Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An ...Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An evaluation method of the global stability coefficient of underground caverns based on static overload and dynamic overload was proposed.Firstly,the global failure criterion for caverns was defined based on its band connection of plastic-strain between multi-caverns.Then,overloading calculation of the boundary geostress and seismic intensity on the caverns model was carried out,and the critical unstable state of multi-caverns can be identified,if the plastic-strain band appeared between caverns during these overloading processes.Thus,the global stability coefficient for the multi-caverns under static loading and earthquake was obtained based on the corresponding overloading coefficient.Practical analysis for the Yingliangbao(YLB)hydraulic caverns indicated that this method can not only effectively obtain the global stability coefficient of caverns under static and dynamic earthquake conditions,but also identify the caverns’high-risk zone of local instability through localized plastic strain of surrounding rock.This study can provide some reference for the layout design and seismic optimization of underground cavern group.展开更多
On the basis of the relationship between each classification index for underground chambers and the elastic wave velocity of rock mass, a corresponding relationship between the classification of rock surrounding under...On the basis of the relationship between each classification index for underground chambers and the elastic wave velocity of rock mass, a corresponding relationship between the classification of rock surrounding underground chambers and the initial damage variable is established by using the wave velocity definition of the initial damage variable of rock masses. Calculation and analysis of relevant data from a hydropower dam located in Southwest China show that the initial damage variable obtained by means of surrounding rock classification has a close relationship with that calculated by wave velocity, which verifies the rationality of the relationship of the two classification indices. This study establishes a foundation for further damage mechanics and stability analysis on the basis of surrounding rock classification.展开更多
Based on the basic principle of the finite element method, the implicit composite element method for numerical simulation of seepage in underground engineering is proposed. In the simulation, the faults and drainage h...Based on the basic principle of the finite element method, the implicit composite element method for numerical simulation of seepage in underground engineering is proposed. In the simulation, the faults and drainage holes are set implicitly in the model elements without adding additional elements. Elements containing fault or drainage-hole data are termed composite elements. Then, their information data in model could be obtained. By determining the osmotic transmission matrix of the composite elements, the permeability coefficient matrix is then obtained. The method was applied to the numerical simulation of the seepage field around the underground powerhouse of the Ganhe Pumping Station in Yunnan, China, using a compiled three-dimensional finite element method calculation program. The rock mass around the site includes two faults. The seepage field in the rock mass was analyzed at different stages of the engineering project. The results show that, before the excavation of the underground caverns, the rock mass seepage is affected by the faults and the groundwater permeated down along the tangential fault plane. After the excavation of the caverns during the operation period, the groundwater is basically drained away and the underground caverns are mostly above the groundwater level. Thus, the calculation results of the engineering example verify the implicit composite method for the simulation of faults and drainage holes. This method can well meet the calculation demands of practical engineering.展开更多
基金Project(2023YFC2907204)supported by the National Key Research and Development Program of ChinaProject(52325905)supported by the National Natural Science Foundation of ChinaProject(DJ-HXGG-2023-16)supported by the Key Technology Research Projects of Power China。
文摘Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An evaluation method of the global stability coefficient of underground caverns based on static overload and dynamic overload was proposed.Firstly,the global failure criterion for caverns was defined based on its band connection of plastic-strain between multi-caverns.Then,overloading calculation of the boundary geostress and seismic intensity on the caverns model was carried out,and the critical unstable state of multi-caverns can be identified,if the plastic-strain band appeared between caverns during these overloading processes.Thus,the global stability coefficient for the multi-caverns under static loading and earthquake was obtained based on the corresponding overloading coefficient.Practical analysis for the Yingliangbao(YLB)hydraulic caverns indicated that this method can not only effectively obtain the global stability coefficient of caverns under static and dynamic earthquake conditions,but also identify the caverns’high-risk zone of local instability through localized plastic strain of surrounding rock.This study can provide some reference for the layout design and seismic optimization of underground cavern group.
文摘On the basis of the relationship between each classification index for underground chambers and the elastic wave velocity of rock mass, a corresponding relationship between the classification of rock surrounding underground chambers and the initial damage variable is established by using the wave velocity definition of the initial damage variable of rock masses. Calculation and analysis of relevant data from a hydropower dam located in Southwest China show that the initial damage variable obtained by means of surrounding rock classification has a close relationship with that calculated by wave velocity, which verifies the rationality of the relationship of the two classification indices. This study establishes a foundation for further damage mechanics and stability analysis on the basis of surrounding rock classification.
基金supported by the National Key Basic Research Program of China(Grant No.2015CB057904)the Major Program of the National Natural Science Foundation of China(Grant No.91215301)+1 种基金the National Natural Science Foundation of China(Grant Nos.51279136&51209164)the Research Fund for the Doctoral Program of Higher Education of China(Grant No.20130141110015)
文摘Based on the basic principle of the finite element method, the implicit composite element method for numerical simulation of seepage in underground engineering is proposed. In the simulation, the faults and drainage holes are set implicitly in the model elements without adding additional elements. Elements containing fault or drainage-hole data are termed composite elements. Then, their information data in model could be obtained. By determining the osmotic transmission matrix of the composite elements, the permeability coefficient matrix is then obtained. The method was applied to the numerical simulation of the seepage field around the underground powerhouse of the Ganhe Pumping Station in Yunnan, China, using a compiled three-dimensional finite element method calculation program. The rock mass around the site includes two faults. The seepage field in the rock mass was analyzed at different stages of the engineering project. The results show that, before the excavation of the underground caverns, the rock mass seepage is affected by the faults and the groundwater permeated down along the tangential fault plane. After the excavation of the caverns during the operation period, the groundwater is basically drained away and the underground caverns are mostly above the groundwater level. Thus, the calculation results of the engineering example verify the implicit composite method for the simulation of faults and drainage holes. This method can well meet the calculation demands of practical engineering.
