بررسی رفتار ارتعاشی و پاسخ های لرزه ای مخازن مستطیلی ذخیره آب

Abstract:
The experimental study of structural vibration is often performed to determine the modal
parameters of a structure or to verify the theoretical models and predictions. The first phase of
this research involved the experimental determination of the modal properties of a rectangular
steel tank with different levels of water. The natural frequencies obtained from the
experiments were compared to those calculated by the analytical models.
In the second phase, a procedure for computing hydrodynamic pressures in rectangular tanks
is proposed. This procedure considers the effect of tank wall flexibility in determining the
hydrodynamic pressures produced by the impulsive response. Based on a two-dimensional
model of the tank wall, a dynamic time-history analysis was carried out. The results were
compared with other models based on the current design practice codes and standards, which
use a lumped mass approach. The comparison shows that, in most cases, the lumped mass
approach overestimates the base shear. The effect of wall flexibility on wall displacements
and base shears are also discussed.