Study on the comparation of building damage extracted from different RS images acquired after 2010 M=7.1 Yushu, Qinghai, China earthquake

The capability to identify damage level of building due to destructive earthquake from RS image depends on the sensor type (for example optical or SAR) and spatial resolution. It is usually estimated by considering the object size and the pixel size, the number of pixels the object covers. Such comparison does not show effective capability of damage grade identification. The authors have developed quantitative methods to determine earthquake damage grade by using a RS seismic damage index (RSDI) which describes the seismic damage level in an area scale of street block or village. RSDI differs from the seismic damage index determined through ground survey (GDI). The comparison between RSDI and GDI will suggest difference in damage identification. In this paper, the estimation of building damage grade is introduced based on the quantitatively extraction of building damage grade from various RS images acquired after 2010 Ms7.1 Yushu earthquake, Qinghai, China. Then a series of quantitative models between the RSDI and GDI for each source of RS image are obtained. The capability to identify building damage from RS image with different resolution will be analyzed in the paper.