Research On The Corrosion Damage Mechanism Of The Auxiliary Shaft Lining Of Luohe Iron Mine

The wellbore is the "throat" of the mine.It is an important project for the mine personnel and materials to enter into the mine and the information communication between the well and the well.Wellbore safety plays a decisive role in the production safety of the whole mine.After long term use,shaft lining concrete will suffer structural deterioration due to various reasons.This phenomenon will not only affect productivity,but also threaten mine safety.Through the initial investigation,the damage occurred in Anhui Maanshan Ironand Steel Group Luohe iron mine auxiliary shaft wall multiple,concrete,exposed steel bars and drop,water spray phenomenon.According to the characteristics ofauxiliary shaft wall damage,based on the understanding of regional geological and hydrogeological conditions,through the indoor simulation experiment reveals the failure mechanism of concrete corrosion,and puts forward the corresponding corrosion protection measures.The main research results are as follows:(1)Use the Piper three line graph and clustering analysis,the brick bridge group shaft fracture confined water pouring water,underground water and surface water and water known mine analogy analysis,results show that the water and the surface water of mine shaft from the brick bridge group confined aquifer,and the mining field of confined water and brick water table group no hydraulic connection bridge..(2)Through the design of indoor immersion test,it is found that the concentration of magnesium ion and sulfate ion in the soaking solution of the undisturbed concrete decreases with the increase of immersion time,which indicates that the seepage of the shaft and the surface water of the mining area all cause corrosion to the undisturbed concrete.In contrast,the resistance to sulfate concrete is good,but the durability of magnesium salt corrosion is poor.(3)The correlation between ions based on analysis that consists of two sets of soaking liquid concrete in the wellbore undisturbed,correlation between chloride ion and sulfate ion were-0.959.-0.842,indicating the presence of chloride ions to sulfate corrosion inhibited,and in the two experiments,the correlation with magnesium chloride ion and calcium ion were-0.936,-0.932,-0.868 and-0.429.that did not generate chlorine salts to produce expansive destruction of concrete in chloride.(4)Using regression analysis,it was found that the four values of the room temperature had no effect on the pH value of the solution,and the regression coefficients between them were 0.3951,0.3461,0.3104 and 0.4879,respectively.At the same time,the regression coefficients between magnesium ion and sulfate ionwere 0.2661 and 0.0099.respectively,in two groups of experiments,which indicated that the strong corrosive sulfate MgS04 did not corrode the concrete in these twogroups.