Through the analysis of coal creeping feature, the paper proved that quintic rheological model with adhesiveness, elasticity and plasticity functions well in describing the creeping. On consideration of the power of coal gas, it was figured out the state law of the creeping of coal with gas. It is found that creeping occurs to coal in certain situation because the stress on uncovering coal plane has changed from three-dimensional stress to dichroic. If coal is two-way stressed, the strain on the direction of uncovering plane is tension strain; and this tension strain of the coal on the uncovering plane excesses that level of coal breaking up, the creep collapsing happens. With this method, it can be predicted the time of creep collapsing on uncovering coal plane. The method can also explain the mechanics of rock collapsing in engineering by this way.

According to the surrounding rockmass deformation parameters, the movement law of overlying strata and the distribution of rock stresses will be obtained which will be beneficial to engineering and management. Based on the geology and engineering conditions of rockmass in tunnel, the mechanical model of two parameters elastoplastic foundation beam is proposed and the space curve differential equations, the foundation beam differential equations are analyzed. This model is valuable to research the dynamical phenomenon, such as the rockburst and failure phenomena at working face; so it will be a basis to predict surrounding rock masses deformations.

Stability and reliability evaluation of tunnel and underground engineering is a very difficult problem in rock and soil engineering. Aiming at the problem of stability , reliability and safety of tunnel surrounding rocks and supporting system, the ultimate displacement situation of tunnel and underground engineering surrounding rocks is analyzed by stability analysis method of surrounding rock displacement discrimination; and a method of determining the ultimate displacement of tunnel and underground engineering surrounding rocks and an ultimate displacement analysis method of large strain of tunnel and underground engineering surrounding rock are put forward. Combining with an engineering example and in accordance with DGM（2，1）and Verhulst models, a displacement forecasting method of stability analysis of tunnel and underground engineering surrounding rocks is proposed. At same time, a displacement criterion of surrounding rock stability and reliability is established. The study can help to build the displacement forecast system to analyze the stability and reliability of tunnel and underground engineering surrounding rocks.

Most of the casing failure in salt bed are due to the nonuniform additional collapse load caused by salt creep. But there are still no any comprehensive strength design methods for casing under nonuniform load. Based on the full-scale casing strength test under nonuniform load, this paper analyzes the strength characteristics of the casing under nonuniform load and suggests that the equivalent failure load and the ratio of minor axis and major axis can be used to quantitatively describe the nonuniform load. The casing strength design charts presented by this paper can be used to check the safety of the casing in salt bed or help perform casing strength design when the load is known. The experiment results demonstrated that the strength of the casing under nonuniform load is 8 to 21 times lower than that under uniform load.

For the tunnel affected by first mining in Yangquan mining area, the thesis designed orthogonal experiments, analyzed the results with the method of numerical simulation and optimized the supporting parameters by the means of associated analysis of grey theory. The thesis selected the orthogonal experiments which needs 18 times numerical simulation including 8 factors with 3 levels each one. According to the results, the thesis researched the tunnel stabilization and deformation in the condition of different stress and supporting parameters. During the course of simulation, the thesis considered the strength effect about surrounding rock anchorage and gave the scheme about how the anchorage effect was executed in numerical simulation. On the other hand, the thesis expounded four kinds of evaluation criterions about tunnel stabilization and deformation to determine the corresponding local optimization scheme. On this base, the thesis comprehensively considered the factors of supporting cost and difficulty of construction, analyzed the results with the method of associated analysis of grey theory and got the optimal supporting scheme of primary dynamic pressure tunnel. This research results have been put into the use of primary dynamic pressure tunnel support in Yangquan mining area; and the support effect is satisfied.

Stability of mined-out area is maintained by improving the state of stress and restricting its displacement in surrounding rock with backfilling; and environment is also protected on the earth surface. Based on the mechanism of the backfilling, the influences of material factors on the backfilling are analyzed; and the optimal mixing proportion of materials is found with orthogonal experiment; and the characteristics of the backfilling with optimal mixing proportion are studied. The results show that the backfilling can restrict geostatic activity; protect environment ; and facilitate the reuse of resources of the mine.

Taking samples of silty clay existing distinctively in Wuhan District, a simulation experiment on true triaxial test, on which the stress path around foundation pit acts is carried out in order to obtain results of consolidated undrained test under plane strain condition. What’s more, this paper turns those results into the stress-strain curves, pore water pressure-vertical strain carves, and coefficient of intermediate principal stress-vertical strain carves, as well as a graph that describes stress path in the unloading test. The conclusions are drawn based on the above mentioned experimental results as follows: the condition that vertical pressure( ) remains constant and lateral unloading( ), the stress-strain curve would change from strain hardening to strain softening with the increase of consolidation pressure. Under lower consolidation pressure the curve shows dilatation, while under higher consolidation pressure shows an initial positive dilatation and then follows with dilatation; the intermediate principal stress( ) would slightly be superior to the minor principal stress( ). By means of defining the value of bd, the coefficient of intermediate principal stress shows stabilization. The deflection of effective stress path occurs with the increase of consolidation pressure. All these would lay a foundation for a further study on the effects of intermediate principal stress that caused to clay.

According to the characteristic of elastic waves propagation in medium and the application of elastic wave method in rock mass engineering, the paper has analyzed the characteristic of elastic waves propagation in cracked rock masses. It has put out the relationship of effective dynamic parameters of elasticity ( , , ) and crack density parameters, according to the principle of energy balance, rock rupture mechanics and Castiglano’s theorem, by looking the cracked mass with random cracks as quasi-isotropic cracked mass. On this basis, and through the theory of elastic wave propagation in isotropic medium, it has made out the relationship between the elastic wave velocity and crack density parameters. The theoretical research has shown that, in this kind of cracked rock masses, it will be nonlinear relationships between the effective dynamic parameters of elasticity and wave velocities and the crack density parameter; and with the increase of crack density parameter, the effective dynamic modulus of elasticity and the elastic wave velocities decrease; and at the same time, when the crack density parameter is very small, the effective dynamic modulus of elasticity and the elastic wave velocities change with the crack density parameter much more, which has explained the sensitivity of effective elastic parameters and elastic wave velocities to cracked rock masses.

Based on the rock characteristics of strain-softening and dilatancy, this paper developed a theoretical formula for calculating broken zone thickness of roadways, analyzed the influence of buried depth, rock strength, strain-softening extent, and support pressure on the surrounding rock stability of the deeply buried roadways. The new concept of ‘three bolting’ support is put forward, which refers to a supporting method combining bolt and shotcrete, grout, and anchorage cable. This new supporting method has been applied to engineering practice; and favorable technical and economic benefit is obtained.

Through the site measurement, the load transmitting phenomenon of thick sandy soil on the key roof stratum is found; and the concept of load transmitting factor of key roof stratum load layer is established. By simulating model test of dynamic load transmitting, the “arch type” and “thick arc shell” damage form of thick sandy soil layer upon shallow coal seam in first weighting is revealed. Finally, the formula of load transmitting factor during first weighting is set up. Those research and discovery will make progress on mined soil damage mechanism and dynamic roof structure theory.

The Hardin equation (1968) is usually adopted to calculate the elastic shear modulus Gmax of the saturated sand during earthquake in the dynamic effective stress analysis of soil structure. But the validity has not been confirmed because of the limitation of test facilities before. The effect of accumulated pore water pressure on Gmax is investigated based on a series of cyclic triaxial tests with piezoceramic bender element system. The test results indicate that the elastic shear modulus Gmax of fine sand can be calculated from the Hardin equation, but the material parameter must be determined by tests; and the elastic shear modulus decreases with the increase of pore water pressure and can also be calculated from the Hardin equation by adopting the actual average effective stress and void ratio during undrained cyclic loading.

By taking account of a building project in Chongqing, the authors adopt a structural analysis program 2D-σ to analyze evolvement regulation of the stress in the rock-mass related to a tunnel and a upper structure in four kinds of typical building step. The result indicates that interaction may exists between the tunnel and the upper structure; and the stress distribution come into being a break near the tunnel; and the tunnel side wall is compressed; and the tunnel arch is tensioned. The result will provide the references for the tunnel and the upper structure.

According to the purpose and characteristic of the weakening blast of hard top-coal in fully mechanized caving faces, that the dynamic breaking process of hard coal mass on blasting load is also a process to accumulate continuously damage is pointed out; and by the blasting dynamic deformation ratio experiment of the big coal samples, the power function of the deformation ratio attenuation corresponding to the blasting deformation wave peak of the hard top-coal weakening blast is proposed; and based on that with the rock blasting damage models of Tarlor and Drady etc., the distribution function of the macro-damage breakage degree of the top-coal weakening blast is derived; and the parameters and coefficients correlating the calculation are presented. It is the base to analyze and determine the rational parameters of the top-coal weakening blast.

The control of ground deformation in shield tunneling, as one of classical research problems on geoenvironmental and geotechnical engineering, is studied with the introduction of intelligent control method. A new theoretical model of intelligent control of ground deformation in construction under shield tunneling has been built. Fuzzy logic control, by adjusting the related shield construction parameters, has been used to realize the real-time and active control of deformation.

Several stable, continuous and thick incompetent beds exist in Jurassic red strata in Wanzhou. With the X-ray diffraction analysis, infrared ray analysis and scanning electron micrograph, the main mineral components and microstructures of the incompetent beds are identified. The results show that the incompetent beds are composed of montmorillonite, feldspar, ?-quartz, illite, chlorite, etc; and in which exist large amount of sheet crystals, many microfissures and micropores, a few microgrid fissures and directional crystal structures. Field investigations show that the incompetent beds were acted upon by a set of compressive tectonic forces, and shear failures occurred in some of the incompetent beds. A set of tests were conducted on the incompetent bed specimens to obtain the physico-mechanical characteristics. Test results show that the incompetent beds are medium swelling potential, and shear strength becomes very low once the incompetent beds attract water to saturation. The characteristics of the incompetent beds mentioned above prove that the incompetent beds become sliding surfaces of rock landslides easily under some special conditions.

In the construction process of Huayingshan highway tunnel, the geological circumstances are complex because of the main engineering geological problems met, such as karst, fault, sudden water inflow, coal and gas and so on. The successful experiences of cutting through coal seam in the right tunnel and the construction technology through the coal seam are summed up; these experiences can be used for safely cutting through coal seam in the big tunnel cross-section.

The working out area is a typical danger part in the highway tunnel. The rules and methods of treating with the working out area are summarized. The effect of working out area. on the tunnel stability is analyzed; and the treatment of the working out area is expounded with an example of the Xishanping tunnel.

Viscoplastic properties of clay were studied based on the test results of undisturbed and reconstituted specimens of three types of clays. To evaluate the viscoplastic properties, the strain rate was changed stepwise many times and creep tests were performed several times under otherwise monotonic loading on the different types of clay specimens. In addition, a nonlinear three-component model was proposed, which can simulate well the viscoplastic properties of clay.

The water stratum, distributing around the Tong-Yu Tunnel location, is eroded carbonate rock belong sea faces aggradations. A mud breakout was occurring at K21+780, with 940-meter depth of rock cover, in Feb 22th, 2004, in Tong-Yu Tunnel. According to the 3D-σsoftware analysis, the stress in the surrounding rock at K21+780 are proved, as well as the breakage region. Based on the conclusion of 3D-σsoftware analysis, combining with the engineering geology and construction technique, the forming reason of mud breakout in tunnel are discovered.

The triaxial creep experiments of a kind of claystone was performed with a specially designed triaxial creep testing device; and the effects of axial stress ?1 and confining pressure ?3 on the creep are investigated. It was found that for constant confining pressure, creep develops faster, the steady-state creep strain rate increases, and the life is reduced, with the increase of axial stress. If the stress difference ?? =?1–?3 is constant, creep strain and steady-state creep strain rate decrease and the life increases with the increase of confining pressure. The creep behavior of claystone was analyzed with an elastic-viscoplastic constitutive model for incorporating damage and its evolution. It is shown that the main features observed in experiments can be satisfactorily described.

Reservoir compaction and surface subsidence are a major concern in petroleum production. The significant influence of compaction and subsidence on oil field environments and petroleum production is reviewed. The mechanism of reservoir compaction is analyzed. And the methods for predicting and monitoring surface subsidence are discussed. Suggestions of taking the analysis of compaction and subsidence into consideration when planning the development of the oil field are put forward.

Some mechanical properties of granite residual soil were studied under special stress paths using advanced GDS stress path triaxial apparatus. The triaxial drained shear tests were conducted under two types of stress paths. The first set of tests was that mean stress p was constant while deviator stress q changed; the second set of tests was that q was constant while p changed. The test results show that the deviator stress-axial strain curve is hyperbola for the first set of tests; however, the mean stress-axial strain curve is power function for the second set of tests. The granite residual soil has shear shrinkage property. The rebound bulk modulus increases notably with deviator stress.

In order to inquire into the activities of roof rocks and its influence on tunnel support, two methods are used to analyze the failure forms of multilayer roof rocks of a tunnel which is buried in depth of 700 m. One method is considering the roof rocks which are in the fields from above 112 m to surface as the uniformly distributed loads; and another method is to analyze the all roof rocks from tunnel roof to surface. The simulating results show that: the results of compression , displacement and shear stress which are calculated by the first method are identical with them calculated by the second method. It is showed that the roof rocks separate from each other at the certain height to tunnel center, and two or more hard rocks and soft rocks composite the combined strata. The stress of tunnel support comes from the first combined strata mainly; and we define this height as the key support stress circle. The heights of the key support stress circle calculated with theory and simulation is about 75 m, and the error is 5.2 %.

The experiment conducted on MTS815 Rock Testing Machine recorded the whole-process curve of sandrock stress-strain under different confining pressures and investigated the four different phases on the curve as compacting, elastic behavior, strain hardening(plasticity) and strain softening(abruption). It analyzed at the same time the distortion character at each individual phase and the effect on rock hardness subjected to confining pressure. Then, according to this distortion character of rock, a single rock constitutive model based on Duncan Model is developed which is capable to describe rock compacting, elastic behavior and abruption. The improved model is used to illustrate the mechanism of rock distortion and abruption. It has been tested in experiment that the improved constitutive relation can do better in describing rock distortion and abruption.

The principle, method and techniques for measuring initial stresses in rock, by the Kaiser effect are described. And the crustal stress denotation of the underearth rock measuring point and the basic equation are derived; through making samples on 9 special directions on the beamed rock cores and doing acoustic emission experiment, the unilateral plus stress values on each direction are obtained. They are introduced into the crustal stress calculating formula, and then the values, azimuth angle and obliquity of the three principal stresses are obtained. The results of this experiment are capable of reference for engineering project.

As geologic condition is complex, it is unavoidable to encounter with some geologic hazards such as karst water gushing, rockburst, surrounding rock high deformation or collapse, prediction and forecast technique as the further realization and supplement of tunnel prospect is important to subtract and prevent hazard. The thesis cites Bijiashan Tunnel, as geologic term is complicated in the tunnel, various advanced prediction and forecast methods, which include engineering geology and geophysics technique , geology observation and analysis and equipment test, are used to forecast the geologic information in tunnel facing frontage; the forecast results are successful and guide the tunnel construction safety effectively.

In the process of the preloading, the foundation stability is calculated from one stage of filling height to next stage of filling height. According to the foundation stability the filling height and the loading time of the next stage could be given out. According to the results of Biot’s consolidation theory in each filling height, the foundation stability is calculated with the total stress method considering the strength increase and the effective stress method considering the over-static water pressure. Then an useful result is that the foundation stability factors calculated by the two methods are approximate equality.

High in-situ stress with some geological disasters induced, such as rockburst and large deformation, is an serious engineering problem always happened in tunnel construction, however, in-situ stress measurement is an important factor for the forecast of rock burst and other geological disasters; a test method using Kaiser effect of rock is being used widely at present. In the paper, the initial geo-stress field was researched by the method of Kaiser effect measurement; the numerical value and oriention of in-situ stress was gotten, and those results proved that the stress state of the tunnel is stable; the in-situ stress was being at a low lever. then this results was used in the criterion for rock burst and some thoerotical analysis, the conclusion that rock burst will not appear was taken. Finally, through numerical simulation by 2D-σ software, the conclusion upwards was also validated. In a conclusion,the poly-method of rockburst forecast is prior to other single method in veracity and reliability, and is valuable in the theory and engineering application of rockburst forecast.

In this paper, based on project excavation of the Wansongling tunnel, the monitoring way and controlling technology of vibration of blasting earthquake wave induced by tunnel excavation were studied. Via regression analysis for the results of monitoring on blasting vibration, the mathematical model of spread of blasting vibration induced by tunnel excavation was established; the orderliness of spread of blasting vibration was drawn. Combined the project, the empirical formula after revised of attenuation of blasting earthquake wave was put forward; Through contrasting and analyzing, the particle vibration velocity were forecasted by the orderliness formula of attenuation of blasting earthquake wave is precise relatively. At the same time, combined the excavation blasting construction of this tunnel project, the controlling technology measures of blasting vibration were put forward from the choice of the reasonable blasting time difference, the maximum charge quantity, the millisecond blasting, the excavation plan, springing blasting, so as to control the vibration velocity of ground within safety range in the process of this tunnel excavation construction, consequently the safety of ground buildings of construction segment and blasting work of this tunnel project was insured. This study will play an important role in guiding the excavation blasting construction of the tunnel project and assuring the safety of ground buildings.

This paper studies the coupling of engineering geology 3-D visualization with numerical simulation applied to some hydro- junction. The regular-grid stratified geological model is established through DEM techniques; and then based on bore data, and the boundaries of geometrical bodies under a series of working condition are mapped to the grids of the model. And the geological model is subdivided by a series of cross-sections under the condition that the topologies of two cross-sections are same (or one is degeneration of the other) if they are neighbors. After the cross-sections are obtained, the primitive meshes provided by FLAC3D are formed by adjusting and linking the grid points of two neighbor sections. By the method, numerical simulation of the hydro-junction engineering are carried into effect.

The engineering geological drilling exploration is carried out in the Mijiangou tailings dam area to serve the heightening design of enlarging its volume. According to the permeability parameters of the three zones, the tailing sand, the weathered rock mass and the rockfill of initial dam, determined by the inverse analysis based on the drilling exploration results and the heightening design plan, the seepage field in the heightened dam area is analyzed to get its distribution. The applied numerical method is the finite element one and the software is 3D-Seepage-Stress developed by the authors. It can be concluded that both the seepage free surface and the overflow point are very high under the heightening design plan, which is not profitable for dam stability and management. Also, the measures of drain pipes in the design of enlarging the volume are proposed.

Via nonlinear dynamic FEM, using Hoffman failure criterion, some models of high pressure water jet cutting rock are built; and the process of high pressure water jet breaking rock is researched. The conclusion, which the process of rock broken under high pressure water jet is divided into hammer impacting break and erosional break, is proofed by test to be true. There are two critical pressure of breaking rock which distinguish the hammer impacting break and erosional break; and the mechanism of hammer impacting break is different from erosional break; there is a broken area of tension stress while jet hammer impacting rock. Through analyzing, increasing jet impacting velocity, broadening jet’s diameter, speeding horizontal moving, adding the number of jet bundle and choosing a proper angle between 35 degrees and 40 degrees can enhance the efficiency of water shoot cracking rock.

By means of numerical simulation software ANSYS, deformation failure regularity of bolt-grouting support and bolt support for deep soft roadway is simulated. The stress, displacement and plastic zone of bolt-grouting support and bolt support for deep soft roadway is systematically analyzed. The research results indicate that the strength and bearing capacity of surrounding rock for bolt-grouting roadway is greatly increased. So the deformation of deep soft roadway is effectively controlled.

During loading process, deformation of rock will come into an unstable stage if the load is above a critical value. That is, the failure will evolve continuously under constant load. An ‘avalanche’ phenomenon appears in the failure process of rock. Based on SOC theory and BTW model, the damage evolvement and crack propagation rate are studied on instability and failure of rock. This presents a new approach to research the mesoscope evolvement law of rock failure.

Jointed segmental concrete lining is the main bearing component of the shield-driven tunnel; its structural properties directly affect the safety of tunnel. So it is very important to understand the realistic structure behavior for the reasonably designing shield-driven tunnel lining. The load distribution on the tunnel lining during construction is significantly different from that during normal using. This paper uses the FEM program which can propose contact problems to simulate the bearing properties of the continue, sequence and stagger concrete lining during construction stage, to gain their stress and deformation rules which will provide useful reference for the design of shield-driven tunnel lining.

The authors set up reasonable hydraulic model ,which simulates the change of the seepage field and stress field within the slope when the water level is up to 175 m. The seepage model of block-fracture slope is studied. In order to make the model more reasonable and more effective in application, the authors create the seepage model of double porosity media including discrete media and equivalent continuum. Based on the relationship of fracture and engineering mass, 1-2 grade fractal net is considered. According to the equivalent of pressure of two kinds of media, three-dimensional hydraulic model is created using modern fractal theory and its FEM solution is given.

The technique of the3D finite element method(FEM) of coupling saturated-unsaturated seepage, temperature and stress is studied; and the corresponding program for the FEM is developed. The following two hypotheses are used to simplify the system. The infection that the temperature works on the stress is considered while the infection that the stress and the seepage work on the temperature is not considered. The infection that the seepage works on the stress is considered while the infection that the stress and the temperature work on the seepage is not considered. The program is validated by comparing its simulation results and the result of elasticity mechanics.

Referring to industry criterion of choosing mechanics parameters, the rock mechanics parameters database system was developed by collecting plenty of rock mechanics parameters data, using data preprocessing, statistic analyses, grey system theory, artificial neural networks, experience analyses, etc. According to the rock name, efflorescent degree, condition of being saturated and so on, the rock mechanics parameters of actual projects may be queried, forecasted, judged, and decided by the system. The function, characteristic, collecting area of data, database construction, framework for this system are introduced in detail. Finally, a project example is described to introduce the usage of the system.