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2003, 22 (10): -0 doi:
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[PDF 119 KB] (678)

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TESTING STUDY ON FATIGUE DEFORMATION LAW OF ROCK
UNDER CYCLIC LOADING

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2003, 22 (10): -1581 doi:
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[PDF 563 KB] (1828)

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Testing study is made on the fatigue failure and deformation mechanism of sandstone and marble under uniaxial compression condition with rock mechanics test equipment RMT-150B. Testing result shows that the fatigue failure curve is controlled by complete stress-strain curve under static loading. The terminal strain of fatigue failure is equal to that of post-peak corresponding to the maximal cyclic load. The development of irreversible deformation can be divided into three phases，that is，initial phase，uniform velocity phase and accelerated phase. The accumulative deformation at three stages will lead to the final failure. The amplitude and maximum of cyclic load are the most important effect factors on fatigue lifespan of rock.

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SOME DEVELOPMENTS OF PRINCIPLES FOR CONSTRUCTION PROCESS MECHANICS AND SOME CASE HISTORY STUDIES

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2003, 22 (10): -1586 doi:
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[PDF 426 KB] (1365)

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The principles of construction process mechanics，energy transformation of surrounding rock and support，and time-space effect of construction have been developed and explained. Some case history studies of time-space effect for construction process for the tunnels or caverns of Jinchan Nickel Mining，Huainan Coal Mining，Xiaolangdi Hydro-electric Project are presented.

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STUDY ON METHODOLOGY OF COMPREHENSIVE INTELLIGENT ANALYSIS AND OPTIMUM DESIGN FOR LANDSLIDE

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2003, 22 (10): -1592 doi:
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[PDF 228 KB] (1034)

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Considering the highly nonlinear mechanical problem affected by many factors，the integration of intelligence，global optimum and determined mechanics is very attractive to analysis and control design of landslide. The state-of-the-art of the study results on monitoring，intelligent prediction，analysis and optimum design of landslide is presented，including integrated intelligent analysis and optimum design methodology，support vector machine of displacement time series，back analysis of mechanical parameters using evolutionary support vector machine-finite element method，optimum design of reinforcement of landslide using evolutionary neural network-numerical method，and their applications to stability analysis and optimum design of highway slopes and large Three Gorges reservoir slopes. The results indicate that the suggested methodology is scientific and applicable. At the end，the development future on this topic is also discussed.

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STUDY ON ENGINEERING GEOLOGY INFORMATION MANAGEMENT AND VISUALIZATION OF HANJIAYA SLOPE IN WUHAN—SHIYAN HIGHWAY

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2003, 22 (10): -1597 doi:
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[PDF 230 KB] (1046)

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Based on field data of Hanjiaya slope in Wuhan—Shiyan highway，the engineering geology database is set up for scientific management. Digital elevation model (DEM) is built by geometry interpolation of discrete points. Highway and slope are cut in DEM by algebraic operation with different models. Stability calculation for Hanjiaya slide and potential slide through the foot is carried out on the sections formed by DEM. The presented study results are of guidance significance to similar projects.

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FURTHER VERIFICATION OF TIME-TEMPERATURE EQUIVALENCE FOR GRANITE

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2003, 22 (10): -1601 doi:
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[PDF 468 KB] (1007)

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At first，creep properties of granite are studied which are related to time，temperature，stress level and rock composition，through analyses on the test data from 20 to 400℃ collected from the international journals. Then the equivalent effects between time and temperature on rock creep are investigated at different stress levels. Furthermore，the shift factor in time coordinate is calculated and the main curves are formed.

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PREDICTION AND CONTROL OF ROCKBURST DURING DEEP EXCAVATION OF A GOLD MINE IN CHINA*

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2003, 22 (10): -1607 doi:
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[PDF 1059 KB] (1940)

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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.

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3D GEOSTRESS REGRESSION ANALYSIS METHOD AND ITS APPLICATION

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2003, 22 (10): -1613 doi:
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[PDF 242 KB] (1387)

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Initial geostress is one of the most important factors in geotechnical design and construction. According to in situ measurement，with 3D FEM regression analysis used，considering the gravity and con-
structional stresses of rock mass，and by using multivariate regression analysis principle，the initial stress field of the calculation area can be obtained. The geostress regression analysis results of a highway tunnel indicate that the calculated results are in a good agreement with the in situ measured data and can be used to engineering practice.

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STUDY ON GENETIC-SUPPORT VECTOR MACHINE IN
DISPLACEMENT BACK ANALYSIS

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2003, 22 (10): -1618 doi:
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[PDF 255 KB] (1067)

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An evolutionary support vector machine for displacement back analysis is proposed by combining the support vector machine and genetic algorithm. The learning and testing samples produced in orthogonal and equality experiment are used to train the support vector machine whose parameter is determined in global optimal by genetic algorithm. Thus，the support vector machine with optimal parameter is used to describe the relationship between the rock mechanics parameters and displacements. Then genetic algorithm is adopted again to search for the optimal rock mechanics parameters in their global ranges. As an example，a back analysis for elastic and elasto-plastic problem is introduced. The results are satisfactory.

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OPTIMIZATION OF THE CONSTRUCTION SEQUENCE AND ANCHORING PARAMETERS IN THE LARGE UNDERGROUND CAVERN EXCAVATION OF SHUIBUYA PROJECT

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2003, 22 (10): -1623 doi:
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[PDF 542 KB] (992)

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The large underground main powerhouse of Shuibuya water conservancy project is located at interlacing of soft rock and hard rock，and the stability of the cavern will have significance for safe operation of the hydropower station. 3D nonlinear FEM numerical simulations considering of different construction steps and anchoring parameters have been performed. Comparising the numerical results，the optimal scheme of construction sequence and anchorage parameters of the cavern is suggested，and this scheme can keep the stability of cavern well.

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3D FEM ANALYSIS ON GROUND SURFACE DEFORMATION CAUSED BY MINING UNDER THICK ROCK OVERBURDEN

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2003, 22 (10): -1629 doi:
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[PDF 453 KB] (933)

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The analysis of 3D elasto-plastic FEM is introduced for calculating the deformation of the ground surface caused by underground mining under thick rock overburden.

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FLUID-SOLID COUPLING FEM CALCULATION FOR DOUBLE POROSITY ROCK MATERIAL DEPENDENT ON STRAIN CONDITION

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2003, 22 (10): -1636 doi:
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[PDF 240 KB] (938)

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Based on the double porosity concept，an approach is presented to derive a set of coupled differential equations governing behavior of porous fissured media. The finite element technique and code are employed for the solution of these equations by using Galerkin FEM. The relations，relating rock classification rating RQD and RMR，are developed to define the changes of effective porosity and hydraulic conductivity that result from the redistribution of strains in disturbed rock mass. At last，a hypothetical example is presented，and the obtained results are compared to these of the previous work.

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STUDY ON PARALLEL EVOLUTIONARY NEURAL NETWORK FEM ON STABILITY AND OPTIMIZATION FOR LARGE CAVERN GROUPS——
PART Ⅱ：CASE STUDY

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2003, 22 (10): -1640 doi:
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[PDF 389 KB] (781)

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A case history study on replacement scheme optimization and stability analysis of soft rock mass at a Shuibuya underground power house is presented using the proposed parallel evolutionary neural network FEM. The results indicate that the presented methodology is superior in global searching and quick convergence. The case history study gives the optimum replacement scheme and replacement steps. Through the comparison between the FEM and neural network calculation of the optimum scheme，the methodology is tested to be reasonable. Meanwhile，the rational suggestion is proposed to guide the construction.

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PHYSICAL SIMULATION OF WATER-OIL MICROCOSMIC FLOW THROUGH FRACTURED POROUS MEDIA

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2003, 22 (10): -1646 doi:
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[PDF 335 KB] (1424)

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Using microcosmic glass-slice model，the two-phase fluid (oil and water) flow in fractured porous media is studied. Six different fractured models are studied. By observing the fluid flow in the models，some beneficial conclusions are obtained and they are significant to understand the fluid flow in fractured porous media.

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STUDY ON SEEPAGE CHARACTERISTICS OF A SINGLE
ROCK FRACTURE UNDER SHEAR STRESSES

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2003, 22 (10): -1651 doi:
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[PDF 309 KB] (1374)

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The results of experiments of seepage characteristics of a single rock fracture under shear stresses are presented. The experimental arrangement permitted shear stress to be obtained without causing displacement of the two fracture surfaces，so that their original geometry is retained. Tests show that fracture water flow conforms to the Darcy′s law，i. e.，flow quantity is lineal with water pressure. With shear stress increasing，the mean aperture and permeability of fracture decrease lineally，and the relationship between shear stress and seepage characteristic is verified theoretically. Compared with the phases during and after dilation，it has shown that the shear stress slightly affects the seepage characteristics.

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EVOLVING CELLULAR AUTOMATA FOR SIMULATING
ROCK FAILURE

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2003, 22 (10): -1656 doi:
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[PDF 287 KB] (1062)

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Based on the theory of the physical cellular automata (PCA) and genetic algorithm，an evolving cellular automata is put forward. When rock failure is simulated with PCA，the energy dissipative rate has to be chosen artificially. This model makes use of genetic algorithm to search for the fittest energy dissipative rate with the stress-strain curve. And it can simulate the homogeneity and the anisotropy of the rock conveniently. So if a stress-strain curve is given，its corresponding energy dissipative rate can be attained with this model and it demonstrates that the rock will show more plasticity with the increase of the energy dissipative rate.

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CATASTROPHE MODEL OF CRACK PROPAGATING IN BOLT-SUPPORTED JOINTED ROCKMASS

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2003, 22 (10): -1661 doi:
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[PDF 719 KB] (947)

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In order to see into stability of rock mass during crack propagation，and the fracture toughness increment of crack by bolt which will prevent propagation of crack，the relationship of shear strength of bolted joint plane and bolting parameters in compressive-shear stress state is set up. Furthermore，sub-crack propagation mechanics model is developed on the basis of catastrophe theory，which is significant for understanding crack propagation process，assessing stability of rockmass，and taking reasonable bolting measures in advance.

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STRENGTH BEHAVIOR OF ROCKMASS CONTAINING COPLANAR CLOSE INTERMITTENT JOINTS UNDER DIRECT SHEAR CONDITION

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2003, 22 (10): -1667 doi:
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[PDF 310 KB] (1026)

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On the basis of model testing results，the deformation and fracture mechanism of brittle rockmass containing coplanar close intermittent joints under direct shear condition are analyzed，and the criteria of fracture initiation strength and failure strength of such rockmass are proposed. The calculated results fit in well with experimental results，which indicates that the criteria are reasonable and reliable.

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UNIAXIAL EXPERIMENTAL STUDY ON RHEOLOGICAL PROPERTIES OF GRANITE IN AIR-DRIED AND SATURATED STATES

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2003, 22 (10): -1673 doi:
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[PDF 210 KB] (1039)

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A lot of experimental studies have been made on the rheological properties of soft rocks. Compared with this fact，only a very small quantity of studies have been done on that of hard and integrate rocks. The influence of rheological properties of hard and integrate rocks on geotechnical engineering can be omitted in many cases. However，the influence may be great enough so that it can not be omitted when hard and integrate rocks are in a very bad environment for a long time，for example，submerged in a saturated state. Therefore，the study of rheological properties of hard and integrate rocks is of great significance in a very bad environment. In this paper，rheological experimental study of granite is done in a saturated state，and comparison is made with that of air-dried state. Important data are obtained about strength and deformation properties of granite in the given condition.

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CONSTITUTIVE RELATIONSHIP OF DEEP SALT ROCK AND
ITS APPLICATION TO PETROLEUM DRILLING ENGINEERING

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2003, 22 (10): -1678 doi:
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[PDF 271 KB] (1344)

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Based on the experimental results of the creep for deep salt rock in site，the creep properties of salt rock are investigated and the law of creep is analyzed. The equation of 3D steady creep strain rate is given. The optimized drilling mud densities is suggested with figures obtained by FLAC3D code.

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STUDY ON CONSTITUTIVE RELATION OF ROCK UNDER DYNAMIC COMPRESSION BASED ON ENERGY BALANCE DURING CRACK GROWTH

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2003, 22 (10): -1683 doi:
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[PDF 335 KB] (926)

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Based on the sliding crack model and energy balance during crack growth，the dynamic constitutive relation of rock under different strain rates is established. It is shown that the simulation results agree well with experimental results. The properties of the non-linear strain caused by the crack growth are also studied. It is indicated that the non-linear axial strain caused by the crack growth is larger than that of lateral strain. In addition，the contribution of the non-linear strain caused by the initial crack sliding cannot be ignored.

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INFLUENCE ANALYSIS OF TRANSDUCER IN IMPACT-ECHO METHOD
BASED ON LTI SYSTEM THEORY

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2003, 22 (10): -1689 doi:
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[PDF 337 KB] (967)

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The dynamic procedure of an ideal free pile with a shock force impacting at its top is mathematically simulated by means of one-dimensional wave equation. The theoretic time history of velocity response without considering transducer at the top of pile is calculated with FEM program. The frequency-domain descriptions of the shock force and the velocity response are given out through convolution integral and Fourier transform of LTI system. According to the LTI system theory，an analysis is made on the dynamic procedure with considering transducer behavior and the frequency-domain description of velocity response is obtained. The digital frequency-domain combination of a typical transducer behavior with the velocity response of ideal free pile without considering transducer is turned back into a time history of velocity response，so that the transducer behavior can be considered through Fourier back transform. Calibrating shock duration and calculating the velocity responses from a certain transducer，the law of combination influence of shock force with transducer on the velocity response is developed and validated with examples. A new type of transform-domain suppressing method is put forward at last，so that the influence of transducer behavior within velocity response can be suppressed by means of a computation program possibly.

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TESTING ON PHYSICAL AND MECHANICAL
PROPERTIES OF HORIZONTAL JET-GROUTED SOILCRETE

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2003, 22 (10): -1695 doi:
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[PDF 200 KB] (1071)

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The physical and mechanical property indices of horizontal jet-grouted soilcretes，such as unconfined compressive strength，tensile strength, compressive modulus，softened coefficient of compressive strength，cohesion，friction angle and so on，are obtained through many experiments in the laboratory. The relationship among unconfined compressive strength，tensile strength，and compressive modulus is discussed.

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RESEARCH ON ANCHORING AND SHEARING
EFFECT OF ANCHORING CABLE

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2003, 22 (10): -1699 doi:
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[PDF 293 KB] (1159)

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Testing research is made in laboratory on anchoring mechanism of anchoring cable in jointed rockmass. The shear character of cable under different fixing angle and different roughness of joint plane is simulated in the test. At the same time，in order to furtherly investigate the loading mechanism of anchoring cable，some strain gauges are arranged on the different positions of cable，so that the strain of cable is obtained under different loading steps. The testing results provide some useful conclusions.

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

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2003, 22 (10): -1704 doi:
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[PDF 227 KB] (9356)

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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.

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PARAMETRIC VARIATION PRINCIPLE OF ELASTO-PLASTIC LARGE DEFORMATION IN BIOT′S CONSOLIDATION THEORY

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2003, 22 (10): -1716 doi:
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[PDF 427 KB] (1598)

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Based on updated Lagrangian formulation of elasto-plastic large deformation theory，the numerical simulation method of Biot′s consolidation theory on elasto-plastic large deformation is developed using the idea of parametric variation principle. The advantages of this method are to convert elasto-plastic analysis into finding out the minimum of elasto-plastic potential energy with constrains of yield condition and avoid elasto-plastic iteration at every load step. Furthermore，this method can solve the problems of non-associate flow and stress softening of elasto-plasticity.

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STUDY ON GEOLOGICAL MODELING IN 3D STRATA VISUALIZATION

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2003, 22 (10): -1722 doi:
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[PDF 238 KB] (1615)

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The strata are usually irregularly curved surfaces and can not be expressed mathematically. According to the features of strata and based on the ideas of digital elevation model (DEM)，the method of multi-layer DEM is put forward，and the fitting function of strata surface is established. The result of the application shows that the approach here is practicable and effective in 3D stratum modeling. Some visual functions for real 3D strata are implemented，such as rotating，moving，zooming，layer displaying and dividing section freely.

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RANDOM SLOPE STABILITY ANALYSIS BY UPPER BOUND APPROACH

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2003, 22 (10): -1727 doi:
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[PDF 194 KB] (948)

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A new method for slope probability analysis in soils and rocks is presented，based on slope stability analysis by upper bound approach. According to the disturbing principle，the random variable expression of limit load is derived. And then the partial derivative is worked out by utilizing the continuous fraction method. Finally，the optimal approximation in quadratic norm method is made to obtain the value of the slope reliability. The results show that the new method is accurate and efficient.

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PRELIMINARY INVESTIGATION ON THE REACTIVATION OF MAOPING LANDSLIDE，GEHEYAN RESERVOIR，QINGJIANG RIVER

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2003, 22 (10): -1730 doi:
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[PDF 560 KB] (1093)

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Based upon the analysis of monitored data，such as precipitation，reservoir level fluctuation and deformation，etc. from 1993 to 2000，preliminary conclusion is reached that the reactivation of Maoping landslide is caused by the irrational coal mining in the Baiyan cliff to the east of the landslide. Coal mining-induced cliff rock cracking and collapse enhanced hydraulic connection between the landslide and the cliff，indirectly increased the precipitation area of the landslide. So the landslide deformation is greatly influenced by precipitation，especially intensive precipitation. Reservoir impounding and water level fluctuation mainly influence the deformation of the toe area.

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STUDY ON PORE WATER PRESSURE AND DEFORMATION OF
SOFT CLAY COMPACTED WITH DYNAMIC CONSOLIDATION BY DRAINAGE

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2003, 22 (10): -1738 doi:
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[PDF 267 KB] (1224)

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According to the experimental data of soft clay foundation treated with dynamic consolidation by drainage，the laws of pore water pressure and deformation of saturated soft clay under dynamic loading are discussed. The relation between the excess pore water pressure dissipation and vertical settlement incresement is founded. These discussions provide some useful conclusions for study on the principle of soft clay compacted with dynamic consolidation by drainage，and it is significant to engineering projects.

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NON-DETERMINACY ANALYSIS OF PHASE IN SASW TESTING

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2003, 22 (10): -1742 doi:
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[PDF 1673 KB] (959)

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Because of the effect of higher modes of surface waves and the distance between two receivers，it is very difficult to calculate absolute phase differences from the wrapped phase curve given in frequency domain by the conventional unwrapped technique. The difference between the absolute and the wrapped phases is 2p by an integer for each frequency point. The phase velocities calculated from a wrapped phase are varied with the integer， which do not correspond to the phase velocities of modes respectively. When the influences of different mode surface waves are separated in frequency domain，the dispersion curves of modes can be obtained in the corresponding frequency zones by the non-determinacy analysis of phase. Of these curves，one always corresponds to the so-called‘measured phase velocity vs frequency’ curve. When all curves of phase velocity for each distance are overlapped and the overlapped probabilities are figured by brightness，the dispersion curves of the fundamental mode and higher mode waves can be distinguished from brightness variation.

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APPLICATION OF ARTIFICIAL SANDS IN SHOTCRETE SUPPORT
OF TUNNEL

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2003, 22 (10): -1749 doi:
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[PDF 233 KB] (1200)

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Artificial sand is the generalization of machine-made sand and mixed sand，and has been widely used in construction，mining and irrigation works in the region of scarcity of natural sand. One kind of artificial sands，machine-made sand，has been used in shotcrete supporting for Gushan tunnel of Jiaojin thruway，He′nan province. Based on the testing and practice results of this project，the physical properties of artificial sands and feasibilities to replace natural sands with artificial sands in three aspects of technology，economy and implementation for shotcrete support of tunnel are studied. The results show that the proposed technique is feasible，thrifty and reliable，so that it merits popularization.

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EROSION OF RUBBISH LEACHATE ON ROCK AND SOIL AND INFLUENCE ON THEIR MECHANICAL PROPERTIES

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2003, 22 (10): -1753 doi:
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[PDF 150 KB] (940)

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The erosion mechanism is presented of rubbish leachate on the rock and soil from chemical point of view. The influence of rubbish leachate is also analyzed on the mechanical properties of rock and soil，such as internal cohesion and internal friction angle.

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2003, 22 (10): -1756 doi:
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[PDF 185 KB] (1382)

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STUDY OF STABILITY AND OPTIMIZATION OF LARGE CAVERN GROUP USING SYNTHETIC INTEGRATED INTELLIGENT METHOD

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2003, 22 (10): -1760 doi:
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[PDF 90 KB] (815)

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