| Water leakage is an inevitable problem in the development,use and maintenance of underground projects such as tunnels.Among them,the slow seepage problem of concrete lining structure in underground space is easy to be ignored.Seepage is a common problem in tunnel(laneway)engineering and a difficult problem in governance.In this thesis,based on the discussion of the causes and mechanism of the formation of the roof and floor of the concrete lining tunnel(laneway),based on the principle of electroosmosis technology,the micro mechanism of electroosmosis technology to control the water control of the tunnel(laneway)is studied,and the electroosmosis water control model and equation are established,and the model test and industrial test are carried out.The details are as follows:(1)The main reasons for the formation of slow seepage are the head pressure on the roof and floor of concrete lined tunnel(laneway),the combined water,and the existence of concrete pores and micro-cracks.The mechanism is as follows: In general,the volume of water molecules is smaller than that of concrete pores.Combined with the action of water head pressure and weak electric field force of microscopic bound water,water molecules are transferred from the water-bearing rock mass to the open face of tunnel with zero hydraulic gradient,and the infiltration phenomenon occurs.(2)Based on the principle of diffuse infiltration,combined with electroosmosis technology,a DC electric field can be applied to the surrounding of the tunnel lining.On the one hand,the current of the electric field is used to migrate the seepage water to the rock and soil outside the lining to keep the concrete structure dry.On the other hand,the potential energy of the electric field is used to resist the water potential energy in the rock and soil,and the water in the rock and soil is controlled at the electroosmosis cathode position,so as to achieve the purpose of concrete water control.The electroosmosis water control effect is divided into three stages: free water control stage,pore water control stage and bound water control stage.(3)The theoretical model of slow seepage electroosmosis water control in tunnel(laneway)is established.Based on the theory of groundwater seepage(Darcy ’s law)and the theoretical model of electroosmosis(double electric layer theory,electroosmosis consolidation theory,HS electroosmosis model hypothesis),the theoretical model of electroosmosis water control suitable for the slow seepage disease of tunnel lining structure is established,and the seepage rate control equation of electroosmosis water control is obtained.The equation shows that for different head pressure and permeability coefficient,the seepage rate of slow seepage can be controlled by changing the intensity of DC electric field to achieve the purpose of waterproof.(4)On the basis of theoretical research,the physical model test of tunnel(laneway)was carried out: the electroosmosis waterproofing effect under different factors was studied,and the water seepage amount,water content change,water content distribution,potential,current intensity and sample resistance in the process of electroosmosis waterproofing under different electric field strength,water head height and permeability coefficient were obtained.The orthogonal test was carried out.The test results show that the factors affecting the electroosmosis waterproof time are power supply voltage,water head height and permeability coefficient from large to small.(5)Based on the above research results,the industrial test research was carried out in the water seepage project of No.1 auxiliary inclined shaft in Liangshuijing Coal Mine.According to the specific diseases and actual leakage conditions,a comprehensive treatment scheme of ’dynamic grouting + electroosmosis water control ’ was proposed.After 2 months of construction,the tunnel is basically in a dry state and the effect is good.The thesis contains 73 figures,24 tables,and 96 references. |
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