汶川地震人员死亡率及经济易损性探讨

Exploration of mortality and economy vulnerability of Wenchuan earthquake

由于高震级、高烈度地震的发生在某一区域是小样本事件,基于区域历史震例的震害预测方法对强震损失的快速评估结果具有很大的局限性;因此探讨利用时效性高的孤立强震震例进行震后的快速评估分析具有重要的现实意义。系统整理了汶川地震的震害资料,以烈度区和行政区划为分类单元建立了汶川地震损失数据库。利用震区内130个县、市的震害数据,选用USGS PAGER系统中的人员死亡率与地震烈度的函数模型计算得到了区域适用的人员死亡率。利用汶川地震的经济损失记录,建立了极灾区、严重灾区、重灾区和受灾区的经济损失比,在此基础上,利用历史震例对人员死亡率及经济损失比的有效性进行了验证。结果表明,模型及相应的损失率能够较好地估计川滇地区强震可能造成的人员死亡及经济损失。

Earthquake loss assessment methods based on the case statistics of the regional low-intensity earthquakes have limitations due to the scarcity of high-magnitude, high-intensity earthquakes in a specific region. Thus, the loss assessment methods based on historical cases can not meet assessment requirements of the current socio-economic vulnerability. For this reason, exploring suitable methods which use the latest single case of strong earthquake to estimate the current seismic vulnerability of the region has practical significance. This paper compiles earthquake damage data systematically, establishes Wenchuan earthquake loss database using intensity and administrative divisions as classification rule. Using the earthquake disaster data in 130 counties/cities and the empirical mortality model in USGS PAGER, we got regional applicable mortality. Besides,using the economic loss records, this paper establishes the GDP-direct-economic losses-ratio for the extremely, severely, heavily destroyed areas and affected areas respectively. By comparing the actual losses of some earthquakes happening in Yunnan Province with the estimation using the mortality and GDP-direct-economic-losses ratio, we can find the effectiveness of these models in Sichuan ＆ Yunnan provinces.