Soils and Foundations最新文献

{"title":"Electroosmotic reinforcement mechanism and laboratory tests of pulsating direct current with a high energy efficiency ratio","authors":"Xunli Zhang ,&nbsp;Lingwei Zheng ,&nbsp;Shangqi Ge ,&nbsp;Xudong Zheng ,&nbsp;Xinyu Xie","doi":"10.1016/j.sandf.2024.101423","DOIUrl":"https://doi.org/10.1016/j.sandf.2024.101423","url":null,"abstract":"<div><p>Based on the electroosmotic reinforcement mechanism of pulsating direct current (PDC) with a high energy efficiency ratio, the calculation method of PDC electroosmosis drainage rate was verified under different potential gradients using two forms of voltage loading, i.e., constant direct current (CDC) and PDC. The drainage weight and electric current were achieved by laboratory tests, and then the energy efficiency ratio, soil resistivity and contact resistance was calculated. The energy consumption of each test group was analyzed by considering the initial potential gradient. The obtained results show that under the same potential gradient, the difference in soil resistivity and electroosmotic drainage between PDC and CDC is not significant, but there is a significant difference in contact resistance, which leads to low current intensity and high energy efficiency ratio in the PDC test group. The expression of the electroosmotic drainage rate of the PDC is described with the coefficient μ, and then the energy efficiency ratio versus potential gradient curve is calculated, which is in good agreement with the experimental results. The reason for the lower energy consumption of PDC electroosmosis compared to CDC is described in terms of the drainage mechanism of electroosmosis.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101423"},"PeriodicalIF":3.7,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080624000015/pdfft?md5=d29542071600ab5d505c84df053ff0a6&pid=1-s2.0-S0038080624000015-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139549349","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":"Centrifuge modeling of pile-supported embankment on soft soil base for highway widening","authors":"Tianyi Chen,&nbsp;Ga Zhang","doi":"10.1016/j.sandf.2023.101422","DOIUrl":"10.1016/j.sandf.2023.101422","url":null,"abstract":"<div><p>The pile-supported embankment has been widely adopted in highway widening projects. There is often significant differential settlement between the new and old embankments. Previous studies have not clarified the interaction mechanisms between different parts of the widening subgrade. In this research, a series of centrifuge model tests were carried out on the subgrades widened by pile-supported embankment on the soft soil base. The effect of the old embankment and piles on the subgrade deformation subject to new embankment is analyzed based on the full-field measurement results of displacement. The embankment displacement is mainly vertically downward and basically caused by the deformation of the soft soil base. The old embankment redistributes the vertical deformation of soft soil base by increasing and decreasing the vertical displacement in turn along the direction towards the slope surface. The piles exhibit supporting effect on the embankment above and restrict the vertical movement of the soil base. The piles influence the deformation of soft soil base within a certain area which expands with the increasing number of piles. The boundary of the pile influential area moves towards the subgrade axis with increasing depth. The vertical deformation of soft soil base shows peaks that are nearly linearly distributed along depth in the pile influential area. As the number of piles increases, the verticality degree of such linear distribution changes from the vertical to the slope firstly and then reverts to the vertical.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101422"},"PeriodicalIF":3.7,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001518/pdfft?md5=f7606a3f3276cf876e06d784f4007517&pid=1-s2.0-S0038080623001518-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139103060","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":"Settlement prediction of shallow foundations for quality controls of sandy hydraulic fills","authors":"V. Fioravante ,&nbsp;D. Giretti ,&nbsp;A. Masella ,&nbsp;G. Vaciago","doi":"10.1016/j.sandf.2023.101408","DOIUrl":"10.1016/j.sandf.2023.101408","url":null,"abstract":"<div><p>This paper describes a procedure for settlement prediction of shallow foundations on carbonate sands, but it is fully applicable and valid for siliceous sands. For practical purposes, the design of shallow foundations resting on medium dense and dense granular soils is typically governed by limiting settlement to tolerable values. Predicting foundation settlement is therefore important, but in standard practice it is necessarily based on indirect (and therefore often conservative) determinations of soil compressibility (or modulus), due to the intrinsic difficulties in obtaining direct measurements.</p><p>While numerical analyses incorporating non-linear soil behaviour may be a preferred method for computing expected total and differential settlement of shallow foundations of given geometry and stiffness on sand under static loading, the method described in this paper consists of a simplified and expeditious method based on equivalent linear elasticity. The method uses: i) the elastic soil stiffness profile at small strain, E₀(z) obtained from the shear wave velocity as the primary measurement of deformability and ii) the reduction in modulus as a function of strain magnitude, E(ε) to account for stiffness non-linearity. The beneficial effect on the soil initial stiffness of the applied footing load is also considered. The method was developed as an on-site tool for checking the compaction of hydraulic fills made of carbonate sand to form artificial islands, but its application can be extended to other natural and anthropogenic coarse-grained materials.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101408"},"PeriodicalIF":3.7,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001373/pdfft?md5=9768d5997b0ab176fc1698b88ca34c74&pid=1-s2.0-S0038080623001373-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139064261","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":"Numerical investigation of the installation process and bearing capacity of circular helicoid piles in undrained clay","authors":"Kunpeng Wang ,&nbsp;Chunyi Cui ,&nbsp;Peng Zhang ,&nbsp;Noriyuki Yasufuku ,&nbsp;Guangli Xu ,&nbsp;Meng Wang","doi":"10.1016/j.sandf.2023.101411","DOIUrl":"10.1016/j.sandf.2023.101411","url":null,"abstract":"<div><p>The circular helicoid pile (CH pile) is a special-shaped pile with outstanding axial bearing properties developed in the last ten years, its pile-soil interaction problem has nonplanar strain and is non-axisymmetric. The coupled Eulerian-Lagrangian (CEL) method was applied to simulate the entire process of installation, axial compression and pullout loading of the CH pile in undrained clay to assess the interaction between the pile and soil, and the accuracy of the CEL model was verified by in-situ test results. The surfaces of the CH pile were divided into the bottom surface, outer and inner surfaces, with the inner surfaces including compressive and pullout surfaces. The variation in axial forces and moments on the CH pile and its various types of surfaces in the whole process of installation and bearing was clarified and the relative contribution of reacting forces and moments on various surfaces to the total resistance of the pile was evaluated. The stress distribution characteristics of the soil around the pile and the pile-soil interfaces after the installation of the CH pile and under the ultimate limit state were obtained, and then the force states of inner surfaces in the whole process of installation and bearing were analysed.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101411"},"PeriodicalIF":3.7,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001403/pdfft?md5=011016959006e03ce8e606fa906ae2bf&pid=1-s2.0-S0038080623001403-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139064268","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":"Mixture design for eco-friendly hybrid clay treated with two stabilizers based on water absorption and retention of stabilizers","authors":"Shafique Raihan Shovon ,&nbsp;Alula Kassa ,&nbsp;Ryo Sekine ,&nbsp;Kimitoshi Hayano ,&nbsp;Yoshitoshi Mochizuki","doi":"10.1016/j.sandf.2023.101403","DOIUrl":"10.1016/j.sandf.2023.101403","url":null,"abstract":"<div><p>Major challenges are encountered when using high-water-content clays as construction materials owing to their low shear strength and high compressibility. Processes, such as sun drying and stabilization using chemical agents, can address the problems met with these clays during their conveyance and reuse. However, natural dehydration is a time-consuming process, and chemical stabilization can lead to an increase in the hydrogen ion index (pH) of the surrounding environment. Thus, the aim of this study is to improve the performance of high-water-content clay using a combination of green and byproduct materials, specifically bamboo chips and fly ash, which are cost-effective and eco-friendly. No previous study has attempted to design a mixture for the purpose of improving the performance of clay based on the water absorption and retention performance of stabilizers. In this study, the water absorption and retention rate (<em>W</em>_ab), which is the mass of the water absorbed and retained by 1 g of each stabilizer, was measured by removing the unabsorbed and unretained water through filtration under vacuum suction. A series of Cone Index tests were conducted on clay, separately treated with bamboo chips and fly ash, and the tests demonstrated a correlation among the Cone Index (<em>q</em>_c), <em>W</em>_ab, and amount of stabilizer added (<em>A</em>_st). A novel mixture design was proposed for hybrid-treated clay, using the two types of stabilizers in the composite, based on parameter <em>β</em>, which is defined as the sum of the product (<em>W</em>_ab/100)×(<em>A</em>_st/100) of each stabilizer used in the hybrid-treated clay. The results of the Cone Index tests performed on the hybrid-treated clay showed that the proposed mixture design can predict the combinations of certain amounts of each stabilizer needed to attain the target <em>q</em>_c with minimal errors. The results of pH measurement tests indicated that the hybrid-treated clays produced by the proposed mixture design were more eco-friendly than fly ash-treated clays. Furthermore, the theoretical maximum CO₂ fixation capacities of the hybrid-treated clays were evaluated to assess their feasibility as CO₂-fixing materials.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101403"},"PeriodicalIF":3.7,"publicationDate":"2023-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001324/pdfft?md5=83a5141bb9096c8c45d4927c40aa9e7a&pid=1-s2.0-S0038080623001324-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139056926","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":"Prediction of ground vibration under combined seismic and high-speed train loads considering earthquake intensity and site category","authors":"Wei Xie ,&nbsp;Guangyun Gao ,&nbsp;Jian Song ,&nbsp;Yonggang Jia","doi":"10.1016/j.sandf.2023.101412","DOIUrl":"10.1016/j.sandf.2023.101412","url":null,"abstract":"<div><p>Based on a two-and-half-dimensional finite element model (2.5D FEM), the layered ground vibration under combined seismic and high-speed train loads was investigated. On this basis, the effect of site category and earthquake intensity on ground vibration under the combined action of two dynamic loads was analyzed. Numerical examples indicated that ground vibration displacement due to combined loads decreases with the increase of soil stiffness, while the influence of soil stiffness on the ground vibration is small when the hardness of the subsoil is large. The peak ground displacement (PGD) is a reasonable seismic intensity index for predicting the ground vibration displacement at the track center under the combined loads, which has a higher accuracy for hard ground. In view of this, an equivalent shear wave velocity and PGD-based prediction formula was proposed to estimate the ground vibration under combined seismic and high-speed train loads. Reliability of the prediction formula was verified through comparison with results of numerical tests, indicating that the prediction formula has good applicability to different site conditions and seismic events. Compared with the previous study, it demonstrated that the prediction method provided an effective means for estimating ground vibration caused by a high-speed train load during earthquakes.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101412"},"PeriodicalIF":3.7,"publicationDate":"2023-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001415/pdfft?md5=3d0c90c8f6265f0e80189083e1c2a0aa&pid=1-s2.0-S0038080623001415-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139028707","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":"Vacuum consolidation effect on the hydromechanical properties of the unusual soft clays of the former Texcoco Lake","authors":"Norma Patricia López-Acosta,&nbsp;Alejandra Liliana Espinosa-Santiago","doi":"10.1016/j.sandf.2023.101410","DOIUrl":"https://doi.org/10.1016/j.sandf.2023.101410","url":null,"abstract":"<div><p>The area of the former Texcoco Lake in Mexico is characterized by soft lacustrine clay strata with high water content and high compressibility. The construction of a new airport was planned in this area, which requires soil stabilization. One soil improvement option is the use of vacuum preloading systems that apply a vacuum to the soil through vertical drains. This study evaluates the improvement on hydromechanical properties resulting from the implementation of two vacuum techniques. In 2016, two test embankments with surcharge preloading and vertical drains were constructed to apply a vacuum using the drain-to-drain technique in one embankment and the airtight membrane technique in the other. The average vacuum pressures applied for six months in the test embankments were −58 kPa and −63 kPa with the drain-to-drain and airtight membrane techniques, respectively. The improvement on the properties varied between the two techniques. The airtight membrane technique reduced the water content and the void ratio up to 50 % and 46 %, respectively. While the drain-to-drain technique reduced the water content and the void ratio up to 15 % and 13 %, respectively. The degree of consolidation estimated using different observational methods at the center of both test embankments ranged from 86 % to 88 %.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101410"},"PeriodicalIF":3.7,"publicationDate":"2023-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001397/pdfft?md5=f250f2ba9fc69b87db97abfad124321c&pid=1-s2.0-S0038080623001397-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139033802","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":"Evaluation of the effect of constant and non-constant Poisson’s ratio on reinforcement load of reinforced soil walls","authors":"Mauricio Ehrlich ,&nbsp;Seyed Hamed Mirmoradi ,&nbsp;Gustavo Fonseca Silva ,&nbsp;Gabriel Nascimento","doi":"10.1016/j.sandf.2023.101409","DOIUrl":"https://doi.org/10.1016/j.sandf.2023.101409","url":null,"abstract":"<div><p>This study analytically and numerically investigates the impact of constant and non-constant Poisson’s ratio on the mobilized maximum load in the reinforcements, T_max, of reinforced soil walls with vertical facing under working stress conditions. This assessment is carried out considering different controlling factors including reinforcement stiffness, wall height, backfill friction angle, and compaction-induced stress. The analytical procedure and the numerical model are validated against data from an instrumented, large-scale, geosynthetic-reinforced soil wall under working stress conditions. Considering the key factors evaluated in the current study, the results show that the impact of the reinforcement stiffness is dominant over the approach used to consider Poisson’s ratio. A maximum difference of about 20% was obtained between the values of T_max calculated using constant and variable Poisson’s ratios. This implies that, from a practical standpoint, it may be appropriate to adopt a simpler approach that utilizes a constant Poisson's ratio for the determination of T_max under operational conditions.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101409"},"PeriodicalIF":3.7,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001385/pdfft?md5=2d83a54ec5823360d4ca31671a663e95&pid=1-s2.0-S0038080623001385-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138839615","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":"Test conditions influence on thermal conductivity and contact conductance of sand at transient state","authors":"Kamar Aljundi ,&nbsp;Carlos Pereira ,&nbsp;Ana Vieira ,&nbsp;João R. Maranha ,&nbsp;José Lapa ,&nbsp;Rafaela Cardoso","doi":"10.1016/j.sandf.2023.101405","DOIUrl":"10.1016/j.sandf.2023.101405","url":null,"abstract":"<div><p>The proper assessment of soil thermal properties, such as thermal conductivity, assumes a particular relevance for the design of Ground Source Heat Pump systems, as it determines the heat transfer and the energy efficiency design. Multiple methods can be used for thermal conductivity estimation, however significant scatters in measurements are often reported when using different (or even the same) methods. This work presents a detailed study of the thermal conductivity and the thermal contact conductance of a reference sand tested in transient conditions, analyzing the effect of several factors, such as the heating time, degree of saturation, soil density, temperature and heat flux intensity, on thermal conductivity measurements for dry state or fully saturated conditions. To avoid measurement errors and heterogeneity effects, only three samples were prepared with different compaction ratios, and systematically tested in dry and fully saturated conditions, under different control variables (temperature, testing time, and injected heat flux). Two analytical methods based on the line source solution were used to estimate soil thermal conductivity and to assess the probe-to-soil thermal contact conductance. Significant relationships were obtained between thermal conductivity and soil state conditions and testing variables, highlighting that a heating time longer than the one usually recommended in the standards is clearly needed. Finally, this study uses measured temperature values to determine the probe-to-soil thermal contact conductance, indicating its relevance in soil thermal conductivity estimation.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101405"},"PeriodicalIF":3.7,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001348/pdfft?md5=76ed99b5d4c0553b7c367a2576a73bc0&pid=1-s2.0-S0038080623001348-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138817969","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":"Critical application zone of the jet grouting piles in the vicinity of existing high-speed railway bridge in deep soft soils with medium sensibility","authors":"Yao Shan ,&nbsp;Jun Luo ,&nbsp;Binglong Wang ,&nbsp;Shunhua Zhou ,&nbsp;Bo Zhang","doi":"10.1016/j.sandf.2023.101407","DOIUrl":"https://doi.org/10.1016/j.sandf.2023.101407","url":null,"abstract":"<div><p>Jet grouting piles were widely employed for ground reinforcement in building and infrastructure engineering due to the low cost and construction convenience. However, this foundation treatment method is not allowed to be used in high-speed railway involved constructions in China because of the concerning of the negative effect on the lateral displacement of the existing high-speed railway. To find a reasonable application distance of jet grouting piles away from existing high-speed railway bridge in deep soft soils with medium sensibility, a series of laboratory and in-situ tests on the influence of the jet grouting piling on the deformation of surrounding soils and adjacent high-speed railway bridge are carried out. The geological characteristics of the construction site and the mechanical properties of the soft soil are deeply investigated by utilizing field and laboratory tests. The piling induced lateral displacement of the surrounding soils is monitored as well as the displacement of an adjacent high-speed railway bridge. The monitoring data reveal that the influence area of the jet grouting piling is approximately 1.75 ∼ 1.85 times of the pile length in deep soft soils. The critical distance of the jet grouting piles from the existing high-speed bridge should be larger than 2 times of the pile length.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 1","pages":"Article 101407"},"PeriodicalIF":3.7,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080623001361/pdfft?md5=096ce22104770a87a47400f52e0cbe40&pid=1-s2.0-S0038080623001361-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138713449","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}