Methodology for automated GIS-aided seismic microzonation studies

This paper presents an automated methodology for performing geographic information system (GIS)-aided seismic microzonation studies. It presupposes the existence of a geotechnical database containing data from sampling boreholes and in situ geotechnical or geophysical tests. The database has been related to a GIS that is being used only for graphically locating the available borehole and in situ test sites for the study area and for the compilation of digital contour maps. The processing of data and the seismic ground response analyses are automatically performed externally to the GIS and the geotechnical database, via a computer code (created in MS Visual Basic) whose flow chart and characteristics are described in detail herein. This code processes data from the geotechnical database (that has a relational structure and has been created in MS Access here), along with engineering geological and seismological information for the study area. Then, it proceeds in performing the seismic ground response analyses via recently proposed multi-variable relations that duplicate successfully the results of the 1D equivalent linear numerical method. As an application, the paper presents an exemplary GIS-aided seismic microzonation study for an urban municipality of the greater Athens (Greece) area, which reveals the efficiency of the automated methodology and explores its limitations.