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2005, 24 (11): -0 doi:
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2005-11期目录

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STUDY ON PROCESSING METHOD OF DRILLING DATA FOR THREE-DIMENSIONAL MODELING OF ENGINEERING ROCK MASS

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2005, 24 (11): -1821 doi:
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A vast data from the drilling and geophysical prospecting are reliable original data to describe the space state of engineering rock mass，and one of the main difficulties in three-dimensional(3D) modeling of engineering rock mass is the processing of the primary data. In the view of 3D modeling，the engineering rock masses are classified as four basic types according to their geometric characteristics of geologic structure：(1) continuous rock mass；(2) discontinuous rock mass；(3) adverse fold rock mass；and (4) unstratified rock mass. Drilling data are the important data for rock mass description with the characters of multi-scale of the spatial data，and thus the criteria of processing drilling data is established. According to the characteristics of rock layers，the processing method of drilling data for 3D modeling of engineering rock mass is proposed，which includes vertical generalizing rule and layered method of processing generalizing rule for original drilling data. With this method，the data for 3D modeling of engineering rock mass is performed and the model form of engineering rock mass is established. Consequently，3D modeling of engineering rock mass is proposed；and the feasibility of this method is proved to be successful.

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SIMULATED EXPERIMENT STUDY ON THE TEMPERATURE FIELD OF FROZEN SUBGRADE MODULATED BY HORIZONTAL PIPES

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2005, 24 (11): -1827 doi:
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In permafrost regions，the construction of railway should keep the subgrade frozen permanently so as to maintain the stability of the frozen subgrade. The main factors that influence the temperature field of the frozen subgrade are presented. Using the self-made experimental equipment for simulating frozen subgrade which is supported by horizontal pipes placed in the embankment，two means of maintaining frozen subgrade are simulated in the laboratory. One method is controlling natural cold energy only，and the other is controlling natural cold energy accompanied with artificial refrigeration simultaneously. The experimental results indicate that the subgrade temperature can not go down below 0 ℃ until at least 2 years after completion when only using natural cold energy in winter，but it can be below 0 ℃ at the completion of construction when using natural cold energy in winter and artificial refrigeration in summer. The advantages of sufficiently using natural cold energy can gradually emerge after 2 years. However，the superiority of using artificial refrigeration becomes weaken after 4 years.

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ELECTRICAL EFFECT OF ROCK STRESS AND ITS FRACTURE EVOLUTION LAWS

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2005, 24 (11): -1832 doi:
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The basic laws of electrical conduction by ions for rocks and the measuring methods of pulse non-polarization for electrical current are studied. The theoretical relation between the rate of electrical resistance and that of porosity for rocks is explained. The study on the electrical effects of limestone and sandstone containing NaCl solution under compressive stress is presented with the method of combining mechanics and electricity. The experimental facility is established and the complete experimental data of stress-strain-electrical resistance of rocks are achieved. The experimental results indicate that the electrical resistance variation of rock fluctuates with the variation of the internal fissures of rock. There is a minimum value for electrical resistance of rock in all electrical resistance-strain curves，by which the cracking stress of rocks can be justified and defined. In the process of rock fracture，there is a clear anti-symmetry between the change law of stress-strain curve and that of electrical resistance. Based on the experimental study and the stochastic property analysis of rock fracture variation，the equations of stress-strain-electrical resistance in sections are proposed with a new distinguishing feature，by which the regular stress of rocks and the remnant stress can be described. The complicated fracture characteristic of rocks can also be displayed clearly by the electrical resistance of rocks. It further verifies the associated state equations with rock compression through fitting the calculated results of the experimental data for limestone and sandstone，which can be used to reveal the evolution laws of rock fracture.

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EFFECT EVALUATION OF DISTORTION FOR NORTH PROJECT OF SIDE SLOPE IN FUSHUN WEST OPEN CAST

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2005, 24 (11): -1841 doi:
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By investigating the influence of hydraulic pressure on the deformation of north side slope of Fushun open cast，the slide and inclination deformation mechanism of high steep slope in the area W200-W600 are presented，as well as the evaluation of effect of reinforcement for anti-slide pile and dewatering. The results show that most of the maximum deformation appears in layers No.1 and No.2，and the deformation decreases greatly after being reinforced. Otherwise，the slide depth will get into layer No.5 and this will lead to the slide of the whole layer No.5. Finally，some practice effects are introduced and it can provide references to the prediction and control of failure and instability of the similar slopes.

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CHARACTERISTICS OF SKEMPTON COEFFICIENT OF REPRESENTATIVE ROCK AND SOIL

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2005, 24 (11): -1847 doi:
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The fundamental characteristics of Skempton coefficient have been studied based on the theoretical analyses and laboratory under the undrainage. Some tests have been performed under the different conditions，for instance，different confining pressures and different loading types. The mechanism of Skempton coefficient change has also been investigated. That the compressibility of water cannot be neglected is proposed for the calculation of civil engineering. It is very important for the research of mechanical properties of rock mass and soil mass in the Three Gorges reservoir，and in the construction of dam foundation and embankment.

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STATISTICAL CONSTITUTIVE MODEL OF SANDSTONE SUBJECTED TO HYDROCHLORIC ACID ATTACK

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2005, 24 (11): -1852 doi:
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Based on the fact that calcium carbonate(CaCO3) is dissolved and the pore is expanded in the calcareous cementitious sandstone subjected to hydrochloric acid attack；and the strength of corroded rock has the characteristics of random distribution. The method to describe rock heterogeneity is proposed by in terms of Weibull distribution function and the nonlinear elastic constitutive equation of the corroded rock is established. The homogeneity coefficient is evaluated by means of nondestructive X-ray CT scanning technique. The results indicate that the acid environment has strong influence on mechanical properties of rock.

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STUDY ON SURROUNDING ROCK STABILITY OF DEEP MINING IN KAILUAN MINING GROUP

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2005, 24 (11): -1857 doi:
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Based on the observation and numerical simulation of roadway failure in deep mining，it is found that the horizontal tectonic stress is much greater than the original vertical rock stress and the in-situ stress is beyond the strength of rock surrounding roadway in Kailuan mining area. Thus，the large deformation of roadway and catastrophic floor heave are deemed to be inevitable. With the increasing of mining depth，coal bumps become more severe and violent. Translatory coal bumps are the main dynamic hazards in deep mining of Kailuan mining group，which have different mechanism compared to the rock bursts happened in hard rock under large-scale in-situ stress. Furthermore，it is noticed that the fracture zone of surrounding roadway is mainly influenced by the in-situ stress. However，the roadway shape has little effects on the fracture zone of surrounding roadway.

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EXPERIMENTAL STUDY ON MECHANICAL CHARACTER OF SANDSTONE OF THE UPPER PLANK OF COAL BED UNDER HIGH TEMPERATURE

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2005, 24 (11): -1863 doi:
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The mechanical experiment of 44 sandstone specimens in the sixth mine of Hebi under high temperature and after high temperature is introduced；and the regularities on the strength and deformation character with temperature varying are proposed. The results show that peak-value strength，elastic modulus，and deformation modulus of sandstone under high temperature and after high temperature are gradually decreased with general similar variation tendency. The elastic parameters of some specimens are higher than those under common temperature. Compared with both of them，the peak-value strength，elastic modulus，and deformation modulus of sandstone after high temperature increase by a little and they are all brittle fractures. The results provide experimental basis for stability of surrounding rock when heat exits in the place of firing and variation regularity of strain field and displacement field.

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INFLUENCE ON DIFFERENT OVERBURDEN SOILS DUE TO BEDROCK FRACTURE

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2005, 24 (11): -1868 doi:
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By means of the geotechnical centrifuge technology，the four different overburden soils are studied by simulating vertical and horizontal faults，whose maximum bedrock offsets are 4.5 and 3.3 m，respectively. The results show that：(1) when bedrock fracture occurs，the influence range inside overburden soils produced by vertical fault (down fault) is greater than that produced by horizontal fault (strike slip fault)；(2) the influence degree inside single middle strength soft soil is greater than that inside the cross bedding¢s sedimentary soils composed of coarse and fine grained soil layers；and (3) under way of bedrock offset 1-3 m，the fracture inside overburden soils appears and all fracture heights are less than 20 m. When the bedrock offset becomes great enough to 4.5 m，the fracture expands inside overburden soils but the fracture heights are all within 30 m. It shows that the centrifuge test results have significant references to both the evaluation of countermeasure against faults in engineering practice and the revisions of some design regulations.

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NUMERICAL SIMULATION ON DAMPING EFFECT OF IMPACTED ROOF AND ITS ANALYSIS WITH CHAOTIC DYNAMICS THEORY

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2005, 24 (11): -1875 doi:
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Based on numerical results of impacted roof movement at four stages which have been verified in-situ，the damping effects of roof movement at the impacted stage with three-dimensional distinct element code and chaotic dynamics theory are studied. With the increase of damping degree，the impact of roof movement decreases obviously and its damping inflection is at the point of 0.8. Meanwhile，the states of the system evolve from chaos to ordered steady state and then to chaos again. Index of chaotic degree shows that the system will develop towards the ordered and stable states with improvement of damping level，which can even change movement of impacted roof from initial active mode to passive mode. If the area of hanging impacted roof is large enough，measures to prevent rock burst may improve damping level of the system and change movement of the hard roof from impacted mode to periodic mode.

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STUDY AND APPLICATION OF COUPLING BETWEEN EME AND STRESS IN ELECTRO-MAGNETICAL EMISSION PREDICTION TECHNOLOGY FOR COAL OR ROCK DYNAMICAL DISASTER

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2005, 24 (11): -1881 doi:
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The present situation and progress trend of electro-magnetic emission(EME)prediction technology for rock or coal dynamical disasters are analyzed. On the basis of the relationship between EME signal and loading stress during deformation and fracture of coal or rock，the coupling methods between EME and stress are studied based on FLAC simulation for stress field and EME propagation. The results show that the coupling relationship can be expressed by thrice multinomial approximately. The electromagnetic emission signal will increase with the increase of loading stress，which approximately conforms to thrice multinomial. There are relatively large influences on the EME intensity or pulse in loading stress and loading speed. The higher the stress and loading speed are，the stronger the signal of electromagnetic emission produced is. The coupling results of calculation show that the EME signals increase with the increment of loading speed or the strength of coal or rock. The coupling method between EME and stress based on FLAC analogy can reliably ascertain the stress concentration fields，and properly simulate the distribution rules of EME signal in coal or rock stratum. It provides a kind of new approach to electromagnetic emission monitoring technology for the purpose of the application of monitoring EME to the prediction of dynamical disaster phenomena such as coal or rock outbursts. It can also provide reliably theoretical basis for the use of EME method and technology to predict and forecast rock or coal dynamical disasters. It has important meaning for perfecting the EME monitoring and detecting theory and promoting the related disciplines. Finally，a prospect for the research on the EME prediction technology for rock or coal dynamical disaster in the future is presented.

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MESHLESS NATURAL NEIGHBOR METHOD AND ITS APPLICATION TO COMPLEX GEOTECHNICAL ENGINEERING

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2005, 24 (11): -1888 doi:
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The meshless natural neighbor method(MNNM)，which is based on the Laplace interpolations and similar to the element-free Galerkin method(EFG)，is presented to solve the problems of geotechnical engineering. The discrete model of the domain W consists of a set of distinct nodes and a polygonal description of the boundary. In stead of searching for the natural neighbors from Delaunay triangulation of the whole domain in natural element method(NEM) or natural neighbor method(NNM)，the MNNM quantifies the natural neighbor nodes of the given point based on the local Delaunay triangles. The interpolation scheme used in MNNM is Laplace interpolation. The properties of the Laplace interpolation are excellent. The conditions of linear consistency，partition of unity，positivity，and delta property are all satisfied in this interpolation scheme. The difficulties of the imposition of essential boundary conditions，the treatment of material discontinuities，and the arbitrary choice of weight functions encountered in EFG method have been avoided. The proposed MNNM is true meshless similar to EFG for all the numerical procedures are automatically accomplished by the computer，and it possesses both the excellent properties of the natural neighbor interpolation and advantages of the EFG method. Application of the method to various problems，which include the cantilever beam and the complex geotechnical engineering problems，are presented. Numerical results indicate that the theory and programs are accurate and effective.

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NUMERICAL SIMULATION STUDY ON THE HIGH-PRESSURE WATER INJECTION INTO COAL SEAM IN MUCHENGJIAN COAL MINE

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2005, 24 (11): -1895 doi:
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The previous water injection into coal seam was applied when the tunnel was excavated in order to solve the rockburst problem in Muchengjian coal mine. The single drilling hole isobaric water injection was put into effect on site in 6178 excavation working face of this coal mine and the water increment around the drilling hole was measured. Then the model parameter was inversed by using variable-tolerance-band optimization search method and the water transmission and storage characteristic parameters were obtained，which showed that this coal seam has bad water transmissibility and belongs to low-wetted saturation，so the high-pressure water injection is suitable for the coal mine. The dynamic changing processes of water injection under 7.0 MPa are described by visual numerical simulation in detail. The dynamic variable relation among pressure-time-wetted perimeter of water injection was formulated by numerical simulation trial in the end.

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FRACTURE MECHANICS PRINCIPLES OF ANCHORAGE FOR LAYERED ROCK MASS SLOPE

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2005, 24 (11): -1900 doi:
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The anchorage and stability of rock mass slopes are the difficult problems in the field of geotechnical engineering. Better calculation methods for anchorage effect in rock mass slope have not been found for a long time. The latent weak interfaces of interlayer in layered rock mass are equivalent to iso-interval collinear in multi-joint model. Based on the linear elastic fracture mechanics，the changes of the stress fields near joint line by anchoring have been analyzed from the finite dimension element of rock mass containing a joint loaded by pressures and shear forces. The formulas of anchor effect by anchoring are proposed and the problems of stability improvement by anchoring in anchored rock mass slope are considered comprehensively.

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ANALYSIS OF THREE-DIMENSIONAL SIMULATION OF CASING STRESS IN LOOSE SANDSTONE RESERVOIR

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2005, 24 (11): -1905 doi:
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Along with the exploration of oil-field in the medium and late terms，the problem of the casing damage which is resulted from the reservoir of loose sandstone is becoming the focus of the study. The sand production has become a serious problem that influences well productivity and damaging production equipment. According to real properties of oil field，the sand production mechanism of the reservoir of the loose sandstone is discussed and 3D finite element model of casing-cement sheath-formation is established. An elasto-plastic constitutive model is utilized on the basis of Mohr-Coulomb yield surface. The model，based on the finite element method，is used to discuss the changing of the sand production position and its surroundings，and the changing of the casing stress where the perforated wellbore is located when the sand production changes under the given parameters. The results indicate that the casing stress condition changes greatly with well depth and the sand production quantity. The study provides the basis for the research of the casing failure mechanism and controlling measure of the loosen sandstone reservoirs.

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STUDY ON THE WEATHERED DAMAGE ATTRIBUTES OF ROCK AND THE LAW OF REDUCTION FOR COAL COLUMN PROTECTION

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2005, 24 (11): -1911 doi:
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Based on a large number of experimental data，in-situ observations and mining engineering practice on a large-scale reduction for coal column protection in weathered zone，the distributed characteristics of the weathered zone of bedrock in covered coal field are studied. The weathered rocks have a series of variational characteristics such as the decreased intension，increased plasticity deformation，muddy tendency，easily combined fractures，greatly boosted water resistance，and strong hydrophilicity and so on. The characteristics of engineering geology，which mainly cover the new movement evolution characteristics of overburden damage mining in weathered zone such as fast movement，large deformation，quick contraction and compression，and great subsidence，are studied with some new understandings，such as the rocks in weathered zone mainly composed of argillaceous rocks that have the dual functions of water blockage and water flowing prevention in fractured zone from development with mining influence. The thickness and the weathered degree of coal column are the main factors affecting the height development of flowing fractured zone and so on. The mining mechanism of reduction for the coal column protection is studied. A series of new measures of key techniques are proposed to guarantee extraction safe for the first time such as lagged controlling water in exhausted workings，distribution of coal and water，the height increase of extraction，geophysical prediction，and pre-reinforcement of geological fractures and so on. It has important theoretical application for the reclamation and safe mining in shallow resources of similar coal mines.

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STUDY ON THE NUMERICAL INTEGRATION SCHEME WITH NATURAL ELEMENT METHOD

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2005, 24 (11): -1917 doi:
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In natural element method(NEM)，the trial and test function are constructed with the natural neighbor interpolation(NNT) method. The interpolation is constructed with respect to the Voronoi tessellation of the scattered nodes in the problem domain. The integration of the weak form is performed in the Delaunay triangles，which is the dual diagram of the Voronoi tessellation when the Galerkin method is used to form the discrete system equation. But the integration domain does not align with the compacted support of the NEM shape function，which results in considerable integration error. The partition of unity quadrature method which employs the fact that the meshless shape function possesses the partition of unity is presented，and the integration can be done within the compacted support of the shape function. However，the shape and the size of NEM shape function are determined by the Voronoi tessellation and are somewhat complex. Therefore，the implementation of partition of unity quadrature in NEM involves the decomposition and mapping the support of NEM shape function. A single point quadrature rule is proposed based on the average strain of each Delaunay triangle，the average strain can be calculated by shift surface integral to contour integral via the divergence theorem，thus the derivatives of the shape function are unnecessary to form the global stiffness matrix. Numerical examples show both the accuracy and efficiency are improved. Considering both the accuracy and the efficiency，the point quadrature based on the average strain of Delaunay triangle is a better selection，though its convergence and accuracy are a little lower than the partition of unity quadrature method.

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STUDY ON TREATMENT SCHEME OF NANZHU LANDSLIDE IN FENGDU COUNTY

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2005, 24 (11): -1925 doi:
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Based on the geological exploration of Nanzhu landslide，the stability analysis of the landslide is studied when the water level of the Yangtze River falls from 175 m to 125 m. The results show that the landslide will be unstable under this condition. As a result，treatment needs to be carried out. Compared with a pair of treatment schemes，it is found that the anti-slide pile scheme is reasonable. Moreover，a new design method of anti-slide pile and the calculation code are achieved；and it is verified by the centrifugal model test. Finally，the optimal treatment scheme and additional engineering measures are proposed.

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SLOPE STABILITY ANALYSIS USING MONTE CARLO TECHNIQUE WITH FEM

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2005, 24 (11): -1933 doi:
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The Monte Carlo method combined with the elastoplastic finite element method(FEM) is proposed to analyze the slope stability problems. The factor of safety is calculated with the aid of stress fields and the pore pressure field obtained from the finite element analysis. The trial slip surfaces are verified frequently by the random walking method and gradually tend to the critical slip surface. The global minimum factor of safety can be found by comparing the results of a number of trial slip surfaces. The proposed method can solve the problems of falling into local minima，which most regular optimization methods are prone to be，by the random search methods. On the other side，the proposed method can also consider the influence of the change of stress fields and pore pressure field on the minimum factor of safety by the finite element analysis. Numerical examples are analyzed to show the feasibility of the proposed method.

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STUDY ON ULTIMATE BEARING CAPACITY OF SOFT SANDY GRAVEL ROCK FOUNDATION

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2005, 24 (11): -1942 doi:
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The method to calculate the ultimate bearing capacity of soft sandy gravel rock foundation is established based on Hoek-Brown strength criterion. In order to study its ultimate bearing capacity，the shear failure model is suggested；and the formulas for calculation normal stress levels on potential failure surface are ascertained. Combined with in-situ loading test of a certain hydraulic project，the bearing capacity of soft sandy gravel rock foundation and the effect of dead load stress on the bearing capacity are discussed. The calculation results show：(1) the method covers shortage which is difficult to obtain peak value of load at load-settlement curve due to the field test condition；(2) the calculation ultimate bearing capacity is greater than design intending load，which indicate that the strength of soft sandy gravel rock can satisfy the demand of the project；(3) the rational design footing load has a minor effect on ultimate bearing capacity，which is very important for obtaining normal stress on potential failure surface；(4) the dead load stress has apparent effect on ultimate bearing capacity；and (5) the difference between solutions of Hoek-Brown and Bell on ultimate bearing capacity is comparatively small. The analysis results provide new reference to the study of bearing capacity of this type in soft sandy gravel rock foundation.

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NUMERICAL STUDY ON OPTIMUM GRAIN-DIAMETER FOR THE CRUSHED ROCK EMBANKMENT OF QINGHAI—TIBET RAILWAY

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2005, 24 (11): -1947 doi:
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The crushed rock embankment can provide cool energy for the permafrost beneath it and guarantee the stability of permafrost without thawing. The cooling effects of the crushed rock embankment are already seen to be verified by in-situ data. However，the mechanism is still to be explored and the design parameters also need to be optimized. The heat transfer in crushed rock railway embankment could be treated as the air convection problem in porous media. Here，the local thermal equilibrium is assumed to exist between the air and the grains；and the air is expressed by the Boussinesque approximation. The heat transfer equations，the motion equation，and the conservation equation are achieved with finite element formulas of Galerkin¢s method；and then，a program 3G2003 to simulate the heat transfer in crushed rock embankment is developed. Simulations are performed on the crushed rock roadbeds composed of crushed rock with diameters of 3，6，9 and 15 cm，respectively. The results shows that the 9 cm-crushed rock embankment has the best cooling effect，which will cause a decrease of 1.18 ℃ in the temperature at the base of embankment；and air convection occurs in entire interior embankment. The temperature field shows prominent nonlinear characteristics，and the average air speed at the bottom of embankment is 0.73 m/h. The embankment composed of crushed rock of 6 cm in diameter will induce a decrease of 0.78 ℃ in temperature，accompanied by weak air convection with air speed of 0.21 m/h at the base of embankment. The embankments consisting of 3 cm and 15 cm diameter crushed rock have poor cooling effect，which will have 0.21 ℃ and 0.28 ℃ decrease in temperature，respectively，where air speed at the bottom approximate zero. Therefore，the 9 cm diameter crushed rock is recommended for the construction of Qinghai—Tibet railway so that permafrost embankment can be protected.

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STUDY ON SOIL-PILE-RAFT INTERACTION WITH CONSIDERATION OF SOIL CONSOLIDATION AND RHEOLOGY

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2005, 24 (11): -1954 doi:
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The soil-pile-raft interaction problem with consideration of soil rheology is studied by Biot consolidation theory and integral equation method. By using integral transform methods，the fundamental solutions of ring load on the surface of the half space are established. The second kind of Fredholm integral equation of the pile-soil-raft interaction problem is obtained by using fundamental solutions and the pile-soil and raft-soil deformation compatibility condition. The integral equation can be simplified by means of Laplace transforms methods. By the numerical solution of the integral equation and the corresponding inverse integral transforms，the displacement，axial force，pore pressure along the pile axis，and the contact normal stress between raft and soil，are obtained.

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STUDY ON THE VISUALIZATION ANALYSIS OF SOIL MECHANICAL PARAMETERS DISTURBED DURING CONSTRUCTION

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2005, 24 (11): -1960 doi:
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Underground project implementation is a large-scale dynamic system complicated with site condition and undefined property of rock and soil involved therein. Therefore，it brings much difficulty upon the analysis. In allusion to specific project implementation schemes and existing problems for excavation work，and based on the analysis of visualization for scientific computing，a visual data analysis method for soil mechanical parameters disturbed by construction is proposed with an algorithm of volume visualization by setting up an analytical approach of visualization to the mechanical parameters change of disturbed soil that is caused by project implementation. A proposed solution for the realization of visual expression in mechanical parameters for disturbed soil during project implementation，i. e.，V，volume visualization of voxel-based rendering (direct volume rendering)，has been applied to the analysis of visualization of soil mechanical parameters disturbed by project implementation. Volume data set contains soil mechanical parameters outside foundation pit and 3D data of displacement field，i. e.，volume data set V that is a high dimensional vector field to be employed for visualization analysis of various construction parameters in various construction stages. A direct volume rendering method of excavation data analysis about anchor-abutment of Runyang bridge constructed by freezing excavation method is studied and some unusual problems have been found by visualization analysis of soil mechanical parameters disturbed by construction process. Volume data set of excavation work and the 3D structure have been set up. Almost all soil mechanical parameters and soil displacement fields have been involved in this volume data. The soil behavior at anytime of excavation stages is discussed. A complete visualization analysis system of soil mechanical parameters disturbed by project implementation is given for the purpose of studying the whole processes of soil mechanical parameters disturbed by project implementation during excavation with visualization analysis method. Practical application shows that launching of visualization analysis method into underground construction project is very imminent with significant results and it builds up a graphics linkage between man and data instead of written text or numerical tabulation.

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A MODEL FOR DESCRIBING THE NONLINEAR CONSOLIDATION CHARACTERISTICS OF SATURATED SOFT SOIL

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2005, 24 (11): -1966 doi:
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Based on the nonlinear governing equation for one-dimensional primary consolidation and its dimensionless forms，an analytical consolidation theory of saturated soft soils is deduced. The relationship between void ratio and effective stress is assumed by previous studies. By using the initial and boundary conditions，the analytical expressions of normalized void ratio of normally consolidated saturated soils for uniform surcharge loading and two-way drainage are presented. The degrees of consolidation are also given in a normalized form. The consolidation deformation characteristics of saturated soft soils are analyzed；and the difference between the proposed theory and Terzaghi¢s consolidation theory is pointed out. In order to express the nonlinear consolidation characteristics，a new parameter called nonlinear parameter l is defined，and the effects of l and thickness of soil layer h are analyzed. The comparisons between calculation results and some typical test results show that the proposed model can be well used to describe the consolidation characteristics of saturated soils. The studies show that there is an obvious difference in the characteristics of consolidation deformation with the changes of thickness of soil layer；and these differences are mainly induced by the nonlinear characteristics of soils instead of simply by secondary deformation effect among the primary consolidation process.

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VISCOELASTIC CONSOLIDATION ANALYSIS OF HOMOGENEOUS GROUND WITH PARTIALLY PENETRATED VERTICAL DRAINS

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2005, 24 (11): -1972 doi:
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Soft soil layer is sometimes too deep to be penetrated by vertical drains in engineering practice. Merchant rheological model is adopted；and the viscoelastic analytical solutions are derived for the consolidation of homogeneous ground with partially penetrated vertical drains based on the existing consolidation theory of ground with partially penetrated vertical drains. Interaction relation between the section with vertical drains and the section without has been taken into account in the solution. In addition，the effects of both well resistance and smear action also have been considered. The solutions have been coded into a program and it is used to analyze a case of homogeneous ground with partially penetrated vertical drains. The results show that viscosity has little effect on the forepart consolidation rate. However，it slows the average consolidation degree in the later period. Soil viscosity has greater effects on the substratum than those on the section with vertical drains.

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EXPERIMENTAL STUDY ON THE MECHANISM OF EARTHQUAKE-INDUCED DIFFERENTIAL SETTLEMENT OF BUILDING ON LIQUESCENT SUBSOIL BY SHAKING TABLE

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2005, 24 (11): -1978 doi:
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The shaking table test of soil-structure interaction(SSI) is introduced. It includes the earthquake- wave-input large table tests and sine-wave-input small table tests. The structure and the subsoil are uniformly distributed；and one direction horizontal seismic waves are input. The dynamic stresses and pore pressures at symmetrical places under the structure and the differential settlement at symmetrical vertexes of the structure are achieved. Results show that：(1) the vertical dynamic stress histories are easily taken with the antisymmetrical distribution in the two sides of the symmetrical foundation；(2) the vertical dynamic pressing stresses in the two sides of the symmetrical foundation are very important for increase of pore-pressure；(3) the asymmetry of the seismic waves bring unbalanced distribution and differential settlement；and (4) when inputting sine-wave，the contrasts of dynamic stresses and pore pressures at symmetrical places under the structure are not obvious；and the uniform settlement will happen.

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STUDY ON THE COUPLED DAMAGE OF TEMPERATURE AND MECHANICS FOR SALT ROCK

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2005, 24 (11): -1986 doi:
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The investigation of coupled damage of and temperature mechanics(TM) for salt rock is very significant for the underground space in the salt rock. Based on previous studies and with the relation of statistical mechanics and fractal rock mechanics，the damage formulation of the coupled damage of temperature and mechanics is deducted. In order to verify the formulation，the experiments of salt rock under different confining pressures and temperatures are carried out. At the same time，the effects of confining pressure and temperature on the mechanics of salt rock are analyzed. Through the experiment，the results show that the confining pressure can restrain the damage increasing，and at a certain range of temperature，the temperature can weaken the damage increasing. The theoretical results agree well with the test results.

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STUDY ON THE RELATION OF GSI AND FRACTURE TOUGHNESS K

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2005, 24 (11): -1992 doi:
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At present，the relation of the macroscopical and microcosmic parameters through the macroscopical parameter or the microcosmic fracture toughness test has seldom been found. The damage will initialize in the rock mass during unload because of the cutting；and it is difficulty to define the relation from the laboratory test and another parameters. However，there is a relation between the macroscopical and microcosmic parameter. A series of equations are proposed for the relation about the geological strength index(GSI) and the fracture toughness K. It is found that the results achieved from the equations agree well with those of in-situ test and laboratory rest.

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THE OBJECT-ORIENTED DEEP-SEARCHING GENETIC ALGORITHM AND ITS APPLICATIONS TO THE ENGINEERING(Ⅰ) —ALGORITHM AND PROGRAMS

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2005, 24 (11): -1996 doi:
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The theory of genetic algorithm is analyzed using the object-oriented method. It shows that it¢s very compatible for the genetic algorithm to be coded with the object-oriented method. On the basis of above analysis，an object-oriented deep-searching genetic algorithm is developed. It¢s a multiple searching algorithm，and it has two strong points：(1) it can be embedded in other object-oriented systems expediently；and (2) it can improve the searching performance of genetic algorithm；and this algorithm can get the best optimum result of the problem farthest. Based on this algorithm，the optimization programs of three kinds of landslide support structures and three kinds of deep foundation pit support structures are developed，respectively. These programs can be used alone for optimizing the corresponding structures and estimating the cost of the structures；and they can be used jointly for selecting the better support structure type as well.