2994

2846

كارشناسي ارشد

مهندسي زلزله

اصفهان: دانشگاه صنعتي اصفهان، دانشكده عمران

1384

ده، 127، [II]ص.: مصور، جدول، نمودار

محمد مهدي سعادت پور

فرهاد بهنام فر

حميد هاشم الحسيني، مهرزاد طباطبائيان

1395/12/16

كتابنامه

عمران

مهندسي عمران

ID2846

به فارسي و انگليسي:قابل رويت در نسخه ديجيتالي

Abstract One of the important points in design of structures is considering the random lateral loads like earthquakes In order to provide the seismic resistance of houses in different design methods the storey drifts and accelerations must be lessened as much as possible The only practical way to reduce them simultaneously is the application of SeismicIsolation concept in the base of structures Isolation systems should have two capabilitiesof flexibility and energy dissipation at the same time But sometimes the energy dissipaterpart can not control the large displacements of base in strong ground motions Therefore a gap between the base of isolated buildings apd their surroundings retaining walls entrybridges adjacent structures must be considered to allow the base displacement Intheory if the gap size is designed according to extreme earthquakes the building willnever bump in to the obstacles but when the impact happens dynamic response ofbuildings will remarkably change Reviewing the researches on this matter brings aquestion and that is either the high degree of isolation approach and at the same time limiting the base movement with stops or reduction of seismic isolation degree lesseningthe efficiency of isolation to control the base displacement In this study the question willbe answered and the effect of different isolators gap size stop stiffness and number ofstories on dynamic response of buildings when bumping in to stops will be investigated For modeling the isolated structures the nonlinear SAP2000 software containing theNllink elements for simulating every nonlinearity in structures has been used The studiesconcentrate on response of one storey and five storey buildings mounting on 3 differentisolation systems laminated rubber bearing lead rubber bearing resilient friction baseisolator In first step with altering the isolation degree the maximum displacement of freebase is determined Then in case of isolated building surrounded by stops thesuperstruchlre is supposed to be in both elastic and inelastic range For an estimation of theamount of energy dissipated by different factors in isolators also the amount of energydissipated by damping and inelastic deformations of superstructure the earthquake inducedenergy and the dissipated energy by different sources with respect to time for 3 cases ofisolation in two condition of flexible and rigid stops have been determined Finally theobtained results show in those cases that for reduction of induced forces to the structure the base isolation method is being used and even for much more decrease in forces higherdegrees of isolation can be used the possibility of large displacements in base andconsequently the possibility of bumping into surrounding obstacles and developing largeforces in the structure in absence of necessary gap is a significant factor that can influence selecting the seismic isolation degree v aIJJli I I j

محمد مهدي سعادت پور

فرهاد بهنام فر

حميد هاشم الحسيني، مهرزاد طباطبائيان