Study Of Harbin Metro Survey,pumping Test And Hydrogeology Parameter Calculation

In recent years,with the development of social economy,underground deep foundation pit projects such as subway and underground commercial streets have been developed rapidly.For the deep foundation pit engineering,in order to complete its safety and smoothly,efficiently,and precipitation is a must to avoid the phenomenon of foundation pit sand flow,piping and foundation pit collapse and other damage.Therefore,the foundation pit precipitation is also more and more attention by designers and workers.The permeability coefficient and influence radius of submerged aquifer are two important hydrogeological parameters in the design of foundation pit precipitation,which in turn directly influences the reliability of the design of foundation pit precipitation.Therefore,it is a key factor to study the permeability coefficient and influence radius of submerged aquifer.At present,most of the production practice is based on the steady flow pumping test formula to determine the permeability coefficient and radius of the submerged aquifer.However,such pumping tests generally require more exploration and test work than under any circumstances.By sorting and analyzing the data of pumping test,the following conclusions are obtained:(1)In pumping test,ZK01-ZK06 holes are fully penetrating well,permeability coefficient is relatively reliable from the perspective of hydrogeological parameters;ZK01-ZK06 holes are partially penetrated well,the hydrogeological parameters are calculated by the empirical formula,and the numerical values are in line with the actual parameters.(2)By comparing the topography and groundwater level with the water level of songhua river,it is determined that the flow of groundwater is basically perpendicular to the songhua river.At the hydraulic slope of 2 ‰,the infiltration velocity of the groundwater is 0.0493 m/d,and the actual average velocity of groundwater is 0.197 m/d.The underground water level of the river water level of songhua river will be replenished and the stabilization measures should be carried out.(3)The groundwater has a slight corrosive effect on the reinforced concrete structure of Harbin metro engineering,and the anti-corrosion measures should be taken.