設備等非結構構件於建物中之耐震分析公式探討

A Seismic Design Formula for Equipment and Non-Structural Compments in Building Structures

盧煉元(Lyan-Ywan Lu) ； 洪俊宏(Jiun-Hung Hung) ； 薛嘉傑(Chia-Chiea Hsu)

《結構工程》 29卷3期 (2014/09) Pp. 59-80

https://doi.org/10.6849/SE.201409_29(3).0004

摘要

設備之耐震性為建物耐震工程中極重要的一環，因為重要設備若於地震中損壞將直接影響建物之使用功能，並造成經濟損失。而由於結構動態放大效應之故，設備之地震力需求與建物極為不同，應特別加以考量。現行耐震設計規範中有關設備之耐震分析與設計，係以非結構構材最小地震力公式加以規定。然而該公式並未考量建物及設備本身之動態特性，故易造成過於保守或低估設備地震力之情形。有鑑於此，本文乃利用反應譜及振態疊加原理重新推導建物中設備之地震力公式。在給定設計反應譜及建物與設備之動態參數（振頻及阻尼）條件下，該建議公式可推估設備在建物中不同樓層之最大地震力或最大加速度需求。惟該公式不適用於設備與建物發生共振之情況。為驗證公式之精確性，本文在數值案例中分別模擬一低頻（柔性）設備與一高頻（剛性）設備置於中低建物中之最大地震反應。經與歷時分析比較結果顯示，只要不是在共振區內，不論是低頻或高頻設備，本文公式所推估之樓層設備最大加速度反應皆遠較規範公式精準，且非常接近歷時分析之結果。其對於低頻設備之地震加速度反應推估尤其精準，此亦顯示本文建議公式極適用於具柔性之低頻設備，例如：隔震設備，細長塔架設備或管線設備等。

關鍵字

非結構構件 ； 耐震設計 ； 設備耐震 ； 設備地震力 ； 設備加速度 ； 設備隔震 ； 柔性設備

並列摘要

In a building structure, the seismic capacity of equipment is an important issue, since it may cause serious functionality and financial losses of the building if the equipment is damaged in an earthquake. Due to the dynamic amplification effect of the underlying structure, the seismic demand of the equipment is very different from that of the primary structure and has to be treated with special attention. In current design codes, the seismic force of equipment is usually estimated by using the formula of the minimum seismic demand for nonstructural components. However, in this formula, the dynamic properties of the primary structure and equipment are not considered; therefore, the seismic force of the equipment may be over- or underestimated. To this end, based on modal superposition and response spectrum methods, a design formula is derived in this study. When the fundamental frequency and damping ratio of the primary structure and equipment are specified, the derived formula is able to estimate the seismic force or acceleration of equipment located on a certain floor level. Nevertheless, the formula is not applicable to the case in which the frequency of equipment is close to the resonance frequency of the structure. The accuracy of the formula is verified by using the data obtained from time history analysis of equipment placed on mid-and low-raised buildings. The simulation result demonstrates that the maximum accelerations of either soft or rigid equipment predicted by the proposed formula are far more accurate than the values predicted by the design code and are very close to the ones obtained from the time history analysis, particularly for low-frequency equipment. This indicates that the formula is particularly suitable for low-frequency equipment, such as base-isolated, slender or pipeline-type equipment.

並列關鍵字

Nonstructural component ； seismic design ； seismic load ； equipment protection ； equipment isolation ； acceleration response