Vol.9, No3, 2009, pp. 181-192
UDC 624.042.7

Abstract

Each civil engineering structure inevitably passes the phase of low cycle fatigue during strong impact loads of the earthquake, and light structures often fail due to loss of local or global stability (local buckling or deflection of structural components.

It is practically impossible to understand the behaviour of buildings subjected to seismic loads without base knowledge of behaviour of structural components during low-cycle fatigue process as well as the global stability of the structures during all phases of earthquake action.

Low cycle fatigue is examined theoretically and experimentally, using damage mechanics concept. Special attention is paid to ultra low cycle fatigue, in the sense Dufailly-Lemaitre. The theory is applied on dampers for strengthening structures damaged in the earthquake. Theoretical considerations are also experimentally checked.

Keywords: hysteresis, damage, damper, structural integrity