1996 Vol. 4, No. 3

论文
An integrated study on the change of hydro-environmental system, the types and mechanism of rock-water interaction in reservoir areas is described in this paper. Based on the above-mentioned study, the geoenvironmental change and occurrence of environmental hazards are discussed. An approach to the geoenvironment assessment and geohazard prediction is suggested as well in the paper. An integrated study on the change of hydro-environmental system, the types and mechanism of rock-water interaction in reservoir areas is described in this paper. Based on the above-mentioned study, the geoenvironmental change and occurrence of environmental hazards are discussed. An approach to the geoenvironment assessment and geohazard prediction is suggested as well in the paper.
Some major problems urgent be solved in environment engineering geology are put forward, are superficial geodynamic conditions in western China and their environment effects, assessment, prediction and mitigation of hazardous landslides and falls, and evaluation, forcasting and controlling of disastrous geological processes in long deeplying underground tunnels. Based on brief analysis of the present research status of these problems, the main scientific points and the relveant research countermeasures are discussed. Finally, a basic research technical clue to of them are suggested. Some major problems urgent be solved in environment engineering geology are put forward, are superficial geodynamic conditions in western China and their environment effects, assessment, prediction and mitigation of hazardous landslides and falls, and evaluation, forcasting and controlling of disastrous geological processes in long deeplying underground tunnels. Based on brief analysis of the present research status of these problems, the main scientific points and the relveant research countermeasures are discussed. Finally, a basic research technical clue to of them are suggested.
The problems on the duality and coherence of natural hazards, formation of anthroposphere, and preservation of ecological environment are discussed from a viewpoint of environmental system of human living as an entirety in the paper. It is suggested that the natural hazards in short time scale and small extent can be considered as a catastrophe, but in long time scale and large extent they may be a self-regulation and self balance process. There exists a bidirectional effect relation between natural hazards and human society. The coherence of natural hazards (swarm and association of their occurrence)depends on their homology, chain occurrence, and rhythm. The anthroposphere is a product of the new evolutional stage of the Earth. It is characterized by deep level,high intensity, wide activity extent, and regulation performed with information feedback. The formation of the ideas mentioned above will be of great importance in hazard study, in decrease of hazardous losses, and in breaking a new sustainable development path. The problems on the duality and coherence of natural hazards, formation of anthroposphere, and preservation of ecological environment are discussed from a viewpoint of environmental system of human living as an entirety in the paper. It is suggested that the natural hazards in short time scale and small extent can be considered as a catastrophe, but in long time scale and large extent they may be a self-regulation and self balance process. There exists a bidirectional effect relation between natural hazards and human society. The coherence of natural hazards (swarm and association of their occurrence)depends on their homology, chain occurrence, and rhythm. The anthroposphere is a product of the new evolutional stage of the Earth. It is characterized by deep level,high intensity, wide activity extent, and regulation performed with information feedback. The formation of the ideas mentioned above will be of great importance in hazard study, in decrease of hazardous losses, and in breaking a new sustainable development path.
After a brief discription of geological structure of China coastal zone, the authors suggest that the geodynamic system since the Cenozonic Era fundamentally determinedthe different paterns from the south to the north in the coastal geological environment and disasters in eastern China. More over, the general features of engineering geological environment in the coastal area and the problems concerned during engineering construction are expounded in the paper. A primary assessment of future tendency of geological environment and disasters in the coastal area, especially in three deltaes regions, i. e.Yellow River, Yangtze River and Zhujiang River deltaes, is made on the basis analysisof global sea level changes as well as those in China coastal zone over the past 100 years,the regulavities of crust morement, and the impact of human engineering activities on geological environment in the coastal zone of river mouths. Therefore, it is evident that the environment and the sustainbale development in China coastal areas, espacially in the Bobal Rim in the 21st Century will face to severe challenges. According to the distribution of natural resources and geological-geographical environment features, and the needs for sustainable development strategy in the future, several countermeasures and suggestions are set forth. After a brief discription of geological structure of China coastal zone, the authors suggest that the geodynamic system since the Cenozonic Era fundamentally determinedthe different paterns from the south to the north in the coastal geological environment and disasters in eastern China. More over, the general features of engineering geological environment in the coastal area and the problems concerned during engineering construction are expounded in the paper. A primary assessment of future tendency of geological environment and disasters in the coastal area, especially in three deltaes regions, i. e.Yellow River, Yangtze River and Zhujiang River deltaes, is made on the basis analysisof global sea level changes as well as those in China coastal zone over the past 100 years,the regulavities of crust morement, and the impact of human engineering activities on geological environment in the coastal zone of river mouths. Therefore, it is evident that the environment and the sustainbale development in China coastal areas, espacially in the Bobal Rim in the 21st Century will face to severe challenges. According to the distribution of natural resources and geological-geographical environment features, and the needs for sustainable development strategy in the future, several countermeasures and suggestions are set forth.
The coastal hydrogeological environment is a main environment in which saline intrusion easily occurs. For investigation of the environment a combined method of macroscopic system analysis and microscopic contradictory factors analysis was used.Saline intusion disaster in Guangrao County resulted from vulnerability of the natural environment and deterioration of the social-economical environment of the studied area. The essence of the whole process of saline intrusion lies in the destruction and reconstruction of the balance between the motive force and the resistance of saline intrusion. The basic contradictions causing environment deterioration in the area of saline intrusion.the are analyzed and the scheme for hydrogeological environment regulation as an effective measure for saline intrusion disaster prevention is worked out. The coastal hydrogeological environment is a main environment in which saline intrusion easily occurs. For investigation of the environment a combined method of macroscopic system analysis and microscopic contradictory factors analysis was used.Saline intusion disaster in Guangrao County resulted from vulnerability of the natural environment and deterioration of the social-economical environment of the studied area. The essence of the whole process of saline intrusion lies in the destruction and reconstruction of the balance between the motive force and the resistance of saline intrusion. The basic contradictions causing environment deterioration in the area of saline intrusion.the are analyzed and the scheme for hydrogeological environment regulation as an effective measure for saline intrusion disaster prevention is worked out.
South China Sea is one of the significant marine development areas in China. It is very important to evaluate scientifically the marine engineering geological conditions on the basis of research on various factors for geologic hazards. The potential factors for geologic hazards are the essential causes of geologic hazards. They not only affect the process of marine oil exploration and development, but also cause a lot of unexpected economic loss in submarine engineering operations. This paper studies the types, size distribution, formation process, and inducing factors for possible geolgic hazards, on the basis of practical surveys in South China Sea more than 20 years. The practical measures for preventing geologic hazards are suggested in order to provide a foundation for the development of sea resources. South China Sea is one of the significant marine development areas in China. It is very important to evaluate scientifically the marine engineering geological conditions on the basis of research on various factors for geologic hazards. The potential factors for geologic hazards are the essential causes of geologic hazards. They not only affect the process of marine oil exploration and development, but also cause a lot of unexpected economic loss in submarine engineering operations. This paper studies the types, size distribution, formation process, and inducing factors for possible geolgic hazards, on the basis of practical surveys in South China Sea more than 20 years. The practical measures for preventing geologic hazards are suggested in order to provide a foundation for the development of sea resources.
By analysis of test data on stress and seepage in rock mass, a fractal geometry formula for relation between stress and seepage is presented in the paper. According to the formula of relation between stress and seepage, a generalized double porosity media model for coupled seepage and stress field in fractured rock mass system is set up. The model is based on rock mass structure in the study area) which is considered as generalized double porosity media. It is shown that the model is satisfied with practice application to seepage and its control in some hydroelectric engineering projects and stability evalution of high slope rock. By analysis of test data on stress and seepage in rock mass, a fractal geometry formula for relation between stress and seepage is presented in the paper. According to the formula of relation between stress and seepage, a generalized double porosity media model for coupled seepage and stress field in fractured rock mass system is set up. The model is based on rock mass structure in the study area) which is considered as generalized double porosity media. It is shown that the model is satisfied with practice application to seepage and its control in some hydroelectric engineering projects and stability evalution of high slope rock.
Fault movement has a complex and variable pattern and one segment of a great faultzone is usually a unit of rupture. In order to meet the needs for major engineering projects and strong earthquake predication, It is necessary to lacate which segment of a fault zone is active. We propose in this paper that the movement of middle segment of Xiangshan-Tianjingshan fault zone is mainly stick-slip and both its eastern and western segments show mainly stable-slip. On the basis of microstructural characteristics of fault gouge and the segment geometry. Fault movement has a complex and variable pattern and one segment of a great faultzone is usually a unit of rupture. In order to meet the needs for major engineering projects and strong earthquake predication, It is necessary to lacate which segment of a fault zone is active. We propose in this paper that the movement of middle segment of Xiangshan-Tianjingshan fault zone is mainly stick-slip and both its eastern and western segments show mainly stable-slip. On the basis of microstructural characteristics of fault gouge and the segment geometry.
After the water stotage of the reservoir, underground stress field, strain field and flow field are formed in a certain spatial range. A mathematical-mechanical model is set up to describe the characteristics of hydraulic pressure stress field. By applying the NOLM83 two-dimensional finite-element program for non-linear stress-strain and stability static force analysis of elastic-plastic rock-soil system, we find that the maximum principal stress of the reservoirs hydraulic pressure stress field decreases gradually from the center of the reservoir to its both sides and from the surface to the depth. The stress, strain, and the range of the Shuitianba fault affected by future hydraulic pressure stress at the reservoir are further studied. The result shows that the affected range in plane is about 5~6 km at the both sides of the fault. Due to the floating effect of rock mass, the cumulative displacement of the surface is less than 10 mm and decreases downwards. Therefore, the fault can fully withstand the hydraulic pressure stress induced by the water storage of the reservoir, and will not affect the safety of the ThreeGorges project since no moderate-strong reservoir-induced earthquake will occur. After the water stotage of the reservoir, underground stress field, strain field and flow field are formed in a certain spatial range. A mathematical-mechanical model is set up to describe the characteristics of hydraulic pressure stress field. By applying the NOLM83 two-dimensional finite-element program for non-linear stress-strain and stability static force analysis of elastic-plastic rock-soil system, we find that the maximum principal stress of the reservoirs hydraulic pressure stress field decreases gradually from the center of the reservoir to its both sides and from the surface to the depth. The stress, strain, and the range of the Shuitianba fault affected by future hydraulic pressure stress at the reservoir are further studied. The result shows that the affected range in plane is about 5~6 km at the both sides of the fault. Due to the floating effect of rock mass, the cumulative displacement of the surface is less than 10 mm and decreases downwards. Therefore, the fault can fully withstand the hydraulic pressure stress induced by the water storage of the reservoir, and will not affect the safety of the ThreeGorges project since no moderate-strong reservoir-induced earthquake will occur.
Using grey system theory, periodic weighting in coal mine face is regarded as a catastrophe. Following building mechanism of linear GM (1, 1) forecasting model, a non-linear GM(1,1) forecasting model in constructed in this paper. Usinga special case of non-linear model, the Verhulst model and linear model, the periodic weighting lengths under two different coal mine conditions are forecasted. The results show that for different geological conditions, different forecasting models may be used and no a single linear model can simply forecast. For situation of geological conditions approriat to a sudden change occurring, excitative forecasting model can be constructed to forecast periodic weighting length and other pressure parameters. Using grey system theory, periodic weighting in coal mine face is regarded as a catastrophe. Following building mechanism of linear GM (1, 1) forecasting model, a non-linear GM(1,1) forecasting model in constructed in this paper. Usinga special case of non-linear model, the Verhulst model and linear model, the periodic weighting lengths under two different coal mine conditions are forecasted. The results show that for different geological conditions, different forecasting models may be used and no a single linear model can simply forecast. For situation of geological conditions approriat to a sudden change occurring, excitative forecasting model can be constructed to forecast periodic weighting length and other pressure parameters.
Deformation-failure regularity of loess and force distrubition regularity in lining of large-span deep buried loess tunnel under the other constant conditions along the whole profile during typical step excavation are studied. After revealing their excavation effects, the authors indicate the difference between these regularities are caused by the different excavation pattern, and anlyze the rational force distrubition regularity. Deformation-failure regularity of loess and force distrubition regularity in lining of large-span deep buried loess tunnel under the other constant conditions along the whole profile during typical step excavation are studied. After revealing their excavation effects, the authors indicate the difference between these regularities are caused by the different excavation pattern, and anlyze the rational force distrubition regularity.
The morphological feathers of rock structural faces with different roughness and undulation are studied quantitatively by theoretical analysis and numerical simulation in this paper. An emphasis is made on the relationship of the morphological parameters of structural faces and the characteristic parameters of principal morphology. Their sampling effects is also studied. A series of results obtained has a great significance to choose rationally the morphological parameters of surface when the interrelation between the morphological parameters of surface and physical quantities is set up, and provides a basis for the choice of rational sampling interval and minimum sampling length. The morphological feathers of rock structural faces with different roughness and undulation are studied quantitatively by theoretical analysis and numerical simulation in this paper. An emphasis is made on the relationship of the morphological parameters of structural faces and the characteristic parameters of principal morphology. Their sampling effects is also studied. A series of results obtained has a great significance to choose rationally the morphological parameters of surface when the interrelation between the morphological parameters of surface and physical quantities is set up, and provides a basis for the choice of rational sampling interval and minimum sampling length.
This paper deals with basic characteristics of incompetent rocks. According to experiment results of the expansibility and slaking durability, frost-thawing action, and mechanical properties of the weak rocks, the effect of time and environment (water content, temperature, stress in the earths curst) of the rock occurrence on the mechanical properties of the weak rocks are analysed. The variation regularities of the mechanical properties of different rock elements are summarized. The author propose the principle for determining strength of weak rocks. This paper deals with basic characteristics of incompetent rocks. According to experiment results of the expansibility and slaking durability, frost-thawing action, and mechanical properties of the weak rocks, the effect of time and environment (water content, temperature, stress in the earths curst) of the rock occurrence on the mechanical properties of the weak rocks are analysed. The variation regularities of the mechanical properties of different rock elements are summarized. The author propose the principle for determining strength of weak rocks.
Technical problems are put forward concerning construction of a telemetric seismic network in Xiaolangdi Reservoir area. The major problems concerning the design are analyzed.Then some opinions are suggested. They will be instructive to the planning and construction of the seimic network. Technical problems are put forward concerning construction of a telemetric seismic network in Xiaolangdi Reservoir area. The major problems concerning the design are analyzed.Then some opinions are suggested. They will be instructive to the planning and construction of the seimic network.