Modellazione non lineare di strutture esistenti in c.a.:confronti con risultati sperimentali

This paper discusses about some aspects regarding non linear behavior of RC existing structures with smooth bars. Experimental responses of an internal beam-column joint designed only for vertical loads (Braga et al. 2009a) and of some columns (reported online into Pacific Earthquake Engineering Research Center database) are compared with analytical predictions. The BGL model (Braga et al. 2006) recently implemented into OpenSees libraries (Braga et al. 2009b) and a simplified model to study bond-slips in smooth bars are used. The latter is aimed to obtain an evaluation of structure behavior by using non linear both static and dynamic analyses. Starting from a previous work (Braga et al. 2004), analytical formulation of the model has been developed more in detail for hooked ends of longitudinal bars. To this purpose, tensile stress-slip relationships by varying the hook anchorage are shown.