Problems and Possible Solutions of Geophysics in Eurocode 8 Based Soil Classification

The 8th part of the European design standard series — Eurocode 8 (EC 8) was published in 2004. The structural Eurocodes are a set of unified international codes of practice for designing building, which will eventually replace national codes in the European Community. The base of the earthquake resistant structural design in EC 8 is the seismic action i.e. the response spectra of a single freedom system normalized by the ag value. The shape of the response spectrum of an earthquake motion is in close connection with the dynamic properties of the soil. Thus soil characterization is essential in defining the seismic action. In EC 8 the soil classification is based on the properties of the top 30 m of soil mainly on the average shear-wave velocity of this column. The characterization of this column is a near surface problem in geophysics, but need expensive ground investigations for civil engineers. In the last decades several geophysical methods and techniques, mainly (active and microtremor) surface wave ones were developed, which can help to avoid boring drills. However these methods have some limitations which can overcome by combining them, and by using geologic information and new processing techniques for archive geophysical data.