The Cataliytic Importance of the Vertical Component in Earthquake Engineering

Panayotis Carydis
National Tehcnial University of Athens Greece, Athens, Greece

The existing codes for earthquake resistance design of structures protect the structures with abundant safety against earthquakes located at medium distances. The safety is highly reduced for very strong earthquakes at longer distances and there is almost no direct protection for the near field and especially for shallow earthquakes in the epicentral region.
In the present communication it is tried to be demonstrated the catalytic importance of the vertical component of the shaking on the earthquake response of structures build in epicentral regions, either acting independently, or in combination with the other two horizontal components of the seismic motion. In the epicentral regions of the most of the damaging Greek earthquakes of the last decades there is strong evidence of the presence of the vertical seismic component. The paper refers to normal shallow earthquakes, which are the majority of Greek and of many European earthquakes. For these earthquakes a model for the initial tectonic motion is proposed. The resulting motion on the surface of the ground is a superposition of the various well-known types of waves and of the response of the ground to an abrupt tectonic subsidence. Some constructional and design measures are proposed for a tentative protection of existing and new structures in order to confront the vertical component.

AAPG Search and Discovery Article #90072 © 2007 AAPG and AAPG European Region Conference, Athens, Greece