Study On The Anti-permeability Performance Of Mud Replacement Section In Freezing Hole For Freeze Sinking

In recent years,in the process of excavating vertical shaft of coal mine in the wester nareas,freezing method has been widely used to pass through soft water-bearing rock layers.In the process of shaft sinking with freezing method,the freezing hole which often passes though chamber becomesvertical water-conducting after the frozen wall thaws and threatens the safety of the mine.Mud replacement method forms the concrete loop in the annular space to seal up the vertical water-conducting,but there are still freezing holes which appear infiltration of water after using Mud replacement method.Expect for the fail of proper construction,the mud replacement section with poor sealing up performance may degrade from freezing and could be one reason of the infiltration.Adopting laboratory test,theoretical analysis,and model test research methods,this article carries out the research on expensive type retarder,and anti-penetrability about mud replacement section after freezing.And the concl usions of the researchmay guide the selection of materials and design of length.At first,based on laboratory test,the working performance of the retarder spiked with UEA,HEA,AEA has been researched.By free swelling rate test,the swelling rate of different adulterate amount was obtained,and the swelling rate test proved the effective ness of the expending agents.By expansion stress test,the relation between expansion and time was gained.By stone rate test,the stone rate of three different type of expensive type retarder was obtained.Secondly,though laboratory test,the anti-permeability of concrete loop and both boundaries before and after freezing was obtained.The comparison among three different types of mix proportion was made.Thirdly,by technical analysis,based on reasonable assumptions,the distribution law of osmotic pressure between seepage velocities in both boundaries was obtained.At last,on the basis of theory analysis and laboratory test,the comparison between original retarder and the expansive type of retarder was made.Three different groups of simulation test were carried out.The distribution law of osmotic pressure and seepage velocities of two boundaries in both types of simulations was obtained.And the qualitative index of both boundaries’ anti-penetrability was obtained.