Experimental Research On Mortar Bolt Anchoring Body Corrosion Regularity Of Ammonium Sulfate Environment

With the uncoiling of several opinion of the state council,the engineering construction in the South part of Jiangxi province will usher in great development.It is the major ionic rare earth producing area and the civil construction within mining area has become inevitable trend.Sulfur ammonium leaching agent used in the in-situ leaching ore fluid is a sort of very strong corrosive matter.Its concentration can have a significant impact and durability on cement base material structures in the mining area.Considering the environmental problems led by ammonium sulfate during the rare earth exploitation,we need to further study the corrosive rules,mechanism and control of the solid mortar anchor.In this paper,in combination with the science and technology project of Jiangxi provincial bureau“Study on the Durability of Cement Base structure in the Highway Engineering of Earth Mining Area after In-situ Leaching”?NO.2014C0007?,and the mechanism and control of the corrosion of cement soil in the ionic rare earth mining area of Jiangxi Province Natural Science Foundation Project"?NO.20151BAB206054?To take the whole highway as the background,we have conducted laboratory research on the solid mortar anchor.The major contents of the research are as follows:?1?By adopting the immersion test in laboratory and simulating the corrosive environment of engineering,the ammonium sulfate solution was configured and its anchorage mortar effect on physical and mechanism properties was researched under the different concentrations of solution different kinds of cements,and different ages of corrosion as well as different additives.Probing the chemical corrosion mechanism of the sulfate ammonium environment,the dissolution and decomposition caused by the corrosion of NH₄⁺ion and the crystallization and pressurization caused by the corrosion of SO₄^2-ion can be obtained.At the same time,by using the grey correlation analyze the numerous factions that affect the compressive strength of mortal anchor.The compressive strength in the anchoring of the GM?1,1?prediction model was also constructed.?2?Through the indoor experiment,conducting researches respectively on ammonium sulfate corrosion after anchorage mortar-anchor interface and mortar anchor-matrix interface between bonding properties,testing the bond slip changing curve on two kinds of interface on the condition of different water cement ratio,age of corrosion and concentration of ammonium sulfate;By observing the appearance and test data analysis,studying the anchorage mortar of the kinds of ultimate strength of the interface and bond slip stiffness change rules in the ammonium sulfate corrosive environment.?3?Through the observation about the shape,the test about ultimately comprehensive strength and the analysis about the variation of quality loss of the specimen,solid mortar anchor,corroded by?NH₄?₂SO₄ with a concentration of 5%,it has been studied that the single and double mineral admixture has a effect on the chemical degraded property that the solution of?NH₄?₂SO₄ corrodes solid mortar anchor.Meanwhile,by utilizing the mechanism of resisting to corrosion under the effect of?NH₄?₂SO₄ as well as the grey correlation method,the analysis about the influence of comprehensive strength that admixture affects solid mortar anchor follows.And also,the conclusion has been drawn that the effect on resisting corrosion improves to be optimal as solid mortar anchor is mixed up with a single 50%mineral slag,20%fly ash and a double 20%fly ash,40%mineral slag as well.Simultaneously,by analyzing the appearance of all sorts of specimens'microstructure from the admixture by means of the SEM,it could be obviously discovered that various admixtures present their own microstructure changing rules.