柔性儲存槽之動力分析

Abstract

本文根據簡化之儲存槽模型，建立柔性儲存槽之運動方程式，進而分析柔性儲存槽之基本動力特性。數值模擬分析藉由不同之地震震波與強度，比較柔性與剛性儲存槽動力特性之差異，並進行一系列的參數研究。分析結果顯示，細長形柔性儲存槽由於槽壁的振動導致衝擊動態水壓增加，但隨著儲存水位降低其動態水壓之分佈則趨近剛性儲存槽之結果；矮胖形儲存槽動力行為近似剛性儲存槽，其動態水壓與剛性儲存槽之結果接近。此外，槽壁的振動與液面激盪位移之互制效應極微，故流體液面激盪位移可由剛性儲存槽估算之。

In this study, the equation of motion of flexible tanks under seismic load has been derived based on a simplified model, which allows for analyzing the dynamic characteristics of flexible tanks. A series of numerical simulations has been conducted to explore the difference of dynamic characteristics between flexible and rigid tanks via different earthquakes of various intensity levels. Simulation results indicate that the impulsive pressure for slender tanks increases due to the vibration of the tank shell, while the distribution of the dynamic pressure becomes closer to rigid tanks as the storage level lowered. The dynamic properties of broad tanks are similar to rigid tanks as reflected from the distribution of dynamic pressure. Moreover, the coupling effect of surface sloshing with the shell vibration is found negligible in the cases studied, which suggests the sloshing displacement may be estimated from the hydrodynamic analysis of rigid tanks.