Non-uniform Characteristics And Analysis Method Of Groundwater Inflow Into Underground Oil Storage Caverns

Underground oil storage caverns is controlled by the flow of groundwater in the rock mass,so it is very important to study the characteristics of groundwater in surrounding rock.The water inflow is the important property parameter of the surrounding rock of the oil depot.It is of great value to understand the basic performance of the surrounding rock of the oil storage caverns and to develop the standard of the grouting and the optimization of the running mode.As a kind of geological material,there are irregular fracture s in the rock mass,and its seepage characteristics are affected by the geometrical and mechanical properties of the fracture.Based on the background of an underground crude oil storage caverns,The nonuniformity of water inflow and analysis method are analyzed by using geological survey,field monitoring,theoretical analysis and numerical simulation,The influence of the geometrical and mechanical properties of fracture on the water distribution characteristics is systematically analyzed and a series of research results are obtained:(1)The parameters of an underground crude oil storage caverns are obtained by field data.The H-H formula is used to obtain the length of trace and the distribution of trace length are analyzed by software.The REV size determination method under the condition of the radiation flow is presented.The REV size and the equivalent permeability coefficient under the radiation and parallel flow conditions are compared and analyzed,and the non-uniform relationship between the geometrical characteristics of the fracture and the water inflow characteristics is analyzed.(2)The expression of inflow in circular caverns of fractured rock mass under simple conditions is deduced.The influence of stress field on the apertures of fracture and water inflow is obtained,and the stress field under normal stress condition is obtained induced non-uniform distribution of inflow in caverns.(3)The water inflow analysis of circular caverns in fractured rock mass under complex conditions is carried out.Based on the theory of fluid-solid coupling of discrete media,the influence of stress field,fracture mechanics and geometry on the size and distribution of water inflow are studied.The non-uniform distribution characteristics of water inflow caused by the stress field,the dilatancy effect and the structural surface are obtained under the conditions of normal and shear stress adjustment..The empirical formula of inflow in the fractured rock mass under complex conditions is put forward.