Pub Date : 2025-06-01Epub Date: 2025-04-07DOI: 10.1016/j.sandf.2025.101612
Zhengyao He, Nicolas G.L.H. Lee, S.P. Gopal Madabhushi
With increased demand for urban space, there is a growing propensity to move urban lifeline systems such as Metro systems and utilities to shallow, cut-and-cover tunnels. The seismic behaviour of such rectangular tunnels is important as these systems need to remain operational in the period after the earthquake for emergency rescue & recovery operations. In this paper, the main focus will be on determining the seismic response of shallow, rectangular tunnels that are buried in loose dry or saturated sand layers, and clay layers with different undrained shear strengths. The results from four centrifuge testing campaigns will be presented. The dynamic responses of the tunnel and soil will be compared to the input motion. The tunnel movements and soil deformations during seismic loading were obtained using high-resolution, high-speed imaging in combination with GeoPIV-RG software. Finally, conclusions will be drawn on the effects of the soil strata through which the tunnel passes, based on these centrifuge data that simulate the most critical geological conditions.
{"title":"Seismic behaviour of shallow cut-and-cover tunnels","authors":"Zhengyao He, Nicolas G.L.H. Lee, S.P. Gopal Madabhushi","doi":"10.1016/j.sandf.2025.101612","DOIUrl":"10.1016/j.sandf.2025.101612","url":null,"abstract":"<div><div>With increased demand for urban space, there is a growing propensity to move urban lifeline systems such as Metro systems and utilities to shallow, cut-and-cover tunnels. The seismic behaviour of such rectangular tunnels is important as these systems need to remain operational in the period after the earthquake for emergency rescue & recovery operations. In this paper, the main focus will be on determining the seismic response of shallow, rectangular tunnels that are buried in loose dry or saturated sand layers, and clay layers with different undrained shear strengths. The results from four centrifuge testing campaigns will be presented. The dynamic responses of the tunnel and soil will be compared to the input motion. The tunnel movements and soil deformations during seismic loading were obtained using high-resolution, high-speed imaging in combination with GeoPIV-RG software. Finally, conclusions will be drawn on the effects of the soil strata through which the tunnel passes, based on these centrifuge data that simulate the most critical geological conditions.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101612"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143786031","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}
Pub Date : 2025-06-01Epub Date: 2025-06-05DOI: 10.1016/j.sandf.2025.101632
Hao Liu , Zongxiang Xiu , Lejun Liu , Jie Dong , Qiuhong Xie , Mu Huang , Chenwei Luo , Yifeng Zeng , Xingsen Guo
Studying the rheological properties of deep-sea shallow sediments can provide basic mechanical characteristics for designing deep-sea mining vehicles driving on the soft seabed, providing anchoring stability of semi-submersible mining platforms, and assessing submarine landslide hazards. Shallow sediment column samples from the Western Pacific mining area were obtained, and their rheological properties were studied. A series of rheological tests was conducted under different conditions using an RST rheometer. In addition, conventional physical property, mineral composition, and microstructure analyses were conducted. The results showed that shallow sediments have a high liquid limit and plasticity, with flocculent and honeycomb-like flaky structures as the main microstructure types. The rheological properties exhibited typical non-Newtonian fluid characteristics with yield stress and shear-thinning phenomena during the shearing process. In contrast to previous studies on deep-sea soft soil sediments, a remarkable long-range shear-softening stage, called the thixotropic fluid stage, was discovered in the overall rheological curve. A four-stage model is proposed for the transition mechanism of deep-sea shallow sediments from the solid to liquid–solid, solid–liquid transition, thixotropic fluid, and stable fluid stages. The mechanism of the newly added thixotropic fluid stage was quantitatively analyzed using a modified Cross rheological model, and this stage was inferred from the perspective of mineralogy and microstructure. The results of this study can be useful for improving the operational safety and work efficiency of submarine operation equipment for deep-sea mining in the Western Pacific Ocean.
{"title":"Rheological properties of deep-sea shallow sediments in the Western Pacific mining area","authors":"Hao Liu , Zongxiang Xiu , Lejun Liu , Jie Dong , Qiuhong Xie , Mu Huang , Chenwei Luo , Yifeng Zeng , Xingsen Guo","doi":"10.1016/j.sandf.2025.101632","DOIUrl":"10.1016/j.sandf.2025.101632","url":null,"abstract":"<div><div>Studying the rheological properties of deep-sea shallow sediments can provide basic mechanical characteristics for designing deep-sea mining vehicles driving on the soft seabed, providing anchoring stability of semi-submersible mining platforms, and assessing submarine landslide hazards. Shallow sediment column samples from the Western Pacific mining area were obtained, and their rheological properties were studied. A series of rheological tests was conducted under different conditions using an RST rheometer. In addition, conventional physical property, mineral composition, and microstructure analyses were conducted. The results showed that shallow sediments have a high liquid limit and plasticity, with flocculent and honeycomb-like flaky structures as the main microstructure types. The rheological properties exhibited typical non-Newtonian fluid characteristics with yield stress and shear-thinning phenomena during the shearing process. In contrast to previous studies on deep-sea soft soil sediments, a remarkable long-range shear-softening stage, called the thixotropic fluid stage, was discovered in the overall rheological curve. A four-stage model is proposed for the transition mechanism of deep-sea shallow sediments from the solid to liquid–solid, solid–liquid transition, thixotropic fluid, and stable fluid stages. The mechanism of the newly added thixotropic fluid stage was quantitatively analyzed using a modified Cross rheological model, and this stage was inferred from the perspective of mineralogy and microstructure. The results of this study can be useful for improving the operational safety and work efficiency of submarine operation equipment for deep-sea mining in the Western Pacific Ocean.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101632"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144221511","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 : 2025-06-01Epub Date: 2025-04-04DOI: 10.1016/j.sandf.2025.101616
Juan Du , Xingfei Jiang , Bingyang Liu , Tao Li , Ningjun Jiang
In Hainan Province, China, the unique geographical location presents significant challenges to the safety of coastal infrastructure due to complex dynamic loads such as waves, sea breeze and earthquake. A type of organic matter-rich and poorly graded organic-matter-disseminated sand (OMDS) is commonly found in this region. The existence of OMDS can reduce the bearing capacity of composite foundation and may even lead to structural failure. Currently, there is insufficient understanding regarding this type of sand. This article characterizes the dynamic parameters of OMDS through dynamic elastic modulus (Ed) and damping ratio (λ). A series of undrained cyclic triaxial shear tests were carried out on OMDS specimens with varying compaction energy, initial confining pressure and consolidation ratios. Based on these experiments, a modified Hardin-Drnevich model is presented to explain the dynamic constitutive relation. Furthermore, the impacts of compaction energy, initial confining pressure, and consolidation ratio on skeleton curve, Ed, normalized dynamic elastic modulus (Ed/Edmax) and λ are systematically discussed. The results show that dynamic axial stress (σd), Ed, Ed/Edmax and λ are all proportional to the compaction energy; lower compaction energy results in earlier stiffness deterioration. As confining pressure increases, σd and Ed rise, while λ decreases, with Ed /Edmax being less affected. Finally, empirical models with respect of the varied parameters are proposed to estimate the maximum dynamic elastic modulus (Edmax) and maximum damping ratio (λmax), yielding relatively accurate estimation results. This study provides new insights into the dynamic properties of bay facies sand enriched with organic matter, which may facilitate the design and application of this type of sand in coastal projects.
{"title":"Dynamic modulus and damping ratio of organic-matter-disseminated sand under cyclic triaxial condition","authors":"Juan Du , Xingfei Jiang , Bingyang Liu , Tao Li , Ningjun Jiang","doi":"10.1016/j.sandf.2025.101616","DOIUrl":"10.1016/j.sandf.2025.101616","url":null,"abstract":"<div><div>In Hainan Province, China, the unique geographical location presents significant challenges to the safety of coastal infrastructure due to complex dynamic loads such as waves, sea breeze and earthquake. A type of organic matter-rich and poorly graded organic-matter-disseminated sand (OMDS) is commonly found in this region. The existence of OMDS can reduce the bearing capacity of composite foundation and may even lead to structural failure. Currently, there is insufficient understanding regarding this type of sand. This article characterizes the dynamic parameters of OMDS through dynamic elastic modulus (<em>E</em><sub>d</sub>) and damping ratio (<em>λ</em>). A series of undrained cyclic triaxial shear tests were carried out on OMDS specimens with varying compaction energy, initial confining pressure and consolidation ratios. Based on these experiments, a modified Hardin-Drnevich model is presented to explain the dynamic constitutive relation. Furthermore, the impacts of compaction energy, initial confining pressure, and consolidation ratio on skeleton curve, <em>E</em><sub>d</sub>, normalized dynamic elastic modulus (<em>E</em><sub>d</sub>/<em>E</em><sub>dmax</sub>) and <em>λ</em> are systematically discussed. The results show that dynamic axial stress (<em>σ</em><sub>d</sub>), <em>E</em><sub>d</sub>, <em>E</em><sub>d</sub>/<em>E</em><sub>dmax</sub> and <em>λ</em> are all proportional to the compaction energy; lower compaction energy results in earlier stiffness deterioration. As confining pressure increases, <em>σ</em><sub>d</sub> and <em>E</em><sub>d</sub> rise, while <em>λ</em> decreases, with <em>E</em><sub>d</sub> /<em>E</em><sub>dmax</sub> being less affected. Finally, empirical models with respect of the varied parameters are proposed to estimate the maximum dynamic elastic modulus (<em>E</em><sub>dmax</sub>) and maximum damping ratio (<em>λ</em> <sub>max</sub>), yielding relatively accurate estimation results. This study provides new insights into the dynamic properties of bay facies sand enriched with organic matter, which may facilitate the design and application of this type of sand in coastal projects.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101616"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768190","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}
The Continuous Flight Auger (CFA) piles, also known as Auger Cast In Place piles (ACIP), have a widespread use in the world market of replacement concrete piles. The installation of such piles is generally made by equipment which records several significant installation parameters, as the torque Mt and the axial force N, applied during the auger advancing step. In the auger retrieval stage other parameters that can influence the load-settlement performance of the pile are monitored. The paper presents a case study dealing with the CFA piles adopted as a foundation for a water treatment basin. In the paper first the equations governing the kinematical analysis of the augering and concreting stages of the pile construction are introduced. After the description of the test site with the subsoil conditions and the presentation of a typical sets of parameters recorded during pile installation the results of two pile loading tests to failure are reported. A new approach for determining the depth of the soil layers boundaries, based on the statistical analysis of CPT profiles with depth, is proposed and successfully applied confirming the qualitative geological analysis of the site. A further statistical analysis is carried out to find a robust correlation between the qc of the CPT and the torque Mt needed to screw in depth the auger for pile construction. Finally, virtual CPT profiles generated from the torque Mt recorded during the tested piles installation are used for piles bearing capacity calculations which are compared with the results of pile loading tests. The successful comparison reported in the paper is a first step to validate the proposal to use parameters recorded during augering to calculate and/or to confirm design values of the bearing capacity.
{"title":"Drilling parameters as predictors of the measured full scale performance of CFA piles by using statistical analysis of CPT profiles: a case study","authors":"Gianpiero Russo , Ilaria Esposito , Massimo Ramondini , Alessia Vecchietti , Giacomo Russo","doi":"10.1016/j.sandf.2025.101631","DOIUrl":"10.1016/j.sandf.2025.101631","url":null,"abstract":"<div><div>The Continuous Flight Auger (CFA) piles, also known as Auger Cast In Place piles (ACIP), have a widespread use in the world market of replacement concrete piles. The installation of such piles is generally made by equipment which records several significant installation parameters, as the torque M<sub>t</sub> and the axial force N, applied during the auger advancing step. In the auger retrieval stage other parameters that can influence the load-settlement performance of the pile are monitored. The paper presents a case study dealing with the CFA piles adopted as a foundation for a water treatment basin. In the paper first the equations governing the kinematical analysis of the augering and concreting stages of the pile construction are introduced. After the description of the test site with the subsoil conditions and the presentation of a typical sets of parameters recorded during pile installation the results of two pile loading tests to failure are reported. A new approach for determining the depth of the soil layers boundaries, based on the statistical analysis of CPT profiles with depth, is proposed and successfully applied confirming the qualitative geological analysis of the site. A further statistical analysis is carried out to find a robust correlation between the q<sub>c</sub> of the CPT and the torque M<sub>t</sub> needed to screw in depth the auger for pile construction. Finally, virtual CPT profiles generated from the torque M<sub>t</sub> recorded during the tested piles installation are used for piles bearing capacity calculations which are compared with the results of pile loading tests. The successful comparison reported in the paper is a first step to validate the proposal to use parameters recorded during augering to calculate and/or to confirm design values of the bearing capacity.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101631"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170332","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 : 2025-06-01Epub Date: 2025-03-22DOI: 10.1016/j.sandf.2025.101594
Zheng Fan , Yoichi Watabe
Due to economic and demographic growth, there is a rising demand for land reclamation in coastal cities of East and Southeast Asia. Marine clays typically play a critical role in these projects, and the deformation characteristics of marine clays become a crucial problem in terms of the quality of the subsoil conditions. The long-term loading behavior of marine clays has been studied by many researchers. However, relatively few studies have been done on the unloading behavior of these clays after preloading; and thus, the strain rate dependency on the unloading behavior of marine clays remains unclear. The aim of this study was to accumulate experimental data on the unloading behavior of marine clays and to develop a strain rate-based model for improving the accuracy of the predictions of the swelling behavior of marine clays during unloading. The authors conducted a series of constant rate of strain (CRS) consolidation tests from loading to unloading, and long-term unloading oedometer tests on Ariake clay, which is a well-known sensitive marine clay, to observe the swelling behavior during in unloading. The preloading time, corresponding to different strain rates at the end of preloading, was controlled to elucidate the effect of the stress history. Moreover, instead of parameter σ′p (preconsolidation pressure) for the normal consolidation visco-plastic behavior, the authors developed and proposed a new visco-plastic model by introducing the concept of a plastic rebound boundary and a new parameter R for swelling behavior during unloading. Parameter R represents the normalized distance from the current stress state to the plastic rebound boundary in logarithmic effective consolidation stress. Therefore, the visco-plastic model for the behavior in the loading stage was developed into the swelling visco-plastic behavior in the unloading stage for Ariake clay. Comparing the simulation and test results, the simplified visco-plastic swelling model was found to agree well with the test results.
{"title":"Experimental study for modeling the unloading swelling behavior of Ariake clay","authors":"Zheng Fan , Yoichi Watabe","doi":"10.1016/j.sandf.2025.101594","DOIUrl":"10.1016/j.sandf.2025.101594","url":null,"abstract":"<div><div>Due to economic and demographic growth, there is a rising demand for land reclamation in coastal cities of East and Southeast Asia. Marine clays typically play a critical role in these projects, and the deformation characteristics of marine clays become a crucial problem in terms of the quality of the subsoil conditions. The long-term loading behavior of marine clays has been studied by many researchers. However, relatively few studies have been done on the unloading behavior of these clays after preloading; and thus, the strain rate dependency on the unloading behavior of marine clays remains unclear. The aim of this study was to accumulate experimental data on the unloading behavior of marine clays and to develop a strain rate-based model for improving the accuracy of the predictions of the swelling behavior of marine clays during unloading. The authors conducted a series of constant rate of strain (CRS) consolidation tests from loading to unloading, and long-term unloading oedometer tests on Ariake clay, which is a well-known sensitive marine clay, to observe the swelling behavior during in unloading. The preloading time, corresponding to different strain rates at the end of preloading, was controlled to elucidate the effect of the stress history. Moreover, instead of parameter <em>σ′</em><sub>p</sub> (preconsolidation pressure) for the normal consolidation visco-plastic behavior, the authors developed and proposed a new visco-plastic model by introducing the concept of a plastic rebound boundary and a new parameter <em>R</em> for swelling behavior during unloading. Parameter <em>R</em> represents the normalized distance from the current stress state to the plastic rebound boundary in logarithmic effective consolidation stress. Therefore, the visco-plastic model for the behavior in the loading stage was developed into the swelling visco-plastic behavior in the unloading stage for Ariake clay. Comparing the simulation and test results, the simplified visco-plastic swelling model was found to agree well with the test results.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101594"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143686649","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}
Pub Date : 2025-06-01Epub Date: 2025-05-23DOI: 10.1016/j.sandf.2025.101627
Thoi Huu Tra , Thanh T. Nguyen , Thien Q. Huynh , Tatsuya Ishikawa
The load transfer mechanism of pile foundation has received considerable attention over the years, the simultaneous responses that skin friction and base resistances of super-long piles (length L > 60 m) can have in complex soft soil, however, still need greater understanding. This study employs 3D-finite element (FE) analysis incorporating virtual interface elements to simulate the mobilised skin friction and plastic failure (slippage) of pile under ultimate loading. Static pile load tests on 4 different long and large bored piles (1–1.5 m in diameter and 70–80 m in length) embedded in the soft soil region of Mekong Delta are studied in detail through extensive instrumentation along the piles. The results are then used to not only explore load-transfer process, but also validate numerical modelling through a comprehensive process combining multiple-soil layers and −loading stages. The coupled experimental (field) − numerical results reveal the predominant contribution of skin friction exceeding 90 % of the entire bearing capacity before a drop with swift rise in base resistance when reaching a critical condition (displacement sh > 25 mm and load pressure p > 14,000 kPa). The ratio of active skin friction is defined to assess the simultaneous variation of skin friction at different depths, featuring the role of pile length on the mobilisation of skin friction. The study also proposes a novel dynamic method to calculate the strength reduction factor, Ri, based on fundamental soil and load parameters, giving a vital means to advancing the use of interface elements when modelling pile foundation in soft soil.
{"title":"Load transfer behaviour of super long piles in multi-layer soft soil through field testing and numerical 3D FEM modelling","authors":"Thoi Huu Tra , Thanh T. Nguyen , Thien Q. Huynh , Tatsuya Ishikawa","doi":"10.1016/j.sandf.2025.101627","DOIUrl":"10.1016/j.sandf.2025.101627","url":null,"abstract":"<div><div>The load transfer mechanism of pile foundation has received considerable attention over the years, the simultaneous responses that skin friction and base resistances of super-long piles (length <em>L</em> > 60 m) can have in complex soft soil, however, still need greater understanding. This study employs 3D-finite element (FE) analysis incorporating virtual interface elements to simulate the mobilised skin friction and plastic failure (slippage) of pile under ultimate loading. Static pile load tests on 4 different long and large bored piles (1–1.5 m in diameter and 70–80 m in length) embedded in the soft soil region of Mekong Delta are studied in detail through extensive instrumentation along the piles. The results are then used to not only explore load-transfer process, but also validate numerical modelling through a comprehensive process combining multiple-soil layers and −loading stages. The coupled experimental (field) − numerical results reveal the predominant contribution of skin friction exceeding 90 % of the entire bearing capacity before a drop with swift rise in base resistance when reaching a critical condition (displacement <em>s<sub>h</sub></em> > 25 mm and load pressure <em>p</em> > 14,000 kPa). The ratio of active skin friction is defined to assess the simultaneous variation of skin friction at different depths, featuring the role of pile length on the mobilisation of skin friction. The study also proposes a novel dynamic method to calculate the strength reduction factor, <em>R<sub>i</sub></em>, based on fundamental soil and load parameters, giving a vital means to advancing the use of interface elements when modelling pile foundation in soft soil.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101627"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144124583","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 : 2025-06-01Epub Date: 2025-05-21DOI: 10.1016/j.sandf.2025.101601
Kyeongmo Koo, Hyunki Kim
This study proposes an unsupervised Self-Organizing Map (SOM) approach to enhance saturated hydraulic conductivity (ksat) estimation. Using the extensive FLSOIL database of 6,487 soil samples from Florida, the SOM-based ksat estimation model is optimized based on map size and feature selection, then compared with seven empirical equations and three supervised machine learning models. Unlike the other methods, the SOM-based approach provides a probabilistic distribution of ksat, enabling reliability-based design-value determination. Moreover, refining input features particularly by including specific surface area and Kozeny–Carman derived formulas improves accuracy and mitigates bias by the model features, especially in fine-grained soils.
{"title":"Stochastic estimation of soil hydraulic conductivity utilizing self-organizing map method","authors":"Kyeongmo Koo, Hyunki Kim","doi":"10.1016/j.sandf.2025.101601","DOIUrl":"10.1016/j.sandf.2025.101601","url":null,"abstract":"<div><div>This study proposes an unsupervised Self-Organizing Map (SOM) approach to enhance saturated hydraulic conductivity (<em>k<sub>sat</sub></em>) estimation. Using the extensive FLSOIL database of 6,487 soil samples from Florida, the SOM-based <em>k<sub>sat</sub></em> estimation model is optimized based on map size and feature selection, then compared with seven empirical equations and three supervised machine learning models. Unlike the other methods, the SOM-based approach provides a probabilistic distribution of <em>k<sub>sat</sub></em>, enabling reliability-based design-value determination. Moreover, refining input features particularly by including specific surface area and Kozeny–Carman derived formulas improves accuracy and mitigates bias by the model features, especially in fine-grained soils.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101601"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106346","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 : 2025-06-01Epub Date: 2025-05-27DOI: 10.1016/j.sandf.2025.101629
Emma Gardiner, Mark Stringer, Misko Cubrinovski, Sean Rees, Chris McGann
Pumice soil grains are characterized by their vesicular nature, which leads to lightweight, crushable grains with an extremely rough and angular surface texture. These characteristics give pumiceous soils particular engineering properties that are distinct from more commonly encountered hard-grained materials, making them problematic for engineers interested in assessing the risk and potential consequences of liquefaction. Natural pumice-rich soils are found with varying amounts of pumice; however, it remains unclear how the quantity of pumice present in a soil mixture alters the behaviour. This paper investigates the effect of pumice content on cyclic resistance using blends of a hard-grained sand and a pumice sand through a series of triaxial tests. Overall, the cyclic resistance was found to reduce with increasing pumice content. Furthermore, the cyclic resistances appeared to fall into three bands: (a) little apparent reduction in cyclic resistance for pumice contents up to 40%, (b) a reduction in cyclic resistance of approximately 20% at pumice contents of 80% and higher, and (c) a transitional zone. However, despite the lower cyclic resistance, the patterns of pore pressure generation and strain development did not appear to be affected by the amount of pumice in the soil mixture.
{"title":"Effect of pumice content on the undrained cyclic behaviour of pumiceous soil","authors":"Emma Gardiner, Mark Stringer, Misko Cubrinovski, Sean Rees, Chris McGann","doi":"10.1016/j.sandf.2025.101629","DOIUrl":"10.1016/j.sandf.2025.101629","url":null,"abstract":"<div><div>Pumice soil grains are characterized by their vesicular nature, which leads to lightweight, crushable grains with an extremely rough and angular surface texture. These characteristics give pumiceous soils particular engineering properties that are distinct from more commonly encountered hard-grained materials, making them problematic for engineers interested in assessing the risk and potential consequences of liquefaction. Natural pumice-rich soils are found with varying amounts of pumice; however, it remains unclear how the quantity of pumice present in a soil mixture alters the behaviour. This paper investigates the effect of pumice content on cyclic resistance using blends of a hard-grained sand and a pumice sand through a series of triaxial tests. Overall, the cyclic resistance was found to reduce with increasing pumice content. Furthermore, the cyclic resistances appeared to fall into three bands: (a) little apparent reduction in cyclic resistance for pumice contents up to 40%, (b) a reduction in cyclic resistance of approximately 20% at pumice contents of 80% and higher, and (c) a transitional zone. However, despite the lower cyclic resistance, the patterns of pore pressure generation and strain development did not appear to be affected by the amount of pumice in the soil mixture.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101629"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154377","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}
Extensive liquefaction took place in Minami-Kurihashi, Kuki City, Saitama, Japan during the 2011 Off the Pacific Coast of Tohoku Earthquake, which induced damage to houses and infrastructures. Based on the results of a detailed geotechnical investigation, the ground water lowering method has been adopted and executed as a countermeasure against liquefaction. This report summarizes how this countermeasure could be implemented, including the results from field monitoring and relevant analyses of the local ground water level and surface settlement that were conducted during and after the ground water lowering. By newly installing a network of drainage ditches, cut-off sheet pile walls, and operating manhole pumps, it was possible to lower the ground water level in order to prevent/reduce future liquefaction damage. In the non-execution areas outside the cut-off walls, the ground water level was not affected by this operation. As of the end of the monitoring period, the measured maximum settlement and tilting ratio were 36 mm and 1.03/1000, respectively. All the monitoring data satisfied the pre-assigned control limits of 40 mm and 2/1000, respectively. In order to numerically simulate the monitored behavior, modification of the compression index and coefficient of permeability was required. Based on the results of a long-term behavior analysis using the modified parameters, the final settlement and tilting ratio were predicted to be, at maximum, 54 mm and 1.50/1000, respectively. The latter value satisfied the pre-assigned threshold limit of 3/1000.
{"title":"Ground water lowering at Minami-Kurihashi in Kuki City, Japan as countermeasure against liquefaction","authors":"Junichi Koseki , Kazue Wakamatsu , Katsuya Matsushita , Tomoaki Yahaba","doi":"10.1016/j.sandf.2025.101597","DOIUrl":"10.1016/j.sandf.2025.101597","url":null,"abstract":"<div><div>Extensive liquefaction took place in Minami-Kurihashi, Kuki City, Saitama, Japan during the 2011 Off the Pacific Coast of Tohoku Earthquake, which induced damage to houses and infrastructures. Based on the results of a detailed geotechnical investigation, the ground water lowering method has been adopted and executed as a countermeasure against liquefaction. This report summarizes how this countermeasure could be implemented, including the results from field monitoring and relevant analyses of the local ground water level and surface settlement that were conducted during and after the ground water lowering. By newly installing a network of drainage ditches, cut-off sheet pile walls, and operating manhole pumps, it was possible to lower the ground water level in order to prevent/reduce future liquefaction damage. In the non-execution areas outside the cut-off walls, the ground water level was not affected by this operation. As of the end of the monitoring period, the measured maximum settlement and tilting ratio were 36 mm and 1.03/1000, respectively. All the monitoring data satisfied the pre-assigned control limits of 40 mm and 2/1000, respectively. In order to numerically simulate the monitored behavior, modification of the compression index and coefficient of permeability was required. Based on the results of a long-term behavior analysis using the modified parameters, the final settlement and tilting ratio were predicted to be, at maximum, 54 mm and 1.50/1000, respectively. The latter value satisfied the pre-assigned threshold limit of 3/1000.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101597"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644395","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}
Pub Date : 2025-06-01Epub Date: 2025-04-15DOI: 10.1016/j.sandf.2025.101618
Bo Huang, Lin-Feng Cao, Yu-Chao Li
The composite geomembrane-soil-bentonite (CGSB) cutoff wall is one of the most effective barriers to prevent pollutant transport in groundwater. However, geomembranes may have defects during construction, significantly increasing the risk of pollutant leakage. Currently, little is known about pollutant transport at the interface between defective geomembranes and soil-bentonite (SB) cutoff walls. This paper presents the results from centrifuge experiments modelling pollutants transport within a defective CGSB wall to investigate interface transport behavior and its performance. Additionally, a parallel test on the SB wall is performed simultaneously to evaluate the enhancement effect of a defective geomembrane on the performance of SB walls. The results show that although the proportion of defect areas on the geomembrane is minimal, the lateral fluid flow at the interface significantly increases both the leakage and pollution area of the CGSB wall. The breakthrough points of pollutants in the SB and CGSB walls differ, with one occurring in the shallow part of the wall and the other at the center of the geomembrane defect. Numerical simulations are conducted at the centrifuge model scale, and the calculated results are consistent with the experiments. Simulation results suggest that although the CGSB wall with geomembrane defects does not significantly prolong breakthrough time compared to the SB wall, it markedly reduces pollutant flux.
{"title":"Pollutant transport and performance evaluation in defective composite cutoff walls: centrifuge test and numerical simulation","authors":"Bo Huang, Lin-Feng Cao, Yu-Chao Li","doi":"10.1016/j.sandf.2025.101618","DOIUrl":"10.1016/j.sandf.2025.101618","url":null,"abstract":"<div><div>The composite geomembrane-soil-bentonite (CGSB) cutoff wall is one of the most effective barriers to prevent pollutant transport in groundwater. However, geomembranes may have defects during construction, significantly increasing the risk of pollutant leakage. Currently, little is known about pollutant transport at the interface between defective geomembranes and soil-bentonite (SB) cutoff walls. This paper presents the results from centrifuge experiments modelling pollutants transport within a defective CGSB wall to investigate interface transport behavior and its performance. Additionally, a parallel test on the SB wall is performed simultaneously to evaluate the enhancement effect of a defective geomembrane on the performance of SB walls. The results show that although the proportion of defect areas on the geomembrane is minimal, the lateral fluid flow at the interface significantly increases both the leakage and pollution area of the CGSB wall. The breakthrough points of pollutants in the SB and CGSB walls differ, with one occurring in the shallow part of the wall and the other at the center of the geomembrane defect. Numerical simulations are conducted at the centrifuge model scale, and the calculated results are consistent with the experiments. Simulation results suggest that although the CGSB wall with geomembrane defects does not significantly prolong breakthrough time compared to the SB wall, it markedly reduces pollutant flux.</div></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"65 3","pages":"Article 101618"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143829064","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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