TYPHOON WIND DISASTER ASSESSMENT BASED ON SPATIAL CHARACTERISTICS

In view of the problem that the wind disaster assessment method considers only the intensity-related single factor and cannot accurately characterize the degree of typhoon wind disaster, this paper studies the importance of typhoon spatial characteristics to disaster assessment by assessing wind disaster based on area integral according to the wind disaster index corresponding to three different wind resistance levels of coastal infrastructures. Grid resolution affects wind disaster assessment index, i.e., the finer the grid-scale, the higher the index; the sea surface temperature (SST) is also an effect factor of the index, and the higher the SST, the higher the index; the typhoon wind disaster can be accurately characterized when the resolution is about 200 m or even 500 m. The results show that the area integral method can more accurately characterize the typhoon wind disaster than the traditional single factor assessment method. However, the small wind speed in the outer region has a great impact on the wind disaster. As the highest proportion of SST-27 to SST-29 is up to 65%, SST-26 is up to 90%. Therefore, for typhoon wind disasters with small wind speed - large size and large wind speed - small size, the impact of small wind speed on wind disaster assessment is significantly reduced after the introduction of the concept of cut-in wind speed. The highest proportion of SST-27 to SST-29 is 13%, the highest proportion of SST-26 is 3%. The problem, that small wind speed has large proportion range but no effect on structural damage, is solved.