Study On Flow Dynamic Evolution Characteristics And Regional Water Inflow Prediction Method Of Tunnel Water Inrush

The water inrush always bursts accidentally, presses hugely, flows massively, and shows multiple types. This problem is world-class project difficulty. In the process of tunnel excavation, the original tunnel region hydrology geology environment is changed, and tunnel becomes a new good drainage channel. The sudden flood water hazards hinder the tunnel construction and delay the construction period. Therefore, dynamic evolution characteristics of sudden tunnel inrush and the instantaneous water inflow prediction flood must be researched to further control and govern the water disaster.The unity PDEs of Darcy flow and of the non Darcy flow are established as control equation of numerical simulation. The transient flow process of water inrush exposed fault fracture zone and exposed karst conduit are consided, flow dynamic evolution of the effects of time and space characteristics are analyzed. Combined with numerical analysis and water inflow prediction analytical formulas, dynamic water inflow change law is analyzed comprehensively, the tunnel regional water inflow prediction system is formed.First of all, the numerical models of water inrush exposed fault fracture zone and karst conduit are established. In order to study on flow dynamic evolution of tunnel water inrush and water inflow prediction, the influences of permeability coefficient, storage coefficient ratio, geological defect dip angle and geological defect width are analyzed.Secondly, when disaster water flowing into tunnel, water flow can be divided into the Darcy flow, Brinkman flow and Turbulent flow. Time effect and space characteristics of flow velocity and pressure are analyzed and dynamic evolution characteristics are revealed.Finally, in view of the field of engineering, the real regional water inrush models are established based on regional hydrogeology and engineering geology conditions. Numerical method and analytical method combined with model test are used to predict the regional field water inflow comprehensively, correspondingly to guide the management of tunnel water inrush aera.