Analiza dinamičkog sadejstva tla i objekta primenom metode konačnih elemenata

Abstract

Predmet ovoga rada je linearna analiza dinamičkog sadejstava tla i objekta pri zemljotresu, primenom metode konačnih elemenata (MKE). Za rešenje odgovora rotaclono-simetričnog sistema je korišćena metoda podstruktura. Dinamičke paramétré tla za krut kružni temeij fundiran ria tlu iznad osnovne stene smo odr edili primenom MKE. Tlo je idealizovano podelom na osno-simetriene konačne elemente uz primenu graničnih uslova po silama koje omogućavaju transmisiju seizmiòkih talasa iz zone temei ja u okolni slojevit, v iskoelast ičan poluprostor. Dobijena rešenja su uporedena sa teorijskim. U okviru toga, detaljno je analiziran problem odgovora sistema slojeva za talase u ravni, upravno na ravan i u ci 1indričnim koordinatama. Za sva tri slucaja je formulisana tzv. prenosna granica (transmitting boundary). Na mode lu zgrade nuklearnog reaktora prikazani su neki aspekti interakc i je tla i objekta primenom ekvivalentne metode i metode koncentrisanih masa.

A substructure method for earthquake analysis of soil-structure interaction is presented. The procedure is applied to the analysis of axisymmetr ic systems. Dynamic stiffness coefficients of rigid disk resting on layer built in at its base, are determinated by a finite element method. The transmitting boundary between the finite element "core" region and viscoelastic soil layers of infinite horizontal extent are superimposed. The core region is discretized by means of axisymetric finite element. A series of parametric studies of dynamic stiffness coefficients are presented. The substructure method is applied to simplified nuclear containment structural model founded on the "hard" and the "soft" layer. The interaction systems are analysed by equivalent method and lumped mass method.