Numerical Simulation Study On Stability Of Bedded Salt Rock Gas Storage

The salt rock is an international-recognized ideal medium for energy storageand it is in the good graces of many countries．The researches about undergroundsalt gas storage in our country indicate that the feature of salt rock mass is multiplethin-layer and including many fine interlayer．Building or reconstructing salt cavityfor energy storage in this bedded salt，it is inevitably affected by interlayer whetherduring building with water solution or operation．So in this paper，based on a seriesof mechanical experiment test researches of bedded salt by pervious，the influenceof interlayer to salt cavern storage stability is investigated in detail from someaspects by numerical simulation．The main content as follows：1．According to widespread research methods of salt cavern storage stability，focusing on two-point namely the constitutive model establishing method of saltrock and evaluation criteria of cavern stability，make a systematic summarization．2．The interlayer mechanical characteristics (namely soft interlayer and hardsandwich) to long-term stability of salt gas storage under many working casesincluding different interlayer thickness and different operation pressure iscontrastively discussed，and a detail analysis of cavern shrinkage，surrounding rockmass plastic zone and maximum displacement vector distribution is given．3．For the beneficial effect of hard anhydrite interlayer to cavern deformation，the influences of cavern height radius ratios，operation pressure and interlayernumbers to＂reinforcement＂ role of hard anhydrite interlayer is investigated．4．The variation law of interlaminar interface shear stress during gas storagesegment in bedded salt in considering of rock creep is investigated．And the shearslipping situation between cavern roof salt and roof hard anhydrite interlayer is alsodiscussed under two different cavern height radius ratios．5． The stability of underground gas storage after excavation and underlong-term cycle pressure operation is simulated in the engineering background of1-18salt group at Yunying salt mine in Hubei province and discussed the range ofreasonable operation pressure.