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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 {2., Taiyuan university of technology, Taiyuan 03002., china 2. rock and Soil mechanics {2., Chinese Academy of Sciences, Wuhan 430071, china) mining technology {2. Taiyuan University of Technology Taiyuan 030024 China. rock and Soil mechanics {2. Chinese Academy of Sciences Wuhan 43007! 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.

Thermal-mechanical coupled effect on fracture mechanism and plastic characteristics of sandstone

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Science china(Technological Sciences) 2007年第6期50卷 833-843页

作者： ZUO JianPing1,2. XIE HePing2.3, ZHOU HongWei1,2.PENG SuPing1 1 State Key Laboratory of Coal Resources and Safe mining, china university of mining and technology, Beijing 100083, {2. 2.institute of rock mechanics and fractals, china university of mining and technology, Beijing 100083, {2. 3 Sichuan university, Chengdu 610065, {2. 1. State Key Laboratory of Coal Resources and Safe mining China University of Mining and Technology Beijing 100083 China 2. institute of rock {2. and fractals China University of Mining and Technology Beijing 100083 China 3. Sichuan university Chengdu 610065 China

Scanning electronic microscopy (SEM) was employed to investigate fractographs of sandstone in mine roof strata under thermal-mechanical coupled effect. Based on the evolution of sandstone surface morphology in the failure process and frac- tography, the fracture mechanism was studied and classified under meso and mi- cro scales, respectively. The differences between fractographs under different tem- peratures were examined in detail. Under high temperature, fatigue fracture and plastic deformation occurred in the fracture surface. Therefore, the temperature was manifested by these phenomena to influence strongly on micro failure mechanism of sandstone. In addition, the failure mechanism would transit from brittle failure mechanism at low temperature to coupled brittle-ductile failure mechanism at high temperature. The variation of sandstone strength under differ- ent temperature can be attributed to the occurrence of plastic deformation, fatigue fracture, and microcracking. The fatigue striations in the fracture surfaces under high temperature may be interpreted as micro fold. And the coupled effect of tem- perature and tensile stress may be another formation mechanism of micro fold in geology.

关键词： sandstone, thermal-mechanical coupled effects, fractograph, plastic deformation, SEM, micro fold

Energy analysis for damage and catastrophic failure of rocks

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Science china(Technological Sciences) 2011年第S1期54卷 199-209页

作者： XIE HePing 1,2.LI LiYun 2.1,JU Yang 2.PENG RuiDong 2.& YANG YongMing 2.1 Sichuan university,Chengdu 610065,china 2.State Key Laboratory of Coal Resources and Safe {2.,Beijing Key Laboratory of Fracture and Damage mechanics of rock and Concrete,china university of {2. and technology,Beijing 100083,china 1. Sichuan university Chengdu 610065 China 2. State Key Laboratory of Coal Resources and Safe mining Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete China University of Mining and Technology Beijing 100083 China

The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of *** main scope and the achievable objectives of the energy-based research system were *** was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy *** was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak *** both hard and soft rocks,the energy dissipated after peak load accounts for a greater *** energy would be required for rock failure under equal biaxial compression than under unequal biaxial *** total absorbed energy is different for rock failure under high-rate loading and low-rate *** fragmented failure pattern usually corresponds to higher energy *** mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt *** energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics ***,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated *** was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks.

关键词： rock deformation failure energy accumulation energy dissipation energy release

The dust emission law in the wind erosion process on soil surface

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Science china(Physics,mechanics & Astronomy) 2009年第2期52卷 258-269页

作者： XING Mao1 & GUO LieJin2.1 mining technology {2., Taiyuan university of technology, Taiyuan 03002., china 2.State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong university, Xi’an 710049, china mining technology {2. Taiyuan University of Technology Taiyuan 030024 China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an 710049 China

The dust emission models to date cannot describe the relation between the transport rate of different sized grains and their grain size composition in soil surface, so Aeolian grain transport on a soil-like bed composed of fine sand and silt powder was measured in a wind tunnel. Six types of soil-like beds with different silt fractions have been tested in this experiment. The mass flux profiles of silt dust and sand grains are much different due to their different motion modes. Analysis of the vertical distribution of the powder and sand grains reveals that for a given soil bed, the ratio of the horizontal dust flux to the horizontal sand flux is directly proportional to their mass ratio in the bed. The dust flux is closely linked to the sand flux by the bombardment mechanism. For a given wind velocity and grain size of the bed, the slopes of the vertical mass flux profiles of sand grains larger than 100 μm are nearly equal in a log-linear plot and the ratio between the fraction of transport rate of each size group to the whole transport rate and the mass fraction of each size group in the bed is a constant only dependent on grain size. With this law, the transport rate of dust and different sized grains can be related with the grain size composition in the soil surface.

关键词： wind erosion dust transport rate grain size

Comparison of Concrete Carbonation Process under Natural Condition and High CO_2.Concentration Environments

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Journal of Wuhan university of technology(Materials Science) 2010年第3期25卷 515-522页

作者：姬永生 State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology Xuzhou School of mechanics & Civil Engineering China University of Mining and Technology Xuzhou

To compare the results obtained under both natural and accelerated environments,the pH values of carbonated concrete were measured,the variation of pH values was determined,and the variations of Ca（OH）2.and CaCO3 contents in the carbonated concrete under natural condition and high CO2.concentration accelerated climate environments were determined by microcosmic test methods such as DTA and X-ray *** experimental results showed that the overall variation trend of pH values and phase component of carbonation layer of concrete under accelerated climate environments with high CO2.concentrations were the same as those under natural ***,the carbonation processes of concrete were considered consistent under both *** there was a difference in the length of semi-carbonation *** one measured under high CO2.concentration accelerated climate environments was shorter than that under natural *** investigation showed that it was caused by the differences in climate condition（temperature and relative humidity） as well as the properties of the *** concentration of CO2.and the duration of the carbonation process have no effect on the length of semi-carbonation ***,it is acceptable to simulate the natural condition by applying the high CO2.concentration artificial accelerated carbonation technique for the purpose of the study of carbonation process of concrete.

关键词： natural carbonation artificial accelerated carbonation phase component semi carbonation zone correlation

A coupled elasto-plastic-damage mechanical model for marble

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Science china(Technological Sciences) 2011年第S1期54卷 228-234页

作者： ZHOU Hui 1,ZHANG Kai 2.& FENG XiaTing 1 1 State Key Laboratory of Geomechanics and Geotechnical Engineering,institute of {2. and Soil mechanics,Chinese Academy of Sciences,Wuhan 430071,china 2.State Key Laboratory for Geomechanics and Deep Underground Engineering,china university of mining&technology,Xuzhou 2.1008,china 1. State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China 2. State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining & Technology Xuzhou 221008 China

A profound understanding of the mechanical behaviors of marble is very important for the design and construction of deep diversion tunnels in Jinping II hydropower *** this paper,a coupled elasto-plastic-damage mechanical model is presented for Jinping ***,the experimental investigations on Jinping marble are ***,based on the framework of continuum damage and plastic theories,a general mechanical model is proposed to predict the mechanical responses of Jinping *** proposed model is used to simulate the triaxial compressive tests,and there is a general good agreement between experimental data and numerical predictions in a qualitative *** proposed model is able to capture the main features of Jinping marble observed in experiments,such as progressive yielding process,damage induced by plastic distortion,dilation,elastic degradation and stress sensitivity.

关键词： mechanical model damage elasto-plastic coupling marble

Analysis on cohesive crack opening displacement considering the strain softening effect

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Science china(Physics,mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1, XU Shilang2.& ZHAO Xiqiang3 1. mechanics Department, Shandong university of {2., Zibo 2.5049, china 2. Civil Engineering Department, Dalian university of {2., Dalian 11602., china 3. Mathematics Department, Ocean university of china, Qingdao 2.6071, china mechanics Department Shandong University of Technology Zibo 255049 China Civil Engineering Department Dalian University of Technology Dalian 116024 China Mathematics Department Ocean University of China Qingdao 266071 China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

The formation mechanism of high-quality dolomite reservoir in the deep of Puguang Gas Field

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Science china Earth Sciences 2008年第S1期51卷 53-64页

作者： MA YongSheng 1 ,GUO TongLou 1 ,ZHAO XueFeng 2.&CAI XunYu 1 1 Southern Exploration&Production Company,Sinopec,Kunming 6502.0,china 2.1},Beijing 100083,china Southern Exploration & Production Company Sinopec Kunming 650200 China china university of {2. and technology Beijing 100083 China

The discovery of Puguang Gas Field provides the exploration of china deep marine carbonate rock with important *** Puguang Gas Field,the dolomite reservoirs discovered in the deep are the best in the present of china,which present big thickness and wide-range distribution,and develop abundant secondary *** researches show that Puguang Gas Field bears the characteristics of early gas-filling time,deep burial,high matured organic matter and long-term interaction of hydrocarbon(oil and gas)-water-rock(carbonate reservoir).The developments of secondary pores in this area are affected by multiple diagenesis and their formation mechanisms are *** the research on depositional environment,sedimentary facies and reservoir porosity characters of Changxing and Feixianguan Formations,it is thought that high-quality dolomite reservoirs of Puguang Gas Field form on the favorable sedimentary facies belts,which are the integrate result affected by several factors including superficial corrosion,burial corrosion,overpressure and tectonic movement,among which burial corrosion of TSR to reservoir and overpressure formed by thermal evolution of organic matter have great effect on the formation of secondary porosity of Changxing and Feixianguan Formations.

关键词： deep high-quality reservoir dolomite corrosion Puguang Gas Field Sichuan Basin

Connectivity of the Mandelbrot set for the family of renormalization transformations

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Science china Mathematics 2010年第3期53卷 849-862页

作者： WANG XiaoGuang 1,QIU WeiYuan 1 , YIN YongCheng 1 , QIAO JianYong 2.& GAO JunYang 2.1 School of Mathematical Sciences, Fudan university, Shanghai 2.0433, china 2.Center of Mathematics,{2., Beijing 100083, china 1. School of Mathematical Sciences Fudan University Shanghai 200433 China2. Center of Mathematics China University of Mining and Technology Beijing 100083 China

We show that the Mandelbrot set for the family of renormalization transformations of 2.dimensional diamond-like hierachical Potts models in statistical mechanics is connected. We also give an upper bound for the Hausd... 详细信息

关键词： connectivity Mandelbrot set renormalization transformations

Modeling of Mechanical Behavior of Fractal rock Joint

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 157-164页

作者： Jinan bang Marek A. Kwasniewski( Resources Engineering School. university of Science and technology Beijing, Bejing 100083, {2.)( rock mechanics Laboratory, Faculty of mining and Geology, Technical university of Silesia, Gliwice , Poland) Resources Engineering School University of Science and Technology Beijing Beijing 100083 China rock mechanics Laboratory Faculty of Mining and Geology Technical University of Silesia Gliwice Poland

The present study shows that naturally developed fracture surfaces in rocks display the properties of self-affine fractals. Surface roughness can be quantitatively characterized by fractal dimension D and the intercept A on the log-log plot of variance: the former describes the irregularity and the later is statistically analogues to the slopes of asperities. In order to confirm the effects of these fractalparameters on the properties and mechanical behavior of rock joints, which have been observed in experiments under both normal andshear loadings, a theoretic model of rock joint is proposed on the basis of contact mechanics. The shape of asperity at contact is assumed to have a sinusoidal form in its representative scale r, with fractal dimension D and the intercept A. The model considers different local contact mechanisms, such as elastic deformation, frictional sliding and tensile fracture of the asperity. The empirical evolution law of surface damage developed in experiment is implemented into the model to up-date geometry of asperity in loading history. The effects of surface roughness characterized by D, A and re on normal and shear deformation of rock joint have been elaborated.

关键词： fractal roughness mechanical behavior rock joints fractal dimension the intercept contact mechanics normal stiffness shear stiffness, surface damage