地震孤岛现象对交通生命线工程抗震的思考与建议

Reflections and Suggestions on Aseismicity of Transport Lifeline Project based onEarthquake Isolated Island Phenomenon

地震后最怕某地区陷入"孤岛"状态,致使灾区与外界联系的交通线完全中断,救援人员和物资不能在灾后黄金救援时间内抵达"孤岛"地区,救援工作延误导致的人员伤亡数量急剧增加。近年来地震"孤岛"现象发生频率之高,损失之惨重,不仅显示出生命线工程的重要性,而且也暴露出目前关于生命线工程抗震设计领域存在的问题。通过对历次地震"孤岛"现象和抗震设计规范进行剖析,提出在进行生命线工程结构抗震设计时不能单纯考虑结构自身的重要性及灾后修复的难易程度,还需引入生命线重要性修正系数,以提高灾后交通生命线工程应急救援的可靠性,避免灾后"孤岛"现象的再次发生。

The most terrible condition after an earthquake is some areas are isolated as a lonely island where traffic lines to outside is completely broken off which lead to aid workers and supplies cannot reach there in the golden time of rescue, as a result the number of casualties will be sharply increased. The high occurrence frequency and the heavy loss of ＂isolated island＂ after earthquakes in recent years does not only show the importance of lifeline projects but also expose some problems in the seismic design of lifeline projects. Through analysis of the ＂isolated island＂ phenomena and the code for seismic design, it puts forward that not only should the importance and the degree of difficulties to recovery of structures after disaster be considered but also the modified coefficients of importance be introduced into the design of lifeline engineering, so that the reliability of emergency rescue of traffic lifeline can be improved and the phenomenon of ＂isolated island＂ can be avoided.