Assessment and analysis of collapsing houses by aerial images in the Wenchuan earthquake
汶川地震房屋倒塌的遥感监测与分析

Information of houses collapsed by the earthquake is one of the important indicators to assess the earthquake damage intensity, and support the emergency decision-making process in rescue and recovery operations. We monitored the house collapse ratio and its spatial variation in the 5.12 Wenchuan earthquake by airborne images, and analyzed its spatial variation relationship with the earthquake intensity, geological structure, stratum lithology and surface rupture caused by the earthquake. The house collapse ratio was derived by visually interpreting ADS40 airborne images acquired from May 15 to May 28, 2008. The results show that the houses were widely damaged in the earthquake-damaged region, especially in Wenchuan County, Mianzhu City, Shifang City, and Pengzhou City and Wenchuan County which experienced the severest damage. We analyzed the spatial variation of the house collapse ratio and its relationship with earthquake intensity, geological structure, stratum lithology and surface rupture caused by earthquake. The results demonstrate that the house collapse ratio and the earthquake intensity have positive relationship, and the ratio of house collapse is controlled by the geological structure, stratum lithology, and building structure too. The house collapse ratios, which are above 50%, mainly distributed along the surface rupture in a SW to NE direction.