STAINLESS STEEL REBAR FOR SEISMIC APPLICATIONS

Alberto Franchi1, Pietro Crespi1, Aldo Bennani2 and Marco Farinet2

1Politecnico di Milano, Milan, Italy
E-mail: alberto. franchi@polimi. it, pietro. crespi@polimi. it
2Cogne Acciai Speciali Aosta, Italy
E-mail: aldo. bennani@cogne. com, marco. farinet@cogne. com

Abstract

This paper is meant to present the mechanical characteristics of austenitic stainless steel rebars under monotonic and cyclic loadings. Furthermore, some results concerning the experimental tests on column prototypes subjected to cyclic loadings are presented, with the intent of comparing with results obtained on analogous columns reinforced with standard high ductile carbon steel rebars.

Keywords: stainless steel, rebar, ductility, cyclic loading, seismic loading

1. Introduction

Stainless steel rebars are used primarily in reinforced concrete structures because of their corrosion resistance. It is well known from the literature (Park et al., 1982; Pipa and Carvalho, 1990; Monti and Nuti, 1992; Macchi et al., 1996; Franchi et al., 1996; Pantazopoulou, 1998; Riva and Franchi, 2001; Riva et al., 2001) that, for seismic applications, the reinforcing steel has to provide enough ductility, i. e. plastic elongation at ultimate stress, and enough strain hardening, measured by the ratio of ultimate stress over yield stress. At the same time, it is very well known from the literature, that austenitic stainless steel shows a remarkable degree of ductility and strain hardening. The question, therefore, comes out as follows: how does behave austenitic stainless steel reinforcement under seismic loading conditions?