例。众所周知，该地区的地质技术背景和广泛的现场和实验室调查数据，允许进行简化和非线性动态地震分析。根据欧洲规范8新草案（FprEN1998:2024 TC250 - part 1和part 5）中概述的拟静力法进行了简化的地震分析，并与通过二维有限元非线性动力分析评估的码头墙抗震性能进行了比较。同时，将二维有限元非线性动力分析得到的码头墙体地震位移与近期提出的newmark型简化方法进行了比较。所提出的案例研究的相关方面是基岩的非常深的位置，这需要一个单独的模型进行现场响应分析和二维有限元非线性动力分析的结构和墙体嵌入的显著长度，由于地面的岩土性能差，导致地面运动的深度明显的空间变化。
{"title":"Seismic performance of an existing anchored quay wall in the Ravenna port (Italy)","authors":"Pierluigi Alesiani , Paolo Ruggeri , Viviene M.E. Fruzzetti , Giuseppe Scarpelli","doi":"10.1016/j.sandf.2025.101676","DOIUrl":"10.1016/j.sandf.2025.101676","url":null,"abstract":"<div><div>Evaluating the seismic performance of retaining walls is a significant engineering challenge due to non-linear soil-structure interaction, site response effects and ground motion properties. State of the art methods, based on non-linear dynamic analysis, are nowadays able to give reliable results when the numerical modeling is carried out with careful evaluation of seismic signals and appropriate choice of constitutive relationship for soils. However, a similar analysis is mostly restricted to relevant infrastructures. For large part of the practical situations, the simplified seismic analysis still represents the most used tool for design and verification. The new generation of Eurocode in Europe has introduced some innovations on the use of simplified seismic analyses making them more rationale and site-specific. In this paper, a case study involving the seismic evaluation of an existing anchored sheet-pile quay wall in the Ravenna port is presented. A well-known geotechnical setting and the data from an extensive field and laboratory investigation available for the area, allowed to perform both simplified and non-linear dynamic seismic analyses. The simplified seismic analysis according to the pseudo-static method outlined in the new draft of Eurocode 8 (FprEN1998:2024 TC250 – part 1 and 5), has been carried out and compared with the seismic performance of the quay wall evaluated through a 2D FEM non-linear dynamic analysis. Also, the seismic displacements of the quay wall from 2D FEM non-linear dynamic analysis were compared with recently proposed Newmark-type simplified methods. Relevant aspects of the presented case study are the very deep location of the bedrock, which required a separate model for site response analysis and 2D FEM non-linear dynamic analysis of the structures and the significant length of the wall embedment, due to poor geotechnical properties of the ground, which resulted in a pronounced spatial variation with depth of the ground motion.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101676"},"PeriodicalIF":3.3,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889477","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}
Pub Date : 2025-08-12DOI: 10.1016/j.sandf.2025.101659
Osamu Otsuka , Mitsuo Yamashita
Selenium is a rare metal found mainly in volcanic sediments; it is naturally distributed in Japan owing to its sulfide deposits. Selenium exists in soil as highly toxic and soluble seleno-oxyanions, namely, selenate and selenite. The Japanese government has established standards for soluble selenium concentrations in soil, achieved by water shielding or the addition of insolubilization agents. If the selenium (and/or other heavy metals) in tunnel-excavated muck exceeds the environmental standards, it should be treated similarly to contaminated soil. However, conventional treatments leave selenium residues in tunnel-excavated muck, preventing their reuse due to the risk of selenium re-elution. This study attempted to insolubilize soluble seleno-oxyanions in tunnel-excavated muck by adding the bacterium Stutzerimonas stutzeri NT-I, which reduces selenate to insoluble elemental selenium and then to volatile dimethyl diselenide. Selenate reduction tests were conducted by adding heavy metals, including As(III), As(V), Cd(II), Pb(II), and Fe(III), to examine the selenate reduction ability and growth of S. stutzeri NT-I in the presence of their ions. The results showed that the S. stutzeri NT-I reduced the selenate by 50 mg/L concentrations for all the tested contaminants. In naturally contaminated tunnel-excavated muck, heavy metal elements, nitrate, and nitrite contents were detected at levels of <50 mg/L, suggesting that they do not adversely affect the selenate reduction by S. stutzeri NT-I. The results indicate that selenium insolubilization using S. stutzeri NT-I can be applied to a wide range of tunnel-excavated muck.
{"title":"Bioremediation for seleno-oxyanions in tunnel-excavated muck using selenate-reducing bacterium Stutzerimonas stutzeri NT-I","authors":"Osamu Otsuka , Mitsuo Yamashita","doi":"10.1016/j.sandf.2025.101659","DOIUrl":"10.1016/j.sandf.2025.101659","url":null,"abstract":"<div><div>Selenium is a rare metal found mainly in volcanic sediments; it is naturally distributed in Japan owing to its sulfide deposits. Selenium exists in soil as highly toxic and soluble seleno-oxyanions, namely, selenate and selenite. The Japanese government has established standards for soluble selenium concentrations in soil, achieved by water shielding or the addition of insolubilization agents. If the selenium (and/or other heavy metals) in tunnel-excavated muck exceeds the environmental standards, it should be treated similarly to contaminated soil. However, conventional treatments leave selenium residues in tunnel-excavated muck, preventing their reuse due to the risk of selenium re-elution. This study attempted to insolubilize soluble seleno-oxyanions in tunnel-excavated muck by adding the bacterium <em>Stutzerimonas stutzeri</em> NT-I, which reduces selenate to insoluble elemental selenium and then to volatile dimethyl diselenide. Selenate reduction tests were conducted by adding heavy metals, including As(III), As(V), Cd(II), Pb(II), and Fe(III), to examine the selenate reduction ability and growth of <em>S. stutzeri</em> NT-I in the presence of their ions. The results showed that the <em>S. stutzeri</em> NT-I reduced the selenate by 50 mg/L concentrations for all the tested contaminants. In naturally contaminated tunnel-excavated muck, heavy metal elements, nitrate, and nitrite contents were detected at levels of <50 mg/L, suggesting that they do not adversely affect the selenate reduction by <em>S</em>. <em>stutzeri</em> NT-I. The results indicate that selenium insolubilization using <em>S</em>. <em>stutzeri</em> NT-I can be applied to a wide range of tunnel-excavated muck.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101659"},"PeriodicalIF":3.3,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144831509","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}
Pub Date : 2025-08-12DOI: 10.1016/j.sandf.2025.101666
Zhangqing Xuan , Yanyan Cai , Jin Yu , Peng Xue
To investigate the stress–strain characteristics and particle breakage laws of coral sand under the rotation of the principal stress axis—Objectives, the triaxial test and the principal stress axis rotation test were conducted on coral sand with varying consolidation confining pressures and compactness—Methods. Furthermore, a particle breakage model considering the irregularity and non-uniformity inherent in coral sand was established. The results show that: (1) Scanning electron microscopy (SEM) analysis and triaxial test demonstrates that the coral sand has strong non-coaxial characteristics. Both increased compactness and confining pressure enhance the strength of coral sand; (2) Coral sand undergoes shear expansion followed by gradual compression in triaxial shear, and demonstrates body shrinkage when its compactness is relatively high. The broken particles of coral sand are mainly large particles, small particles are less broken or not broken, and the disappearance of prism is the main type of particle breakage; (3) The form of particle breakage in coral sand under rotation of the principal stress axis is mainly grinding—Key Findings. The irregularity and non-uniformity of coral sand can be represented with the equivalent of non-coaxiality in the deformation and breakage process of the principal stress axis rotation, and a mathematical model has been established to characterize the breakage behavior of coral sand particles. Impressively, The model demonstrates high accuracy in predicting particle breakage under principal stress rotation (average error < 5 %).
{"title":"Characteristics and modelling of coral sand particle breakage under principal stress axis rotation","authors":"Zhangqing Xuan , Yanyan Cai , Jin Yu , Peng Xue","doi":"10.1016/j.sandf.2025.101666","DOIUrl":"10.1016/j.sandf.2025.101666","url":null,"abstract":"<div><div>To investigate the stress–strain characteristics and particle breakage laws of coral sand under the rotation of the principal stress axis—Objectives, the triaxial test and the principal stress axis rotation test were conducted on coral sand with varying consolidation confining pressures and compactness—Methods. Furthermore, a particle breakage model considering the irregularity and non-uniformity inherent in coral sand was established. The results show that: (1) Scanning electron microscopy (SEM) analysis and triaxial test demonstrates that the coral sand has strong non-coaxial characteristics. Both increased compactness and confining pressure enhance the strength of coral sand; (2) Coral sand undergoes shear expansion followed by gradual compression in triaxial shear, and demonstrates body shrinkage when its compactness is relatively high. The broken particles of coral sand are mainly large particles, small particles are less broken or not broken, and the disappearance of prism is the main type of particle breakage; (3) The form of particle breakage in coral sand under rotation of the principal stress axis is mainly grinding—Key Findings. The irregularity and non-uniformity of coral sand can be represented with the equivalent of non-coaxiality in the deformation and breakage process of the principal stress axis rotation, and a mathematical model has been established to characterize the breakage behavior of coral sand particles. Impressively, The model demonstrates high accuracy in predicting particle breakage under principal stress rotation (average error < 5 %).</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 5","pages":"Article 101666"},"PeriodicalIF":3.3,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144831465","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}
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