Meso-crack growth caused by the seepage pressure has a great significance for the macroscopic mechanical behaviors in brittle rocks. A meso-macro stress-strain constitutive model considering seepage pressure is proposed. The effects of seepage pressure on initial crack surface and wing crack surface are considered in this model. Seepage pressure weakens the normal stress on initial crack surface，and enhances the crack tension force on wing crack surface，which explains the mechanism of seepage pressure-induced crack growth. A variable of tension force at wing crack surface，i.e.，Fp，caused by seepage pressure is introduced into this proposed model，which has a key function in crack growth to failure of rocks. Combing a suggested relationship between crack growth and strain by relating meso-damage with macro-damage，the stress-strain constitutive relationship caused by microcracks growth under seepage pressure is established. Effects of seepage pressure on the stress-strain curves are studied. Rationality of the proposed model is verified by comparing the experimental data. Variations of the tension force at wing crack surface or the ratio between the tension force at wing crack surface and the tension force at initial crack surface (i.e.，Fp/Fw) with wing crack growth are analyzed. Effects of seepage pressure on crack initiation stress and peak strength are discussed.

The rocks with vein defect structure were taken from the Daguangbao landslide，the surface area of vein was counted based on the technology of image recognition，and uniaxial compression and unloading tests were carried. The acoustic emission characteristics of rocks with vein detect under loading and unloading are studied in this paper. The experimental results show that，the loading and unloading stress in the elastic stage generated acoustic emission，and the accumulate counts of acoustic emission increase with the increase of loading and unloading numbers. The area ratio of vein mass has a great influence on the acoustic emission，the bigger the area ratio of vein mass，the acoustic emission of more frequent and dense will produce. The smaller the area ratio of vein mass，the less the number of acoustic emission will occur. The unloading plays an important role in the formation，propagation and fracture of micro-cracks in rocks. In this paper，the characteristics of rock damage and strength degradation caused by the non-compatible deformation of vein defects and rock during the earthquakes are revealed by acoustic emission.

The simulation test of rockburst in granite roadway is carried out and the three-dimensional space model of rockburst specimen is constructed by CT scanning. The failure mode of tunnel wall after rockburst is analyzed，and the process of rockburst development and its incubation mechanism are discussed based on the geometric shape and distribution characteristics of cracks. The results show that the failure pattern of tunnel wall after rockburst has significant duality in spatial distribution，which include V-shaped and pan-shaped two types of rockburst pits. The V-shaped rockburst pit is narrow and deep，and the pan-shaped rockburst pit is wide and shallow. The spalling phenomenon occurs on the tunnel wall，which produces many cracks approximately parallel to direction of principal stress. The farther away from the tunnel wall，the shorter the crack length，and the tensile fracture is the main failure mechanism. At the same time，many cracks nearly perpendicular to direction of principal stress are formed on the tunnel wall under shear stress，which is distributed within the diameter of the hole. The above cracks parallel and perpendicular to direction of principal stress interleave with each other，and bond to form a trap. After the rocks in the traps are ejected，rockburst pits are gradually formed. The occurrence mechanism of slab buckling rockburst can be summarized as follows：slab cracking failure，shear buckling fracture，rock mass ejection. Slab fracture and shear fracture are two core processes of rockburst，which are related to tension and shear fracture respectively. Among them，the plate cracking caused by tensional fracture provides the material basis of rockburst，and shear crack initiation and propagation provide a catastrophic "inducing factor" for the occurrence of rockburst，which is the key to the occurrence of rockburst. The research results provide strong evidence for revealing the mechanism of rockburst in roadway，which enrich and improve the understanding of the mechanism of slab buckling rockburst.

Excavation and unloading from surrounding rock of underground caverns often cause failure modes such as tension and shear. In order to study the influence of different failure modes on the morphological characteristics of rock fracture surface，the direct tensile test and tension-shear test of black sandstone are carried out，and the two-dimensional and three-dimensional evaluation index are introduced to quantitatively characterize the rock fracture surface. The morphological characteristics of the rock fracture surface under the tensile stress are obtained，and the effects of different rupture mechanisms on the morphological characteristics of the fracture surface are briefly discussed. It is found that all kinds of roughness evaluation indexes decrease linearly with the increase in tensile stress. At the same time，based on the measurement of the anisotropic characteristic parameter ，the three-dimensional roughness evaluation index can accurately characterize the roughness of the rock fracture surface compared with the two-dimensional index ，and it has an exponential relationship to the tensile stress. For the direct tensile test，the difference in the morphology of the rock fracture surface is the smallest；for the tension-shear test，the degree of anisotropy of the fracture surface gradually increases to the decrease of the tensile stress. The results show that different rock failure modes and rupture mechanisms are the root causes of the differences in the morphology of the fracture surface.

The model test(similar ratio：1︰50) has been implemented based on the Yangmingci subway station，and the finite element limit analysis method has been applied. The law of surrounding rock deformation，progressive failure mode and ultimate bearing capacity has been studied. The results show that：(1) The arch cover can effectively restrain the deformation of surrounding rock，especially in the lower excavation stage of tunnel. (2) The deformation of surrounding rock and support can be developed smoothly during the construction sequence by the appropriate timing of arch cover application. (3) The strength of surrounding rock at the arch foot and the side wall and invert are the key to ensure the bearing capacity of the tunnel with arch cover. (4) the results obtained by the finite element limit analysis method are in good agreement with the results of the model test，which can be used as a supplementary analysis of the laboratory test. The research results can provide theoretical guidance for the design and construction of the primary support arch-cover construction method.

For the practical procedure of oil production，stress field affects a much larger area than the reservoir domain，which requires a large amount of computation to simulate using recent approaches for fully coupled fluid flow-mechanics reservoir simulation. In order to increase numerical simulation efficiency，a hybrid method mixing finite element method(FEM) and finite volume method(FVM) is improved to consider the differences of computational domain between fluid flow and mechanics. A fine mesh is used for the computation of seepage in the reservoir domain to catch the detail distribute of fluids，whereas a coarse mesh for stress computation to reduce computational cost. The equilibrium equation of fully coupled approaches is discretized on the coarse grid by finite element method，and the mass balance equation is discretized on the fine grid by finite volume method. Numerical results of both Terzaghi′s and Mendal′s consolidation problems show great consistency with their analytical solutions，which verifies the proposed method. In order to analyze the fluid flow-mechanics coupling effect to reservoir simulation，the numerical results of a two dimensional single-phase flow problem with constant pressure pumping and a three dimensional two-phase flow case in five-spot scheme are carried out.

Combined the moving least squares(MLS) based on the approximation of nodes with numerical manifold method(NMM)，the meshfree-numerical manifold method is developed，abbreviated as MLS-NMM. MLS-NMM owns lower mesh-dependency and higher calculate precision than NMM，and naturally solves the continuous and non-continuous problems in a unified way. To increase the adaptability of MLS-NMM about analyzing the linear elastic fracture problems，a new MLS-NMM is proposed. It makes the mathematical patches containing the same crack tip integrate into a complex patch，in which the finite items of Williams’ displacement series are defined as the local approximation in ordering to reproduce the displacement field of the crack tip. And the method of quadtree′s local refinement is adopted to enhance the calculate precision in the vicinity of the crack tip. This method can directly acquire the stress intensity factors(SIFs) using the relationship between SIFs and items of Williams′ displacement series，avoiding post-processing solution such as the interaction integral method. In this paper，the maximum circumferential stress criterion is applied to decide the direction of crack propagation. At last，two examples of SIF and two examples of crack propagation are simulated，the results reveal that the proposed method can effectively deal with the linear elastic fracture problems，and simultaneously suggest that 2 layer local refinement and 9 items of Williams′ displacement series should be used.

In order to explore the mechanical characteristic of slope under flexible protection，the soil slope model under reinforced three-dimensional mat -anchor protection was designed and made. The earth pressure cells，axial force sensors，dial indicators and other components were set inside and outside the model. Various stages of uniform loads were applied to the top of slope to test the development of stress，deformation and anchor axial force. Finally，the mechanism for flexible protected slope was discussed. The results show that the deformation and bearing capacity of slope under overloading condition have experienced three stages，which is elastic compression，bearing capacity development and yield failure. The lateral displacement mode of the slope surface was firstly “concave in the middle-upper part，convex in the lower part”，and then changed to “integral convexity” with the increase of load. The lateral deformation of the inner slope was mainly distributed near the middle-upper part of the slope surface，and the deformation contour was in circular-arc shape. The vertical deformation of the slope surface mainly occurred in the upper middle part of the slope. The vertical deformation of the inner slope mainly distributed directly below the loading zone. Under overloading on slope top，the upper anchor worked first，and its force was also greater than that of the middle and lower anchors. The strength design of the anchor should be in a progressive way.

Structural plane is the key factor to determine the mechanical properties of rock mass. The shear strength of the structural plane of rock mass is calculated based on the principle of energy conservation and Mohr-Coulomb strength criterion，and its feasibility is verified by the laboratory direct shear test，which is compared with the structural plane strength criterion proposed by previous research. And the testing method of the shear strength of the structural plane is proposed according to the actual rock mass structure. The following concussions can be obtained by the research. (1) The shear strength of the structural plane of the rock mass can be calculated by using the principle of energy conservation and Mohr-Coulomb strength criterion. (2) The morphological characteristics of the structural plane have an important influence on its shear strength，which is mainly manifested as the undulation degree，undulation angle，roughness and the proportion of the raised part. In the two-dimensional condition，the length is taken as the measurement standard，and in the three-dimensional condition，the proportion of the concave and convex region in the area should be considered. (3) The shear strength can be calculated indirectly and simply by measuring the morphological of the structural plane and the strength parameters of the structural plane wall.

Aiming at deficiency of the numerical calculation method of damage zone of surrounding rock in tunneling by drilling and blasting，the elastoplastic damage model based on generalized Hoek-Brown criterion(H-B) is established which considering the cyclic blasting effect. First of all，the rock cumulative damage(RCD) evolution formula under cyclic blasting effect located in far-field is deduced based on fatigue damage theory. The RCD is coupled with the plastic damage caused by stress redistribution and an elastoplastic damage model based on generalized H-B criterion is established. Secondly，the numerical solution of the damage model is given by using completely implicit stress reflection algorithm and operator separation method. Finally，the model is applied to the stability analysis of surrounding rock of Dalian metro project. The RCD evolution formula is verified by field acoustic monitoring. The displacement value and damage area distribution characteristics of the studied section are calculated. The results show that the RCD formula can well express the rock damage evolution law under cyclic blasting. The elastoplastic damage model can reflect the distribution characteristics of surrounding rock damage area under different blasting times，which is more advantageous than the traditional method and has a better guiding effect on engineering safety design.

Based on the research results of saturated porous medium and considering the influence of thermal effect，the propagation characteristics of body waves in saturated porothermoelastic medium are studied in this paper. The thermoelastic wave equations are established by means of thermal coupling momentum balance equation and seepage continuity equation in porothermoelastic medium and the dual-phase-lag model. By introducing potential functions，the dispersivity characteristic equations of body waves in saturated porothermoelastic medium are derived theoretically. The velocity variation of four body waves(P1 wave，P2 wave，S wave and thermal wave) with thermal physical parameters such as frequency，porosity，permeability coefficient，thermal expansion coefficient，thermal conductivity and phase-lag of heat flux and temperature gradient is analyzed with numerical examples. The results show that the increase of thermal expansion coefficient will cause the increase of wave velocity of P1 wave and P2 wave and the decrease of wave velocity of thermal wave. The increase of thermal conductivity and phase-lag of temperature gradient will only cause the increase of wave velocity of thermal wave，while the increase of phase-lag of heat flux only causes the decrease of wave velocity of thermal wave. The variations of frequency，porosity and permeability coefficient have a great influence on the wave velocity of various thermoelastic waves，which cannot be ignored.

The control of excavation deformation and reinforcement of vertical slope rock mass of the three gorges project is the key to ensure the timely impounding. Based on the analysis and demonstration of space relationship of excavation and reinforcement，and overall stability，this study solves the complex construction problems on the stability of lower bedrock blasting excavation and overhanging rock mass of the second ship lock head along north line. Through the application of advanced anchorage，individualized controlled blasting，efficient reinforcement of overhang rock mass，rapid construction of long anchor cables and concrete backfilling，the treatment scheme and engineering procedures of the overhang rock mass on the slope is proposed. The safety，high quality and high-efficiency construction of the ship lock are sure，and the ship lock is put into operation on schedule in 2003. The monitoring results show that the ship lock has been in smooth operation for 16 years. The engineering procedure proved beneficial in contributing to the avoidance of overhanging rock mass failure during construction，and have important reference significance for similar projects.

Based on the curved Euler beam theory，this paper presents an analytical solution for the double lining structure of shield tunnels. Partial-interaction composite curved beam theory is employed to simulate the double lining，and mechanical springs are used to reflect the radial joints effect. The solutions for the internal forces and deformations can be derived by the state space method for arbitrary loadings and variable joint distributions. The solutions revalidated by a comparison with the results of the existing analytical method and numerical model. Using the present solutions，the influence of different joint distributions on internal forces and deformations of the lining are discussed，and the variation trends of internal forces and deformations varying with interlayer shear stiffness between inner and outer linings are also examined under different joint stiffness conditions. The results show that：(1) Increasing the interlaminar shear stiffness can enhance the overall stiffness of the double lining，while the axial force increases，and the bending moment decreases. (2) The bending stiffness of the joint has a significant influence on the bending moment and deformation，but has less influence on the axial force；(3) When the tension and compression stiffness of the joint is too small，the double lining with larger interlayer shear stiffness will be more likely to exhibit a deformation mode different from the‘elliptical’mode because of the greater tendency of the inward contraction. The results obtained from this study may provide useful guidance for design of the double lining structure of shield tunnels.

The distribution of the bedding weak plane directly affects the acoustic and mechanical characteristics of bedding rock mass, and also directly affects the rationality of the value of the rock mass mechanical parameters. Sandstone samples with 7 bedding dip angles，such as 0°，15°，30°，45°，60°，75° and 90°，were prepared for longitudinal wave velocity test and uniaxial compression test. The results show that：(1) With the increase of bedding dip angle，the longitudinal wave velocity and elastic modulus of bedding sandstone gradually increase，and the peak compressive strength shows a U-shaped trend of first decreasing and then increasing，and the anisotropic characteristics are obvious. The elliptic curves of longitudinal wave velocity，elastic modulus and cosine value of bedding dip angle of bedding sandstone are established respectively. Only by testing the longitudinal wave velocity and elastic modulus of bedding rock mass in two directions of parallel bedding and vertical bedding，the longitudinal wave velocity and elastic modulus of rock samples with arbitrary dip angle can be determined，which provides a practical and convenient method for determining the acoustic parameters and elastic parameters of bedding rock mass in different directions；(2) The main direction of stress of the bedding rock mass determines its bearing capacity and deformation and failure characteristics. When determining the relevant basic parameters of engineering rock mass quality evaluation，we should pay attention to the influence of bedding angle, and the testing direction should be consistent with the main stress direction，or the acoustic parameters and mechanical parameters of parallel bedding and vertical bedding should be tested respectively，and then converted to the corresponding bedding dip angle according to the established empirical formula for analysis，so as to obtain more accurate rock mass quality evaluation indexes. Relevant research results can provide a good reference for testing and analyzing anisotropic acoustic and mechanical properties of bedding rock mass.

In order to solve the key technical problems of multiple interference signals，poor adaptability and low prediction accuracy in the seismic wave advance geological prediction during the new tunnels construction，a high-performance 3D directional geological prediction method which suit to the space and process of the tunnel construction is established by using the easily operated hammering source in this paper，and exploratory test research is carried out in combination with several newly-built tunnels on Zhang-Ji-Huai Railway. The results show that：(1) The directional three-dimensional advance prediction method is suitable for tunnel construction space and construction process，which can effectively improve the accuracy of advance geological prediction. (2) The 18-pound hammer source has low excitation frequency and strong energy，which can meet the requirements of the new tunnels. and the prediction distance is over 100 m. (3) Hammering source has strong repeatability，which can improve the signal-to-noise ratio and fidelity by stacking. It is an ideal low frequency source for tunnel advance prediction. (4) This method is easy to operate and control，and can be used in different tunnel excavation methods. (5) This method has high prediction accuracy and clear detection direction，and can accurately predict the bad geological conditions such as karst，water gushing，fault and surrounding rock grade behind the tunnel face.

On the basis of reviewing the existing research status of cumulative damage of rock mass and summarizing the existing engineering application fields of radon，this paper attempts to apply the detection technology of radon to the research field of rock damage mechanics，so as to monitor the evolution process of cumulative damage of rock mass. Based on the above research purpose，a test device for surface radon detection of radioactive rock cumulative damage is designed，and the system is integrated to implement the test scheme. The test results show that radon detection technology can effectively identify the damage trend of loaded rock mass. K-means clustering algorithm is adopted，and the comprehensive damage degree is defined，and it is found that the cumulative damage evolution curve of rock mass blasting has three obvious stages and shows the shape of "inverted S". Based on the measured data of radon exhalation rate on the surface，it is proved that there is a certain linear relationship between radon exhalation rate and cumulative damage in rock mass，and the feasibility of using radon to detect cumulative damage is further verified. The results show that the cumulative damage of the loaded radioactive rock test blocks can be reflected by the surface radon detection technology，and finally the correlation between the cumulative damage characteristics and the continuous change of radon exhalation rate is obtained. The radon exhalation rate prediction index K is used as a new definition of damage degree，and the subsequent multi-angle accurate prediction of dynamic disasters provides a theoretical basis.

In order to solve the problems of the large randomness of index weight calculation leads to low prediction accuracy in rock burst tendency evaluation and the judgment of the rock burst propensity level is too singular，etc. An evaluation method of rock burst propensity based on improved comprehensive weighting is proposed. The 15 factors corresponding to lithological conditions，stress conditions and surrounding rock conditions are comprehensively selected as the judgment index of rock burst tendency，and then applying comprehensive weighting method to obtain comprehensive weight. On this basis，the cloud normal model and ideal point method were used to evaluate the rock burst tendency of specific engineering cases respectively，to judge the level of rock burst tendency，and to verify the accuracy and reliability of the method. The results show that five indicators have a greater impact on rock burst propensity which are the energy storage consumption index k，T criterion，dynamic DT parameters，elastic energy index Wet and stress index S，the index weight result calculated by the improved comprehensive weighting method is more reasonable. Compared with the ideal point method，the evaluation result of the rock burst propensity grade obtained by the cloud normal model is more accurate. The research results will provide new ideas for the prediction of rock burst propensity for geotechnical engineering such as mines，tunnels and hydropower stations.

The propagation of stress waves in discontinuous structural plane such as jointed rock mass and weak interlayer is an important research direction of rock dynamics. The time delay and amplitude attenuation always occur, as the wave across viscoelastic rock. The rock mass was assumed as the Kelvin body in this paper，and the wave propagation equation in the viscoelastic body is established using the wave quality factors. The interaction between the P wave and a linear elastic structural plane is analyzed. Based on the solution of the reflection coefficient of P wave passing through the structural plane in the frequency domain，the propagation rules of the planar stress wave in viscoelastic rock mass，which contains a linear elastic structure surface，was analyzed. Then the expressions of the transmission velocity of P and S waves at any point on the monitor-surface were obtained. The normal and tangential transmission coefficients of plane P wave through the structural plane of viscoelastic rock mass are calculated，using the superposition principle of wave. The parameter studies show that the attenuation and time delay are obvious，when the stress wave propagates in the viscous elastomer. And the structural surface characteristics and incident wave frequency have certain influence on the transmission coefficient.

By means of on-site monitoring and theoretical analysis，this paper reveals the asymmetric deformation mechanism of 1021 roadway which is under the influence of isolated island coal pillar in #10 coal seam in Shanxi Province. And a reasonable roadway support is put forward. The results show that：The abutment pressure of isolated coal pillar will cause stress changes in the floor. The angle between the principal stress and the horizontal direction of 1021 roadway is 19°. The maximum principal stress comes from the direction of isolated coal pillar and the minimum principal stress comes from the direction of goaf above the roadway. The deflection of the principal stress leads to the development of the plastic zone of the roadway surrounding rock in a diagonal pattern，and the roadway presents asymmetric damage. The position of the maximum bending moment of the roadway top beam increases with the asymmetric coefficient λ of the load. And the position will gradually approach the side of the roadway near the isolated coal pillar. The maximum bending moment increases linearly with the increase of λ. The column support should adopt the asymmetric form. The floor heave type of roadway belongs to compound floor heave. The roadway direct floor is flexure fold floor heave. The position of the maximum floor heave is shifted with the change of asymmetric coefficient λ. When λ = 2，it is symmetrical. The basic floor is an extrusion flow floor heave. The displacement velocity of the floor plate increases continuously in the process of being far away from the isolated island coal pillar，the angle between the velocity and the horizontal direction also increases. It leads to the asymmetry of floor heave. Finally，according to the deformation characteristics of 1021 roadway surrounding rock，the paper puts forward the asymmetric support suggestions of roof and floor.

There are few studies on the overall failure mode of the soil-rock dual slope in China. In order to explore the overall stability analysis method of the dual-element slope of soil and fully weathered rock in Jinan，based on the overall failure mode of the same team with the same geological conditions of circular arc sliding，the Swedish circular arc method was applied to the soil layer and the fully weathered rock slope. Analyze and obtain the slope stability analysis solution of the horizontal integration model and the vertical integration model，and use the finite element method to verify the specific calculation example. Finally，select typical soil and weathered rock strata in Jinan area，use plaxis 3D finite element software，analyze the slope and the ratio of soil layer to rock layer on the slip surface slope top crack point and safety factor，and propose the value of slip surface slope top crack point Fit formula. The results show that the safety factor obtained by the horizontal integration model is slightly less than the vertical integration model，and the safety factor obtained by the analytical solution is less than the finite element method. The fixed slope height，the thicker the soil layer of the dual element slope of soil and fully weathered rock，the edge The more unstable the slope；The smaller the slope，the greater the safety factor. The research results can be used for reference in similar projects.

In the model experiment，its authenticity will be affected by the composition and mix ratio of the simulated material. In this paper，first，based on the similarity theory and considering the dead weight of the model，the target value of the simulated material is determined. Then，on the basis of previous studies，materials such as sand，cement，gypsum，diatomite，red clay and marl powder are selected. Finally，the compressive strength and density are taken as the key control to conduct the preliminary experiment and the appropriate group is selected for the follow-up experiment. It is concluded that when the prototype rock mass is in medium or weak weathering state but has high compressive strength，it is advisable to choose the scheme with high proportion of cementing materials and low proportion of sand. When the prototype rock mass is in the state of strong weathering but has low compressive strength，it is advisable to choose the scheme with high proportion of sand，high proportion of regulating material and low proportion of cementing material. Changing the content of diatomite and marl powder in the material has a significant influence on the internal friction angle of the simulated material. Increasing the content of red clay can slightly improve the cohesion of the simulated material. By changing the proportion of each material，the physical characteristics in different weathering states of the same prototype rock mass can be simulated more accurately. The credibility of subsequent model experiments can be improved.

In order to analyze the influence of fracture geometry on the weakening of mechanical properties of rock mass after grouting，different crack inclination angle，crack penetration degree and number of cracks were prefabricated by cutting diabase. A simple grouting mold for fractured rock samples was designed and applied for indoor grouting test. The uniaxial and conventional triaxial compression tests of the diabase and its fracture-grouting mass and the indoor grouting test of the fractured rock samples were carried out. The stress-strain relationship and mechanical properties of diabase fracture-grouting mass under different fracture geometries were analyzed comprehensively. The main conclusions are：(1) Filling the cement slurry in the fracture and confining pressure significantly change the stress-strain relationship of the rock sample，from the typical brittleness of the original rock to the elastic-within a certain range plastic-brittle or ideal elastoplasticity. In addition to the occurrence of slippage along the fracture surface，the ductility of the post-peak zone is significantly improved；(2) The fracture significantly reduces the mechanical properties of the rock sample and the fracture-grouting mass exhibits obvious anisotropy. The mechanical properties are the worst at low confining pressure，full penetration，and 60°crack inclination angle in the most unfavorable state. Providing theoretical reference for selecting line orientation and strength parameters in rock mass tunnel engineering；(3) The rock sample failure under full penetration conditions is dominated by large shear-slip deformation along the fracture surface，and is supplemented by longitudinal-oblique tension-shear cracks；the rock sample failure under semi-through conditions firstly originates from the crack tip cracking，and then the crack tracks the direction of the maximum principal stress，which causes the penetration，or crack tracking shear surface to reach its shear strength and shear failure. It provides guidance for the design and construction of the corresponding fractured rock mass (rock) mechanical engineering，which has certain theoretical value and practical engineering significance.

In order to understand the state of surrounding rock timely and support type，it is necessary to depend on effective monitoring methods and reliable monitoring data in the process of underground engineering construction. Jinping II deep buried tunnel is given priority to brittle marble. The maximum depth is 2 525 m，more than 75% of the buried depth is more than 1 500 m. A large tunnel of 14 m diameter is excavated in such a complex geological environment，will face with the huge project risk. The target and indicative of monitoring method is difference from the shallow condition. The compression test and excavation response showed the main response after excavation of complete marble is not deformation，but fracture. A thorough interpretation was carried on deformation，stress and sound wave test result of Jinping II deep buried tunnel. Research results show that when the surrounding rock is failure，the deformation may still in the range of surrounding rock deformation control standards. The deformation monitoring has lost the significance of early warning，and the anchor stress meter is more sensitive on the state of the surrounding rock than multi–point displacement meter，and has more warning value. The acoustic test results were well consistency with anchor stress monitoring results. Finally，the numerical method was used to describe the internal stress state of surrounding rock in detail，and the brittle–ductile–plastic conversion characteristic of marble can reasonably explain the contradictory relationship between the deformation and fracture.

Creeping landslide causes significant erosion，regulate hill-slope angles and topographic relief，and is one of the main geological disasters that damage infrastructure. Therefore，the stability evaluation of creeping landslide has important scientific significance and application value in the engineering field. Traditional limit equilibrium method and numerical simulation often do not consider the information of initial slip conditions changed by the settlement of the trailing edge slope，thus they cannot explain the stepped deformation of creeping landslide. Based on the creeping landslide experimental case，this study focuses on the mechanism of creeping landslide，establishes a new mechanical model and evaluates its stability. The results show that the settlement of the fault zone changes the initial condition of the slope. The cause of the creeping landslide is that the initial kinetic energy is not zero. Considering the change of the initial conditions，the stability coefficient once dropped below 1.0，which reflected and explained the stepped deformation of creeping landslide. When evaluating the stability of creep-type landslides on the fault zone，it is necessary to consider not only the changing mechanical indexes and boundary conditions such as groundwater，but also the initial condition information changed by the environmental variation such as large settlement of trailing edge slope. The improved stability evaluation method can offer a foundation for better responses to creeping landslide in engineering.

There are high nonlinear characteristics between the micro-mechanical parameters and the macro- mechanical parameters of the discrete element. At present，the manual calibration of the parameter calibration method has great randomness and blindness，the calibration process is inefficient，and the calibration result is reproducible. Therefore，it is urgent to find a new accurate and efficient parameter calibration method. This paper takes 7 typical loess landslides occurred in Heifangtai from 2015 to 2017 as the research object. Firstly，according to the previous mechanical test and related literature，the values of six eigen parameters are determined. And then，the range of values of the remaining six parameters is calibrated by the indoor angle of repose test and the GEMM material database. Through the remaining six parameters sensitivity analysis，the energy density of the JKR model is determined to be 100 J/m2，and the series of orthogonal tests with 6 remaining landslides as variables are designed. Obtaining the parameters of each group and their corresponding simulation forms(horizontal width of the sliding source area，longitudinal width of the sliding source area，wall height of the landslide，overall landslide drop，slip distance，lateral width of the accumulation area). Then use this as a sample to carry out neural network training，and determine the mapping relationship between the simulated shape and the parameters. The optimal simulation parameters of the six landslides is inverted and calibrated by this mapping relationship，and use it as the value range of numerical simulation parameters of loess landslide in this area. Finally，the reliability and accuracy of the parameter range are verified by the forward performance of the 7th landslide，proving this method can avoiding the complexity and randomness of artificial calibration parameters under the same geological conditions.

3D geological modeling is a valid method to quantitatively study 3D spatial structure characteristics and variation laws. However，there are still some limitations in current geological modeling methods，such as excessive man-machine interaction，difficulty in updating and modifying feedback，and long modeling period. In this paper，a 3D parametric modeling method for engineering-scale geological structure based on NURBS is proposed. For engineering scale geological structure objects，this method includes parametric expression of deformation of geological curves and surfaces，mathematical definition of 3D geological parametric modeling，and mixed data structure model of engineering geology. Implementing parameterized importation of geological point data sets(multi-beam water depth points，contours，drilling points，etc.) in 3D visualization environment，parametric fitting of geological structural planes，parametric generation of geological contours. At the same time，a series of operations，such as parametric cutting and combination of surface and surface and volume are carried out. With the change of geological data sources，geological models can be updated dynamically to meet the requirements of modeling accuracy in different stages. Practical engineering application shows that the efficiency of this method is greatly improved compared with the traditional modeling method，which provides a new technical means for large-scale engineering geological object modeling.

The traditional method of randomly selecting non-slide units has the disadvantage of low accuracy when the evaluation of landslide susceptibility is carried out only based on neural network model. Thus，this paper proposes a susceptibility evaluation model that combines information value with neural network. Taking Shangyou County as a case study area. Firstly，ten environmental factors including slope，elevation，aspect，plane curvature，profile curvature，vegetation index(NDVI)，topographic wetness index(TWI)，distance to stream，distance to road and land use were employed to perform regional landslide susceptibility evaluation according landslide catalog and actual survey in the study area. Secondly，the susceptibility zoning of Shangyou County was carried out with the information value model，and the susceptibility zoning map of Shangyou County was obtained. Then，the non-landslide units were selected from the low-prone area in the susceptibility zone obtained from the information value model，and the test and training sets with the historical landslide points in the landslide catalog were divided. All the grids of the study area were then input into the resulting models to predict the landslide probability. Finally，the natural breakpoint method was used to classify the probability often grids，and a zoning map of landslides susceptibility based on the combination of information value and artificial neural network was obtained. The susceptibility results show that：the area under the success rate curve of the independent information model is AUC = 0.736 4，and the number of historical disaster points located in high-susceptibility areas and higher-susceptibility areas accounts for 55.6% of the total number of disasters；In comparison，the combined model based on both information value and neural network achieved a AUC value of 0.787 4，and the number of disasters located in the high-prone areas accounted for 85.8% of the total disasters. The evaluation accuracy of the information value-neural network is 5.1% higher than that of the information value model，and the number of disasters covered by high-prone areas is 30.2% higher than that of information value model. This implies that the information value-neural network model has better evaluation accuracy. It is verified that selecting non-slide points in extremely low-prone areas derived from the information value model is feasible for landslide susceptibility modelling.

The analysis of dominant orientations of discontinuities of rock mass is a fundamental work for the stability evaluation in rock engineering. The traditional clustering methods have the deviations in the clustering process and results，because these methods cannot effectively filter noisy data. To solve this problem，a clustering analysis method based on netting algorithm is proposed for determining the dominant orientations of discontinuities. By coordinate transformation of orientations of discontinuities，the fuzzy similarity matrix R is established by calculating the similarity between each orientation data. Then，the λ-cutting matrix can be constructed by a given confidence level λ. The clustering result was achieved by grouping samples that are connected together by the latitude and longitude lines of same node. The result indicated that the dominant orientations of netting algorithm were consistent with other methods. Based on this proposed method，there is no need to set the initial groups or the initial clustering centers in advance. It reduces the subjectivity of human intervention and makes the clustering process more reliable. The noise data can be effectively filtered，which leads to more accurate clustering results. The analysis of a case study shows that the netting algorithm is effective and reasonable for clustering orientation data of discontinuities. The study can provide the basis for rapidly and accurately obtaining dominant orientations of discontinuities in rock engineering. It is of great significance in rock mass stability evaluation.

During the excavation by steps of super large-section tunnel，the stress of surrounding rock changes correspondingly，and each step of excavation has different impacts on rock mass. Based on the theory of unloading rock mass mechanics，the different unloading zone and the quality deterioration of surrounding rock are constantly changing in tunnel construction. Combined with double side heading construction of a super large-section tunnel in Guanshui Road station of Guiyang Metro Line 2，the effect of unloading on the depth of pressure arch of super large-section tunnel was analyzed by numerical simulation and theoretical analysis. The unloading effect coefficient was introduced to improve the existing method for calculating the process load of tunnel，and the results were compared with those of the calculation method of process load of existing tunnel and the recommended calculation method of highway tunnel. Comparing with the back analysis and calculation results of surrounding rock pressure based on field displacement monitoring data，the calculation results of the improved method were basically consistent with that，and it shows the method had high accuracy.

Construction joints between compacted bentonite blocks in buffer barrier will be closed due to bentonite hydration and swell during the long-term operation of underground HLW repositories. While this self-healing of joints tends to be inhibited，because the swelling of bentonite will be restricted by salts in groundwater. This work studies the effect of permeat salt content on joint healing performance by permeability，thermal conductivity and microstructure tests. The bentonite-sand mixture is compacted into cake-shaped sample with a joint，in which pellet bentonite with a particle rate of 70% was filled. Chemical solutions simulating the groundwater of Beishan area in Gansu is used to conduct permeability tests by rigid-wall permeameter，followed by thermal conductivity and microstructure tests，in comparison with the tests by distilled water. The results show that the hydraulic conductivity of block joint system is the smallest in case that distilled water is used as permeating fluid. With the increase of total dissolved solid，TDS，from zero to 10 g/ L，the hydraulic conductivity increased from 3×10－10 cm/s to 8.5×10－9 cm/s，more than one order of magnitude，indicating an increased inhibition to joint healing by higher salt content. After permeation test，the dry density in the joint area was increased，while the dry density outside the joint was decreased. This certificates that joint is healed by a process that bentonite swells towards the space where low stress conditions exist. Detailed analysis shows that higher TDS corresponds to lower increment in dry density within joint compared with distilled water，indicating again the salt inhibition effect. When permeat TDS is increased，thermal conductivity，in general，tends to be decreased slowly with a larger variation，indicating a reduction in thermal stability.

Crack is one of the main defects which have significant effects on service performance of the shield tunnel lining. In order to reveal the crack evolution mechanism of the shield tunnel lining，a multiscale model is proposed to simulate the crack evolution of the lining segment test under eccentric loading. And contrast analysis is carried out between the results obtained by eccentric loading test and those by the multiscale model. The results show that the segment experiences from non-damage to I-type cracks in which the cracks mainly propagate along the radial direction，and to Y-type crack with loading. Meanwhile，the cracked concrete under eccentric load can be regarded as transverse isotropy material in radial and circular directions. The deterioration of mechanical properties mainly happens in circular direction and is related to the evolution of cracks and the spatial location. According to this characteristic，ABAQUS subroutine USDFLD is used to realize a simplified simulation method by considering mechanical properties in circular as field variables related to the crack depth and its spatial location. The proposed method can simply and accurately consider the influence of cracks according to the comparison of the results obtained by the simplified simulation method and the multiscale model.

The mechanical parameters of the rock and soil, such as limit pressure， pressuremeter modulus obtained by pre-boring pressuremeter test(PBPMT) are affected by many factors，including the equipment types， measured method，soil properties and data processing method. In this article，based on the current national standards，professional standards and handbooks for the domestic pressuremeter test，the different requirements between standard and regulations on the pressuremeter test and data processing methods were analyzed. Furthermore，a series of important issues for the pressuremeter test are studied，including how to obtain a high quality test hole，stability time of loading at each stage during the pressuremeter test，loading series for the comprehensive deformation calibration test on the equipment，the drawing method for pressuremeter curves and the calculation formula of the pressuremeter modulus. The results show that (1) the ratio of the test hole diameter(Dw) to the diameter of the probe(Ds) can be used to evaluate the quality of the measured pressuremeter curve. And (2) the relationship between the ratio of the radius of the test hole and the probe and pressuremeter pressure can be used to analyze the pressuremeter test results uniformly，which are obtained by using different equipment types and sizes of probes. These results can be regarded as evidences for the improvement of the standards and specifications for the pressuremeter tests in the future. Also the results can offer some valuable references for the technicians and researchers who are engaged in pressuremeter tests.

The geological conditions in mountainous areas are complex and changeable，thus accidents of tunnel surrounding rock occur frequently. It is of great significance to accurately predict and evaluate the stability of surrounding rock in the whole course of tunnel. Therefore，by combining the numerical simulation test，the support vector machine(SVM) and GIS technology，this paper proposed a GIS-SVM combined method for visual prediction and evaluation of the surrounding rock stability of the tunnel. Firstly，on basis of the existing research results，seven evaluation indexes of surrounding rock stability including elasticity modulus and Poisson’s ratio were selected，SVM training samples were obtained by using the strength reduction method and the numerical simulation in FLAC3D. Afterwards，the SVM evaluation model was established based on the sample. Finally，based on the GIS platform，the established SVM evaluation model was simulated to the Baishiyi tunnel of Zhongliang mountain in Chongqing. The research area was divided into six grades：very stable，stable，relatively stable，basically stable，under stable and unstable，and then the stability prediction and evaluation map of the tunnel was formed. Furthermore，the effectiveness of the prediction was verified by the comparative analysis of the various bad geological conditions. Research results are expected to provide scientific grounds which can ensure the safety and stability of mountain tunnel at the construction and operation stage.

Rock burst is one of the main hidden safety hazards in deep underground engineering. In order to effectively deal with the fuzzy information in the process of rock burst intensity prediction，a prediction model of rock burst intensity based on unascertained measure-intuitionistic fuzzy set was established. Five indices including uniaxial compressive strength of rock ，the ratio of rock's compressive-tensile strength ，the stress coefficient of rock ，the elastic energy index of rock Wet and integrality coefficient Kv were chosen as the prediction index of rock burst. Firstly，the single index measure function of unascertained measure theory was used to deal with the measured value of rock burst index to obtain the fuzzy membership degree of index based on intuitionistic fuzzy set and construct the evaluation matrix of single index intuitionistic fuzzy. Then，by synthesizing various subjective and objective weighting methods，the intuitionistic fuzzy set weight vector of multi-source weights was constructed，and the score value of samples and the rock burst intensity grade were gained. Finally，the influence of index weight on rock burst prediction results was obtained by analyzing the fuzziness of index weight based on intuitionistic fuzzy sets. The established model was applied to 20 typical rock burst cases at home and abroad，and the predicted results were compared with the actual rock burst cases and the predicted results of three other models. The results show that the prediction results of the prediction model of rock burst intensity based on unascertained measure-intuitionistic fuzzy set are consistent with the actual situation，and the sensitivity of index weight fluctuation is independent of the weight value. The established model improves the fuzzy information representation ability of rock burst prediction and reduces the influence of sample quality on rock burst prediction model.

The moving distance of the dry granular flow and its impact force on concrete structures are important indices to evaluate the disaster risk. The prime factor which plays an influential role in moving distance and impact force of dry granular flow is the topographic conditions. Based on the three topographic conditions(the concave topography，the slope-toe topography，and the tiered topography) of dry granular flow for a village in mountainous terrain，this paper analyzes the influence of topographic conditions on dry granular flow，accumulation distance and impact on structures，from the energy evolution point of view. The results indicate that，for concave topographic conditions，the kinetic energy conversion of the dry granular flow is higher with longer distance，the extent of damages is high and the impact force on the retaining wall at the toe of the slope is smaller. While for the slope-toe topography，the kinetic energy conversion rate of the dry granular flow is lower，the flow distance is shorter，the extent of damages is smaller and the impact force on retaining wall at the toe of the slope is higher. Under the same initialization mechanism of dry granular flow，the peak impact force for the tiered topography decreases faster than the concave topography，with the increase of distance between retaining wall and the toe of the slope. The results of this research can be a potential reference for the assessment of disaster risk mitigation and design of retaining structures for landslides or collapse granular flows.

The pressure exerted on pore walls by growing salt crystals in salt weathering is a major cause of deformation and damage in porous materials. Crystal growth model in a pore during cooling process was provided. The treatment considered the interaction between crystals and pore walls which is based on kinetics of crystallization. Simulations and tests are carried out to analyze the deformation behaviors of a pore induced by salt heave under conditions of different salt contents，water contents and loads during cooling process. The results show that the deformation behaviors are subjected to volume of salt crystals，initial pore diameter and length-width ratio of salt crystals，and the volume of salt crystals is influenced by water and salt contents，and the loads induced an enhancement of length-width ratio of salt crystals. This model provides a new method for revealing the mechanism and calculating the deformation of salt heave in porous materials during cooling process.

The measured maximum principal stress on the left bank of Shuangjiangkou Hydropower Station is 37.82 MPa，NNW direction，which is the highest measured ground stress of the underground powerhouse system of the domestic hydropower station under construction and under construction，belonging to the high to extremely high stress area. The excavation reveals that the rockburst phenomenon of the left bank cavern group is extremely common and prominent，which is mainly manifested in the prominent rockburst phenomenon of the first layer excavation，the continuous development of the whole section，the large development area，“V”type blasting pit is obvious，the shallow surface 0.2-0.5 m thin-layer circular section is stripped，the rockburst phenomenon is prominent at the initial stage of excavation，with a certain lag effect and a long duration，with typical time and space effect. The statistical law shows that the failure type of rockburst is mainly stress rockburst，with structural rockburst locally developed；the rockburst level of the first layer is slight to medium；the time of rockburst support is suitable for 2 to 3 days. According to the law of rockburst development in the first layer，the preliminary study on rockburst prediction is carried out，such as rockburst failure type，rockburst grade，rockburst time-space characteristics，rockburst failure phenomenon，etc.，in order to summarize the experience of rockburst prediction through the comparison of underground excavation，and provide some reference for other engineering rockburst prediction.

Based on the freeze-thaw cycles tests，the dynamic triaxial tests are carried out to study the dynamic nonlinear parameters of Qinghai－Tibet silty clay. In the test，the effects of freeze-thaw cycles，dynamic loading frequency and moisture content are considered. Then，the backbone curve of dynamic shear stress vs. dynamic shear strain(τd-γd) and the relationship curve of dynamic shear modulus ratio vs. dynamic shear strain(Gd/Gdmax-γd) are obtained. The results indicate that the dynamic behavior of the remolded Qinghai－Tibet silty clay can be described by Hardin-Drnevich hyperbolic model. Freeze-thaw cycles，frequency and moisture content all have significant influence on the dynamic nonlinear parameters of Qinghai－Tibet silty clay，which tend to be stable after 6 freeze-thaw cycles. With the phase transition of pore water during freeze-thaw cycles，the soil structure was deteriorated. It is the inherent mechanism for the drastic changes of dynamic behaviors of Qinghai－Tibet silty clay. When γd is constant(e.g.，γd = 0.001)，τd decreases rapidly first，then increases slightly，and Gd/Gdmax does not change much as the number of freeze-thaw cycles increases，for the sample with moisture content of 18% that has subjected of 1，3，6 and 10 freeze-thaw cycles，τd decreases by 35.4%，48.6%，41.6% and 43.0%，Gd/Gdmax decreases by 6.1%，0.5%，–1.2% and 0.4% respectively. With increasing frequency，τd increases and Gd/Gdmax decreases continuously，as frequency increases from 0.5 Hz to 5 Hz，for the sample with moisture content of 18% that has subjected of 0，1，3 and 6 freeze-thaw cycles，τd increases by 14.4%，22.1%，68.8% and 52.6%，Gd/Gdmax decreases by 4.9%，17.2%，32.8% and 22.6% respectively. Both of τd and Gd/Gdmax decrease continuously as the moisture content increases，as moisture content increases from 13% to 19.5%，for the sample that has subjected of 0，1，3，6 and 10 freeze-thaw cycles，τd decreases by 53.7%，70.6%，77.8%，78.6% and 78.5%，Gd/Gdmax decreases by 18.5%，27.7%，28.8%，24.6% and 30.0% respectively. The research results can provide the dynamic parameters of thawed soil for the seismic response analysis in cold region sites.

To investigate the effect of freezing-thawing cycles on the liquefaction characteristics of saturated loess，a series of freezing-thawing cycles and dynamic triaxial tests were conducted. The characteristics of dynamic residual strain and the dynamic pore water pressure of the saturated loess before and after freezing-thawing cycles were determined. The influence of the freezing-thawing cycles on the cyclic shear cycles on liquefaction failure was analyzed. The characteristics of mean effective stress versus the deviatoric stress and the hysteretic curve of dynamic stress-dynamic strain before and after freezing-thawing cycles were discussed. Moreover，the characteristics of structure and its influence on loess liquefaction were analyzed based on the particle analysis tests and SEM results before and after freezing-thawing cycles. The results show that the freezing-thawing cycles leads to the decline of the anti-liquefaction performance of the saturated loess. The cyclic shear cycles on liquefaction failure decrease significantly when freezing-thawing cycles is less than 5. The dynamic residual strain increases with the increase of freezing-thawing cycles. The dynamic pore water pressure of the soil under freezing-thawing conditions is significantly higher than that of the loess without freezing-thawing cycles，however，the regularity of the relationship between the exceed pore water pressure and the freezing- thawing cycles is not obvious. With the freezing-thawing cycles increases，the clay content of the loess increases whereas the sand content decreases. The clusters of the soil are significantly decreasing. The soil particles tend to break，and the overhead pores are damaged. The change of soil particles and structure caused by freezing-thawing cycles is the main reason for the changes of the characteristics of soil liquefaction.

Aiming at the problem of high energy consumption during electro-osmosis process and the uneven consolidation effect of dredged slurry by electro-osmosis method，the inorganic flocculant CaCl2 was used to optimize the traditional electro-osmosis method，and the dredged slurry was treated by the energization method of step-by-step voltage loading during electro-osmosis process. Meanwhile，the effect of flocculation-step-by-step loading voltage electro-osmosis method in the treatment of dredged slurry under different loading voltage levels and inorganic flocculant CaCl2 mixing ratio was studied. The thirteen laboratory tests were performed on dredged slurry. The test results show that，compared with the traditional electro-osmosis method，the flocculation- step-by-step loading voltage electro-osmosis method effectively reduces the non-electroosmotic energy consumption in the treatment of dredged slurry. Most of the electrical energy is used for the electroosmotic drainage，thereby increasing the drainage of soil. Meanwhile，the flocculation-step-by-step loading voltage electro-osmosis method effectively restrains the attenuation of circuit current，and improves the electro-osmotic drainage efficiency in the treatment of dredged slurry. Moreover，compared with the traditional electro-osmosis method，the flocculation-step-by-step loading voltage method has less anodic corrosion and better integrity of soil. In addition，in the treatment of dredged slurry by flocculation-step-by-step loading voltage electro-osmosis method，when the mixing ratio of inorganic flocculant CaCl2 is 1%，the more the loading voltage level，the better the reinforcement effect of dredged slurry.

Frozen soil as a subgrade for roads and railways，which stability has been widely concerned and studied. In order to seek the failure mechanism of frozen soil under traffic load，the cryogenic temperature dynamic triaxial tests is implemented under the hierarchical cyclic dynamic loading. The dynamic parameters of frozen silt soil are analyzed in detail considering different freezing temperatures，water contents，compaction degree and confining pressure. The results show that there is a good linear relationship between the reciprocal of dynamic shear modulus-strain，hyperbolic model can well express the dynamic stress-strain relationship of frozen silt. The freezing temperature and water content change have significant influence on the dynamic shear modulus and damping ratio，there are optimal freezing temperature and water content range to control their corresponding maximum or minimum values. The compaction degree and confining pressure have weak influence on dynamic shear modulus and damping ratio，the optimal range is not found.

In order to study the effect of isolation pile on controlling the displacement and deformation of the tunnel with adjacent excavation，laboratory 1 g model tests were carried out in dry sand. Three groups of experiments including no isolation pile，isolation pile with embedment depth and isolation pile without embedment depth were designed and conducted. The horizontal displacement of retaining structure and the displacement and circumferential bending moment of tunnel were monitored and studied. The results showed that， without isolation pile，the horizontal displacement of retaining structure，the horizontal and vertical displacements and circumferential bending moment of tunnel all increased with excavation process(an increase of the ratio of excavation depth to the tunnel depth). In the case of isolation pile with embedment depth，compared to the case without isolation pile，the horizontal displacement of retaining structure，the horizontal and vertical displacements of tunnel，and the positive and negative circumferential bending moments of tunnel were all well controlled. In the case of isolation pile without embedment depth，compared to the case without isolation pile，the horizontal displacement of retaining structure，and the positive and negative circumferential bending moments of tunnel decreased. However，the horizontal and vertical displacements of tunnel increased by 32.0% and 123.8%，respectively. It was found that，the tunnel was mainly influenced by the isolation and drag effects of the isolation pile.

Initial stress state has a great influence on the dynamic liquefaction characteristics of saturated sand. Control deviation of stress will lead to large dispersion of liquefaction test results. The influence of control deviation of initial axial stress on liquefaction characteristics of sand is studied experimentally based on the newly developed high-precision DSZ–II static-dynamic unified triaxial test system，supplemented by fine test technology. The control deviation of initial axial stress can lead to the obvious change of liquefaction vibration times in the dynamic liquefaction test under the equal consolidation conditions，which will bring greater uncertainty to the analysis of anti-liquefaction strength of sandy soil. The sand is more likely to liquefy due to stretching under cyclic vibration in the dynamic triaxial test，when the initial axial stress is less than the initial axial stress in the equal consolidation conditions；On the contrary，when the former is larger than the latter，the liquefaction of sand will be more difficult when the deviation is small，but with the increase of deviation stress，the liquefaction will be easier. This conclusion is limited to the case where there is a control deviation of initial axial stress in the equal consolidation，and does not involve the case of large consolidation stress ratio. The dynamic strain can develop rapidly and greatly on both sides of tension and compression under ideal homogeneous conditions，however，the control deviation of initial axial stress will restrict the dynamic deformation amplitude of sandy soil. The deviation has a great influence on the middle development stage of the mean effective stress-deviatoric stress(p'-q) relationship curve，but the p'-q curves of all tests are constrained within the same stress space. This study has reference significance for the accurate determination of anti-liquefaction strength index of sandy soil.

The relationship，dynamic elastic modulus and dynamic strength was studied under different confining pressure and Phosphorus tailings by GDS dynamic triaxial test. The experimental results show that the dynamic strain-dynamic stress( )curves of the improved soil rise first and then decrease with the increase of phosphorus tailings，and the optimal dosage is 7%. The dynamic elastic modulus Ed decreases with the increase of the dynamic strain ，When ≤0.2%，the dynamic elastic modulus decreases rapidly. When ＞0.2%，the soil enters the plastic development stage，and Ed decreases and becomes slow. The dynamic strength curve conforms to the power function relationship；Dynamic strength increases with the increase of confining pressure，and increases first and then decreases with the increase of phosphorus tailings content. Compared with pure expansive soil，the modified soil dynamic strength increases by about 40 kPa，and the increase is about 30%. The improved soil dynamic cohesion cd increases first and then decreases with the increase of phosphorus tailings content；Compared with pure expansive soil，cd increases by about 9 kPa，and the increase is about 36%. The amount of phosphorus tailings has little effect on the internal friction angle φd. The dynamic strength calculation formula is given by nonlinearly fitting the relationship between dynamic strength parameters and phosphorus tailings.

Based on the pseudo-dynamic method and the horizontal layer analysis method，the rigid retaining wall under seismic load is taken as the research object. According to the conclusions of previous experimental research，the calculation expression of seismicnon-limitactive earth pressure and resultant force point in RB mode is derived，which considers the influence of the retaining wall displacement on the exerting value of friction angles. The calculation model is divided into two kinds of non-limit state conditions according to the difference of the maximum displacement of the wall top，and the relationship between the displacement of the retaining wall，the seismic load，and the earth pressure is established. The parametric analysis discusses the influence of the displacement of a wall top on the distribution of the seismic lateral earth pressure，the exertion degree of the friction angle and the resultant force point of the earth pressure. The results indicate that the horizontal or vertical seismic action and the non-limit displacement state of a retaining wall can both increase the resultant force point of active earth pressure. Compared with the traditional limit state seismic earth pressure theory，the proposed method describes the development process of seismic earth pressure with retaining wall displacement more reasonably and has a certain reference for developing non-limit earth pressure theory and improving seismic calculation method in practical engineering.

In order to investigate the effect of hydro-chemical conditions on the self-weight settlement of dredged fill，the cylinder settlement test was carried out in this study，and the settlement and settlement rate were analyzed. In addition，the change in the ion content of the supernatant was determined by titration tests after the sedimentation，and the effect of hydro-chemical conditions on the self-consolidation of dredged fill and the respectively micro-mechanism were investigated. The results show that both alkaline(pH = 10) and acidic(pH = 2) conditions could effectively improve the settlement rate of the dredged fill at initial stage，while the final settlement gradually decreased with the increase of pH value. With the increase of Ca2+ content，the settlement and the settlement rate of dredged fill increased under acidic and neutral conditions，and the settlement and settlement rate of dredged fill showed a trend of increasing first，then decreasing and finally being stable under alkaline condition. The results in this study are meaningful for improving the settlement of dredged fill.

Based on the equivalent elliptical cylinder model，by introducing the e-lgσ' and e-lgkh nonlinear relationships and the linear loss law of the negative pressure in the prefabricated vertical drain(PVD)，a numerical solution and a simplified analytical solution are obtained by the differential algorithm and the simplified method，respectively. On basis of the presented solutions，the comparative analyses between the numerical solution and the simplified solution，and between the degree of consolidation based on pore water pressure(Up) and that in terms of deformation(Us) are conducted. Then，the influences of the ratio of compression index to permeability index，c(Cc/Ck)and the vacuum load on consolidation behavior are investigated. Lastly，the prediction ability of the presented solutions is verified by comparing them with the test results. The results show that，the numerical solution is almost identical with the simplified solution for c = 1，but there is a difference between that two solutions for c＜1 or c＞1. Under different c，Us is always lager than Up at same time，and the consolidation slows down as the increasing of c. As for the consolidation process defined by the dissipation of excess pore water pressure，when c＜1，the consolidation speeds up with the increase in vacuum load; however，when c = 1，the variation in the vacuum load has no effect on the rate of consolidation，and when c＞1，the larger the vacuum load，the slower the consolidation.

In order to investigate the stress state effect on water retention and deformation characteristics of expansive soil. Considering the overburden pressure，a soil-water characteristics curve(SWCC) model of expansive soil is carried out. Furthermore，the equation-fitting process of the proposed model under the different one-dimensional overburden pressure is analyzed. Results show that：(1) The moisture content in Nanyang expansive soil displays a regular change and bimodal characteristics wile matrix suction changes. With the increase of overburden pressure，the water-holding capacity of expansive soil decreases. The boundary effect II is significantly prolonged at 200 kPa overburden pressure. (2) The pore ratio of the soil decreases with the increase of overburden pressure and matric suction. The contribution of pore shrinkage caused by overburden pressure is 2.12 times as much as that caused by matric suction. Under the stress，the loss of void water caused by overburden pressure dominates volume shrinkage in the dehumidification process of expansive soil. (3) Based on the segmentation，the Fredlund-Xing equation is improved by using the proposed bimodal SWCC model to fit the data of Nanyang expansive soil. Fitting parameters a1 and n1 can effectively reflect the characteristic variation of SWCC1 under different overburden pressure. The influence of overburden pressure is weakened in the stage of SWCC2. The relationship between each parameter and overburden pressure is not obvious. The research gives references for the quantitative characterization of the hydraulic-mechanical coupling effect of expansive soil，as well as the study of bimodal characteristics SWCC models.

In the exposition site of Wuhan Garden Expo，a 15 m-high soil mass was designed on a 12 m-thick refuse soil layer of Jinkou landfill. Large overburden load was bound to cause the settlement of whole refuse soil layer. In depth direction，the nature of the refuse soil varied greatly. Therefore，the result of small-scale load test cannot truly reflect the deformation characteristics of the whole refuse soil layer. In this paper，large-scale plate loading testes(6 m×6 m) were carried out. And the engineering performance of the refuse soil layers within the range of the main peak was studied. The development of the settlement under the plate，surface settlement，stratified settlement and horizontal displacement around the plate were monitored and analyzed during loading. Based on these statistics，the overall deformation characteristics and load-bearing failure mode of the refuse soil layer were obtained. The test results showed that the P-S curve of the refuse soil layer under overburden load contained three stages including elastic，elastic-plastic and failure stage. The deformation modulus was 5.66–6.77 MPa，and the ultimate bearing capacity was about 300 kPa. The influence range of settlement deformation run through the whole layer. The final failure mode was punching failure mode.

The dredger fill consolidation under airbag pressurization combined with surcharge preloading (APCWSP) is studied by model test. The lateral pressure of airbag could increase the soil consolidation degree apparently. The consolidation degree is 82.75% and 75.31% for the APCWSP test and surcharge test，respectively，for the same consolidation time of 180 hours. And the engineering properties of soil in APCWSP test are accordingly better. The additional stress caused by pressurization is evenly distributed along the vertical direction. Also，the increment of the soil and pore water pressure decreases as the soil consolidation degree increases. According to soil displacement analysis，the displacement caused by lateral pressure is limited. Foundation deformation is still dominated by settlement. Moreover，the deformation is uneven because of the different drainage distance and device deformation. The result of the model test provides a basis for the application of APCWSP method in practice.

The mechanical properties of stored tailings are the key factors that affect the stability of the tailings dam. Based on the method of chemically improving soil mechanical properties，the mechanical properties of the polymer improved tailings were studied. Results show that the shear strength of tailings improved by polyvinyl alcohol and sodium carboxymethyl cellulose is smaller than that of unimproved tailings. But the shear strength of the tailings improved by polyacrylamide and calcium lignin sulfonate are increased. Compared with the shear strength parameters of unimproved tailings，the cohesion of the tailings improved by polyacrylamide，sodium carboxymethyl cellulose，calcium lignin sulfonate are increased. The cohesion of the polyvinyl alcohol improved tailings is decreased. The internal friction angle of the polyacrylamide and calcium lignin sulfonate improved tailings are increased. The internal friction angle of the tailings improved by sodium carboxymethyl cellulose and polyvinyl alcohol is decreased. Among the four kinds of polymer materials，the improvement effect of polyacrylamide is most significant. After curing for 7 days，the mechanical properties of polyacrylamide-improved tailings tended to be stable. The shear strength of improved tailings increases with the increase of polyacrylamide concentration. Additionally，the results of immersion test，dry-wet cycle test and freeze-thaw cycle test show that polyacrylamide-improved tailings have good water stability and aging resistance.

In view of the problems of the poor filling effect and high cost of cemented cementing material used for fine unclassified tailings cement filling. The low-cost mine filling cementitious materials is developed by using ground granulated blast furnace slag powder(GGBFSP). In order to effectively stimulate the activity of GGBFSP，on the basis of a large number of exploratory tests in the early stage，the multi-objective optimization method of (RSM-DF) was used to carry out the compounding agent optimization experimen. Firstly，the physicochemical properties of the test materials were analyzed. Secondly，based on the influencing factors and the corresponding level determined by the previous experiment，13 groups of experiments were designed and carried out by using Box-Behnken Response Surface Methodology in Design-Expert software. And according to the results，response surface regression model is established to study the influence of three factors and their interaction on 28 d strength，slurry slump and bleeding rate. Then on this basis，the multi-objective optimization method of satisfaction was used to optimize the ratio of composite activator. The results show that the three responses of 28 d strength，slump and bleeding rate are not only affected by a single factor，but also by the interaction between factors. The optimized proportion of composite cementitious material is：clinker content is 4%，desulfurization ash content is 19%，mirabilite content is 0.5%，the GGBFSP is 76.5%. And the verification test was carried out at this ratio，and the 28 d strength，slurry slump，and bleeding rate is 3.42 MPa，18.6 cm，and 6.1%，respectively，which meet the requirements of high-concentration gravity flow transportation. Finally，the hydration mechanism of new filling cementitious material was studied by XRD and SEM，which provided theoretical basis for the utilization of new cementitious material in mines.

The solidified soil was prepared from marine dredged sludge deposited in Dalian bay by adding a proper amount of JCW sludge stabilizer. The microstructure and structural characteristics of solidified soil were investigated by particle size analysis，X-ray diffraction(XRD) and scanning electron microscope(SEM). The internal mechanism is discussed，which changes in macro indicators of solidified soil，such as liquid-plastic limit and unconfined compressive strength. The results show that，during the curing period of solidified soil，the silt with grain-size less than 100 μm shows obvious agglomeration phenomenon，when grain-size are 11 μm and 45 μm. With the increase of curing age，the liquid-plastic limit increases exponentially，while the plasticity index decreases exponentially. The category of soil changes from viscous soil to silty soil，and the state of soil gradually changes from fluid-plastic state to hard plastic and semi-solid state. The three-dimensional network structure formed by the interaction of stabilizer and silt，which promotes the gradual transformation from three-phase system composed of solid-liquid-gas to quasi two-phase system composed of solid-crystal-gas. Unconfined compressive strength of solidified soil increases exponentially with the increase of curing age，unconfined compressive strength increases from 297 kPa to 783 kPa，when curing age increases from 7 d to 180 d.

In order to study the strength characteristics and long-term stability of heavy metal contaminated soil，a series of strength and scanning electron microscope experiments were carried out based on solidified Cu-contaminated soil with magnesium phosphate cement. The freeze-thaw cycle times，magnesium phosphate cement content and copper ion concentration were considered as experiment effect factors，and the strength and microstructure of Cu-contaminated soil solidified were studied under freeze-thaw conditions. The results show that the unconfined compressive strength of solidified soil decreases gradually with the increase of freeze-thaw cycle times and copper ion concentration or the decrease of magnesium phosphate cement content. Under 3 and 12 freeze-thaw cycles，the reduction rate of unconfined compressive strength of solidified contaminated soil is the smallest，and the reduction rate of unconfined compressive strength reaches the peak value when the number of freeze-thaw cycles is 6 to 9 times. The freeze-thaw stability of Cu-contaminated soil of low concentration heavy metal that cured by magnesium phosphate cement is remarkable，and the freeze-thaw stability of solidified soil decreases with the increase of metal ion concentration. The micropore structure of solidified contaminated soil was obtained based on the scanning electron microscope experiment. The content of magnesium phosphate cement increased from 5% to 20%，and the percentage of microscopic statistical pores decreased by 17.43% when the concentration of copper ion was 0.5% and freeze-thawed for 6 times，so the mechanism of strength change is verified. The research provided theoretical and engineering application reference for frozen-thawed areas of northern China to evaluate the long-term stability of solidification treatment of heavy metal contaminated sites.

Based on the literature numerical modeling type II(2D)，a three-dimensional dynamic compaction model considering different load widths is proposed and verified. At the same time，a calculation formula of compaction stress retaining wall considering Chinese norms was introduced，and the three-dimensional dynamic load moving mode was discussed. First，through the selection of equivalent load loading method，the influence of different load widths on the retaining wall is discussed according to the strain of the reinforcement，the lateral deformation of the panel，the soil pressure behind the wall and the compressive stress distribution of the base. And the depth of compaction stress is used to provide verification for the calculation formula. The analysis shows that the calculation method of the equivalent load movement method is closer to the measured value than the second and third methods；the strain change trend of each layer is basically the same，showing two peaks，the first one is located at the back of the panel，the second place Peak load point due to shear strain concentration(potential fracture surface)；the type of compaction modeling does not affect the distribution of vertical compressive stress at the bottom of the wall；only when the additional load of the retaining wall exceeds the compaction load，the compaction stress the effect will dissipate. At the same time，for different compaction stresses，ribs and soil properties，the corresponding compaction depth is also different；The strip load width(B) has obvious impaction on the internal stress prediction of the retaining wall.

The response of Xi?an ground fissure site and its site seismic design were studied by conducting a shaking table model test. According to the test results，the closer of the ground fissure，the greater of the peak acceleration，with the increased of ground fissure distance，the peak ground acceleration gradually decreased and stabilized gradually，and the range of influence was about 30 m in the hanging wall，while 18m in the footwall；with the increased of input ground motion intensity，the peak ground acceleration gradually decreased but at a different rate；the dynamic response of the ground fissure site shows obvious “hanging effect” and “zoning” laws affected by ground fissures，which can be divided into “Yield belts”，“defensive belts” and “safety belts”type；with the increased of input ground motion intensity，the site seismic amplification decreased integrally，which is tend to stabilized when the peak acceleration reached 0.3 g. The model test results provide a theoretical basis for the seismic fortification of the ground fissure site engineering in Xi′an.

The shape of soil arch has not been generally recognized in the piled embankment，hence，further investigation on the soil arching effect has significant scientific research value for the analysis of load transfer mechanism in the piled embankment. The visualized model test device，materials used in the model test and the layout of the measured instruments to analyze the soil arching effect in piled embankment were firstly introduced. The distribution of the settlement and the vertical stress in the piled embankment were then investigated by carried out ten model tests based on this visualized device，in which the height of embankment and the pile spacing were varied. The experimental results showed that that the embankment height h and the clear pile spacing (s?a) are the key parameters for the generation of soil arching effect. For the plane strain condition，when h/(s?a)≤1.0，it can be concluded that the soil arching effect is not generated since the re-established vertical stress in the embankment was not occurred；for the ratio of h/(s?a) is in the range of 1.0–1.5，partial soil arching is formed；whereas when h/(s?a)≥1.6，the soil arching effect fully developed and the inflections of the vertical stress along the height of the embankment were founded，which is similar to the distribution of the vertical stress of embankment derived from the Hewlett & Randolph method. The experimental results also showed that the differential settlement at the surface of the embankment gradually decreased with increasing the embankment height，and approaching to zero for the value of h/(s?a) larger than 1.6. Finally，the equation of the inner and the outer height of soil arching were derived based on the experimental results，which were used to modify the analytical method proposed by Hewlett & Randolph. It can be found that the modified analytical method agreed well with the experimental results.

For the purpose of researching the damage evolution law of granite residual soil under drying-wetting cycles，the uniaxial compression-resistivity testing system were used to test the resistivity-stress-strain curves of undisturbed samples under different drying-wetting cycles. Based on the resistivity testing data，the mechanical damage evolution model of granite residual soil during the uniaxial compression test was proposed. The test results show that the deformation process of the granite residual soil are divided into 3 different stages，corresponding to elastic，plastic and residual deformation stage. A positive linear correlation between values of initial resistivity and peak strengths is found during the process of 0–5 drying-wetting cycles. The damage evolution model based on resistivity can accurately describe the mechanical behavior of undisturbed soil samples under uniaxial loads. Through the application of the initial damage factor，the mechanical model can effectively predict the stress-strain curves of granite residual soil under drying-wetting cycles. The results provide a reference for the application of resistivity testing techniques in rock and soil mechanics.

This article is based on a deep foundation pit project in Lanzhou area which has complex surrounding environment and limited construction space. In the special situation that the foundation piles of the main building have been constructed and the underground garage will excavate subsequently，the article puts forward the idea that regarding the multi-row foundation piles as the support objects for the foundation pit of the underground garage. It also establishes the relevant calculation model to calculate the internal force and deformation degree of the foundation pit during excavation. At the same time，the article verifies the reliability of the model by the finite element tool，and compares the result with the actual monitoring data. The results indicate that：the new support form，“dual-purpose pile”can save space greatly，using group-pile as multi-row pile support，it can control soil displacement and the deformation of envelop enclosure effectively. Compared with the traditional pile-anchor supporting structure，the new one is more economical. It can avoid many constructions of support pile，save much time and material costs，and achieve the“dual-use pile”successfully. This article reflects the huge advantages of the new support structure. It can provide reference to similar deep foundation pit support structure in this area.

Many cross-river subways are often constructed in deep soft soil layers，and the frequent changes of the warp soil above and the water level is a disadvantage to the control of the post-construction settlement. Therefore，the safety of cross-river subway is a challenge to control the post-construction settlement. Therefore，the safety of cross-river subway is undermined when it starts running. In this paper，the bidirectional dynamic triaxial test was operated by trial and error to stimulate the loading of cross-river subway on soft clay sample. The changing curve of pore pressure through dynamic test could be plotted，and a pore pressure model of soft clay under cross-river subway loading can be built. The study shows that：Under cross-river subway loading，the growing of pore pressure is firstly rapid，then slows down and stable. Increasing the effective confining pressure during cyclic loading make the pore water pressure rise，the stability value of pore water pressure will increase with the increase of radial cyclic stress ratio. The quadratic logarithmic model can be used to simulate the pore pressure development of soft clay under cyclic loading. The model takes the effects of radial cyclic stress ratio and effective confining pressure into consideration，which can provide as a reference for post-construction settlement prediction of cross-river subway.

Basin-shaped freezing technology is a water-proofing technology applied to underground excavation subway station in sandy gravel stratum，with the basin wall and basin bottom acting together to form a closed sealing space，the basin bottom uses comb freezing method to form a horizontal frozen plate. In this paper，based on the physical model test，numerical simulation is used to analyze freezing rules and the temperature field development of comb freezing method under seepage condition. The numerical model can effectively reflect the freezing shaping evolution of comb freezing，and the simulation results are in good agreement with the physical model test. Research finds that：(1) In the process of comb freezing under seepage condition，firstly，the frozen area develops along the flow direction，then the last row of freezing pipes on the back-water surface intersect in the direction of vertical flow and finally，the frozen area develops from the back-water surface to front-water surface and forms a closed horizontal frozen plate. Meanwhile，the effective thickness of the horizontal frozen plate is lost to some extent due to the flow around front-water surface. (2) The temperature field in the main frozen area shows a droplet shape along the direction of the flow，and the low temperature part is basically symmetrical distribution centered on the third row of freezing pipes，the temperature field in the vertical flow direction is symmetrical distribution centered on the middle row freezing pipes，and the temperature gradually increases from the core low temperature area to the surrounding areas，and the temperature at the middle of the freezing tube is lower than that at the end.

Considering the traditional GM(1，1) model in slope deformation prediction can not reflect the impact of external environmental changes on the trend of system change and inherent structural shortcomings in GM(1，N) model，OGM(1，N) model was introduced and its background value is optimized by adaptive particle mutation swarm optimization according to the error of background value in gray system. Three monitoring points(G7，G8，G9) on the waste dump were analyzed by grey relational analysis theory. Then the improved OGM(1，N)model was used to predict the waste dump deformation in Jiepailin mine. Compared the results with GM(1，1) model，Verhulst model and Nonlinear regression，the results of three monitoring points showed that the improved OGM(1，N) model is more precise than the other three models. In detail，the average relative percentage error of improved OGM(1，N) model is 0.16%，2.26%，10.562%，respectively. The average relative percentage error of GM(1，1) model is 16.57%，18.07%，19.095%，respectively；the average relative percentage error of Verhulst model is 4.52%，2.34%，29.809%，respectively，the average relative percentage error of nonlinear model is 11.44%，8.45%，11.621%，respectively. Comparing the result of the OGM(1，N) model before and after optimization，the average relative simulation percentage error after optimization was reduced to about more than 1/3 of that before optimization. According to the prediction results of three monitoring points，the improved OGM(1，N) model is adaptive and effective in slope deformation prediction.

To analyze the wellbore stability during drilling in methane hydrate-bearing sediments (MHBS)，an analytical wellbore stability model is established by combining the viscoelastic solution with yield criterion. In this model，the unsteady seepage and temperature fields，as well as the rheological properties of the reservoir are taken into account. The analytical solutions of seepage pressure and temperature which are the functions of space and time are obtained by using the method of separation of variables. The phase equilibrium curve of hydrate is applied to determining the dissociation front of hydrate，and the effect of dissociation on viscoelastic parameters is considered. The solutions of time-dependent stress and displacement considering the influence of seepage are analytically derived by Laplace transform technique. The characteristics of seepage and temperature fields are investigated，and the influence of reduction of mechanical parameters of formations on wellbore stability are also studied. The results show that the influence range of seepage and temperature fields increase with time，and the propagation velocity of seepage field is faster than temperature field. When the ratio of shear relaxation modulus between the dissociated and the undissociated region is a constant，the stress of the formation changes monotonously with time. When the reduction of of the dissociated region is small，the equivalent stress at the borehole wall will reach the extreme value before the steady state，and the borehole wall is in high risk of instability.