SEISMIC MONITORING AND THE EFFECTS OF SOIL-STRUCTURE INTERACTION FROM RESPONSE SPECTRA

Considering the soil-structure interaction phenomena, in case of the rigid structure founded on deformable ground, some important changes occur in its response values. Some specific aspects are investigated: kinematic and inertial interaction effects, the fundamental period of a structure, the response spectra that take into account the interaction effects, the transfer function between the structural relative displacements (at the top) and the free-field motion, the differences from the free field motion to the structure input motion, understanding of the distribution of forces and displacements in the structure etc. The evaluation of soil-structure interaction effects is made through the difference between the actual response of a structure, from seismic monitoring and theoretical analysis, and the response of the structure with a fixed base, and it also result from the spectral ratios top/free field and top/base. Seismic instrumentation of building is used for seismic data acquisition, both on the seismic characteristics of the site and on the dynamic response characteristics of structure.