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Progress in Natural Science:Materials International 2005年第8期15卷 742-748页

作者： LIANG Weiguo 1,2* and ZHAO Yangsheng1(1. Mining Technology institute, Taiyuan University of Technology, Taiyuan 030024, china 2. rock and soil mechanics institute, chinese academy of sciences, wuhan 43.071, china) Mining Technology institute Taiyuan University of Technology Taiyuan 030024 China rock and soil mechanics institute Chinese Academy of Sciences Wuhan 430071 China

The hydraulic fracture in rock salt is a complicated solid fluid and mass transfer coupling process. Through theoretical analysis, a solid fluid and mass transfer coupling mathematical model of hydraulic fracture in rock salt is established in this work, and numerical simulations are carried out with the model. The simulation results indicate that rock salt cracks in the typical way of wing-crack(or tensile crack) during the fracture, and the relation of fracture aperture (w) with expanding distance (x) and fracture time (t) is w=(0.0034+0.0006t)e (0.0007+0.0018t)x. Furthermore, it has been found that both the water pressure in the crack and the expanding velocity of the crack decrease gradually as a result of the influence of salt dissolving during fracturing. These numerical simulations well illustrate the process of hydraulic fracture in rock salt and are significantly meaningful in engineering practice.

关键词： rock salt hydraulic fracture solid liquid and mass transfer coupling mathematical model numerical simulation.

Modified Mohr-Coulomb strength criterion considering rock mass intrinsic material strength factorization

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Mining Science and Technology 2010年第5期20卷 701-706页

作者： ZHANG Qiang,WANG Shuilin,GE Xiurun,WANG Hongying State Key Laboratory of Geomechanics and Geotechnical Engineering,institute of rock and soil mechanics,chinese academy of sciences,wuhan 43.071,china State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China

With the increase of mining depth of mineral resources,the rock mass stress state is being more and more *** rock mass show different features,namely,with the increase of hydrostatic pressure,rock mass failure mode turns from brittle tension failure to structure ductile failure and its limit strength also *** restriction of minimal principal stress on the initiation and development of microcrack and the change of micro-unit stress state by the intermediate principal stress play a decisive role in the increase of rock mass limit *** on the rock mass failure behavior law under complex stress state and the σ2-dependence on the rock mass strength,we proposed a Modified Mohr-Coulomb(M-MC) strength criterion which is smooth and ***,the M-MC criterion is validated by multiaxial test data of eight kinds of rock *** also compared the fitting results with Mohr-Coulomb criterion(MC).It shows that the new criterion fits the test data better than the Mohr-Coulomb *** the M-MC strength criterion well reveals the rock mass bearing behavior and can be widely used in the rock mass strength *** results can provide theoretical foundations for stability analysis and reinforcement design of complex underground engineering.

关键词： rock mass strength criterion Mohr-Coulomb criterion multiaxial test failure mode underground engineering

MESHLESS METHOD OF DUAL RECIPROCITY HYBRID RADIAL BOUNDARY NODE METHOD FOR ELASTICITY

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Acta Mechanica Solida Sinica 2010年第5期23卷 447-458页

作者： Fei Yan Xiating Feng Hui Zhou 1(State Key Laboratory of Geomechanics and Geotechnical Engineering,institute of rock and soil mechanics,chinese academy of Science,wuhan 43.071,china) State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Science Wuhan China

Combining the radial point interpolation method （RPIM）, the dual reciprocity method （DRM） and the hybrid boundary node method （HBNM）, a dual reciprocity hybrid radial boundary node method （DHRBNM） is proposed for linear elasticity. Compared to DHBNM, RPIM is exploited to replace the moving least square （MLS） in DHRBNM, and it gets rid of the deficiency of MLS approximation, in which shape functions lack the delta function property, the boundary condition can not be applied easily and directly and it＇s computational expense is high. Besides, different approximate functions are discussed in DRM to get the interpolation property, in which the accuracy and efficiency for different basis functions are compared. Then RPIM is also applied in DRM to replace the conical function interpolation, which can greatly improve the accuracy of the present method. To demonstrate the effectiveness of the present method, DHBNM is applied for comparison, and some numerical examples of 2-D elasticity problems show that the present method is much more effective than DHBNM.

关键词： meshless method hybrid boundary node method dual reciprocity method radial point interpolation method elasticity

Virtual multi-dimensional internal bonds model and its application in simulation of rock mass

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Science china(Technological sciences) 2008年第2期51卷 192-201页

作者： ZHANG ZhenNan1,2 & GE XiuRun3,4 1 Department of Civil Engineering,Shanghai University,Shanghai 200072,china 2 Shanghai institute of Applied Mathematics and mechanics,Shanghai University,Shanghai 200072, china 3 institute of Geotechnical Engineering,Shanghai Jiao Tong University,Shanghai 200030,china 4 institute of rock and soil mechanics,chinese academy of sciences,wuhan 43.071,china Department of Civil Engineering Shanghai University Shanghai China Shanghai institute of Applied Mathematics and mechanics Shanghai University Shanghai China institute of Geotechnical Engineering Shanghai Jiao Tong University Shanghai China institute of rock and soil mechanics Chinese Academy of Sciences Wuhan China

VMIB (virtual multi-dimensional internal bonds) is a multiscale mechanical model developed from the VIB (virtual internal bond) theory. In VIB theory,the solid mate-rial is considered to consist of random-distributed material particles in microscale. These particles are connected with normal bonds. The macro constitutive relation is derived from the cohesive law between particles. However,in VMIB,the micro particles are connected with both normal and shear bonds. The macro constitutive relation is derived in terms of bond stiffness coefficients. It has been theoretically certified that there exists a corresponding relationship between the two bond stiffness coefficients and the two macro material constants,i.e. the Young’s modulus and Poisson ratio. This corresponding relationship suggests that it should be necessary and sufficient to simultaneously account for the normal and shear interactions between particles. Due to the fact that the fracture criterion is directly incorporated into the constitutive relation,both VIB and VMIB present many advantages in simulating fractures of materials. In the damage model of rock mass,a damage tensor is usually defined to describe the distribution of cracks. The damage value in one direction determines the relative stiffness of rock mass in this direction. In VMIB solid,the relative distribution density of micro bonds in one direction determines the relative macro stiffness of the material in this direction. The effects of the damage value and the relative distribution density of bonds are consistent. To simulate the failure behavior of rock mass with VMIB,the presented paper sets up a quantitative relationship between the damage tensor and the rela-tive distribution density of bonds. Comparison of the theoretical and the experi-mental results shows that VMIB model can represent the effect of distributed cracks on rock mass with this relationship. The presented work provides a founda-tion for further simulating fracture behavior

关键词： VMIB (virtual multi-dimensional internal bonds) rock mass VIB (virtual internal bonds) multi-cracked body numerical simulation

NUMERICAL MODELING FOR COUPLED THERMO-HYDRO-MECHANICAL AND CHEMICAL PROCESSES (THMC) OF GEOLOGICAL MEDIA——INTERNATIONAL AND chinese EXPERIENCES

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岩石力学与工程学报 2003年第10期22卷 1704-1715页

作者： Jing Lanru,Feng Xiating (institute of rock and soil mechanics,The chinese academy of sciences, wuhan 43.071 china) Inst. of rock and soil Mech. The Chinese Acad. of Sci. Wuhan 430071 China

The coupled thermo-hydro-mechanical and chemical (THMC) processes of stress/deformation,fluid flow,temperature and geochemical reactions of the geological media,namely fractured rocks and soils,play an important role in design,construction,operation and environmental impact assessments of rock and soil engineering works such as underground nuclear waste repositories,oil/gas production and storage,geothermal energy extraction,landslides and slope stability,hydropower and water conservancy complexes,etc. This paper presents an overview of the international and chinese experiences in numerical modeling of the coupled THMC processes for both the state-of-the-knowledge,remaining challenges and possible future prospects.

关键词：地质力学化学耦合反应数值模拟国外

Theory and practice concerning classification for expansive soils using standard moisture absorption water content

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Science china(Technological sciences) 2005年第1期48卷 31-40页

作者： YAO Hailin1, CHENG Ping2, YANG Yang1 & WU Wanping2 1. institute of rock and soil mechanics, chinese academy of sciences, wuhan 43.071, china 2. china Communications Second Highway Survey Design and Research institute, wuhan 430052, china institute of rock and soil mechanics Chinese Academy of Sciences Wuhan China china Communications Second Highway Survey Design and Research institute Wuhan China

A series of tests on physical, mechanical and chemical properties of expansive soils have shown that the standard moisture absorption water content (SMA) of expansive soils has a good linear relationship with montmorillonite content, cation exchange capacity, specific surface, and it also presents a linear relationship tendency to plastic index and free swell ratio. All this indicates that the above SMA is of clear significance in physics. The plastic index can better reflect the interaction extent between composition and dispersing character of grains, cation and clay minerals. Consequently, SMA can reflect the basic essential properties of expansive soils. On the basis of the classification results that have been published in literature and in consideration of the succession to the classification results for the free swell ratio, this paper puts forward three indexes, i.e. the SMA, plastic index and free swell ratio to classify expansive soils. The tests proposed for the classification indexes are easy to operate, simple in testing device and last a short time. Compared with the latest issued “Classification Standard Code for rocks and soils of Railway Projects” (TB10077-2001), the method proposed in this paper is more convenient and reasonable, and can be popularized, when environment conditions ripen, for the application in field of exploration and design of highway in the areas surrounded by expansive soils.

关键词： expansive soil, standard moisture absorption water content (SMA), plasticity index, free expansive ratio, identification and classification of expansive soils.

Effects of chlorothalonil and carbendazim on nitrification and denitrification in soils

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Journal of Environmental sciences 2009年第4期21卷 458-467页

作者： LANG Man, CAI Zucong State Key Laboratory of soil and Sustainable Agriculture, institute of soil Science, chinese academy of sciences,Nanjing 210008, china State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

The effects of chlorothalonil and carbendazim on nitrification and denitrification in six soils in upland and rice paddy environments were investigated. Laboratory aerobic （60% water holding capacity） and anaerobic （flooded） conditions were studied at 25℃ and fungicide addition rates of 5.5 mg/kg A. I. （field rate, FR）, 20 times （20FR） and 40 times （40FR） field rate, respectively. The results indicated that chlorothalonil at the field rate had a slight inhibitory effect on one soil only, and that soil did not nitrify much in the first place. But chlorothalonil at higher rates inhibited nitrification significantly in all soils. For soils JXP and JXU with a pH of less than 5.0, chlorothalonil almost completely stopped their nitrification at 20FR and 40FR during the whole 14 d incubation period. For soils HNP and HNU with a pH of greater than 8.0, chlorothalonil also significantly inhibit nitrification at 20FR and 40FR （p 〈 0.05）. However, NH4＋ that was added to the soil was also almost completely nitrified by the end of the incubation period in these two soils. The effects of chlorothalonil at 20FR and 40FR on the nitrification of JSP and JSU soils, with a pH of 5.4 and 7.2, respectively, were intermediate between the other soil types. Chlorothalonil had no effect on denitrification at the field rate and had little effect at the higher rates of application in some soils. Carbendazim had essentially no effect on nitrification and denitrification in soils assessed.

关键词： fungicide nitrification denitrification chlorothalonil carbendazim

3D thermo-hydro-mechanical-migratory coupling model and FEM analyses for dual-porosity medium

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Science china(Technological sciences) 2010年第8期53卷 2172-2182页

作者： ZHANG YuJun 1&ZHANG WeiQing 2 1 State Key Laboratory of Geomechanics and Geotechnical Engineering,institute of rock and soil mechanics, chinese academy of sciences,wuhan 43.071,china 2School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,china State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China School of Civil Engineering Southwest Jiaotong University Chengdu China

One kind of 3D coupled thermo-hydro-mechanical-migratory model for saturated-unsaturated dual-porosity medium was established,in which the stress field and the temperature field are single,but the seepage field and the concentration field are double,and the influences of sets,spaces,angles,continuity ratios,stiffness of fractures on the constitutive relationship of the medium can be *** relative three-dimensional program of finite element method was also *** comparing with the existing computation example,reliability of the model and the program were *** a hypothetical nuclear waste repository as a calculation example,the radioactive nuclide leak was simulated numerically with both the rock mass and the buffer being unsaturated media,and the temperatures,negative pore pressures,flow velocities,nuclide concentrations and normal stresses in the rock mass were *** results showed that the temperatures,negative pore pressures and nuclide concentrations in the buffer all present nonlinear changes and distributions that even though the saturation degree in porosity is only about 1/9 of that in fracture,the flow velocity of underground water in fracture is about 6 times of that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity,and that the regions of stress concentration occur at the vicinity of two sides of the boundary between buffer and disposal pit wall.

关键词： dual-porosity medium thermo-hydro-mechanical-migratory coupling three-dimensional model FEM analysis

PREDICTION AND CONTROL OF rockBURST DURING DEEP EXCAVATION OF A GOLD MINE IN china

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岩石力学与工程学报 2003年第10期22卷 1607-1612页

作者： Zhang Guang,Chen Jingxi,Hu Bin (institute of rock and soil mechanics,The chinese academy of sciences, wuhan 43.071 china) institute of rock and soil mechanics The Chinese Academy of Sciences Wuhan 430071

The studies of prediction and control of rockburst are presented during deep excavation in a gold mine in china. Firstly,the stress-relief method is used to obtain a vast amount of data about initial geostress. Secondly,3D FEM analyses of large scale are performed to find out the law of geostress distribution at various excavation levels of the mining area. At the same time,as an equally important measure,six typical kinds of rock blocks are sampled for the experimental study of rockburst tendency. According to the synthesized results of the theoretical and testing results,the methods of brittleness coefficient,brittle index and stress,and so on,are adopted. Finally,the evaluation on the possibility of rockbursts is given that may take place at the deep mining area and some effective measures are put forward to prevent and control the rockburst.

关键词：中国金矿开挖岩爆预报控制

Quantitative Relationship Between Land Use and Phosphorus Discharge in Subtropical Hilly Regions of china

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Pedosphere 2003年第1期13卷 67-74页

作者： YANG JINLING and ZHANG GANLINinstitute of soil Science, the chinese academy of sciences, Nanjing 210008 (china) institute of soil Science the Chinese Academy of Sciences Nanjing 210008

The increase of phosphorus concentration is a crucial factor causing the eutrophication of water body,while land use has an important impact on agricultural non-point sources (NPS) phosphorus discharge. Sevensites controlling the water in four sub-watersheds and the main exit of the Meicun Watershed of XuanchengCounty, Anhui Province, were investigated by dynamic monitoring of stream water and nutrient discharge,integrating interpretation of aerial image and GIS analysis to find out how the land use affects phosphorusloss with stream water in typical agriculture-forest watershed in subtropical china. These monitored sitesare different in structure of land use. Phosphorus concentration of the stream water was analyzed everyweek and at the next day of rainfall. The velocity of flow was measured by kinemometer to calculatethe runoff flux and phosphorus discharge. The results showed that the runoff flux and the discharges ofdissolved phosphorus (DP), particle-associated phosphorus (PAP) and total phosphorus (TP) had significantexponential relationships with the area percentages of forest, pond and paddy field. There existed a significantlinear relationship between the TP and PAP concentrations in stream water and the area percentages of forest,pond and paddy field, and the discharge of PAP was also significantly linearly correlated with the dischargeof suspended soil particles. There was a logarithmic linear relationship between DP and PAP discharges. Thestudy indicated that the adjustment of land use patterns and construction of ecologically sound landscapewould be an important measure to reduce the runoff discharge of phosphorus. The results would be veryuseful in building the best management practices (BMPs) of agricultural watershed in subtropics.

关键词： land use phosphorus runoff watershed