On the one hand, fractal is character of damage mechanics and fractal dimension can fully be used to describe macro-behaviors in strata in mine. On the other hand, fractal dimension is the measurement of periodical pressure of working face in mine. Based on the study of damage and fractal dimension of periodical pressure in roof rock-mass at working face, new methods to predict periodical pressure are applied. Meanwhile, the relationship between damage and fractal is obtained, which it is important to guide safety in mining activities at working face.

On the basis of test results of micro-fracturing process and evolution of micro-cracks of rock in uniaxial compression, the theory of bifurcation, chaos and self organization in the nonlinear dynamics are applied in this research. The results show that, the evolution of micro-cracks could be described by the Logistic equation, so that the evolution of micro-cracks of rock has the characteristics of bifurcation and chaos. Meanwhile, the relationship between length and number of micro-cracks at each stress level has been studied. The results show that the process and evolution of micro-cracks are satisfied with power law, the system of micro-cracks in rock has the feature of self organization.

Anti-slide pile is a major landslide prevention measure.This paper analyzes the transition process of force between soil and anti-slide pile based on force equilibrium.According to the relationship of acting force and reacting force between soil and anti-shde pile,the stress distribution in the soil behind anti-slide pile is obtained.From the stress isograms,it is shown that the mechanism of soil arc between anti-slide pile and soil is the result of the stress state from imbalance to balance in soil.

With the constant expansion of scale and the increased depth in exploiting open-pit mine, the slope engineering is also heightened. Slope stability affects the safety of mine production and mine safety and stability of surrounding buildings. In allusion to increasingly prominent importance of stability analysis of the open-pit slope and in combination with practice of open-pit mining slope engineering at Manaoke diggings, the strength reduction method and the FLAC numerical simulation software are used to analyze the open-pit slope stability.

Justification for stick-slip instability to account for the fault-slip rockburst is presented and a model of spring-and-two-slider is introduced to simulate the behavior of stick slip for investigation into the nonlinear dynamical features that rockbursts exhibit. It is shown that fault-slip rockbursts could be satisfactorily explained by stick-slip motion, the chaotic behavior of which implies the mechanisms of rockburst are possibly deterministic instead of stochastic.

Monitoring and measuring of new Austrian tunnelling method(NATM) was conducted with a Leica TCA2003 Total Station and an XP99 Cymometer in a shallowly-buried long-span tunnel.The deformation and movement of country rock in tunnel were obtained to guide tunnel construction.Based on the country rock deformation,the optimum time for primary and permanent support was applied.Optimum timing successfully can avert accidents in construction and enhance construction quality.Numerical simulation indicates that tunnel excavation may have great influence on surrounding rock stability.It is important to reinforce monitoring to relevant locations during the construction process,to have timely feedback to guide construction,to adopt corresponding shoring measures,and to ensure construction safety.

This present paper adapts the theory of bifurcation, chaos, fractal geometry and self-organization in modem non-linear science to study the typical dynamic phenomena occurring in the process of exploitation activities in mines, analyses the non-linear mechanism of those phenomena and points out the non-linear dynamic behavior of the exploitation system. The results are of positive significance to controlling mine disasters and guiding exploitation.

Based on the CT real-time testing of coal microscopic damage propagation, the comparison of damage variable between CT scanning and Bellonoi equation, Lemaitre equation in the process of uniaxial damage spread was obtained which solves successfully damage discriminating 'scale' problem, and the results is more reasonable than Bellonoi equation and Lemaitre equation. In order to describe logically its behaviors and evolution, its constitutive model and evolvement function under uniaxial compression were carried through separately in pre-linearity phase, start and development. phase, speedup phase, which it is important to guide engineering.

Inappropriate methods of mining could lead to adverse concentration of stresses around roadways or working faces, thus possibly posing a potential threat to the safe operation of a colliery. The research work is devoted to investigating the redistribution of ground stresses in strata overlying steeply inclined coal seams worked by means of two different methods of mining, i.e. the straight longwall advancing and the oblique longwall advancing at Yanshitai Colliery, Chongqing Municipality, China. Where two mining methods were employed, stresses of ground supports for roadways and working faces were measured, respectively, indirectly reflecting the redistribution of ground stresses in overlying upper strata. Data indicate that the straight longwall working had a larger scope around roadways or working surfaces affected than the method of oblique longwall mining; in addition, field observations show that the oblique mining method has local falls after a longer face advance than the straight longwall working, both suggest that the oblique mining method is preferable in extracting steeply inclined coal seams dominating Southwest China coalfields, and has a more reliable control on the movement of overlying strata. Finally, the conclusion has been further supported by data obtained from laboratory tests of analog simulation.

High Density Resistivity Method(HDRM) is an effective tool for landslide survey,and the suitable in-situ working scheme and its data analyzing model are the base to obtain believable results.An innovative data interpretation procedure for locating slide-face position in complex geological conditions is proposed.The apparent resistivity patterns of different types of landslide are different even if the landslide is investigated with the same electrical array.The ration parameter method can improve the capability of two dimensional apparent resistivity section to reflect the distribution of the object inside landslide.Some landslide disasters along expressway are briefly introduced.The geometry parameters and the interspace characters of the landslide are obtained.Researches are made on the occurrence mechanism and deformation characteristics of landslide according to disaster characteristics.The landslide stability and its effect on the expressway under application are appraised,and the reliability of reinforcement work is evaluated.The principles for preventing and mitigating the landslide disaster of this type are put forward.

A uniaxial compression test on coal and rock was conducted with CT scanning to monitor the damage process of coal and rock in real-time. A mathematical model has been established to analyze the experimental results on the basis of modern nonlinear theories of bifurcation and chaos. The results show that the CT values and stress can be described by Logistic equation. The process of coal and rock damage has the characteristics of bifurcation and chaos.

Xiangjiashan landslide located nearby a freeway.This paper analyzes the reasons of formation of landslides on the basis of integrated analysis of the existing geologic explorations data,and meanwhile,evaluate the stability of landslide by means of back analysis method and limit equilibrium method which under the considering sliding mass and prior period anti-slope project as soil-pile complex.Finally,according to the characteristic of expressway landslide,both temporary protecting and perpetual comprehensive control scheme are made,it achieved good effect and could be used for reference in similar problems.

Through field survey and categorization, the defects in highway tunnel were analyzed under the consideration of reconnaissance,design and construction of the tunnel and referring to the stress distribution and loading of the tunnel. According to the run of leaks, they may be classified as vertical leak, sloping leak and cycling leak. The main causation of leaks came from construction, design and geological factors. Having understood the geological conditions, it was found that the measures to cure these defects were to strictly control the quality during construction. The causation and countermeasures found in study would be referable in controlling similar defects.

Because of the difficulties of experimental equipments and techniques, the experiment of rock under tension is more complex than that under compression. In some conditions, rock failure in situ begins with tension. In order to test the limit tensile strain of rock, the relationship between stress and strain, and the mechanical characteristics of rock, the methods for determining the stress-strain curves of rock specimens under tension are introduced, and the tensile stress-strain curves are analyzed. Meanwhile, the mechanical properties by direct tensile test are also compared with those by split method.

It is important that monitor measuring was applied in tunnel in regard to NATM. In this paper, the monitor measuring of NATM was studied in one tunnel in express. Based on the regularity and conditions of the surrounding rock deformation of monitor measuring in site, the Grey model is successful used to forecast the tunnel deformation. The optimum time for primary and permanent supports are obtained which averting successfully accidents in construction, which indicated that the forecast results are in good accord with monitor data. This measure insured to enhance the construction qualities and guide to Highway tunnel construction in Karst areas.

Rockburst is provided with the representative slip characters and the two state variable model could simulate the characters very well. On the study of the dynamics behavior of rockburst system, according to mechanics conditions and geological circumstances of rockburst, the two state variable model is introduced to describe the dynamics behavior and evolvement behavior of rockburst. The research shows that the parameters k and β greatly affected the dynamics behavior and evolvement behavior of rockburst; and? , f contributed much to the model also. This model well simulated the stick-slip character relative to single state variable model. And the two state variable model truly describes the process of failure of rockburst system which explains the mechanism of rockburst and provides the theoretical foundation to forecast rockburst.

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.

Based on the careful investigation in site of highway tunnel,the classification of tunnel disease is obtained.According to the reconnaissance,design and construction of tunnel,in relation to the distribution of stress and loading of tunnel by numerical analysis and back analysis,the existing condition and reasons of tunnel diseases are carefully analyzed.At the same time,the disease management methods are provided,which are important to guide similar tunnel to search diseases reasons and manage diseases.

针对重庆市南桐矿物局砚石台煤矿的生产技术条件和开采地质条件,考虑到传统方法预测冲击地压的局限性,将BP人工神经网络和遗传算法相结合,开发了冲击地压预测软件BPAGA Tools.实际工程事例表明,该软件预测速度快,预测精度高,适用性强,在生产应用中取得了较好的预测效果,为冲击地压的预测提供了新途径,对冲击地压的防治具有重要意义.

Using the CT machine,the real-time computerized tomography testing of coal under the uniaxial compression was completed.Through CT scanning,the clear CT images which included the step from the micro-crack closure to the micro-crack growth,bifurcation,development,failure and the post-failure step were obtained.According to the CT values,the meso-damage evolution of coal under uniaxial compression was analyzed.Based on the results which tallied with micro-facture,cavity growth,and section forming obtained from CT scanning of coal,the study on the damage propagation of coal was carried out.It is demonstrated that in the process of unloading,the failure of coal is paroxysmal.Based on the change of the CT values and CT images obtained from scanning test,the propagation law of the meso-damage in coal is deduced.The change law of crack width and length related to creeping time has been quantitatively analyzed.In the light of the law and CT images,the macro-damage process of coal under uniaxial compression in Baijiao Mine has been divided into 5 steps;the damage-weakening step,the linear step,the step when the damage starts to evolve and damage develops steadily,the step when the damage development speeds up and the weakening step after reaching peak.We think it is important to study the production and evolution of micro-cracks.