DYNAMIC ANALYSIS OF HIGH-LEVEL WASTE STORAGE TANKS

DOE ''tank-farm'' sites consist of a large number of underground high- level waste storage tanks (HLWST). Seismic analysis and design of HLWS Ts requires proper evaluation of fluid-structure interaction and hydro dynamic pressure. Although simplified guidelines for such tanks are av ailable, a rigorous analysis invariably necessitates detailed finite e lement modeling. A systematic step-by-step approach for dynamic analys is of a HLWST using ADINA fluid elements is presented here. Initially, an open liquid-filled cylindrical ground-supported tank model is set up and frequency analysis studies for different tank configurations co nducted with displacement-based (D-fluid) and potential-based (P-fluid ) elements. The results are compared with the available data. The proc edure is then extended to analyze the response of the tank to El Centr o 1940 earthquake ground history and results verified for displacement s and hydrodynamic pressure. Although ADINA's P-fluid elements give mo re accurate frequencies and pressure distributions than D-fluid elemen ts, they cannot be at present used for seismic loading. The D-fluid el ements are shown to perform adequately for practical problems under co nsideration.