Liquefaction Hazard Map in Real Time

Abstract eng:
Recently, earthquake hazards have been more unpredictable and severe. Thus many countries have tried to make a special seismic defense system including domestic liquefaction hazard maps. Several countries drew the liquefaction hazard map for metropolitan area under the specific acceleration. Korea also has tries to establish the earthquake and tsunami defense system based on the GIS for several years but there are some troubles to set up and verify a reasonable system because there was few earthquake hazard data in Korea. Nevertheless, Korea kept going to set up and upgrade National Disaster Prevention System. It was thought that liquefaction and land sliding hazard maps were necessary to make the earthquake prevention effectively. In Korea, a domestic liquefaction assessment can obtain reliable prediction results for seismic design of facilities along with the site response analysis function in case of site amplification. This method is good for a seismic design of a new facility. However, it will take much time in building a national defense system to deal with a lot of data. Thus, it is proper to apply the site amplification coefficients in the macro liquefaction hazard mapping instead of site response analysis. In this study, we have carried out the liquefaction potential assessment using geotechnical information of 110,000 boreholes in Korea. In the assessment, we determined soil type using average shear wave velocity and we carried out the simplified liquefaction potential assessment using site amplification coefficients. In special, we developed an Excel spreadsheet to calculate the liquefaction potential index automatically. The Excel spreadsheet includes soil classification, the simplified liquefaction assessment, and calculation liquefaction potential index at a position of GIS map. Also, we calculated liquefaction potential indexes using the developed Excel spreadsheet and liquefaction hazard maps against desirable earthquakes with maximum accelerations ranged from 0.06g to 0.38g were drawn. Also, to develop the real time hazard map, we investigated the relationship between liquefaction potential indexes and accelerations at every point on the map. In the GIS map, we used 2Km by 2Km cell unit for possible to connect with NEDP in Korea. For its verification, Hongsung Earthquake, Odae Mountain Earthquake which occurred in Korea and two artificial earthquakes in Paju and Yangsan were simulated. As a result, real time liquefaction hazard maps for whole country were drawn. Finally, we drew two kinds of liquefaction hazard maps in this study. One is the liquefaction hazard map under the same acceleration and the other is the virtual liquefaction hazard map to consider the possible earthquake generation under real time. All maps were drawn successfully. From this research, it was found that this mapping method for macro liquefaction hazard map would be effective. Also, it can give a good countermeasure in the moderate seismic countries like Korea..

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket