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Influence of Incomplete Soil Plugs on Bearing Capacities of Bucket Foundations in Clay
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作者 LI Hui-shan LIU Run +1 位作者 YANG Xu LIAN Ji-jian 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期144-155,共12页
Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be eval... Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be evaluated.In this paper,the contact ratio(the ratio of the top diameter of the soil plug to the diameter of the bucket)and the soil plug ratio(the ratio of the soil heave height to the skirt height)are defined to describe the shape and size of the incomplete soil plug.Then,finite element models are established to investigate the bearing capacities of bucket foundations with incomplete soil plugs and the influences of the contact ratios,and the soil plug ratios on the bearing capacities are analyzed.The results show that the vertical bearing capacity of bucket foundations in homogeneous soil continuously improves with the increase of the contact ratio.However,in normally consolidated soil,the vertical bearing capacity barely changes when the contact ratio is smaller than 0.75,while the bearing capacity suddenly increases when the contact ratio increases to 1 due to the change of failure mode.The contact ratio hardly affects the horizontal bearing capacity of bucket foundations.Moreover,the moment bearing capacity improves with the increase of the contact ratio for small aspect ratios,but hardly varies with increasing contact ratio for aspect ratios larger than 0.5.Consequently,the reduction coefficient method is proposed based on this analysis to calculate the bearing capacities of bucket foundations considering the influence of incomplete soil plugs.The comparison results show that the proposed reduction coefficient method can be used to evaluate the influences of incomplete soil plug on the bearing capacities of bucket foundations. 展开更多
关键词 bucket foundation incomplete soil plug uniaxial bearing capacity contact ratio soil plug ratio
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Effects of Meat and Phosphate Level on Water-Holding Capacity and Texture of Emulsion-Type Sausage During Storage 被引量:24
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作者 WANG Peng,XU Xing-lian and ZHOU Guang-hong Key Laboratory of Meat Processing and Quality Control,Ministry of Education/Nanjing Agricultural University,Nanjing 210095,P.R.China 《Agricultural Sciences in China》 CSCD 2009年第12期1475-1481,共7页
This paper was designed to verify the influence of phosphate on water-holding capacity (WHC) and texture of emulsiontype sausage prepared with pre-rigor meat, ageing meat or frozen meat. Pre-rigor pork, ageing pork ... This paper was designed to verify the influence of phosphate on water-holding capacity (WHC) and texture of emulsiontype sausage prepared with pre-rigor meat, ageing meat or frozen meat. Pre-rigor pork, ageing pork and frozen pork were pre-blended with five levels of phosphate and made into emulsion-type sausage. The yield, hardness and total expressible fluid (TEF) were measured with texture profile analysis machine and pressiometer when emulsion-type sausage was produced. Meanwhile, hardness and purge loss (PL) were measured during 30 d storage. As emusion-type sausage made by pre-rigor meat, higher yield and relatively stable hardness could be found. It indicated that increasing of phosphate level caused an alleviatable effects in increasing of hardness when emulsion-type sausage made by pre-rigor meat, but opposite effects made by ageing meat or frozen meat. The distribution of PL of emulsion-type sausage was found to be affected by phosphate addition. Significant decrease of PL could not be obtained by increasing of phosphate level during storage. Pre-rigor meat improved WHC and texture of emulsion-type sausage. Problem of WHC and texture of emulsiontype sausage during storage could not be resolved by single use of phosphate at relatively higher level (3%) of NaCl. 展开更多
关键词 MEAT emulsion-type sausage water-holding capacity TEXTURE
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The primary influence of shear band evolution on the slope bearing capacity 被引量:1
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作者 Lanting Wei Qiang Xu +1 位作者 Shanyong Wang Xu Ji 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期1023-1037,共15页
Slope bearing capacity is one of the most important characteristics in slope engineering and is strongly influenced by weak planes,loading conditions,and slope geometry.By presenting the evolution of slip surfaces,thi... Slope bearing capacity is one of the most important characteristics in slope engineering and is strongly influenced by weak planes,loading conditions,and slope geometry.By presenting the evolution of slip surfaces,this paper explored how the slope bearing capacity is affected by widely observed influencing factors.The initiation and propagation of slip surfaces are presented in laboratory model tests of slope using the transparent soil technique.Shear band evolution under various weak planes,loading conditions,and slope geometries were experimentally presented,and slope bearing capacities were analyzed with the process of shear band evolution.This paper verified that slip surface morphologies have a strong relation with the slope bearing capacity.The same slip surface morphology can have different evolutionary processes.In this case,it is the shear band evolution that determines the slope bearing capacity,not the morphology of the slip surface.The influencing factors such as pre-existing weak planes,loading conditions,and slope geometry strongly affect the slope bearing capacity as these factors govern the process of shear band evolution inside the slope. 展开更多
关键词 Slope bearing capacity Shear band evolution Failure mechanism Transparent soil
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Distribution of available soil water capacity in China 被引量:59
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作者 ZHOUWenzuo LIUGaohuan +1 位作者 PANJianjun FENGXianfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期3-12,共10页
The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for m... The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15 × 10-2 cm3·cm-3 to 22 × 10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15 × 10-2 cm3·cm-3 or higher than 22 × 10-2 cm3·cm-3. The ASWC is different according to the complex soil types and their distribution. It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The "high" values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively "high" values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively "low" values are distributed in the west and the Loess Plateau of China. The "very low" value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China. 展开更多
关键词 available soil water capacity pedo-transfer functions China
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Solid components and acid buffering capacity of soils in South China 被引量:6
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作者 Qiu Rong liang, Wu Qing, Zhang Yun ni Department of Environmental Science, Zhongshan University, Guangzhou 510275, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第2期42-48,共7页
The effects of soil solid components on soil sensitivity to acid deposition by sequential extraction method were studied. A multiple regression equation of soil sensitivity was set up on the basis of stepwise regressi... The effects of soil solid components on soil sensitivity to acid deposition by sequential extraction method were studied. A multiple regression equation of soil sensitivity was set up on the basis of stepwise regression analysis. The results showed that organic matter expressed dual effects that were decided by soil original pH value and exchangeable cation composition on acid buffering reactions. The hydrolysis of activated oxides was a very important proton buffering reaction when in low pH situation. The crystalline oxides also played a role in the buffering reactions, but the role was restricted by the rate of activation of oxides. Meanwhile, the results by stepwise analysis showed that factors that had significant effect on soil acid buffering capacity were content of montmorillite, soil original pH value, Al 0, Mn 0 and CEC in decreasing order. Finally, sixteen soils were classified into four types of sensitive with single index cluster and multiple fuzzy cluster analysis respectively. 展开更多
关键词 acid deposition acid buffering capacity soil sensitivity solid components.
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Fixed Ammonium Content and Maximum Capacity of Ammonium Fixation in Major Types of Tillage Soils in Hunan Province,China 被引量:5
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作者 ZHANG Yang-zhu HUANG Shun-hong +3 位作者 WAN Da-juan HUANG Yun-xiang ZHOU Wei-jun ZOU Ying-bin 《Agricultural Sciences in China》 CAS CSCD 2007年第4期466-474,共9页
In order to understand the status of fixed ammonium, fixed ammonium content, maximum capacity of ammonium fixation, and their influencing factors in major types of tillage soils of Hunan Province, China, were studied ... In order to understand the status of fixed ammonium, fixed ammonium content, maximum capacity of ammonium fixation, and their influencing factors in major types of tillage soils of Hunan Province, China, were studied with sampling on fields, and laboratory incubation and determination. The main results are summarized as follows: (1) Content of fixed ammonium in the tested soils varies greatly with soil use pattern and the nature of parent material. For the paddy soils, it ranges from 135.4 ± 57.4 to 412.8±32,4 mg kg^-1, with 304.7±96.7 mg kg^-1 in average; while it ranges from 59.4 to 435.7 mg kg^-1, with 230.1 ± 89.2 mg kg^-1 in average for the upland soils. The soils developed from limnic material and slate had higher fixed ammonium content than the soils developed from granite. The percentage of fixed ammonium to total N in the upland soils is always higher than that in the paddy soils. It ranges from 6.1 ±3.6% to 16.6±4.6%, with 14.0% ±5.1% in average for the paddy soils and it amounted to 5.8±2.0% to 40.1 ± 17.8%, with 23.5 ± 14.2% in average for upland soils. (2) The maximum capacity of ammonium fixation has the same trend with the fixed ammonium content in the tested soils. For all the tested soils, the percentage of recently fixed ammonium to maximum capacity of ammonium fixation is always bellow 20% and it may be due to the fact that the soils have high fertility and high saturation of ammonium-fixing site. (3) The clay content and clay composition in the tested soils are the two important factors influencing their fixed ammonium content and maximum capacity of ammonium fixation. The results showed that hydrous mica is the main 2:1 type clay mineral in 〈 0.02 mm clay of the paddy soils, and its content in 0.02-0.002 mm clay is much higher than that in 〈 0.002 mm clay of the soils. The statistical analysis showed that both the fixed ammonium content and the maximum capacity of ammonium fixation of the paddy soils were positively correlated with the total 2:1 type clay mineral content and hydrous mica content in 〈 0.02 mm clay and 0,02-0.002 mm clay at the significant level of P0.01 or P0.05, respectively, but not correlated with the total 2:1 type clay mineral content and hydrous mica content in 〈0.002 mm clay significantly, It demonstrated that the ammonium-fixing matrix of the tested soils mainly exists in the 0.02-0.002 mm clay. The above-mentioned results showed that fixed ammonium is a major form of N in the tillage soils in Hunan Province, China. It would play an important role in N nutrition of crops, especially for upland crops, and deserve to be further researched. 展开更多
关键词 Hunan Province tillage soils paddy soil upland soil fixed ammonium maximum capacity of ammonium fixation
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Acid and Alkali Buffer Capacity of Typical Fluvor-Aquic Soil in Huang-Huai-Hai Plain 被引量:11
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作者 HUANG Ping ZHANG Jia-bao +1 位作者 ZHU An-ning ZHANG Cong-zhi 《Agricultural Sciences in China》 CSCD 2009年第11期1378-1383,共6页
Soil acid and alkali buffer capacity, as a major indicator for evaluating its vulnerability and resistibility to acidification and alkalization, is an important factor affecting the sustainable agriculture, through kn... Soil acid and alkali buffer capacity, as a major indicator for evaluating its vulnerability and resistibility to acidification and alkalization, is an important factor affecting the sustainable agriculture, through knowledge on which soil acidification process can be predicted and modified. In this study, titration curve method was adopted to investigate the pH buffer capacity (pHBC) of fluvor-aquic soil, and separate titration curves were established by adding incremental amounts of either standardized hydrochloric acid (HC1) (0.12 mol L^-1) or sodium hydroxide (NaOH) (0.10 mol L^-1) to soil suspended in deionized water (soil:solution = 1:5). Soil pH was measured after 7 d resuspension and isothermal equilibrium (T = 25℃). Linear regressions were fitted to the linear portion of each titration curve and the slopes of these lines were derived as the soil pHBC. The results showed that significant correlations between the amounts of adding acid or alkali and each pH change were presented, and titration curve method was feasible for measurement of pHBC on typical fluvor-aquic soil in Huang-Huai-Hai Plain, and the coefficients of determination were higher than the similar researches on acid soil (R^2 = 0.96). The slope-derived pHBC of acid and alkali were 158.71 and 25.02 mmol kg^-1, respectively. According to the classification of soil buffer systems, the soil tested belongs to the calcium carbonate buffer system, carbonates contribute the most to pHBC, and the contribution of soil organic matter relatively less than it. 展开更多
关键词 fluvor-aquic soil Huang-Huai-Hai Plain pH buffer capacity (pHBC)
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Field Capacity in Black Soil Region, Northeast China 被引量:9
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作者 DUAN Xingwu XIE Yun +2 位作者 LIU Gang GAO Xiaofei LU Hongmei 《Chinese Geographical Science》 SCIE CSCD 2010年第5期406-413,共8页
In this work, 23 black soil profiles were surveyed and 113 soil samples were collected to determine the field capacity (FC) of the black soil in Northeast China. The effectiveness of three methods measuring FC, the Wi... In this work, 23 black soil profiles were surveyed and 113 soil samples were collected to determine the field capacity (FC) of the black soil in Northeast China. The effectiveness of three methods measuring FC, the Wilcox method (WM), the undisturbed soil pressure plate method (PUM) and the air-dried sieved soil pressure plate method (PDM) were compared to select a suitable laboratory measurement method. Results show that the FC values measured by PDM are greater than those measured by PUM, and the values measured by PUM are greater than those measured by WM. PUM is more suitable for the determination of FC in the study area. One regression equation between PUM and PDM has been established through which undisturbed soil can be replaced by air-dried sieved soil, which is easier to get, to measure FC. FCs vary from 23.50% to 37.00%, with an average of 31.65%, which differ greatly among the 23 black soil profiles. FC is found to be significantly positively correlated with the silt content, clay content and bulk density of the soil, but significantly negatively correlated with the sand content. An empirical pedotransfer function is established to estimate the FC using available soil physical and chemical properties. 展开更多
关键词 Wilcox method plate method pedotransfer function field capacity black soil
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Cokriging of Soil Cation Exchange Capacity Using the First Principal Component Derived from Soil Physico-Chemical Properties 被引量:4
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作者 LIAO Kai-hua XU Shao-hui +2 位作者 WU Ji-chun JI Shu-hua LIN Qing 《Agricultural Sciences in China》 CAS CSCD 2011年第8期1246-1253,共8页
As soil cation exchange capacity (CEC) is a vital indicator of soil quality and pollutant sequestration capacity,a study was conducted to evaluate cokriging of CEC with the principal components derived from soil phy... As soil cation exchange capacity (CEC) is a vital indicator of soil quality and pollutant sequestration capacity,a study was conducted to evaluate cokriging of CEC with the principal components derived from soil physico-chemical properties.In Qingdao,China,107 soil samples were collected.Soil CEC was estimated by using 86 soil samples for prediction and 21 soil samples for test.The first two principal components (PC1 and PC2) together explained 60.2% of the total variance of soil physico-chemical properties.The PC1 was highly correlated with CEC (r=0.76,P0.01),whereas there was no significant correlation between CEC and PC2 (r=0.03).The PC1 was then used as an auxiliary variable for the prediction of soil CEC.Mean error (ME) and root mean square error (RMSE) of kriging for the test dataset were-1.76 and 3.67 cmolc kg-1,and ME and RMSE of cokriging for the test dataset were-1.47 and 2.95 cmolc kg-1,respectively.The cross-validation R2 for the prediction dataset was 0.24 for kriging and 0.39 for cokriging.The results show that cokriging with PC1 is more reliable than kriging for spatial interpolation.In addition,principal components have the highest potential for cokriging predictions when the principal components have good correlations with the primary variables. 展开更多
关键词 soil cation exchange capacity spatial interpolation root mean square error GEOSTATISTICS
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Effects of Soluble Organic N on Evaluating Soil N-Supplying Capacity 被引量:4
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作者 LU Hong-ling LI Shi-qing +1 位作者 JIN Fa-hui SHAO Ming-an 《Agricultural Sciences in China》 CAS CSCD 2008年第7期860-870,共11页
It is important to study the soluble organic N (SON) extracted during water-logged incubation for evaluating soil Nsupplying capacity. Soil initial SON and mineral N (Nmin), cumulative soluble organic N and NH4+-... It is important to study the soluble organic N (SON) extracted during water-logged incubation for evaluating soil Nsupplying capacity. Soil initial SON and mineral N (Nmin), cumulative soluble organic N and NH4+-N in leachates during water-logged incubation, mineralization potentials of both easily decomposable N (ND) and resistant N (NR), and their relationships with N uptake by crop in pot experiment were investigated by using 10 kinds of farmland soils with widely different physical and chemical properties on the Loess Plateau, China, and the effects of SON on evaluating soil Nsupplying capacity were studied. The results showed that the average content of initial SON (23.9 mg kg^-1) of 10 soils was 28.8% of initial total soluble N and 2.4% of soil total N. The percentage of cumulative SON in leaching total soluble N (118.1 mg kg^-1 was 46.4%, higher than the percentage of initial SON (28.8%), and almost close to the percentage of cumulative NH4^+-N in the leachates. ND had close correlation with total N, and the correlation coefficients were 0.92 (P 〈 0.01, excluding SON in estimating ND) and 0.88 (P 〈 0.01, including SON in estimating ND), respectively. N mineralization potential and mineralization rate constant were different with the soil types. ND of Los-Orthic Entisols and Ust-Sandiic Entisols were lower than that of Eum-Orthrosols. Mineralization rate constant for the fast decomposable N-fraction (kD) decreased and the mineralization rate constant of resistant materials (kR) increased when SON was taken into account. Cumulative NH4^+-N was a better evaluation index of soil N-supplying capacity, and it is not only suitable for the first season crops but also for two successive season crops. Cumulative SON alone was not a satisfactory index for the potential of mineralizable N. But it would be more accurate for ND in revealing the potential mineralizable N when SON was taken into account. Cumulative TSN, to some extent, could also be taken as an index for the potential mineralizable N. Cumulative NH4+-N, total soluble N, and ND were good indexes for estimating soil potential mineralizable N, especially for soils of two successive season crops. And cumulative total soluble N and ND in evaluating the permanence of soil N-supply is of greater significance when SON was included. 展开更多
关键词 water-logged incubation N mineralization soluble organic N soil N-supplying capacity
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Ultimate Lateral Capacity of Rigid Pile in c–φ Soil 被引量:3
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作者 ZHANG Wei-min 《China Ocean Engineering》 SCIE EI CSCD 2018年第1期41-50,共10页
To date no analytical solution of the pile ultimate lateral capacity for the general c–φ soil has been obtained. In the present study, a new dimensionless embedded ratio was proposed and the analytical solutions of ... To date no analytical solution of the pile ultimate lateral capacity for the general c–φ soil has been obtained. In the present study, a new dimensionless embedded ratio was proposed and the analytical solutions of ultimate lateral capacity and rotation center of rigid pile in c–φ soils were obtained. The results showed that both the dimensionless ultimate lateral capacity and dimensionless rotation center were the univariate functions of the embedded ratio. Also,the ultimate lateral capacity in the c–φ soil was the combination of the ultimate lateral capacity(f;) in the clay, and the ultimate lateral capacity(f;) in the sand. Therefore, the Broms chart for clay, solution for clay(φ=0) put forward by Poulos and Davis, solution for sand(c=0) obtained by Petrasovits and Awad, and Kondner’s ultimate bending moment were all proven to be the special cases of the general solution in the present study. A comparison of the field and laboratory tests in 93 cases showed that the average ratios of the theoretical values to the experimental value ranged from 0.85 to 1.15. Also, the theoretical values displayed a good agreement with the test values. 展开更多
关键词 pile ultimate lateral capacity dimensionless analytical solution c–φ soils hyperbolic function method
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Seismic stability of reinforced soil walls under bearing capacity failure by pseudo-dynamic method 被引量:6
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作者 阮晓波 孙树林 《Journal of Central South University》 SCIE EI CAS 2013年第9期2593-2598,共6页
In order to evaluate the seismic stability of reinforced soil walls against bearing capacity failure,the seismic safety factor of reinforced soil walls was determined by using pseudo-dynamic method,and calculated by c... In order to evaluate the seismic stability of reinforced soil walls against bearing capacity failure,the seismic safety factor of reinforced soil walls was determined by using pseudo-dynamic method,and calculated by considering different parameters,such as horizontal and vertical seismic acceleration coefficients,ratio of reinforcement length to wall height,back fill friction angle,foundation soil friction angle,soil reinforcement interface friction angle and surcharge.The parametric study shows that the seismic safety factor increases by 24-fold when the foundation soil friction angle varies from 25°to 45°,and increases by 2-fold when the soil reinforcement interface friction angle varies from 0 to 30°.That is to say,the bigger values the foundation soil and/or soil reinforcement interface friction angles have,the safer the reinforced soil walls become in the seismic design.The results were also compared with those obtained from pseudo-static method.It is found that there is a higher value of the safety factor by the present work. 展开更多
关键词 reinforced soil walls seismic stability against bearing capacity seismic active force pseudo-dynamic method
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Variation analysis of ultimate pullout capacity of shallow horizontal strip anchor plate with 2-layer overlying soil based on nonlinear M-C failure criterion 被引量:7
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作者 ZHAO Lian-heng TAN Yi-gao +2 位作者 NIE Zhi-hong YANG Xin-ping HU Shi-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第11期2802-2818,共17页
Based on the nonlinear Mohr-Coulomb failure criterion and an associated flow rule,a kinematic admissible velocity field of failure mechanism of the 2-layer soil above a shallow horizontal strip anchor plate is constru... Based on the nonlinear Mohr-Coulomb failure criterion and an associated flow rule,a kinematic admissible velocity field of failure mechanism of the 2-layer soil above a shallow horizontal strip anchor plate is constructed.The ultimate pull-out force and its corresponding failure mechanism through the upper bound limit analysis according to a variation principle are deduced.When the 2-layer overlying soil is degraded into single-layer soil,the model of ultimate pullout force could also be degraded into the model of single-layer soil.And the comparison between results of single-layer soil variation method and those calculated by rigid limit analysis method proves the correctness of our method.Based on that,the influence of changes of geotechnical parameters on ultimate pullout forces and failure mechanism of a shallow horizontal strip anchor with the 2-layer soil above are analyzed.The results show that the ultimate pull-out force and failure mechanism of a shallow horizontal strip anchor with the 2-layer soil above are affected by the nonlinear geotechnical parameters greatly.Thus,it is very important to obtain the accurate geotechnical parameters of 2-layer soil for the evaluation of the ultimate pullout capacity of the anchor plate. 展开更多
关键词 shallow strip anchor plate 2-layer soil ultimate pullout capacity variation analysis nonlinear failure criterion
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Finite element analysis of effect of soil displacement on bearing capacity of single friction pile 被引量:3
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作者 王丽 郑刚 欧若楠 《Journal of Central South University》 SCIE EI CAS 2014年第5期2051-2058,共8页
Effect of soil displacement on friction single pile in the cases of tunneling,surcharge load and uniform soil movement was discussed in details with finite element method.Lateral displacement of the pile caused by soi... Effect of soil displacement on friction single pile in the cases of tunneling,surcharge load and uniform soil movement was discussed in details with finite element method.Lateral displacement of the pile caused by soil displacement reached about 90% of the total displacement,which means that P-Δ effect of axial load can be neglected.The maximum moment of pile decreased from 159 kN·m to 133 kN·m in the case of surcharge load when the axial load increased from 0 to the ultimate load.When deformation of pile caused by soil displacement is large,axial load applied on pile-head plays the role of reducing the maximum bending moment in concrete pile to some extent.When pile is on one side of the tunnel,soil displacements around the pile are all alike,which means that the soil pressures around the pile do not decrease during tunneling.Therefore,Q-s curve of the pile affected by tunneling is very close to that of pile in static loading test.Bearing capacities of piles influenced by surcharge load and uniform soil movement are 2480 kN and 2630 kN,respectively,which are a little greater than that of the pile in static loading test(2400 kN).Soil pressures along pile increase due to surcharge load and uniform soil movement,and so do the shaft resistances along pile,as a result,when rebars in concrete piles are enough,bearing capacity of pile affected by soil displacement increases compared with that of pile in static loading test. 展开更多
关键词 TUNNELING surcharge load uniform soil movement friction pile bearing capacity
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Influences of Soil Physical Properties on Water-Supplying Capacity 被引量:1
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作者 ZHAOBINGZI XUFUAN 《Pedosphere》 SCIE CAS CSCD 1997年第4期367-374,共8页
The water-supplying capacity of two agricultural soils, red soil in Jiangxi Province and meadow soil in Henan Province, was assessed mainly using physical investigations. The reticulated mottting horizon in the red so... The water-supplying capacity of two agricultural soils, red soil in Jiangxi Province and meadow soil in Henan Province, was assessed mainly using physical investigations. The reticulated mottting horizon in the red soil was a horizon limiting roots distribution due to its high density and hardness in structure and low pH (pH 5.05). The resistance of the red soil to drought hazard was poor because of its low water-supply capacity and poor hydraulic conductivity. The meadow soil had superior profile infiltration to that of the red soil and great available water-storage capacity) which resulted in low run-off loss, especially in the wheat-growth season. It was difficult for water stored in the deep layers of the meadow soil to reach the surface due to the low unsaturated hydraulic conductivity of its clay-rich horizon in subsoil. However, water stored in deep layers was still available because the roots could extend to the deep layers due to the relatively low density in soil structure. 展开更多
关键词 meadow soil red soil soil physical properties water-supplying capacity
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Limit analysis of ultimate uplift capacity and failure mechanism ofshallow plate anchors in multi-layered soils 被引量:1
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作者 LYU Cheng WANG Zhu-hong +1 位作者 ZENG Zheng-qiang ZHANG Xiao 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第6期2049-2061,共13页
Considering the fact that in some complex cases,plate anchors are buried in multi-layered geotechnical materials,the ultimate dynamic analysis was performed to investigate the uplift capacity and failure mechanism of ... Considering the fact that in some complex cases,plate anchors are buried in multi-layered geotechnical materials,the ultimate dynamic analysis was performed to investigate the uplift capacity and failure mechanism of shallow strips and circular plate anchors in multi-layered soils.The nonlinear strength criterion and non-associated flow rule of geotechnical materials were introduced to investigate the influence of nonuniformity on the pullout performance and failure mechanism of shallow plate anchors.The expressions of the detaching curves or surfaces were obtained to reflect the failure mechanism,which can be used to figure out the ultimate uplift capacity and failure range.The results are generally in agreement with the numerical simulations and previous research.The effects of various parameters on the ultimate uplift capacity and failure mechanism of plate anchors in multi-layered soils were investigated,and it is found that the ultimate uplift capacity and failure range of shallow anchors increase with the increase of initial cohesion and dilatancy coefficient,but decrease with the unit weight,axial tensile stress and nonlinear coefficient. 展开更多
关键词 limit analysis dilatancy coefficient ultimate uplift capacity plate anchors multi-layered soils
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Influence of varied drought types on soil conservation service within the framework of climate change:insights from the Jinghe River Basin,China
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作者 BAI Jizhou LI Jing +4 位作者 RAN Hui ZHOU Zixiang DANG Hui ZHANG Cheng YU Yuyang 《Journal of Arid Land》 SCIE CSCD 2024年第2期220-245,共26页
Severe soil erosion and drought are the two main factors affecting the ecological security of the Loess Plateau,China.Investigating the influence of drought on soil conservation service is of great importance to regio... Severe soil erosion and drought are the two main factors affecting the ecological security of the Loess Plateau,China.Investigating the influence of drought on soil conservation service is of great importance to regional environmental protection and sustainable development.However,there is little research on the coupling relationship between them.In this study,focusing on the Jinghe River Basin,China as a case study,we conducted a quantitative evaluation on meteorological,hydrological,and agricultural droughts(represented by the Standardized Precipitation Index(SPI),Standardized Runoff Index(SRI),and Standardized Soil Moisture Index(SSMI),respectively)using the Variable Infiltration Capacity(VIC)model,and quantified the soil conservation service using the Revised Universal Soil Loss Equation(RUSLE)in the historical period(2000-2019)and future period(2026-2060)under two Representative Concentration Pathways(RCPs)(RCP4.5 and RCP8.5).We further examined the influence of the three types of drought on soil conservation service at annual and seasonal scales.The NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP)dataset was used to predict and model the hydrometeorological elements in the future period under the RCP4.5 and RCP8.5 scenarios.The results showed that in the historical period,annual-scale meteorological drought exhibited the highest intensity,while seasonal-scale drought was generally weakest in autumn and most severe in summer.Drought intensity of all three types of drought will increase over the next 40 years,with a greater increase under the RCP4.5 scenario than under the RCP8.5 scenario.Furthermore,the intra-annual variation in the drought intensity of the three types of drought becomes smaller under the two future scenarios relative to the historical period(2000-2019).Soil conservation service exhibits a distribution pattern characterized by high levels in the southwest and southeast and lower levels in the north,and this pattern has remained consistent both in the historical and future periods.Over the past 20 years,the intra-annual variation indicated peak soil conservation service in summer and lowest level in winter;the total soil conservation of the Jinghe River Basin displayed an upward trend,with the total soil conservation in 2019 being 1.14 times higher than that in 2000.The most substantial impact on soil conservation service arises from annual-scale meteorological drought,which remains consistent both in the historical and future periods.Additionally,at the seasonal scale,meteorological drought exerts the highest influence on soil conservation service in winter and autumn,particularly under the RCP4.5 and RCP8.5 scenarios.Compared to the historical period,the soil conservation service in the Jinghe River Basin will be significantly more affected by drought in the future period in terms of both the affected area and the magnitude of impact.This study conducted beneficial attempts to evaluate and predict the dynamic characteristics of watershed drought and soil conservation service,as well as the response of soil conservation service to different types of drought.Clarifying the interrelationship between the two is the foundation for achieving sustainable development in a relatively arid and severely eroded area such as the Jinghe River Basin. 展开更多
关键词 meteorological drought hydrological drought agricultural drought soil conservation service Variable Infiltration capacity(VIC)model Revised Universal soil Loss Equation(RUSLE) Jinghe River Basin
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A STUDY ON BUFFERING CAPACITY OF THE FOREST SOIL AGAINST ACIDIC PRECIPITATION IN SEVERAL AREAS OF CHINA
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作者 林国珍 廖柏寒 丁茹 《Chinese Geographical Science》 SCIE CSCD 1992年第2期32-38,共7页
Soil samples from several forest areas in China were analyzed by X-ray powder diffractometry after mineral separation and enrichment. The density gradient separation method with sequential extraction by acetone-methyl... Soil samples from several forest areas in China were analyzed by X-ray powder diffractometry after mineral separation and enrichment. The density gradient separation method with sequential extraction by acetone-methylene iodide mixtures was applied for the separation of fine sand fraction of soil samples. The clay fraction (【 2μm) was separated from silt fraction of soil samples prior to examination. Mineral components in some fine sand and clay samples were compared, and their weathering potentiality and buffering capacity against acidic precipitation were discussed. 展开更多
关键词 forest soil MINERAL component ACIDIC precipitation BUFFERING capacity WEATHERING POTENTIALITY
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A distributed Grid-Xinanjiang model with integration of subgrid variability of soil storage capacity
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作者 Wei-jian Guo Chuan-hai Wang +2 位作者 Teng-fei Ma Xian-min Zeng Hai Yang 《Water Science and Engineering》 EI CAS CSCD 2016年第2期97-105,共9页
Realistic hydrological response is sensitive to the spatial variability of landscape properties. For a grid-based distributed rainfall-runoff model with a hypothesis of a uniform grid, the high-frequency information w... Realistic hydrological response is sensitive to the spatial variability of landscape properties. For a grid-based distributed rainfall-runoff model with a hypothesis of a uniform grid, the high-frequency information within a grid cell will be gradually lost as the resolution of the digital elevation model(DEM) grows coarser. Therefore, the performance of a hydrological model is usually scale-dependent. This study used the GridXinanjiang(GXAJ) model as an example to investigate the effects of subgrid variability on hydrological response at different scales. With the aim of producing a more reasonable hydrological response and spatial description of the landscape properties, a new distributed rainfall-runoff model integrating the subgrid variability(the GXAJSV model) was developed. In this model, the topographic index is used as an auxiliary variable correlated with the soil storage capacity. The incomplete beta distribution is suggested for simulating the probability distribution of the soil storage capacity within the raster grid. The Yaogu Basin in China was selected for model calibration and validation at different spatial scales.Results demonstrated that the proposed model can effectively eliminate the scale dependence of the GXAJ model and produce a more reasonable hydrological response. 展开更多
关键词 SCALE effect Subgrid VARIABILITY soil STORAGE capacity INCOMPLETE BETA distribution GXAJSV model
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Study of the Hole Wall Soil's Capacity by the Action of the Bearing Device of Rodless Drilling Rig
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作者 Wen-Wu Liu Chang-Sheng Hu +2 位作者 Nian-Li Lu Shuang-Gui Yin Ze-Yu Du 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第1期118-122,共5页
In order to ensure the bearing device of rodless drilling rig to press stably against the hole wall, it has to analyze the contact between the soil pore wall and the bearing device to study whether the soil pore will ... In order to ensure the bearing device of rodless drilling rig to press stably against the hole wall, it has to analyze the contact between the soil pore wall and the bearing device to study whether the soil pore will shear failure. This paper uses the method to calculate the additional stress of any point in soil mechanics to get the three-dimensional stress state of any point of the soil pore under the support plate, and use the numerical analysis method to calculate the shear stress and its relative intensity. Under the circumstances of maximum torque and maximum pressure, ABAQUS is used to make a finite element analysis of the capacity of the soil pore. The results of numerical analysis and FEA indicate that in the condition of the support plate will not deform; the contact area between the soil pore and the support plate is rectangular; in the force process, the soil under the ends of the support plate have the trend of yield, while it meets the condition of Mohr-Coulomb not to yield generally. 展开更多
关键词 rodless drilling rig bearing device the soil pore capacity
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