The flattened Brazilian disk specimen is proposed to determine elastic modulus，tensile strength and opening mode fracture toughness for brittle rocks in one test simultaneously. According to the results of stress analysis and Griffith’s strength criteria，in order to guarantee crack initiation at the center of the specimen，the loading angle must be greater than a critical value (≥20°)，and hence the minimum relative value of flatten width should be decided accordingly. Based on the recorded load-displacement curve of the specimen’s whole fracture process (including the recorded process after the maximum load)，the theoretical analysis shows that can be determined by the initial linear section， can be determined by the maximum load，and by the minimum load immediately subsequent to the maximum load. The relevant formulas for the calculation of are presented，and the key coefficients in these formulas are calibrated by strict finite element analysis. Some approximate analytical formulas based on mechanics of elasticity are also provided，and their accuracy is demonstrated by the finite element analysis，hence the results obtained from these formulas are reliable.

The influence of stratum of Sichuan region on oil-well casing shows that casing of deep well suffers from overload and is damaged in short time as creep and flow of salt rock，such as well Guangshen 1 and well Zuo 3. Their economical loss is very serious. Therefore，the study on creep rule of salt rock stratum is an important base work. For this reason，an ordinary triaxial stress test device with controlled temperature and pressure is developed. The project includes a set of ordinary triaxial creep experiments for salt rock. The creep characteristic curves and parameters are gotten. The constitutive model of salt rock material is fitted out. Those provide some scientific basis for casing strength design. Then，the effect of mechanical behavior of sale rock stratum on casing is analyzed by finite element method. The relation between creep load of casing and some important parameters is given，which include depth of well，in-situ stress and uniformity coefficient of in-situ stress. These consequences are of significance to practice.

The measurement method and testing results of deformability of weak bathlite are presented. The factors causing deviation in testing results are considered. Correct identification and evaluation of weak rock deformability are made and the result is of great importance for the design of arch dams.

By statistically analysing dip angle，linear density or spacing and thickness of the weak interfaces existing in quasi-lamellar structure basalt rock mass，the necessary weaking parameters of basic rock mass deformation modulus are obtained considering the effect of weak interbed thickness. Through thickness weighted average and deformation equivalence，the horizontal and vertical deformation modula of synthetic rock mass are obtained.

E′mei Mountain basalt is a common kind of rock in southwest china and often found in hydropower engineering construction. The rock mass texture and engineering property are obviously influenced by the primary formation，tectonism，weathering and unloading of basalt. Bedding structure and bedding joint formed in rock formation are the basis of inter-formational and intra-formational shear fractures. Joints affect the integrity and structure of rock masses. The effects of joints on the rock mass mechanical properties can be shown by in-situ tests. The inter-fomational and intra-formational shear fractures govern framework structure and engineering property of rock masses，and consist of the major geological boundaries in many engineering geological problems. Their influences on the mechanical properties of engineering rock masses are shown in structure effect and mechanic parameters by quality classification of rock masses and loading analysis.

For measuring and analyzing the permeability of inhomogeneous reservoir rock in laboratory，an automatic fitting model is built to calculate the permeability of inhomogeneous reservoir rock based on the test data of whole core analysis and the mathematical model describing unsteady flow in one-dimensional inhomogeneous porous medium. The gradient of objective function is calculated by means of adjoining function and the auto-match model is solved by sequential quadratic programming methods. The feasibility and reliability of the method are proved by examples.

Initial stress is one of the key factors influencing stability of slope，underground cavity and foundation rock mass，and is one of the elementary indexes required in engineering design，especially in large hydroelectric engineering. By using 3-D elastoplasticity FEM，the initial stress field in a large hydropower project on Jinsha River is simulated and fitted. The result shows that the calculations fit well with in-situ measuring data and can satisfy design need. The fitting is better for than that for .

High stress rock burst and water outburst occurred in Erlangshan and Huayingshan road tunnels separately. The ground stress surveying，rock mass deformation monitoring in Erlangshan tunnel，and study of the characteristics，influence factors of water outburst in Huayingshan tunnel are presented. Some countermeasures against rock burst and water outburst are also proposed.

Qingling tunnel with a length of 18 km is a control engineering on Xi′an-Ankang railway line. Rockburst with different intensities occurred in 43 sections during tunnel construction. The characteristics of rockburst are described. The mechanism and multiple criteria of rockburst are identified by means of deformation and destroy experiments of compound gneiss and by analysing the forming conditions of rockburst.

For the utility of underground space，the number of closely spaced two-tube tunnels gets more and more. Different excavation sequence makes the results different. The second tunnel is constructed in the ground disturbed by the first one，so that the ground stiffness is unsymmetrical. The construction of the second tunnel has effect on the first excavated one，which is related to the distance between two tunnels and the method of excavation and lining. The ANSYS program is used to analyze the laws of the settlements of the surface and arch，under the conditions of different distances between tunnels and different methods of excavation and lining. The results show that the excavation of second tunnel has significant effect on the first tunnel.

When building double-hole urban tunnels，the interval is hard to meet the demand of normal design code because of the terrain′s limits of the city. In order to investigate the influence of different surrounding rocks，double-hole tunnel interval and supporting on tunnel stability，a series of calculations and analyses are carried out by using 2-D FEM，and the reference values of the minimum interval of double-hole urban tunnel are obtained. Also，the rock stability of Xianyueshan tunnel in Xiamen is analyzed.

Numerous tunnels are adopted in railway and highway in western mountainous areas，China. The external water pressure and flow are the most important problems faced in the tunnel construction. In order to calculate the high external water pressure，the rock seepage field and external water pressure coefficient should be treated in detail. External water pressure can be calculated independently or together with confining pressure. The basic theory and method calculating external water pressure are discussed with an example.

The geological background of karst water outburst，karst distribution，seepage flow field of karst water and recharge source of karst water outburst in the long Huayingshan twin highway tunnel are systematically described. The researches provide basis for treatment of water disaster.

With the development of the tunneling engineering，the applicationg of TBM will play a more important role in tunnel construction. As a matter of fact，the traditional surrounding rockmass classification can not meet the need of tunnel construction by TBM and the study of surrounding rockmass classification in tunnel excavation with TBM is necessary. Such a surrounding rockmass classification method is proposed with the practice in construction of Qinling tunnel and Xian—Ankang railway line.

The structure and shape of slope are the important condition to cause landslide. The 14 kinds of landslide structures and 2 kinds of methods to determine dangerous slope shpae are summed up. The study result can be a base to estimate the stability of slope.

For a large landslide，a new form of retaining structure，which is an integral structure of piles and boxed tuunel，is applied. Simulation technique is used to simulate the integral structure，construction sequence，boundary conditions and the effect of boundary condition variations. The model of structure analysis and calculation is established and used in structural calculation of static and dynamic states. The results are applied in the engineering design and construction.

Visualized hazard assessment of landslide is an important direction of researches and applications. The calibration-free augmented reality for landslide visualization is presented for the first time，and the feasibility for the landslide visualization is demonstrated. Compared with traditional virtual reality，the new method can not only present more realistic results，but also enhance efficiency greatly.

A roadbed subsidence pattern for predicting the security of roadbed in ground subsidence area with complicated structure strata and any shape of excavations is proposed in this paper. The methods for computing the values of the movements and deformations of the roadbed characteristic points are investigated. The calculating formulae for predicting the roadbed subsidence，inclined deformation，curvature deformation，horizontal displacement and horizontal deformation are provided. The methods for evaluating roadbed security and predicting disastrous accidents of roadbed in ground subsidence area are also discussed. Finally，a practical example is given for applying the method to evaluate roadbed security.

The main dynamic information from design and construction of high rock slope is analyzed. The spiral cycle design and construction mode is proposed，which can be categorized as dynamic design and construction. The main process of dynamic design and construction of a practical project is discussed in detail and satisfactory result is obtained.

The formation mechanism and optimal control design of East Hill landslide at Zhujiabaobao iron mine is discussed. The technological sequence is as following：field investigation，test of rock mechanics，analysis of deformation mechanism，check analysis by limiting equilibrum method，evaluation of slope stability and dynamic design. On the basis of the above results，the optimal control plan is determined. The engineering structure of bolting is designed using the computer programming method.

The evaluation method of system stability of rock and soil slopes is analyzed using numerical analysis. Then the main weaknesses of the primary evaluation method are pointed out and the new thought to evaluate the stability of the rock and soil slope system is proposed and discussed.

Analysing the character of internal forces of anchor cable frame by Winkler model，and verifying it by field test，a calculation method is put forward based on elastic foundation beam. Result shows that the method is closer to the fact than the old method and can optimize the design of anchor cable frame.

FLAC3D (Fast Lagrangian Analysis of Continua in 3 Dimensions)，developed by Itasca Consulting Group.Inc.，USA，is a widely used computational package in the world. Since FLAC3D is operated normally through commands，it takes considerable time to build complex computation models. The fundamental principles and characteristics of a pre-processing program for FLAC3D are discussed in detail based on the primitive meshes provided by FLAC3D. Meanwhile，in order to verify the program，an example of simulation procedures and results is given.

Several groups of scraping tests for rock by single insert are made. The conical and chisel inserts and dolomite，limestone，sandstone，shale are involved in the tests. The tests are performed by Rock Bit Lab of South- west Petroleum Institute. The principle of tests，the method of geometric modeling，which is important for computer simulation research on rock-bit penetrating procedure，and the interpretation of scraping test data are all presented. Some related problems are also discussed.

The exploration process，size distribution，characteristics and permeability of anti-seepage material used for earth-rockfill dams of Pubugou Hydroelectric Plant are explained in brief. The research result shows that after delotion of coarse grains above 80 mm，the conglomerated earthern material found in Heima district No.1 can be used as antinseepage material for dam core wall with satisfactory permeability and compressibility.

Vegetation acting on slope stability and its surface layer erosion control are analyzed in light of mechanics and hydrology. Based on analysis of greening methods for rock slope in some new-built highway projects in South and Southwest China，the advantages and disadvantages of different greening methods are discussed. Also，some experiences are accumulated to perfect greening methods for rock slope.

The landformation and geological conditions in the mountain area of the southwest China are very complex. Several special geological problems of weak rock，such as expansion of mudstone，stability of slope in fractured weak rock，soft soil properties of the carbonaceous shale under special environ-ment，are presented，and some prevention measures are suggested.

The subgrade in Nanning-Kunming railway is very long and engineering conditions are complicated there. One of the key techniques is subgrade slope engineering in construction of the railway. Therefore，test and research on subgrade treatment of cataclastic expansive rock，retaining and protection of high cut slope in crushing and weak rock，and new retaining structure types of high embankment slope，such as piles-plate wall of prestressed anchor wire，reinforced earth retaining wall of new type straps，are conducted in combination with construction of the railway. Outstanding achievements of above research provide scientific foundation for smooth construction and safe transport of the railway.

The settlement，lateral displacement，stress ratio of pile versus soil of three soft soil consolidation schemes of in-situ experiment using cement-mixed pile for Xiao-Yong railway embankment are analyzed. The conclusion drawn is that the short cement-mixed pile scheme is the best both in technology and economy.

The design procedures of the Soil Nail Support Formwork Wall Technique(SNSFWT) and the control of method slope deformation are presented through an engineering example. The successful experience shows that SNSFWT is of good application prospect.

An engineering case study is presented for application of vibration and substitution method in reinforce- ment of cohesive soil foundation. It has been proved that bearing capacity of composite ground confirms the design specification. Several quality problems are also discussed.