Seismic design of liquid-containing concrete structures
thesisposted on 08.06.2021, 08:13 by Au Lu
The seismic design of structures is a requirement for any places [sic] where earthquake [sic] occurs, and the design is based upon the codes that vary according to the jurisdictions in which the code was developed for. This study introduces and assesses the document ACI 350.3-06 which was developed by the ACI Committee to guide the design of liquid containing structures, and compares to other codes such as ACI 350.3-01 and NZS 3106 of New Zealand Standard. The importance of liquid containing structures cannot be stressed further, as it is apparent in nuclear applications. The failure of tanks could be due to many reasons: 1) Shell buckling, caused by axial compression due to overall bending. 2) Roof damage as a result of sloshing of the upper portion of the containing liquid due to insufficient provision of freeboard. 3) Failure of inlets and outlets due to their inability to accommodate the deformations of the flexible tank. 4) Differential settlement or failure of supporting soil. The pressures resulted from earthquake [sic] can cause catastrophic disaster, and they [sic] are the impulsive and convective mode which exerts pressures on the walls of the tank. The hydrodynamic model used to estimate these pressures in the ACI 350.3-06 document has also adopted earlier works from Housner, Veletsos, and Shivakumar. Throughout the years, the code has transformed tremendously, and this study shows that the codes are very similar in many ways, yet their differences can yield significantly different results. Furthermore, the results from the various codes are illustrated using the same example, and the validity of the results are determined as well. The effects on seismic design due to the types of structure, whether the tank is rigid or flexible, and the support system are also introduced; moreover, their absences and the variations in the estimation of seismic parameters in some codes are also shown to have a large effect on the load estimation.