醫院消防撒水系統耐震評估與易損性簡化分析方法研究

Abstract

近年來由於性能設計理念蓬勃發展，建築結構之耐震能力獲得提升，地震造成之主要災害以及經濟損失已從結構轉為非結構系統。 醫院非結構設備中之消防撒水系統於中小型地震中，若於某處發生漏水，或天花板經撒水頭碰撞發生粉塵掉落、擴孔等災情，甚至於大震中，撒水系統支撐處失去抗震能力，可能造成醫院中斷正常醫療機能，且無法阻止淹水、火災等二次災害。因此，消防撒水系統需要以性能設計法進行耐震評估，若耐震容量不足則必須進行補強。 為了評估國內醫院建築之消防撒水系統是否具備足夠耐震能力，本研究提出消防撒水系統耐震詳細評估(方法A)、局部詳細評估(方法B)以及適合工程師應用之簡化評估流程(方法C)。以案例醫院為例，針對消防管線系統耐震性能表現建立易損性曲線，並探討不同評估方式之結果與適用性。研究內容簡述如下: 1. 消防管線性能設計方法:本研究參考FEMA P58[1]性能設計概念，考量案例醫院結構在沒有發生倒塌，且可修復的前提下，進而探討結構物附屬之非結構系統(消防管線等設備物)易損性。 2. 本研究利用數值軟體MIDAS建立案例醫院結構數值模型而得非線性結構反應，探討管線易損性分析使用之輸入波特性影響以及地震強度增量規劃。 3. 案例醫院消防管線系統詳細分析:利用數值軟體SAP2000建立案例醫院頂樓處之消防撒水系統，並模擬管線與天花板或隔間牆之間、螺紋接頭以及吊桿之非線性行為，透過增量動力分析而得樓層消防管線系統易損性(方法A)。 4. 案例醫院消防管線系統局部詳細分析與簡化評估:將整層樓之消防撒水系統，簡化為最易受損病房單元增量動力分析(方法B) ，並依醫院消防管線系統特性，提出適合工程師手算評估之簡化評估方法(方法C)。比較不同方法求得之消防管線耐震能力結果，提出之簡化方法相較於詳細評估法更適用於一般工程師，預期更有效率獲得保守之評估結果。

Based on the popularization of performance design concepts for structures of critical building (e.g. hospitals and schools) in recent years, non-structural seismic damages (e.g. sprinkler piping systems) are more common than structural ones. Fire protection sprinkler systems plays important roles to prevent fire disasters and ensure occupant safety.However, failure of fire protection sprinkler system will result in not only threat to occupant safety but also the shut down of medical function and relating expense on repairing. Therefore, an accurate assessment method to evaluate the seismic ability of fire protection system is necessary. The common seismic failures resulted from fire protection sprinkler systems are impact damages of ceiling boards, leakages of 1″threaded joints and breaks of hangers. In order to understand the seismic ability of components mentioned above, this research propose several assessment methods and take NTU Hospital Yunlin branch as an example to conduct the fragility analysis of the component in fire protection sprinkler system. The main results are briefly described below: 1. Performance design method for piping systems: Referring to FEMA P58[1], only when building structures are judged as reparable will assessment of sprinkler piping be meaningful. Therefore, in this study, seismic performance of sprinkler piping will be evaluated only when the structure is reparable. 2. In order to investigate the effects of characteristics of input motion on the fragility analysis of piping systems, a nonlinear numerical model was established using MIDAS software for the RC structure of the example hospital building. 3. A detailed numerical model of the horizontal sprinkler piping system was established using SAP2000 software to simulate nonlinear behaviors of hangers and the nonlinear relationship between piping and ceiling systems or partition walls (Method A). The fragility parameters of three seismic performance of piping system were than obtained through incremental dynamic analyses. 4. According to the dynamic characteristics of the sprinkler piping system, a partial detailed analysis method (Method B) and a simplified assessment method (Method C) are proposed in this study. Comparing to the result of Method A, the one of Method B is more conservative but through a more efficient process. Method C is provided to be engineers an additional choice that a rapid but rough judgment in the seismic performances of sprinkler piping systems can be made based on in-situ observations and the floor response spectrum. The fragility results of Method C are very close to those of Method B in terms of median values but are with quite low divergence.