Research On Radial Grouting Construction Technology For Water-rich Tunnel

During the construction of the tunnel,various environments will inevitably be encountered.When the tunnel passes through the water-rich section,the interaction between water and surrounding rocks is reflected in the influence of water on the physical and mechanical effects of the surrounding rocks on the construction and operation of the tunnel.Safety is also reflected in the groundwater disturbance caused by the excavation of the tunnel,which changes the groundwater environment in the construction area.If the protection is not emphasized,it will have an inestimable impact on the local environment.This article takes the newly built Zhengpantai Tunnel of the Chongli Railway as the engineering background,and mainly researches from the following aspects:(1)Based on the drainage construction conditions of the water-rich tunnel,the stability of the surrounding rock of the water-rich tunnel,and the impact of the tunnel drainage volume on the regional water environment,first determine the standard of water inrush for the tunnel construction.(2)Under the condition of certain objective conditions,radial grouting is the most effective method for rapid construction and water stopping.By establishing a threedimensional model of the Zhengpantai tunnel,the optimization of radial grouting parameters is explored,mainly by establishing grouting circle models with different thicknesses and different permeability coefficients,and by conducting pore water pressure,water gushing,and surrounding rock stability.By comparison,reasonable radial grouting parameters that meet the construction allowable water gushing standard are obtained.(3)After the optimization of the radial grouting parameters,demonstrate the stability of the surrounding rock of the tunnel and the construction safety,and achieve the safety of the radial grouting construction of the tunnel when passing through the water-rich section.(4)Further study the impact of the tunnel on the groundwater environment.By using Geo Studio software to establish the steady state and transient models of the tunnel under various working conditions,the impact of tunnel excavation and radial grouting is analyzed from the changes in water pressure,gushing volume,and groundwater level,and the impact of tunnel drainage Radius,and finally simulate the groundwater level restoration process to study the groundwater level restoration conditions.