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Urban Freight Consolidation Model for Post-Hauler Planning
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作者 Mohammad Anwar Rahman 《Journal of Transportation Technologies》 2024年第2期255-272,共18页
Freight transportation in urban areas has increased significantly in a shorter period due to the widespread use of e-commerce, fast delivery, and population growth. Recently, a noticeable government initiative aimed a... Freight transportation in urban areas has increased significantly in a shorter period due to the widespread use of e-commerce, fast delivery, and population growth. Recently, a noticeable government initiative aimed at creating an effective, acceptable, and sustainable city logistics policy. This paper examines freight consolidation as a transportation strategy for optimizing last-mile delivery costs. Freight consolidation involves combining smaller shipments from various origins into a single, larger shipment for more efficient transportation to a common destination. This approach is particularly beneficial for last-mile delivery, where frequent deliveries of smaller quantities are frequently visible. Finally, we provide an illustrative example targeting urban freight stakeholders for practicing possible consolidation methodology. The result in the illustrative example shows that freight with 3-day consolidation, despite the delay penalty, is cheaper than daily shipping, and both are cheaper than 2-day consolidated shipping. The study will benefit urban businesses and freight services. 展开更多
关键词 Freight consolidation Urban Transport Intermodal Last-Mile Delivery
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Effect of particle composition and consolidation degree on the wave-induced liquefaction of soil beds
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作者 Zhiyuan Chen Yupeng Ren +1 位作者 Guohui Xu Meng Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期11-22,共12页
The wave-induced liquefaction of seabed is responsible for causing damage to marine structures.Particle composition and consolidation degree are the key factors affecting the pore water pressure response and liquefact... The wave-induced liquefaction of seabed is responsible for causing damage to marine structures.Particle composition and consolidation degree are the key factors affecting the pore water pressure response and liquefaction behavior of the seabed under wave action.The present study conducted wave flume experiments on silt and silty fine sand beds with varying particle compositions.Furthermore,a comprehensive analysis of the differences and underlying reasons for liquefaction behavior in two different types of soil was conducted from both macroscopic and microscopic perspectives.The experimental results indicate that the silt bed necessitates a lower wave load intensity to attain the liquefaction state in comparison to the silty fine sand bed.Additionally,the duration and development depth of liquefaction are greater in the silt bed.The dissimilarity in liquefaction behavior between the two types of soil can be attributed to the variation in their permeability and plastic deformation capacity.The permeability coefficient and compression modulus of silt are lower than those of silty fine sand.Consequently,silt is more prone to the accumulation of pore pressure and subsequent liquefaction under external loading.Prior research has demonstrated that silt beds with varying consolidation degrees exhibit distinct initial failure modes.Specifically,a dense bed undergoes shear failure,whereas a loose bed experiences initial liquefaction failure.This study utilized discrete element simulation to examine the microscopic mechanisms that underlie this phenomenon. 展开更多
关键词 wave flume LIQUEFACTION pore water pressure consolidation permeability experiment discrete element simulation
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Shape Analysis of Agricultural Parcels for Land Consolidation Priorities in Tekirdag Province,Turkey
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作者 Bahadir ALTURK 《Chinese Geographical Science》 SCIE CSCD 2024年第1期93-105,共13页
Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significan... Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significantly to spatial prioritization where there is also a high probability of achieving positive effects of consolidation projects.This study aims to determine the shape degree of the agricultural parcels both at singular and rural county scales in Tekirdag Province,Turkey in 2020 by combining the parcel shape index(PSI) with the minimum bounding geometry index(MBG) to improve parcel scores.Hot-spot zones of the highly irregular and near optimum parcels were also determined using Getis-Ord G_(i)^(*) statistic.The parcel degrees were classified into four categories,namely highly irregular,irregular,regular and near optimum.The obtained unweighted scores of the parameters exhibit deviations from the expected values.After weighting by pairwise comparison,the values approached ideal scores.Among 346 740 parcels,53% were highly irregular and irregular and 47% were regular and near optimum shapes after weighting whereas these were 70% and 30%,respectively before weighting.The average parcel degree of 63 rural counties was regular while the average parcel degree of the remaining 264 rural counties was irregular.The combined use of PSI and MBG index improved the correctness of the parcel shape score.It could be suggested to use as a tool in land consolidation prioritization. 展开更多
关键词 land consolidation priority parcel shape index(PSI) minimum bounding geometry(MBG) sustainable rural development hot-spot analysis Tekirdag Province TURKEY
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Spatiotemporal variations in ecosystem services and their trade-offs and synergies against the background of the gully control and land consolidation project on the Loess Plateau,China
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作者 WANG Jing WEI Yulu +2 位作者 PENG Biao LIU Siqi LI Jianfeng 《Journal of Arid Land》 SCIE CSCD 2024年第1期131-145,共15页
Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implicatio... Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River Basin.Therefore,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.We also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological environment.The results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,respectively.The ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were significant.The GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more significant.This study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and ecological security. 展开更多
关键词 ecosystem services trade-offs and synergies gully control and land consolidation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model Loess Plateau
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Meningeal T-cells in the cross-talk between memory consolidation and sleep
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作者 Rodrigo Pacheco Valentina Ugalde 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2687-2688,共2页
Some years ago,the infiltration of T-cells into the central nervous system(CNS) was considered a pathological condition exclusively.However,during the last two decades,a growing body of studies has shown that T-cells ... Some years ago,the infiltration of T-cells into the central nervous system(CNS) was considered a pathological condition exclusively.However,during the last two decades,a growing body of studies has shown that T-cells are essential players regulating several physiological processes exerted by the CNS,including stress resilience,social behavior. 展开更多
关键词 behavior. SLEEP consolidation
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Physical model investigation on effects of drainage condition and cement addition on consolidation behavior of tailings slurry within backfilled stopes
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作者 Qinghai Ma Guangsheng Liu +1 位作者 Xiaocong Yang Lijie Guo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第8期1490-1501,共12页
Estimation of stressses within the tailings slurry during self-weight consolidation is a critical issue for cost-effective barricade design and efficient backfill planning in underground mine stopes.This process requi... Estimation of stressses within the tailings slurry during self-weight consolidation is a critical issue for cost-effective barricade design and efficient backfill planning in underground mine stopes.This process requires a good understanding of self-weight consolidation behaviors of the tailings slurry within practical stopes,where many factors can have significant effects on the consolidation,including drainage condition and cement addition.In this paper,the prepared tailings slurry with different cement contents(0,4.76wt%,and 6.25wt%)was poured into1.2 m-high columns,which allowed three drainage scenarios(undrained,partial lateral drainage near the bottom part,and full lateral drainage boundaries)to investigate the effects of drainage condition and cement addition on the consolidation behavior of the tailings slurry.The consolidation behavior was analyzed in terms of pore water pressure(PWP),settlement,volume of drainage water,and residual water content.The results indicate that increasing the length of the drainage boundary or cement content aids in PWP dissipation.In addition,constructing an efficient drainage boundary was more favorable to PWP dissipation than increasing cement addition.The final stable PWP on the column floor was not sensitive to cement addition.The final settlement of uncemented tailings slurry was independent of drainage conditions,and that of cemented tailings slurry decreased with the increase in cement addition.Notably,more pore water can drain out from the cemented tailings slurry than the uncemented tailings slurry during consolidation. 展开更多
关键词 tailings backfill consolidation slurry drainage cement content physical model test
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Virtual Machine Consolidation with Multi-Step Prediction and Affinity-Aware Technique for Energy-Efficient Cloud Data Centers
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作者 Pingping Li Jiuxin Cao 《Computers, Materials & Continua》 SCIE EI 2023年第7期81-105,共25页
Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,... Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,but the current schemes commonly ignore the long-term relationship between VMs and hosts.In addition,there is a lack of long-term consideration for resource optimization in the VM consolidation,which results in unnecessary VM migration and increased energy consumption.To address these limitations,a VM consolidation method based on multi-step prediction and affinity-aware technique for energy-efficient cloud data centers(MPaAF-VMC)is proposed.The proposed method uses an improved linear regression prediction algorithm to predict the next-moment resource utilization of hosts and VMs,and obtains the stage demand of resources in the future period through multi-step prediction,which is realized by iterative prediction.Then,based on the multi-step prediction,an affinity model between the VM and host is designed using the first-order correlation coefficient and Euclidean distance.During the VM consolidation,the affinity value is used to select the migration VM and placement host.The proposed method is compared with the existing consolidation algorithms on the PlanetLab and Google cluster real workload data using the CloudSim simulation platform.Experimental results show that the proposed method can achieve significant improvement in reducing energy consumption,VM migration costs,and service level agreement(SLA)violations. 展开更多
关键词 Cloud computing VM consolidation multi-step prediction affinity relationship energy efficiency
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Strength Model of Soda Residue Soil Considering Consolidation Stress and Structural Influence
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作者 GONG Xiaolong WANG Yuanzhan CHEN Tong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1216-1226,共11页
Soda residue(SR)is a type of industrial waste produced in the soda process with the ammonia-soda method.Applying SR to backfilling solves the land occupation and environmental pollution problems in coastal areas and s... Soda residue(SR)is a type of industrial waste produced in the soda process with the ammonia-soda method.Applying SR to backfilling solves the land occupation and environmental pollution problems in coastal areas and saves material costs for foundation engineering.The strength characteristics of soda residue soil(SRS)under different consolidation conditions are the key points to be solved in the engineering application of SRS.Triaxial compression tests were performed on the undisturbed SRS of Tianjin Port.The shear properties of SRS under different consolidation conditions were then discussed.Meanwhile,a structural strength model(SSM)based on Mohr-Coulomb theory was proposed.SSM reflects the influence of soil structure on undrained strength(Cu)and divides the Cu into the following two parts:friction strength(C_(uf))and original structural strength(C_(u0)).C_(uf)characterizes the magnitude of friction between soil particles,which is related to the consolidation stress.Meanwhile,C_(u0)represents the structural effect on soil strength,which is related to the soil deposition and consolidation processes.SSM was validated by the test data of undisturbed soils.Results reveal that the undisturbed soil generally had a certain C_(u0).Therefore,the SRS strength model was established by combining the experimental law of SRS with SSM.Error analysis shows that the SRS strength model can effectively predict the Cu of undisturbed SRS in Tianjin Port under different consolidation conditions. 展开更多
关键词 soda residue soil triaxial test strength model soil structure consolidation stress
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Exploration on the Path of Whole-region Comprehensive Land Consolidation under the Background of Rural Revitalization
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作者 Xueli CAI Shiqin YANG 《Asian Agricultural Research》 2023年第6期1-6,共6页
Based on the specific concept of whole-region comprehensive land consolidation and the development history of land consolidation in China,the internal relationship between rural revitalization strategy and whole-regio... Based on the specific concept of whole-region comprehensive land consolidation and the development history of land consolidation in China,the internal relationship between rural revitalization strategy and whole-region comprehensive land consolidation is clarified from the perspective of historical development,and the problems faced by whole-region comprehensive land consolidation,such as rural"hollowing out",weak linkage between execution departments and neglect of ecological restoration,are deeply analyzed.Furthermore,some new paths for whole-region land consolidation are put forward,such as strengthening the top-level system design,handling the relationship between stock and increment,evaluating the potential of rural land consolidation,coordinating the win-win cooperation between middle-level executive departments,encouraging the innovation at the bottom and enhancing the comprehensive management of ecological environment. 展开更多
关键词 Rural revitalization Whole-region comprehensive land consolidation Path EXPLORATION
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Two-dimensional plane strain consolidation of unsaturated soils considering the depth-dependent stress
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作者 Lei Wang Sidong Shen +2 位作者 Tianyi Li Minjie Wen Annan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1603-1614,共12页
In practical engineering,the total vertical stress in the soil layer is not constant due to stress diffusion,and varies with time and depth.Therefore,the purpose of this paper is to investigate the effect of stress di... In practical engineering,the total vertical stress in the soil layer is not constant due to stress diffusion,and varies with time and depth.Therefore,the purpose of this paper is to investigate the effect of stress diffusion on the two-dimensional(2D)plane strain consolidation properties of unsaturated soils when the stress varies with time and depth.A series of semi-analytical solutions in terms of excess pore air and water pressures and settlement for 2D plane strain consolidation of unsaturated soils can be derived with the joint use of Laplace transform and Fourier sine series expansion.Then,the inverse Laplace transform of the semi-analytical solution is given in the time domain using a self-programmed code based on Crump’s method.The reliability of the obtained solutions is proved by the degeneration.Finally,the 2D plots of excess pore pressures and the curves of settlement varying with time,considering different physical parameters of unsaturated soil stratum and depth-dependent stress,are depicted and analyzed to study the 2D plane strain consolidation properties of unsaturated soils subjected to the depthdependent stress. 展开更多
关键词 Semi-analytical solutions Two-dimensional(2D)plane strain consolidation Unsaturated soils Depth-dependent stress Laplace transform
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Pulmonary reversed halo cycles and consolidations after immunotherapy:A case report
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作者 Hong Suo Yu-Jie Shi +2 位作者 Zhao-Di Huang Kai Xu Hui Huang 《World Journal of Clinical Cases》 SCIE 2023年第28期6938-6942,共5页
BACKGROUND Immune checkpoint inhibitor-associated interstitial lung disease(ICI-ILD)and opportunistic pneumonias are the main pulmonary complications during immunotherapy for malignancies.The organizing pneumonia(OP)p... BACKGROUND Immune checkpoint inhibitor-associated interstitial lung disease(ICI-ILD)and opportunistic pneumonias are the main pulmonary complications during immunotherapy for malignancies.The organizing pneumonia(OP)pattern is one of the common radiological manifestations of ICI-ILD,and OP is the most common cause of reversed halo cycles and consolidations.However,opportunistic pneumonias should be excluded.CASE SUMMARY In this report,we described a case of a 44-year-old man with esophageal cancer who showed multiple reversed-halo cycles and consolidations on chest computed tomography(CT)after he had a cold during immunotherapy.He was diagnosed with esophageal squamous-cell cancer(T2NIM0)after surgery.Then,he was successfully treated with 6 cycles of chemotherapy plus tislelizumab,one cycle of radiotherapy and 9 cycles of tislelizumab.Two months later,he complained of low-grade fever and cough with nonpurulent sputum after he had a cold.Community-acquired pneumonia was considered,but moxifloxacin was ineffective.Chest CT showed multiple reversed-halo cycles and consolidations.Mycobacterium tuberculosis was identified with next-generation sequence analysis of bronchoalveolar lavage fluid(BALF).Two months later,he improved with standard anti-tuberculosis medications.Both the cycles and consolidations disappeared in the repeat CT after 6 mo of medications.CONCLUSION When chest CT shows reversed-halo cycles and consolidations in patients during anticancer immunotherapy,both ICI-ILD and infectious pneumonia should be considered.BALF microbiological analysis was helpful to differentiate them. 展开更多
关键词 Reversed halo cycles consolidations IMMUNOTHERAPY TUBERCULOSIS Checkpoint inhibitor associated interstitial lung disease Case report
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One-dimensional large-strain consolidation of soft clay with non-Darcian flow and nonlinear compression and permeability of soil 被引量:11
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作者 李传勋 王昌建 +2 位作者 卢萌盟 陆建飞 谢康和 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期967-976,共10页
Geometrical nonlinearity of the soft soil and the deviation of water flow in the soft clay from Darcy's law have been well recognized in practice. However, the theory of consolidation, which can account for both t... Geometrical nonlinearity of the soft soil and the deviation of water flow in the soft clay from Darcy's law have been well recognized in practice. However, the theory of consolidation, which can account for both the geometrical nonlinearity and the non-Darcian flow, has not been reported so far. In this contribution, a model for the consolidation of soft clay which can allow for these two factors simultaneously is proposed. Utilizing the finite difference method, the numerical model for this problem is developed. With the numerical model, the effects of the geometrical nonlinearity and the non-Darcian flow on the consolidation of the soft soil are investigated. The results show that when the self-weight stress is calculated by the same method, the rate of the non-Darcian consolidation for the large-strain case is larger than that for the small-strain case, but the difference between them is limited. However, the difference between the consolidation rates caused by the non-Darcian and Darcian flows is significant. Therefore, when the geometrical nonlinearity of the soft clay is considered in calculating the consolidation settlement, due to the complexity of the large-strain assumption, the small-strain assumption can be used to replace it if the self-weight stress for the small-strain assumption is calculated by considering its sedimentation. However, due to the aforementioned large difference between the consolidation rates with consideration of the non-Darcian flow in soft clay or not, it is better to consider the non-Darcian flow law for both the small and large stain assumptions. 展开更多
关键词 LARGE-STRAIN consolidation non-Darcian FLOW NONLINEAR compression NONLINEAR PERMEABILITY
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Sintering behaviors and consolidation mechanism of high-chromium vanadium and titanium magnetite fines 被引量:6
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作者 Mi Zhou Tao Jiang +1 位作者 Song-tao Yang Xiang-xin Xue 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第9期917-925,共9页
To achieve high efficiency utilization of high-chromium vanadium-titanium magnetite (V-Ti-Cr) fines, an investigation of V Ti42r fines was conducted using a sinter pot. The chemical composition, particle parameters,... To achieve high efficiency utilization of high-chromium vanadium-titanium magnetite (V-Ti-Cr) fines, an investigation of V Ti42r fines was conducted using a sinter pot. The chemical composition, particle parameters, and granulation of V-Ti-Cr mixtures were analyzed, and the effects of sintering parameters on the sintering behaviors were investigated. The results indicated that the optimum quicklime dosage, mixture moisture, wetting time, and granulation time for V-Ti-Cr fines are 5wt%, 7.5wt%, 10 min, and 5-8 min, respectively. Meanwhile, the vertical sintering speed, yield, tumbler strength, and productivity gains were shown to be 21.28 mm/min, 60.50wt% , 58.26wt%, and 1.36 t·m^-2·h^-1, respectively. Furthermore, the consolidation mechanism of V-Ti-Cr fines was clarified, revealing that the consolidation of a V-Ti-Cr sinter requires an approximately 14vo1% calcium ferrite liquid-state, an approximately 15vo1% silicate liq- uid-state, a solid-state reaction, and the recrystallization of magnetite. Compared to an ordinary sinter, calcium ferrite content in a V-Ti-Cr sinter is lower, while the perovskite content is higher, possibly resulting in unsatisfactory sinter outcomes. 展开更多
关键词 MAGNETITE CHROMIUM VANADIUM titanium ore sintering consolidation mineralogy
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CONSOLIDATION THEORY OF UNSATURATED SOIL BASED ON THE THEORY OF MIXTURE(Ⅱ) 被引量:4
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作者 陈正汉 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第8期721-733,共13页
The present paper uses the mathematics model for consolidation of unsaturated soil developed in ref. [I] to solve boundary value problems. The analytical solutions for one-dimensional consolidation problem are gained ... The present paper uses the mathematics model for consolidation of unsaturated soil developed in ref. [I] to solve boundary value problems. The analytical solutions for one-dimensional consolidation problem are gained by making use of Laplace transform and finite Fourier transform. The displacement and the pore water pressure as well as the pore gas pressure are found from governing equations simultaneously. The theoretical formulae of coefficient and degree of consolidation are also given in the paper. With the help of the method of Galerkin Weighted Residuals, the finite element equations for two-dimensional consolidation problem are derived. A FORTRAN program named CSU8 using 8-node isoparameter element is designed. A plane strain consolidation problem is solved using the program, and some distinguishing features on consolidation of unsaturated soil and certain peculiarities on numerical analysis are revealed. These achievements make it convenient to apply the theory proposed by the author in engineering practice. 展开更多
关键词 pore water pressure pore gas pressure coefficient of consolidation degree of consolidation initial settlement finite element
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Dynamic shear modulus of undisturbed soil under different consolidation ratios and its effects on surface ground motion 被引量:8
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作者 Sun Jing Gong Maosheng Tao Xiaxin 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第4期561-568,共8页
The dynamic shear modulus for three types of undisturbed soil under different consolidation ratios is presented by using the resonant column test method. Its effects on surface ground motion is illustrated by calculat... The dynamic shear modulus for three types of undisturbed soil under different consolidation ratios is presented by using the resonant column test method. Its effects on surface ground motion is illustrated by calculation. The test results indicate that the power function is a suitable form for describing the relationship between the ratio of the maximum dynamic shear modulus due to anisotropic and isotropic consolidations and the increment of the consolidation ratio. When compared to sand, the increment of the maximum dynamic shear modulus for undisturbed soil due to anisotropic consolidation is much larger. Using a one-dimensional equivalent linearization method, the earthquake influence factor and the characteristic period of the surface acceleration are calculated for two soil layers subjected to several typical earthquake waves. The calculated results show that the difference in nonlinear properties due to different consolidation ratios is generally not very notable, but the degree of its influence on the surface acceleration spectrum is remarkable for the occurrence of strong earthquakes. When compared to isotropic consolidation, the consideration of actual anisotropic consolidation causes the characteristic period to decrease and the earthquake influence factor to increase. 展开更多
关键词 dynamic shear modulus consolidation ratio undisturbed soil resonant column test surface ground motion
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A new method for solving Biot's consolidation of a finite soil layer in the cylindrical coordinate system 被引量:5
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作者 Zhiyong Ai Quansheng Wang Chao Wu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第6期691-697,共7页
A new method is developed to solve Biot's consolidation of a finite soil layer in the cylindrical coordinate system. Based on the governing equations of Biot's consolidation and the technique of Laplace transform, F... A new method is developed to solve Biot's consolidation of a finite soil layer in the cylindrical coordinate system. Based on the governing equations of Biot's consolidation and the technique of Laplace transform, Fourier expansions and Hankel transform with respect to time t, coordinate θ and coordinate r, respectively, a relationship of displacements, stresses, excess pore water pressure and flux is established between the ground surface (z = 0) and an arbitrary depth z in the Laplace and Hankel transform domain. By referring to proper boundary conditions of the finite soil layer, the solutions for displacements, stresses, excess pore water pressure and flux of any point in the transform domain can be obtained. The actual solutions in the physical domain can be acquired by inverting the Laplace and the Hankel transforms. 展开更多
关键词 Biot's consolidation A finite soil layer Laplace transform Fourier expansions Hankel transform
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Impact of consolidation pressure on contaminant migration in clay liner 被引量:2
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作者 Zhi-hong ZHANG Zhao-gang XU +1 位作者 Xiu-li DU Hong-yan LI 《Water Science and Engineering》 EI CAS CSCD 2013年第3期340-353,共14页
Consolidation deformation occurs in clay liners under the self-weight of wastes at a simple garbage dump or dredged sediment dump, which leads to a decrease in the porosity. However. the migration of contaminants in c... Consolidation deformation occurs in clay liners under the self-weight of wastes at a simple garbage dump or dredged sediment dump, which leads to a decrease in the porosity. However. the migration of contaminants in clay liners is influenced by the porosity. Thus, the impact of consolidation deformation of clay liners on the migration of contaminants cannot be ignored. Based on Biot's consolidation theory, the contaminant migration theory, and consideration of the three kinds of migration mechanisms of convection, diffusion, and adsorption, a one-dimensional migration model of contaminants in deforming porous media was established, and the finite difference method was adopted to obtain the numerical solutions for an established initial-boundary value problem. The impact of consolidation pressure on the migration law of a contaminant was studied. The results show that, regardless of adsorption modes, different consolidation pressures have similar impacts on the migration law of the contaminant. Namely, over a certain migration time, the greater the consolidation pressure is, the smaller the migration depth of the contaminant. The results also show that, while the migration time increases, the impact of a certain increment of consolidation pressure on the variation of contaminant concentration with the depth increases gradually and, while the migration depth increases, the impact of a certain increment of consolidation pressure on the variation of the contaminant concentration with time increases gradually. 展开更多
关键词 clay liner consolidation pressure consolidation deformation. contaminantmigration
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Role of equal-strain assumption in unit-cell theory for consolidation with vertical drains 被引量:2
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作者 雷国辉 徐梨丹 +1 位作者 郑强 吴宏伟 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第12期2914-2923,共10页
In the development of unit-cell theory for the analytical analysis of consolidation with vertical drains, the equal-strain assumption is often made with the intention of modelling consolidation under uniform settlemen... In the development of unit-cell theory for the analytical analysis of consolidation with vertical drains, the equal-strain assumption is often made with the intention of modelling consolidation under uniform settlement conditions. In contrast, the free-strain assumption for modelling consolidation under uniform load conditions is seldom employed, mainly because of the complexities involved in the analysis. This study derives a rigorous analytical solution to the generalised governing equations of free-strain consolidation with a vertical drain subjected to an instantaneous load. Calculated results from the newly proposed solution are compared with those from three available solutions derived based on the equal-strain assumption. Surprisingly good agreement is obtained in terms of excess pore-water pressure, degree of consolidation, and settlement. Horizontal profiles of settlement were not uniform before the end of consolidation. This indicates that the uniform settlement condition is not actually reproduced by the analytical solutions derived based on the equal-strain assumption. The equal-strain assumption is a sufficient but not necessary condition for deriving an analytical solution to unit-cell consolidation theory. The assumption plays no role in modelling consolidation under uniform settlement conditions but simplifies the analytical analysis of free-strain consolidation and results in an approximate solution of high accuracy for consolidation under uniform load conditions. Moreover, drain resistance and smear effects not only retard the consolidation rate, but also importantly shape the vertical and horizontal profiles of excess pore-water pressure, respectively. 展开更多
关键词 consolidation ground improvement PORE pressures SETTLEMENT vertical DRAIN
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Analytical solution to one-dimensional consolidation in unsaturated soils 被引量:4
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作者 秦爱芳 陈光敬 +1 位作者 谈永卫 孙德安 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第10期1329-1340,共12页
This paper presents an analytical solution of the one-dimensional consolidation in unsaturated soil with a finite thickness under vertical loading and confinements in the lateral directions. The boundary contains the ... This paper presents an analytical solution of the one-dimensional consolidation in unsaturated soil with a finite thickness under vertical loading and confinements in the lateral directions. The boundary contains the top surface permeable to water and air and the bottom impermeable to water and air. The analytical solution is for Fredlund's one-dimensional consolidation equation in unsaturated soils. The transfer relationship between the state vectors at top surface and any depth is obtained by using the Laplace transform and Cayley-Hamilton mathematical methods to the governing equations of water and air, Darcy's law and Fick's law. Excess pore-air pressure, excess pore-water pressure and settlement in the Laplace-transformed domain are obtained by using the Laplace transform with the initial conditions and boundary conditions. By performing inverse Laplace transforms, the analytical solutions are obtained in the time domain. A typical example illustrates the consolidation characteristics of unsaturated soil from an- alytical results. Finally, comparisons between the analytical solutions and results of the finite difference method indicate that the analytical solution is correct. 展开更多
关键词 unsaturated soil one-dimensional consolidation SETTLEMENT analytical solution excess pore-air pressure excess pore-water pressure
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Evaluation of Comprehensive Benefits of Land Consolidation Based on AHP and FUZZY 被引量:5
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作者 Jinsong TIAN Jinjie TIAN Jiachun GUO 《Asian Agricultural Research》 2013年第1期17-20,26,共5页
Based on the modern comprehensive evaluation method, in accordance with the scientific, objective and systematic principles, we select four factors (economic, social, ecological and landscape benefits), to establish t... Based on the modern comprehensive evaluation method, in accordance with the scientific, objective and systematic principles, we select four factors (economic, social, ecological and landscape benefits), to establish the evaluation indicator system of comprehensive benefits of rural land consolidation. Then using the theory of fuzzy mathematics (FUZZY) and fuzzy relationship synthesis theory, we establish the fuzzy evaluation model of comprehensive benefits of land consolidation; using analytic hierarchy process (AHP), we determine the weight of each indicator, and conduct fuzzy comprehensive evaluation from various levels. By the weighted average synthesis algorithm, we calculate the evaluation indicators and finally summarize the overall evaluation results for comprehensive evaluation. Taking the case of land consolidation project in Shangyao Town, Datong District, Huainan City in Anhui Province, we calculate the case data based on Matlab software, and the calculation results and evaluation level are consistent with the project acceptance results, verifying the feasibility of this evaluation method. 展开更多
关键词 LAND consolidation COMPREHENSIVE BENEFITS ANALYTIC
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