Non-pillar continuous mining(NPCM) is briefly introduced in an underground metal mine as an example of a new continuous mining method. The pillar of excavation room plays a critical role in the stability status of NPCM. Therefore，probabilistic method (reliability analysis method) is adopted to deal with the uncertainties in rock mass and ore body. By calculating the strength analytically and stress numerically of the pillar，the implicit limit state equation is established，which is different from general limit state equation. To carry out the reliability analysis of pillar，a new Monte-Carlo finite element method based on neural network is needed and presented. Reliability index is obtained to evaluate the pillar¢s performance. The results are proved to be correct by the mining engineers，and the new method is of good application effect and prospect.

The relationships among deformation，stress and damaged state of surrounding rock mass of soft rock tunnel，excavation methods and supporting schemes are studied under the conditions of high geostress and low mechanical parameters of rock mass based on small strain-large deformation theory and 3D FEM. Some useful results are obtained and can be used as theoretic basis for the reasonable construction of tunnel in special area.

In order to solve some NP-hard combinational optimization problems，a new type of simulated evolutionary algorithm，ant colony algorithm is proposed recently. Based on the principles and implementation of the algorithm，the ant colony algorithm is introduced. The traditional algorithm is improved to solve the order combinational optimization problems. The improved algorithm is applied into one kind of combinational optimization problem of construction order for underground house groups. The results of the optimization of construction order for large underground houses show that the application effect of the ant colony algorithm is very good and it is a good method to solve the combinational optimization problems in geotechnical engineering.

Based on the structures and failure characters of rock mass，the two-dimensional physical cellular automata (PCA)，a new model of cellular automata，is set up. The anisotropy，discontinuity of rock mass，etc，are considered in the model，so the failure process of rock mass can be successfully simulated by the PCA model. The proposed model can be used for valuable reference to study the nonlinear features of rock mass.

Based on artificial neural network(ANN)，an identification algorithm of aquifer parameters is proposed according to the observed water heads and flows in seepage field. The practical example of identifying the permeability coefficients of rockmass and concrete curtain is introduced with proposed ANN. The practical application shows that the forecasted water heads approach to observed values while the identified permeability coefficients are introduced to the FEM model.

The stability of unsymmetrically loaded tunnels is studied using four indexes，such as overbreaking of rock，ratio of unsymmetrical load，earthquake rank and stability coefficient. Some original data about each index are collected. The relation between structural stability of unsymmetrically loaded tunnel and original data is established with the help of the information optimization theory，and the tunnel stability is evaluated with these data. The method is proved credible by field measurements.

It is a key link for joint network simulation to produce high precision random number. The direct method to generate random number is simple，accurate and wide-ranging application. The theoretical basement and engineering examples are presented to show the availability in practice.

The block element method (BKEM) and elasto-visco-plastic model are adopted to analyze the deformation and stability of jointed rock slope. BKEM is used to simulate the discontinuous deformation of jointed rock，and the elasto-visco-plastic modeling used in contacted element to investigate the rheological deformation and stability of slope. The computed results show that the method is feasible.

Landslide prediction is an important aspect of prevention and control for geological hazards and the environmental protection. In order to study the nonlinear methods for landslide prediction，the synergetic- bifurcated model of predicting the timing of slope failure is established by combining synergetics with bifurcation theory. Taking the Xintan Landslide as an example，the prediction of landslide is carried out based on the model suggested.

The landslide is considered as a consequence of catastrophic slide of initially stationary or creeping slope triggered by a small perturbation，such as the effect of rainfall. Presuming that slope is shallow and infinitely long and the slip surface is made up of elasto-brittle medium and strain-softening medium，a cusp model of two control parameters，a and b，is formulated with simple law of mechanics. A fully catastrophe analysis is done for all possible scenarios when a continuous change is imposed to the control parameters. As the slip surface is continuous and erosion due to rainfall occurs，the control parameters of the slip surface may evolve such that a previously stable slope may become unstable (e.g. catastrophe occurs)，with a small perturbation imposed. Thus the present analysis offers a plausible explanation to why slope failure occurs at a particular rainfall，which is not the largest in the history of the slope. Through catastrophe analysis，it is also found that a complete evolution of landslide includes five stages：stable～slowing slide～uniform slide～accelerating slide～catastrophic slide.

Duncan-Chang model is introduced into the constitutive relationship of saturated-unsaturated soils，and the nonlinear elastic model for this kind of soils is established，and is used for the analysis on the landslide during rainfall. Example analysis shows that it is feasible and beneficial to use this model for the analysis of soil landslide during rainfall.

For the aspect of forecast and prediction on geology disaster，the visual simulation technique of geology disaster feature is presented and studied. Combining with practice disaster data，visual simulation of geology disaster feature and the features of slope distortion reproduction with reality using computer simulation technique are processed successfully. In order to forecast and predict better geology disaster，the favorable gist are also presented.

The different distribution functions of the landslide-thrust and the resistance of soil or rock are studied and deduced based on the results of model test and field test of antislide piles in China. Meanwhile，to be convenient，the study results are provided with a table. Generally speaking，compared with the distribution diagrams that people are accustomed to using at present，the presented results show that the resultand thrust point becomes lower and the resultand resistance point higher，which coincides with the practical state of forces acting on antislide piles. An example shows that the design of antislide piles will be more economical and reasonable by choosing appropriate distribution functions. Therefore，the design level of landslide control will be improved.

In order to study the mechanism of high-speed sliding of large-scale landslides，frictional tests are carried out for the basalt samples under different conditions. It is proved that the normal pressure on the sliding surface，sliding velocity and surface characteristic have influence on variety laws of frictional coefficient on the sliding surface.

In order to investigate the macroscopic mechanics effects of chemical kinetics of water-rock interaction on the deformation and failure，the calcic rock，red sandstone and granite reacting chemically with different aqueous solution at atmospheric temperature and atmospheric pressure are uniaxially compressed. The quantitative results concerning the changes of uniaxially compressive strength under different conditions are obtained. The mechanical effects of water on rock are closely related to the chemical action of water-rock or the chemical damage in rock. The intensity of chemical damage is proportional to the intensity of chemical action in water-rock system. The mechanical effect of the chemical action of water on rock is time-dependent. The primary factors influencing chemical damage in rock consist of the chemical property of rock and aqueous solution，the structure or homogeneity of rocks，the flow velocity of aqueous solution passing through rock，and the cause of formation or evolution of rock.

The stress in the roof of karst cave is analyzed and calculated by three-dimensional finite element method. The relation among the critical value of distance from pile foot to karst cave top，the karst cave sizes and design load of single pile can be obtained by means of multivariable linear regression method. Finally，the reliability of the regression equation is verified by engineering example.

The fault zones consist of main discontinuities with low dip angle in the dam foundation rockmasses of Xiluodu hydroelectric station. Therefore，investigating the characteristic of seepage in fault zones can instruct the design of impervious curtain in the dam foundation. The in-situ seepage tests in fault zones and their results are introduced. The factors affecting the permeability，critical gradient，failure gradient and the procedure of seepage are analyzed.

A new technique，supporting funnel method，is introduced to recover and controll large-scale collapse in main shaft. The key points of the technique involve a box shaped beam acting as a supporting structure bridge through caved area to recover its download function. An inverse cone shaped funnel built at lower level of the shaft has multi-function of storage，ore transportation，and supporting the upper and surrounding rockmass of the shaft. The method keeps the whole system stable by local reinforcement for the collapsed shaft. The technique fully recovers the system function and make the shaft stable. This makes a breakthrough of conventional concept of structural design.

Crack starting and developing time，and the law of crack developing with multi-hole blasting are analyzed. The formula of crack developing velocity at hole wall with different blasting methods and charge structure is proposed. The condition of crack length and number produced by blasting is expounded.

The hole depth (charge length) is one of the factors to influence the character of blast wave in rock. Using the difference code SMMIC developed by the authors，the spread process of the blast wave in the vertical hole with single free surface is analysed. The results indicate that the decay coefficient of the peak value of blast wave with the distance will be reduced as the hole depth (charge length) is increased. The decay coefficients of the peak value of blast wave with the distance are 1.35 and 1.56 corresponding to 4 m and 2 m deep holes respectively.

The parameter decision and failure criteria in the dynamic FEM modeling on anti-explosion of reinforced concrete structure are discussed. The explosion loads are obtained by DYNA FEM. Using FEM optimization technology，the anti-explosion ability of reinforced concrete hollow cylinders is analyzed. The results are consistent with chemical explosion experiment.

Based on relevant assumptions，several governing equations are derived and the equation of saturated liquefaction in granular media is educed. The potential vector equation and the velocity expression of three kinds of body waves under the conditions of no dissipation，as well as the general equation of potential vector and the attenuation coefficients of P wave and S wave under the conditions of dissipation are deduced. By the vibrating liquefaction experiment of tailings and fine iron ores，the change of pore water pressure is observed and noted when the vibrating liquefaction takes place. With the infliction of vibration，the pore water pressure is increased with wave motion. Using the wave theory and experimental results，the influence of three body waves is analyzed in details on pore water pressure，and the mechanism of pore water pressure and the wave mechanism of vibrating liquefaction are revealed.

Some methods of volume visualization are described to construct 3D stratum model. Three examples of volume elements are given and the techniques using them are illustrated. Through using the volume elements，3D model is built and the section and incision of stratum model become easy. At last，a practical application which use prism as the volume element is presented. It shows that the volume visualization is effective in geology of civil engineering.

As the traditional ore-drawing theory does not consider the effects of the low ore height，large opening，inclined drawing and the continuously moving of support，its application in longwall sublevel caving mining of coalmine is limited. Considering the structure and position of hydraulic support and its drawing opening，the problems are analyzed of loose top-coal moving on high-window，middle-window or low-caving- door support. A new concept of arc-ellipsoid is suggested with corresponding equations to describe the transfor- ming relation of drawn body shapes of loose top-coal on high-window support. With the help of co-moving coordinate system and the new concept of average deviation of the drawn body axis，the motion formulas of middle-window of low-caving-door support are also given to present the change of the average contacting position of drawn coal and refuse with different caving quantities.

The vibration problem of pile with variable sections and finite length under exciting force is studied. The influence of the soil under pile toe and surrounding pile is considered. With Laplace transforms，the analytical solutions on the velocity mobility and the dynamic stiffness at the head of the pile are derived. Based on the solutions，the influences of degree and length as well as location of pile defects on the vibration properties are studied.

By using integral equation method，the dynamic response of the laterally loaded pile in saturated soil is studied. Utilizing the Green function of harmonic horizontal circular load in the interior of half-space saturated soil and compatibility condition between pile and soil，the second kind of Fredholm integral equation is established. After the numerical solution of the integral equation，the dynamic response of the pile subject to harmonic horizontal load can be obtained.

Based on the theoretical analysis and testing results，it is proved that there is fixing resonance of sensor to affect the results of low-pile. The condition to induce vibration disturbance is given，so that the available measure could be adopted to obtain the right information from pile testing.

Using elasto-plastic model and elastic mechanics theory，the stress transfer and deformation of pile along the pile are analysed respectively. The calculation model of single pile is built and the theoretic solutions are gained. The increase of bearing capacity of single pile is obvious with time. According to the data of static loading test for single cement soil pile，the time effect on bearing capacity of single cement soil pile is analysed in the saturated soil. The influences of groundwater on the bearing capacity are considered too. The presented results are of important significance to optimizing design of the cement soil pile composite foundation and deciding the time of the loading test.

Based on the investigation of creep behavior of salt rock，the mechanism of casing failure and well-hole unstability resulting from the creep of salt rock in the deep salt rock stratum are investigated. The suitable numerical model is proposed in order to analyze the creep pressure on the casing. The analysis of creep pressure on the casing at the Tilimu basin of Xinjiang is carried out. The research results show the consistency between the calculation results and the practical measurement in the field.

The improved Gauss-Newton-Marquit method is proposed for back analysis of elastic displacement for underground tunnel. The direct solution method of partial derivative is used in stochastic finite element method to complete the back analysis. Compared to the traditional Gauss-Newton-Marquit method using difference method，the efficiency of the improved method is greatly advanced. The case study shows that the improved method is more efficient in solving the back analysis problem of elastic displacement for underground tunnel and is expected to be applied to large engineering practice.