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Journal of Environmental Sciences 2004年第5期16卷 705-711页

作者： DONGXu-hui SAKAMOTOKazuhiko WANGWei GAOShi-dong ISOBEYugo Sino-JapaneseFriendshipCenterforEnvironmentalProtection Beijing100029China GraduateSchoolofScience＆Engineering SaitamaUniversity255Shimo-ohkuboUrawaSaitama338-8570Japan InstituteforEnvironmentalStudiesofChina ChongqingEnvironmentalProtectionBureau China

The bio-briquette technique which mixes coal, biomass and sulfur fixation agent and bio-briquettes under 3—5 t/cm 2 line pressure has aroused people's attention in view of controlling the air pollution and the acid rain. In this paper, the physicochemical properties of bio-briquette and its ash were investigated. And the acid soil was improved by the bio-briquette combustion ash, which contained nutritive substances such as P, N, K and had the acid-neutralizing capacity(ANC). The pH, EC, effective nutrient elements(Ca, Mg, K, P and N), heavy metal elements(Al, Cu, Cd, Cr, Zn and Mn) and acid-neutralizing capacity change of ash-added soils within the range of 0—10%, were also studied. Specially, when 5% bio-briquette combustion ash was added to the tested soil, the content of the effective elements such as Ca, Mg and K rose by 100 times, 7 times and twice, respectively. The total nitrogen also increased by about twice. The results showed the oxyanions such as that of Al, Cu, Cd, Cr, Zn and Mn were not potentially dangerous, because they were about the same as the averages of them in Chinese soil. It is shown that the ANC became stronger, though the ANC hardly increases in the ash-added soil. On the basis of the evaluation indices, it is concluded that the best mixture ratio is to add 2.5%—8% of the bio-briquette combustion ash to the tested soil.

关键词： bio-briquette combustion ash soil improvement ANC heavy metal element nutrient element

improvement of geotechnical properties of sabkha soil utilizing cement kiln dust

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 749-760页

作者： Abdullah A.Al-Homidy Mohammed H.Dahim Ahmed K.Abd El Aal Department of Civil Engineering Najran University Geology Department Faculty of ScienceAl Azhar University

improvement of properties of weak soils in terms of strength,durability and cost is the key from engineering point of *** weak soils could be stabilized using mechanical and/or chemical *** added during chemical stabilization could improve the engineering properties of treated *** utilized have to satisfy noticeable performance,durability,low price,and can be easily *** cement kiln dust(CKD) is industrial by-product,it would be a noble task if this waste material could be utilized for stabilization of sabkha *** study investigates the feasibility of utilizing CKD for improving the properties of sabkha *** samples are prepared with 2% cement and 10%,20% or 30% CKD and are tested to determine their unconfined compressive strength(UCS),soaked California bearing ratio(CBR) and *** of stabilization is studied utilizing advanced techniques,such as the scanning electron microscope(SEM),energy dispersive X-ray analysis(EDX),backscattered electron image(BEI) and X-ray diffraction analysis(XRD).It is noted that the sabkha soil mixed with 2% cement and 30% CKD could be used as a sub-base material in rigid *** incorporation of CKD leads to technical and economic benefits.

关键词： Sabkha soil Geotechnical properties soil improvement Cement kiln dust(CKD) Unconfined compressive strength(UCS) Soaked California bearing ratio(CBR) Durability

Finite Element Analysis of Effects of improvement of soil Between Double-Row Piles

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Journal of Shanghai Jiaotong university(Science) 2024年第5期29卷 919-929页

作者： NIE Dongqing ZHAI Zhiyang ZHANG Wei LI Zhi Shanghai Municipal Engineering Design General Institute(Group)Co. Ltd.Shanghai200092China Changjiang River Scientific Research Institute Wuhan430010China

Double-row pile(DRP)retaining systems have been widely used in deep excavations in *** between the front and back-row piles(FBP soil)is often improved to decrease the displacement of DRPs in soft soil areas,but the improvement efficiency has rarely been researched.A large and deep excavation supported by a DRP retaining system is introduced,and the effect of FBP soil improvement is discussed by comparing the finite element analysis and the monitoring ***,a parametric study of DRP using the finite element method considering the small strain of soil is conducted to investigate the effect of FBP soil *** was shown that the pile deflection and bending moment decrease when the FBP soil is ***,the most efficient way to minimize the pile deflection and bending moment is to improve the FBP soil around the excavation *** FBP soil improvement 2-4 m below the pile head is not very useful for reducing the pile deflection and can be eliminated when the pile displacement limit is not very strict.

关键词： large excavation double-row pile(DRP) soil improvement deflection bending moment finite element analysis

Study on improvement of Flowering Cherry soil in Nanshan Botanical Park of Chongqing City

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Agricultural Biotechnology 2020年第1期9卷 57-59页

作者： Fuyin XU Tao WAN Chongqing Landscape and Gardening Research Institute Chongqing 401329China Chongqing Urban Landscape Engineering Technology Research Center Chongqing 401329China

[Objectives] This study was conducted to analyze the current status of soil quality in Chongqing and provide scientific data for the rejuvenation of flowering cherry in the botanical park of the city. [Methods] With the flowering cherry soil in Chongqing Botanical Park as the research object, the typical soil in this area was investigated and improved. [Results] After applying soil conditioners, the pH value of the surface soil decreased from 7.32 to 6.34, and the pH value of the bottom soil decreased from 7.52 to 6.77;and the surface soil organic matter increased from 35.2 to 54.1 g/kg, and the bottom soil organic matter increased from 15.7 to 26.3 g/kg. [Conclusions] The soil has strong buffering capacity, and it is difficult to achieve rapid adjustment of soil pH and organic matter in actual work. soil improvement needs to be carried out step by step. After targeted improvement, further maintenance is required in the later stage.

关键词： Flowering cherry Organic matter Acid-base property soil improvement

Effects of Several Passivating Agents on improvement of Cd Polluted soil

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Asian Agricultural Research 2017年第10期9卷 45-48页

作者： Yuying ZHAO Yongxian LIU Zhilian FAN Yanfei HUANG Liping PAN Mengling NONG Shiyang LU Jinping CHEN Xiu LAN Guangxi University Institute of Agricultural Resource and Environment Guangxi Academy of Agricultural Sciences

Clay minerals,phosphates,alkaline materials,organic materials are common improvers in the management of Cd polluted soil. This paper systematically summarized types of common soil improvers and their passivation mechanism of Cd in soil. It reviewed advances in researches of soil improvers. Besides,it introduced major problems in four common passivating agents for management of Cd polluted soil. Finally,according to different mechanism characteristics of passivating agents,it came up with some recommendations.

关键词： Cd pollution Passivating agent soil improvement Effect

Numerical simulations of shake-table experiment for dynamic soil-pile-structure interaction in liquefi able soils

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 171-180页

作者： Tang Liang Baydaa Hussain Maula Ling Xianzhang Su Lei Key Lab of Structures Dynamic Behavior and Control(Harbin Institute of Technology) Ministry of Education School of Civil Engineering Harbin Institute of Technology

A shake-table experiment on pile foundations in liquefi able soils composed of liquefi able sand and overlying soft clay is studied. A three-dimensional(3D) effective stress fi nite element(FE) analysis is employed to simulate the experiment. A recently developed multi-surface elasto-plastic constitutive model and a fully coupled dynamic inelastic FE formulation(u-p) are used to model the liquefaction behavior of the sand. The soil domains are discretized using a solid-fl uid fully coupled(u-p) 20-8 noded brick element. The pile is simulated using beam-column elements. Upon careful calibration, very good agreement is obtained between the computed and the measured dynamic behavior of the ground and the pile. A parametric analysis is also conducted on the model to investigate the effect of pile-pinning, pile diameter, pile stiffness, ground inclination angle, superstructure mass and pile head restraints on the ground improvement. It is found that the pile foundation has a noticeable pinning effect that reduces the lateral soil displacement. It is observed that a larger pile diameter and fi xed pile head restraints contribute to decreasing the lateral pile deformation; however, a higher ground inclination angle tends to increase the lateral pile head displacements and pile stiffness, and superstructure mass seems to effectively infl uence the lateral pile displacements.

关键词： liquefaction pile pinning soil improvement pile deformation earthquake nonlinear fi nite element method shake-table experiment

Variation in glomalin in soil profiles and its association with climatic conditions,shelterbelt characteristics,and soil properties in poplar shelterbelts of Northeast China

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Journal of Forestry Research 2020年第1期31卷 279-290页

作者： Qiong Wang Wenjie Wang Zhaoliang Zhong Huimei Wang Yujie Fu Northeast Forestry University Harbin 150040People’s Republic of China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Glomalin-related soil protein(GRSP)sequesters large amounts of carbon and plays important roles in maintaining terrestrial soil ecosystem functions and ecological restoration;however,little is known about GRSP variation in 1-m soil profiles and its association with stand characteristics,soil properties,and climatic conditions,hindering GRSP-related degraded soil improvement and GRSP *** this study,we sampled soils from 1-m profiles from poplar(Populus spp.)shelterbelts in Northeast *** contents were 1.8–2.0 times higher in the upper 40 cm soil layers than at 40–100 ***-related soil organic carbon(SOC)sequestration in deeper soil layers was*1.2 times higher than in surface *** amounts of GRSP-related nutrients were similar throughout the soil profile.A redundancy analysis showed that in both surface and deeper layers,soil properties(pH,electrical conductivity,water,SOC,and soil nutrients)explained the majority of the GRSP variation(59.5–84.2%);the second-most-important factor in GRSP regulation was climatic conditions(temperature,precipitation,and altitude),while specific shelterbelt characteristics had negligible effects(soil depth and climate indirectly affected GRSP features via soil properties,as manifested by structural equation model *** findings demonstrate that GRSP is important for carbon storage in deep soils,regardless of shelterbelt *** glomalin assessments should consider these vertical patterns and possible regulating mechanisms that are related to soil properties and climatic changes.

关键词： soil depth Glomalin-related soil protein(GRSP) soil organic carbon storage Climate change soil improvement

Vegetable Production After Flooded Rice Improves soil Properties in the Red River Delta, Vietnam

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Pedosphere 2015年第1期25卷 130-139页

作者： Arij P.EVERAARTS Jacques J.NEETESON Pham T.T.HUONG Paul C.STRUIK Applied Plant Research Wageningen University and Research Centre Plant Research International Wageningen University and Research Centre Field Crop Research Institute Hai Duong and Hanoi University of Agriculture Centre for Crop Systems Analysis Wageningen University

Vegetable production in South East Asia often is in rotation with flooded rice. The puddling of the soil with flooded rice production may result in unfavourable soil conditions for the subsequent production of dry land crops. To establish whether permanent vegetable production results in favourable soil conditions for vegetables, the effects of five different permanent vegetable production systems and a system of vegetable production in rotation with flooded rice on soil properties after flooded rice were studied in a 2-year field experiment. Bulk density at 0.05–0.10 m depth layer decreased with permanent vegetable production and vegetable production in rotation with flooded rice. The decrease in bulk density was influenced by the application of organic manure and rice husks, and especially by the number of crops cultivated, suggesting that frequency of soil tillage had a major effect on bulk density. Ploughing with buffalo traction after flooded rice, in combination with construction of raised beds, could reduce or totally eliminate negative effects of puddling on soil structure. Bulk density at 0.15–0.20 m soil depth was not influenced. soil acidity decreased significantly in all systems. soil organic carbon increased in all systems, but significant increase was only found in two permanent vegetable production systems. Available phosphorus(P) significantly increased in two permanent vegetable production systems, with a positively correlation to the amount of P applied. The significant decrease in bulk density and increase in p H(H2O), after only 2 years, showed that soil conditions after flooded rice could be improved in a short time under intensive vegetable production.

关键词： available phosphorus bulk density organic carbon puddling soil fertility soil improvement

An investigation of the effects of hydrochar application rate on soil amelioration and plant growth in three diverse soils

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Biochar 2021年第3期3卷 349-365页

作者： Megan de Jager Luise Giani Carl Von Ossietzky Universität Institut Für Biologie Und UmweltwissenschaftenOldenburgGermany

The hydrothermal carbonization(HTC)of biogas digestate alters the raw materials inherent characteristics to produce a carbon(C)-rich hydrochar(HC),with an improved suitability for soil *** studies report conflicting impacts of various HC application rates on soil properties and plant *** this study,the influence of HC application rate on soil improvement and plant growth aspects was investigated in three diverse soils(Chernozem,Podzol,and Gleysol).Pot trials were conducted in which all soils were amended with 5,10,20 and 30%(w/w)HC in quintuplicate,with two controls of pure soil(with and without plants,respectively)also *** to potting,soil samples were collected from all HC-amended soils and controls and analyzed for soil pH,plant available nutrients(PO4-P and K),and microbial activity using standard laboratory and statistical *** after potting,a 6-week seed germination experiment using Chinese cabbage was conducted to determine germination success,followed by a plant growth experiment of equal duration and plant species to determine biomass *** the end of the study(after a total plant growth period of 12 weeks),each pot was sampled and comparatively analyzed for the same soil properties as at the beginning of the *** pH shifted toward the pH of the HC(6.6)in all soils over the course of the study,but was most expressed in the 20%and 30%application rates,confirming the well-documented liming effect of *** addition of HC increased the PO4-P and K contents,particularly with 20%and 30%HC *** results are proposedly due to the large labile C fraction of the HC,which is easily degradable by *** rapid decomposition of this C fraction prompted the quick release of the HCs inherently high PO4-P and K content into the soil,and in turn,further stimulated microbial activity,until this fraction was essentially *** addition did not inhibit seed germination at any rate,presumabl

关键词： Biogas digestate Hydrochar application rate soil improvement Nutrient availability Microbial activity

Numerical Analysis of the soil Compaction Degree Under Multi-Location Tamping

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Journal of Shanghai Jiaotong university(Science) 2017年第4期22卷 417-433页

作者：王威窦锦钟陈锦剑王建华 Engineering Research Center of Railway Environment Vibration and Noise of Ministry of Education East China Jiaotong University School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University

Dynamic compaction (DC) is an efficient soil improvement technique. The previous numerical studies mainly focus on the soil response of single location tamping, but ignore the soil compaction degree under multilocation tamping. In this study, a numerical investigation of multi-location tamping in granular soils is carried out using three-dimensional (3D) finite element model (FEM). The behaviors of the granular soils are described by means of the viscoplastic cap model. The constitutive relationship of the soils is implemented into LS-DYNA and is integrated with 3D FEM for numerical investigation. Then utilizing the field data from the previous studies, we investigate the soil compaction degree at different stages by a case of two basic patterns, and discuss the cause of soil response. Lastly, we evaluate the effect of construction parameters on soil compaction. The simulation results show that the previous tamping affects the soil compaction degree beneath the adjacent tamping location, and the effect is greater near the side of previous location. Meanwhile, the soil compaction degree around the existing tamping crater weakens due to the adjacent tamping. Moreover, the rational selection of DC construction parameters can improve the soil compaction degree, and some hints on the effect of soil compaction are given. © 2017, Shanghai Jiaotong University and Springer-Verlag GmbH Germany.

关键词： dynamic compaction(DC) soil improvement multi-tamping locations finite elements plastic volumetric strain