This paper discussed the development of heat extraction in hot dry rock，presented a thermo-hydro- mechanical coupled mathematical model for 3D rock matrix-fractured medium and the detailed strategy and methods to solve this mathematics model，carried out detailed 3D numerical simulation for exploitation in deep-seated HDR 6 000 m under the surface. The following are revealed：(1) drop of rock temperature with the heat extraction and the distribution variation；(2) reduction of stress within the matrices and fractures with the heat extraction；(3) the variation of aperture of fracture with the heat extraction. This paper offers the foundation and methods for the decision and project selection in the heat exploitation of deep-seated HDR.

Block Theory，which is developed in recent ten years and more，is an effective and reliable method for jointed rock mass stability analysis. The sliding of jointed rock mass surrounding a cave is correlative with the distribution and mechanical character of rock joint，and the sliding pattern is also important for the maintenance of a cave. Based on the established stereoanalytic method for Block Theory，the stability of a cave for winding engine in a mine is analyzed. Moreover，the movable blocks are determined by this method and effective measures are also suggested for reinforcement.

RQD has been used widely in projects to evaluate the rock mass properties. And it has been listed in the relevant codes. However，because traditional RQD by Deere has many limitations in applications in projects，conception of generalized RQD under different threshold values was introduced. It has been applied to evaluate stability of rock mass，combine with 3D network simulation technique of discontinuities. And better RQD results have been obtained with the use in projects.

The discontinuous deformation analysis method for forward modeling is extended to three-dimensional cases. Just as in the two-dimensional discontinuous deformation analysis，each block has linear displacement function or constant strains and the equilibrium equations are established by minimizing the total potential energy. The elastic submatrices，the loading submatrices，the inertia submatrices and the contact submatrices are derived and added to the global equations. Two examples are computed and the numerical results indicate the proposed forward model is correct and valid.

First of all，a representative element is taken theoretically from the orthotropic rock reinforced by systematic rock bolts，then according to the concept of ‘equivalent material’ and under some simplified conditions，the relevant constitutive expression and the failure criterion as well as one kind of viscoelastic-viscoplastic model for the bolted rock are set up and a 3D FEM code is introduced. Through the calculation examples of an underground opening the rheological states of the surrounding rock without and with bolting are investigated，and some conclusions are given finally.

During the construction of a tunnel，if no measure is adopted to prevent groundwater discharge，the movement of groundwater along tunnel axis can be ignored and the seepage movement of groundwater can be simplified to 2D movement in section after completion of the tunnel. If the size of a deep tunnel is far less than that of its surrounding aquifer，it can be treated as a point-well in section. Trial calculation is performed by putting a value of discharge，estimated by analogy，into the numerical model and by repeated increases or decrease in a certain step until the groundwater table reaches the stable state. Then a trial discharge can be obtained. The discharge of a deep tunnel in southwest China calculated by the trial method accords well with results of other methods and its significance of hydro-geology is more clear，when used together with experimental and analytical methods. The value of discharge can be calculated more precisely，and this indicates that it can be used practically.

The influence of multiple kinds of matching of tectonically controlled fissures and the roadway layout on the stability of mining roadway were studied. The effects of fissure spacing(I)，the inclination of fissure，the angle of the fissure bearing with the roadway axison the convergence deformation of the roadway surrounding rocks were analyzed. And the layout principle of matching of fissure and roadway axis for guaranteeing the stability and maintenance of the roadway under the condition of technically controlled connected fissures was proposed.

Seismic tomography is applied in exploring the cryptostructure and fracture of longwall top-coal caving face in Xinji Coal Mine，Huainan City，Anhui Province. Based on comparison of information in exploration and mining，it is proved that the blind faults have evident linear image of seismic tomography，which is in good correspondence with the practice. The area of thickened coal seam also is shown in the image of seismic tomography. Wide application of seismic tomography in coal industry is one of effective ways to ensure high productivity and high efficiency of longwall top-coal caving face.

Water content is an essential factor to mechanical properties of rock creep. In this paper，through the results of creep tests of dry and saturated rock specimens under different uniaxial compressive stress，the law of how the water content affects the mechanical properties of rock creep is studied. Then，according to Generalized Kelvin Model，the parameters of rock creep are attained and analyzed under different water contents and different compressive stress levels.

The constitutive model Hou/Lux，based on continuum damage mechanics and on the material model Lubby2 is presented and the damage，the healing of damage，the tertiary creep and the creep rupture of rock salt described. An application shows how phenomena observed in laboratory tests on axially perforated cylinder sample， such as softening， dilatancy， spalling and radial deformation into the axial bore as well as spalling can be numerically simulated with the model Hou/Lux. Furthermore，it is then evaluated against the measured permeability and stress profiles of a 37-year-old drift at the Sondershausen minein，Germany. Satisfactory agreement is obtained between the calculated and measured data.

By means of 3D FEM non-linear analysis of an arch dam having a dam toe with developed geological structure, the influence is discussed of temperature，seepage，terrain and geological flaws in the foundation on the arch dam and mechanical behaviors of foundation when the dam is working. The distribution of the displacement field，and the stress field of the arch dam with complex foundation and characteristics of the transmission of forces are given. The mechanism of the generation，form and development of plasticity domain in dam and bedrock are analyzed.

Mechanism of some serions rock caving cases in rock bolted coal roadway is very complex. There are mainly two reasons：the one is the uncertainty of physical parameters and mechanical characteristics of surrounding-rock，and the other is that various calculation models used for analyzing the stability of surrounding-rock in roadway only partly reflect the mechanical behaviors of surrounding-rock. To improve design approach based on safety coefficient and to consider stochastic factors as mentioned above，based on a model of loose weight for rock-mass of underground pressure theory and a principle of resistance force development in structure supported by rock-bolt，the paper researched calculation methods of resistance force and load in limite state equation which was used to calculated stability degree of surrounding-rock in coal supported by rock-bolt. A stability reliability degree for surrounding-rock of a underground roadway in coal supported by rock-bolt has been calculated，and the conclusion is that failure probability about l0 percent of surrounding-rock in a rock-bolt supported coal roadway is acceptable.

This paper is a part of experimental study achievement gained on mine sites of Jincheng bureau and Huainan bureau. Anchoring force of bolt，pulling force of pull rod，upward force of pull rod，the surface displacement of tunnel，and the displacement in the depth of surrounding rocks were measured. The data are necessary for the study on supporting effect by truss.

Factors that should be taken into account in shield selection were analyzed and the flow-chart of shield selection was established in this paper. The cutting mechanism of cutterhead was also described. Then，one of shield advancing cases of Guangzhou metro No.2 was illustrated to describe the shield selection and ground adaptability. The conclusions were that full face disc cutters are not suitable for completely weathered rock No.6 and No.8 but suitable for slightly weathered rock No.9 with advancing speed 0.5 mm/d and 2～4 mm/d respectively. On the contrary，the full face rip teeth cutters are suitable for rocks No.6 and No.8，and not for slightly weathered rock No.9，with the advancing speed 8～10 mm/d and 4～7 mm/d，respectively.

In this paper，according to a vast amount of building engineering monitoring data，the relationship between non-uniform settlement of building foundation and rock stratum dip angle has been systematically analysed. Mathematical models of relationship between non-uniform settlement of building foundation and rock stratum dip angle has been given.

Aiming at the characteristics and current situation of model experiment，sources of experimental errors are analyzed from the point of view of equivalent theorem，equivalent material，boundary condition，temperature and humidity. The experimental errors are divided into three types：controllable，amendable and unavoidable. The pattern of movement distribution caused by compression and splitting on the model boundary is studied. Theoretical solutions are suitable to amend the abnormal curve of measured experimental data and helpful to improve the accuracy of model experiment.

The effect of rainfall on landslide is a widely discussed theme. This paper expatiates the inspiring cause from some aspects such as the substance composition，structure conditions，rainfalls，rainfall density and the stress characteristics etc. We have observed the course inspired by artificial rainfall from the large outdoor landslide experiment. The indoor experiment illuminates that the cohesion and inner friction angle have a chop relationship with the moisture content. The gravel slope landslide is inspired by many factors of which the rainfall is the dominant.

The rock displacements and energy distribution at different bench hights in open-pit mine bench blasting were studied by 3D FEM. The problems that may appear in bench blasting were discussed. The results indicated that if the bench height is increased properly，the percent of large-scale stones may be decreased. The piles of blasted rock blocks large in size are intensively lowered in number and loading becomes easy，so the efficiency of mining equipment can be advanced. But the fact that sometimes toe rock may appear should be noted.

The coupling method of MSARMA，a method for evaluation of slope stability with Monte Carlo Method is described. It is a good method to couple deterministic theory and non-deterministic theory. This method is suitable for the stability evaluation of high and steep slope with complex rock structure.

In order to reduce dense radial cracks around charge and facilitate required crack in control blasting，the measures to be taken are to depress the function of blasting stress wave and increase acting time of explosion gas，i.e. to adopt decoupling charge. This paper analyses relationship between decoupling index Kd and blasting action. Based on both laboratory and in-situ experiments，it is concluded that furthest length of blasting crack occurs at Kd = 1.67 and number of cracks decreases with increase of decoupling index.

By means of concrete liquid returning to ground，beams between piles are formed in the process of composite foundation construction，which can reduce pollution of the environment and improve the bearing capability and resistance to deformation of composite foundation. In the paper，a whole process of formation of composite foundation is simulated by an example of a freeway. Composite roadbed with beams between piles is analyzed and compared with the case of no beams. The obtained results are of value for engineering reference.

The method of load transmission for deformation analysis of single pile is revised. On this basis，a perfected FEM simulation method is presented which can simulate the interaction between a rock-socked pile and rock or soil in soft rock. The transmission function is introduced in contact elements and the boundary conditions are treated by infinite elements. The influence of sediment is also considered. A computer program has been developed. We calculated and compared results with measured data，then used them to simulate a rock-socked pile in mud-sandstone around Nanning region. The results show that it is rational and feasible to use this program to simulate and analyze a single pile in soft rock. The simulated results give guidelines for construction and design of soft rock-socked piles.

It is an important measurement in decreasing mining-caused land destruction by building super-high bench dumping-site. Foundation loading，stability analysis，mud-rock-flow and water control are key factors in decision making. By the new study，a great scale dumping-site in Qijiagou of Changba，which is 400 m high has been built. Meanwhile，mechanism of foundation loading，technology of determining the limit height of dumping-site，corresponding stability analysis，and a new method of controlling mud-rock flow by controlling small and tiny grains have been developed. The first sluiceway of dumping-site has been built successfully in our country. Afterward，these techniques have been developed widely in Miaoergou dumping-site of Nanfen. Better effects have been obtained. Therefore，this technique can be used widely for reference in other mines.

Rock-like materials have high compressive strength，but low tensile one. Testing study is made on a express highway for improving these material characteristics to meet the engineering requirement. The prestressed concrete girder is pulled，and three types of load，that is，the fixed load in the middle of the girder，well-distributed and point loads on the girder，are exerted. The working characteristics of prestressed concrete girder under the states of elasto-placticity are discussed. Experience for the design of prestressed concrete girder has been accumulated and mechanical behaviors of rock-like materials have been investigated.

According to the example of a project of heavy tamping treatment for foundation with a thick layer of recently deposited miscellaneous fill containing mud，a consolidation method of “precompression before tamping”is presented：the tamping is light first and then becomes weightier and weightier with energy gradually added. The article analyses the effect of heavy tamping treatment of foundation of recently deposited miscellaneous fill on the basis of the quality test after heavy tamping and long-term survey after constructing. And the foundation bear capacity after heavy tamping and effective treatment depth of heavy tamping are then evaluated.

The soft foundations of expressway must be strengthened to keep the settlement within the permitting value especially for the high road embankment. There are many engineering methods to strengthen soft foundations，and the expense，result，and construction period are different for different methods. The vacuum-mound preloading method is one of these methods that have many advantages such as low expense，short construction period，and good effect to very soft soils. This method has been used in many kinds of engineering project to strengthen the soft foundations. At a test section at Nanjing-Jingjiang-Yancheng expressway has been used the vacuum-mound preloading method，the effect and valid depth become known through the test results. The conclusions are useful for spreading this method in the expressway construction.

SMW retaining structure is of many good properties，such as good characteristics in watertight，simplicity in structure，quick construction，no effect on environment，low cost，and so on. According to the case of Xianhe bridge pump station in Zhenjiang，three structural analysis methods including the equivalence girder，the fixed supporting force of excavation and brace layer by layer and the elastic girder calculating method，are first introduced，and their fitness are then discussed. According to the calculating results，the fixed supporting force of excavation and brace layer by layer calculating method are comparatively suitable for practical construction.

The forms of general solution for frequency domain and correlative frequency equations for both the perfect piles and the defect piles are put forward. In addition，the research on the effect of various types of pile and defect on the basic frequency of the whole pile is performed.

Under the condition of inverted filter protection，the crack self-healing of dispersive clay core for a reservior in Xinjiang Province is systematially investigated. Results show that the dispersive clay can be used to build core directly without improvements. Even the perfoliate crack can be self-healed if a good filter is provided downstream of the core.

In this paper，the drilling core examination data of 192 DJM piles in the Suzhou-Jiaxing-Hangzhou freeway project are analyzed. The adjusting indices and standards of construction quality in drilling core examination of DJM piles are discussed.

A large number of rock mass quality classification systems have been put forward in the world. Recent advances in this field at home and abroad are reviewed systemically in this paper. The relationship between rock mass structure， rock mass quality and its classification is summarized. Finally，a relation of interrelation，comparison and conversion among the main rock mass quality classification systems are proposed.

The figure of Rankine active earth pressure in clayey soil is corrected. And the cohesion stress region in it is conformed. Various incorrect statements of cohesion on that part are put right. At last，the steps in design of retaining wall in clayey soil are given.

The loading test of composite foundation reflects the comprehensive bearing capacity and characters of pile and soil. Due to the non-uniformity and uncertainty of composite foundation，the types of loading test curves differ greatly. On the basis of engineering practice and according to relevant theories and norms the paper has analyzed the standard of bearing capacity determination by loading test of composite foundation with cement soil mixed pile. Finally，the relative deformation and rebound methods are suggested to determine bearing capacity.