Some implications of strong motion accelerograms obtained in Romania

Abstract

The regulatory literature concerning earthquake protection reveals the fact that the design parameters are prescribed assuming implicitly a linear performance of the ground–structure interface. Thereafter, the upper part of the ground–structure system may be eventually designed recognizing explicitly the post-elastic performance of the upper part referred to. On the contrary, the scientific concern during recent decades has shown that non-linear interaction during strong earthquakes is frequently unavoidable and, perhaps, even beneficial for the capacity of structures to withstand strong seismic action. The data at hand reveal the fact that nonlinear dynamic interaction had to occur in some cases, at least in terms of partial uplift of foundations. The implications of the potential occurrence of nonlinear performance of ground – structure systems lead logically to the need to revise the philosophy of regulatory documents. This requires in its turn an examination of the topology of transfer to the ground of the seismic forces.