Microalloyed steels in building construction

Reinforced concrete buildings or steel buildings, which are subjected to numerous loads in their life time, must be designed to meet the performance objectives during construction and during the whole life of the structure, including the capacity to resist catastrophic loading events. Recent advances in steelmaking technologies have resulted in microalloyed steel products with superior properties which can easily and economically meet these multiple building performance demands. The first part of this paper summarizes the structural design concepts and the general design considerations associated with building structures. Seismic design provisions and the capacity design concepts are explained. The second part of the paper looks at the function of rebar, historical development of rebars, and acceptance criteria for reinforcing steels in North American building codes and construction. The third part of the paper reviews the historical development of structural steels, and the North American material specifications for structural steels. The stability, ductility, and the fire resistance requirements of structural steel members and the relevance of microalloyed structural steels in building construction are also discussed. The paper argues that niobium microalloying is the key to achieving superior properties in such steels. (AU) Copyright © 2015 Companhia Brasileira de Metalurgia e Mineração (CBMM) All rights reserved.