The ideas and methodology for the in situ monitoring of rockburst preparation of deep tunnels was described firstly. The time and space evolution law of immediate rockburst observed，which occurred usually during or after excavation immediately and affected mainly by excavation unloading effectiveness，was analyzed. Based on a series of in situ monitoring of deep tunnels，process of crack initiation，propagation，opening and closing，evolution of wave velocity，deformation，acoustic emission and microseismicity were observed. Based on moment tensor analysis of the monitored microseismicity during the excavation of deep tunnels，the difference of mechanism of strain rockburst and strain-structure slip rockburst was found. The former was mainly from tensile cracking but the latter mainly from tensile cracking，shear cracking，and tensile-shear/compressive shear cracking which was from shearing of stiff structures and formed boundary of rockburst pit. The results are used as a guide of prediction of rockburst and its dynamic control based on evolution of the monitored microseismicity and other information. 

Because of the complicated geological condition and especial water condition，the simplex grouting scheme and material can not arrive at the perfect effect，and the composite grouting technique is introduced，which can take advantage of different grouting technologies and materials. The composite grouting is an economic and effective measure to strengthen the weathered slot to the full extent，which means that grouting in the ground by using different grouting technologies and materials can solve the problems of permeability，strength and stability of the surrounding rock during tunnel excavation according to a special time and space sequence. Based on the characteristic of strong weathered granite stratum，the composite grouting process is simulated by particle flow code(PFC). Then，the composite grouting mechanism is revealed and several grouting reinforcement schemes are proposed. Combining the successful application of composite grouting to weathered slot F1 of Xiamen subsea tunnel，the key technique and evaluation indices of composite grouting for water blockage in weathered slot of subsea tunnel are presented，so as to provide references and guidelines for the engineerings of passing through unfavorable geologic bodies during subsea tunnel construction.

The rupture and movement scope of overlying strata increase sharply since the high strength and rapid exploitation of the longwall mining faces；and the spatial structure formed by fractured strata becomes much more complex. The overlying strata would move and interact coordinately when more workfaces exist；hence leading to mining dynamic disasters that defined as spatial structure instability in this paper. Based on the boundary conditions，three basic forms that named OX，F and T structure are identified，respectively. The OX-F-T evolution of the overlying strata is presented that the O-X fracture is the elemental structure of overlying strata and also the boundary of adjacent workface，one side is OX constitute F structure，and both side with OX is T structure. The characteristics and detailed classifications for each type are elaborated. The microseismic system is used for on-site monitoring，single，double and isolated workfaces that represent the OX，F and T structure are selected respectively to research the distribution rules of seismic events；the results confirmed the OX-F-T spatial structure feature. At last，specialized methods are proposed targeted to workfaces with different spatial structures. The research results provide theoretical guidance for dynamic disaster prevention and control in coal mines.

Triangular meshes are always used in previous lower bound analysis by finite element method. For quadrilateral meshes，the equilibrium equations would be nonlinear on past form. To overcome this shortcoming，the weak form of equilibrium equations are established by integral over the whole elements and the equations are linear，so that，the linear programming can be used. On the other hand，there are less variables and constraint equations for quadrilateral element than triangle element，and so using quadrilateral element is more efficient than using triangle element. Examples show that the results based on quadrilateral elements are more accurate than that of triangle elements，which are consistent with general finite elements.

Based on the detection data of more than twenty large-scale hydropower projects，the wave velocity changes before and after consolidation grouting of rock masses under different conditions of fault fracture zone， weathered zone，and excavation effecting zone are analyzed；and the relationship between the increasing rate of wave velocity after grouting and the wave velocity before grouting is established. Moreover，the relationship between change of wave velocity and deformation parameters of rock mass is discussed. And the comparison between detection data and test results of consolidation grouting for foundation of intake tower in Pubugou hydropower station is carried out. The results show that：(1) The groutability of rock mass is the decisive factor of consolidation grouting effect.(2) Different rock masses have their corresponding fixed ranges of increasing rate of wave velocity. Under confidence interval of 95%，the ranges of increasing rate of wave velocity of fault fracture zone，weathered zone and excavation effecting zone are 14%–38%，10%–25% and 6%–16%，respectively. (3) The relationship between increasing rate of wave velocity and wave velocity before grouting can be used to predict the effect of consolidation grouting.

The complicated wellbore leakage issue has been the major engineering problems in the exploration and production of petroleum industry. In this paper，fracture morphology is obtained by simplifying log data，the influence factors of fracture stress intensity factor K are decomposed and analyzed according to the mechanism；then pressure bearing capacity model of multilayer is established based on the decomposition of influence factors of K，the relationships between pressure bearing capacity，sealing position and sealing particles are calculated and discussed. Through the calculation，it is believed that plugging position has great influence on pressure bearing capacity. The larger the distance from plugging position to fracture tip is，the larger the pressure bearing capacity is. When fracture position is settled，pressure bearing capacity decreases linearly along with the increase of fluid column pressure in wellbore. The smaller the distance from plugging position to fracture tip is，the larger the decreasing amplitude of pressure bearing capacity is. This model can be used for plugging materials selection and optimization of plugging formula. Optimizing plugging particles of different diameters is done through the establishment of fracture width model，plugging formula that suitable for the Jidike Formation of Tarim Oilfield is developed and verified through field test. It is proved that this model is suitable for the field plugging operation.

Based on flow law of fracture water，the permeability and high pressure permeability are studied by Lugeon test，and focusing on the stress relativity of hydraulic property. The results indicate that：(1) The permeability of fractured rock mass is correlative with supporting environment of stress，and very sensitive to stress. (2) Under different stress environments，hydraulic fracturing pressures and fracture fillings，the differences of high pressure permeability properties are large. In addition，based on predecessors′ studies and numerical analysis methods，the hydraulic properties of fractured rock mass such as discontinuity，heterogeneity，anisotropy，preferential flow and size effect are discussed synthetically. Moreover，the hydraulic property and its possible causes are summarized.

Geomaterials in nature have obviously structural characteristics in meso-level，which makes the engineering geological and mechanical properties are more complex than general homogeneous materials. This kind of structural characteristics，on the one hand may reflect the forming mechanism of geomaterials，and on the other hand may also effect the engineering geomechanics of geomaterials and their deformations and failure mechanisms under loading. The quantitative description methods of geomaterial meso-structure are discussed systematically. Taking the soil rock mixture(SRM) as an example，its meso-structure characteristics are studied systematically；and we found that there is very well self-organizing feature of the meso-structure of SRM in statistics level. Based on the studies，the index system used for the quantitative description of the SRM meso-structure is provided，and it is very important to the theoretical study of SRM.

In order to cope with the issue of block identification during the construction process of engineering rock masses containing complex excavation boundaries，a new method for identification of rock blocks is presented based on element reconstruction and aggregation technique. Firstly，the sophisticated mesh gridding technique is employed to establish meshes(e. g. finite element mesh)，thus realizing the accurate simulation of complex excavation boundaries. Then，the modeling method for geological discontinuities based on element reconstruction is employed；thus inserting the geological discontinuities which are widely distributed in rock masses into the meshes. Afterwards，the block construction method based on element aggregation technique and handling procedures for finite structural planes are presented；thus realizing the identification of complex rock blocks based on meshes finally. As the identified block system is defined on meshes，all specific information of block system can be obtained through the elements and nodes of meshes. The visualization of blocks can be also realized using mesh graphic display platform. The validation examples indicate that when the structural planes are considered either infinite or finite，the block identification and corresponding stability analysis results are identical to those derived from common software for block analysis. The presented method is further illustrated with its application to a large-scale hydropower underground cavern complex；and its effectiveness and superiority can be verified. Therefore，the presented method is determined to be a new approach for block analysis，in which complex excavation of engineering rock mass can be considered. Its implementing procedures are totally independent from the traditional topology-based block identification algorithms，thus providing a new tool for block stability analysis.

Aiming at the problem of surrounding rock violent failure of coal roadways with water spraying and gushing and fragmentation roof in the period of supporting and service processes，combining the field investigation，rock and coal experiment，numerical simulation，theoretical analysis and field test， the deformation mechanism of roadway，distribution of surrounding rock displacement field with I-steel support and bolt support and the corresponding dynamic failure characteristics，water spraying quantity of roof borehole，anchoring force test of bolt and cable applying new waterproof anchor agent and control measurement of fragmentation roof are researched systematically. Main contains and conclusions are as follows. (1) The destruction of fragmentation coal roof with water spraying and gushing mainly are the comprehensive actions of partial loading of support structure，invalidation of bolt and cable supporting weaken by water spraying of borehole and bed separation induced by large difference of rigid strengths of roof composite coal structure. (2) The new waterproof resin anchor agent is researched；and its stability performance is proved by both the bolting test in the fragmentation coal roof with water spraying and gushing and the later monitoring results of the cable. (3) The controlling countermeasures for the fragmentation coal roof with water spraying and gushing，which is called as “one system with four aspects”，are proposed；and the corresponding mechanical effect and the function to keep the roof stability of the concrete supporting measures are analyzed. (4) A typical successful case with the comprehensive controlling countermeasures of “one system with four aspects” applied to the fragmentation coal roof with water spraying and gushing is introduced in detail. The research achievements have been adopted in Huozhou mining and have the theoretical and practical values for the support technology of roadways with analogous conditions.

Because of surrounding rock deformation fracture in deep-buried and high geostress conditions，the project problem is very prominent at Jinping II hydropower station underground engineering. The bedded marble which is collected from the Jinping II hydropower station auxiliary traffic tunnel is used for three-point bending experiment on different loading directions with the scanning electron microscope(SEM) high temperature fatigue testing system. The relation between different bedding directions marble?s failure mechanism and strength parameter is analyzed through comparison with homogeneous marble；then the infection to fracture mechanism of surrounding rock by the different loading directions to bedded marble is researched. The results show that the banded structure feature between dolomite mineral particles and calcite mineral particles leads to bedded features of marble；loading direction is the final factor to the fracture mechanism，the failure mechanism of homogeneous marble is that the crack propagation propagate between dolomite mineral particles，when loading direction plumb the bedding；the failure mechanism is coupling fracture with that the cracks penetrate calcite mineral particles and propagate between dolomite mineral particles；and when loading direction parallels to the bedding，the failure mechanism mainly is that the cracks propagate between mineral particles. The difference of strength parameter is disciplinary on macroscopy because of different fracture mechanisms，such as the peak load of homogeneous marble and parallel bedding specimen is 0.58 times and 0.44 times than vertical bedding specimen?s；and the breaking energy is 0.42 times and 0.29 times. The three groups of marble fracture surface as the fracture mechanism? expression on macroscopy has self-similar fractal features.

The degradation law of the damaged rock sample is an important task in the field of rock mechanics. A new method to precast the damaged samples was used. The uniaxial compression tests and triaxial compression tests were made on the samples and the test results were compared with that of intact rock samples which were nearly homogeneous. Under the uniaxial compression，splitting failure was accompanied with slant fracture failure. With the increase of the confining pressure，a new nearly horizontal failure was likely to appear at the cementation area. The strength degradation of the damaged sample to the slant sample increased with the increasing confining pressure，but the increasing range gradually fell. Based on the laboratory test and particle flow code(PFC) numerical software，the size effect of the strength degradation under uniaxial compression on the damaged sample was studied. The research shows that the strength degradation of the uniaxial compression fell with the increase of the height-diameter ratio but had a trend to become gentle. The theoretical model of strength degradation under uniaxial compression was proposed as ，where   is the strength degradation value under uniaxial compression of any damaged sample；  is the strength degradation value under uniaxial compression of the standard damaged sample；  is the height-diameter ratio of the column sample；a and b are the parameters of the material. The theoretical curve is consistent with values from the tests. The calculation result shows that when the size is infinitely indefinitely large，the strength degradation value under uniaxial compression is closer to .

To investigate the progressive failure progress of rock mass with increase of buried depth in super section tunnel，a 3D geomechanical model test system with homogeneous gradient loading and similar material of weak broken surrounding rock and support system were developed. Then the 3D model test was carried out which showed the progressive failure progress of weak broken surrounding rock of entire section method and bench method. Firstly，the weak broken surrounding rock in a range of 200–1 020 m in depth was taken as an example. The strain softening behavior of weak broken surrounding rock and shotcrete can be simulated by different proportion mixtures of iron powder，quartz sand，barite powder and rosin alcohol solutions. Polytef sticks can be used to simulate the bolts. Besides，combining the micro-devices of excavation and construction supporting the construction progress of entire section method and bench method can be well simulated by the 3D model. In addition，the changing information of stresses，displacements and loads in the scope of entire times of the tunnel diameter(0–3 times) can be monitored by fiber grating sensors，resistance strain gauge，multipoint extensometer and micro pressure cells. Secondly，an overloading test was carried out after the end of excavation. The loading gradient was 50 m on the direction of the burial depth until the significant failure characteristics occurred in the no supporting sections. Then the loading gradient was changed to 20 m until the initial shotcrete damaged in large areas. The test results show：(1) The failure zones of rock masses expand with the increase of the burial depth. The no supporting sections fail earliest. Then the failure zones extend to the supporting sections. And the final areas of failure zones decrease gradually. (2) The failure zones of rock masses of no supporting sections and the liner failure zones of supporting sections mainly focus on the crown which is the load sources of the liner failure and the collapse of the surrounding rock. There also exist failure zones on the side walls. The degree of damage increases from the upper part of the side wall to the skewback. (3) The growth rate of displacements in supporting sections is smaller than that in no supporting sections with the increase of burial depth. However，the growth rate of stresses and loads are just opposite. The supporting structures burden the loads obviously. (4) The failure depth of surrounding rocks increase continually in the overloading test. The dynamic pressure arching phenomenon occurs in the scope of crown. Hence，the top reinforcement theory is feasible in theory. The research methods and results will instruct similar engineering.

The time delayed rockburst(TDR) is named based on mechanism and characteristic of rockburst occurring in the diversion tunnels of Jinping II hydropower station；and then it is analyzed and investigated systematically in terms of microseismic and rockburst data in situ. The conclusions are acquired as following：(1) Stress adjusting after rockburst zone is excavated and disturbing outside of stress adjusting range of rockburst zone work together results in the TDR bursting out. 80% of TDR occur from 6 to 30 d after the rockburst zone is excavated and inside of 80 m ranges from tunnel face. (2) All kinds of structural planes，such as joint，fracture，weak intercalation and so on，are main characteristic of surrounding rockmass in rockburst zone，the strike of structure plane is parallel or has a small angle with the axial of the tunnel. (3) As the rockburst zone is excavated，the magnitude and rate of stress adjusting is very large；fracture frequency of surrounding rockmass is quite high；and the microseismic events are located at the same zone in three-dimension space and its number increases continuously with time. Apparent volume of surrounding rock mass has a sudden increasing trend. Energy index has a sudden drop trend in the same time. Before the TDR burst out，microseismic activity has an obviously “sleep” period and the changes of apparent volume and energy index of surrounding rock mass are not very obvious. (4) The tensile，shear and mixed fracture all live during process of rockburst zone excavated. Then the fracture along the structure plane is main trend and tensile fracture is main fracture form. At last，the shear failure is main as the rockburst occurring. A union prevention scheme that firstly the concrete layer with steel fibre is built in time；secondly，the rock bolts are constructed；thirdly，the steel mesh is connected to the surrounding rockmass；lastly， the concrete with steel fibre is built again，which is proposed for TDR，based on the evolution characteristic，law and mechanism of TDR.

Through analyzing the monitoring data of the landslide，it indicates that the monitoring point?s accumulation displacement amounts depended on the monitoring periods，which reflects the characteristics of fractal. At the same time，based on the landslide fissures development process，the motion directions of the landslide internal points are getting uniform，and the motion fractal dimension number reduced. Taking a landslide in Three-Gorge area for example，this landslide is creeping with a constant velocity according to the analysis of the macroscopic deformations. Meanwhile，the fractal dimension numbers of the GPS monitoring points motion trajectory curves are calculated by the box-counting law from 2007 to 2009 year，and the results are all close to 1. The results indicate that the motion directions of the monitoring points become uniform；and the dominant controlling factor plays an important role in the landslide deformation；it is consistent with the reality deformation features. Therefore，the fractal theory applying to the monitoring point?s motion trajectory analysis is an effective way to use the monitoring data to judge and predict the landslide development stage.

The displacement monitoring technology is used more widely in the slope engineering. How to master the slope stability opportunely based on the dynamic monitoring information and determine the impending landslide moment is a key problem for effectively carrying out the landslide warning and avoiding the landslide disaster. On the basis of analyzing various landslide criteria，the displacement acceleration a≥0 is regarded as the impending landslide criterion. The displacement velocity variable generated by the monitored displacement records is regarded as a random variable. It is taken for granted that the displacement velocity variable follows normal distribution in the slope constant velocity deformation stage and is not normal distribution in the slope accelerating deformation stage；then a dynamic identification method of slope impending landslide moment based on Lilliefors testing is proposed. According to the monitoring data in the process of 9•15 landslide of the top slope of Pingzhuang Western Surface Mine，the distribution characteristics of the displacement velocity variables in different stages are tested；the results show that the displacement velocity variables are normal distribution in the constant deformation stage and exponential distribution in the accelerating deformation stage；at the same time，the displacement acceleration variables are normal distribution for some time before the slope sliding sharply，which shows that the rationality of the presented method. The results show that the presented method can identify the impending landslide moment opportunely and accurately，so as to improve the reliability of the landslide early warning effectively.

By summing up the results of case analysis and microseismic monitoring，the three periods during rockburst occurred are pointed out. The types of rockburst are newly divided into centralized static load type and centralized dynamic load type，and engineering structure models of two kinds of rockbursts are established；then，energy criteria of rockburst start-up are analyzed，at last，theory of rockburst start-up during coal mining is put forward. The results show that，the intrinsic factor of rockburst stat-up is the excessive accumulation of static load in near-field system of mining rock；the possible areas of rockburst start-up are the maximum peak areas of stress in the region of limit equilibrium；the process of rockburst of two typical cases of rockburst can be analyzed by using the theory of rockburst start-up；and the time series and spatial series of rockburst are corresponded；so a guidance is provided for detection and prevention of rockburst.

Digital detonator?s delay time is arbitrarily set up according to field requirement and its delay time is very accurate. Digital detonator is one of the most advanced detonators，and is leading the revolution of blasting technology. Several experiments of building tunnels with digital detonator blasting are tried out in Renhechang tunnel of Lanzhou—Chongqing railway，decreasing blasting vibration mechanism with digital detonator is studied. The optimal delay time of blast hole of tunnel is gained；technology of tunnel digital detonator blasting one by one hole is put forward，the blasting vibration is decreased at least 80% in the same blasting advance with detonator blasting with shock-conducting tube，and at least 50% at increasing 25% of blasting advance. Several mixed networks of digital detonator and detonator with shock-conducting tube are tried in order to reduce the blasting cost of tunnel. The optimal joint technology is put forward，the blasting vibration is decreased at least 40% at increasing 25% of blasting advance. The interval between blasting hole delay time greatly affect the result of tunnel blasting，the longer interval between blasting hole delay time result in shorter blasting advance of tunnel and bad fragment，the shorter interval result does not decrease blasting vibration，sometimes increases blasting vibration. The experimental results settle the problem of blasting building railway tunnel in complicated environment，and are also applied to city highway tunnels，the social and economic benefits are acquired. The study result can provide references for tunnel in complicated environment.

With the physical jam phenomenon in water source heat pump injection process as research object，the transportation and deposition processes of suspension particles in porous media are simulated by the self-development sand clogging equipment. In the test，the glass bead particle and gravel particle are taken as the porous media and the alumina is taken as the suspension particle. The flow velocity is controlled from 20 to 200 cm/min. The relationships between water pressure and flow velocity when suspension particles are subsided in glass bead and gravel particles are studied respectively. And the depositional mechanisms for the two different media are analyzed. At the same time，the relationships between relative permeability and time under the conditions of same velocity and different concentrations of suspended particles in glass bead medium are researched. In the end，the permeability coefficient attenuation model is given and it is effective to predict the decrease of permeability coefficient.

When tunnelling in high geostress region，the surrounding rock is often subjected to high geostress，and the increasement of deformation and creep damage for surrounding rock will show clear time effects and nonlinearity. The creep damage evolution of rock is related to its dilatancy which is caused by development of internal mico-crack of rock，and by analyzing the damage energy dissipation in process of dilatancy，a new creep damage evolution equation is established. The creep model of ABAQUS is amended by introducing the creep damage factor，and a new nonlinear creep damage model is obtained. This model is used to analyse the result of triaxial creep test for red sandstone which is got from Yichang—Badong expressway. The back analysis results show that the creep model can describe decay creep，stability creep and accelerate creep of rock in triaxial creep test.

An experimental study was carried out on the compacted samples of Gaomiaozi(GMZ) bentonite. In order to do this，a self-made multifunctional swell and permeability apparatus was developed in the laboratory. The swelling tests and permeability tests were both performed with respect to different initial dry densities and different widths of joints. After hydration tests，the mercury intrusion porosimetry(MIP) test was carried out to study the influencing mechanism of joints on the permeability of bentonite. The results show that the existence of joints will lead to expansion force of bentonite decreases，the permeability increases and thus reduce the self-sealing performance of bentonite in the engineering barrier of repository. During the hydration processes，the existence of joints will change the size and quantity of pores in bentonite and cause its permeability increase macroscopically.

The chamber earth pressure control is a key operation for controlling the impact of the earth pressure balance(EPB) shield excavation on the environment. Based on Shanghai Yingbinsanlu tunnel project constructed by a super-diameter EPB shield，the established mechanism and setting standard of the chamber earth pressure are studied by the theoretical research and measured data analysis. Relationships of the shield construction parameters are studied based on the soil in-out balance concept. The established mechanism of the chamber earth pressure is revealed according to introduce the soil compressing amount at the excavation face. A detailed model of shield cutter head is introduced to analyze the soil compressing amount at the excavation face caused by the cutter head. Based on the concept of controlling the secondary disturbance of the soil at the excavation face，a setting standard of the chamber earth pressure is proposed. The research results are applied and verified in the super-diameter tunnel，monitoring data shows that the settlement caused by shield tunneling construction is controlled effectively.

The mechanism of geosynthetic membrane effect is analyzed by utilizing geometrical and mechanical method，and the stress state of the embankment within the subsidence cupboard is deduced based on an assumption of an idealized slanted sliding surface，and the development of the shearing stress along the sliding surface is considered in the coefficient of active lateral earth pressure. The membrane effect and stress-strain state are coupled in the proposed calculation model. Then，a physical model test was performed to monitor the settlement and induced axial tensile strains of reinforcements，and the earth pressure，etc. A comparison of the test results to the proposed calculation model and several traditional design methods demonstrates that：the proposed method results are more close to the test results，which can take good care of the varying process of relative displacement and realistic slanted sliding surface. Because of different definitions of coefficient of lateral earth pressures，the vertical stress calculated from Terzaghi?s method is small while that from Handy?s method is large；For the strain of geosynthetic，the Giroud?s method is considered to be too conservative and the Esponiza?s is a little small，and the strain calculated from the proposed method is a little large，but it is reasonable when considering the serviceability and long-term creep of the geosynthetic.

Although the conventional Mononobe-Okabe method is widely used in practice，it is only applicable for calculating total limit earth pressure of non-cohesive soil，and not for solving earth pressure distribution. Based on the limit equilibrium theory in this paper，the backfill is treated as a perfectly elastoplastic material which follows the Mohr-Coulomb yield criterion，and a family of slip-lines in the plastic zone is assumed as straight lines，i.e. the plane slip surfaces. The influence factors including inclination of wall，slope angle of backfill，cohesion and internal friction angle of soil，adhesion and external friction angle between wall and soil，surface uniform surcharge，plastic critical depth，horizontal and vertical seismic coefficients are considered. And a more reasonable plastic slip wedge analysis model is established to solve the seismic active earth pressure on retaining wall，the reaction force on slip surface and their distributions by using limit equilibrium method. Furthermore，the geometric and mechanical similarity principle is first presented by means of dimensional analysis. The results show that the total seismic active earth pressure increases with the increasing algebraic value of the horizontal seismic coefficient；but it does not always decrease with the increase of the algebraic value of the vertical seismic coefficient；and it may decrease first and then increase when the horizontal seismic coefficient is rather large.