A Nonlinear Analysis for the Retrofitting of a RC Existing Building by Increasing the Cross Sections of the Columns and Accounting for the Influence of the Confined Concrete

Abstract:

In the present paper a nonlinear analysis is presented for the retrofitting of a Reinforced Concrete (RC) building by increasing the cross sections of some columns and by considering the effects of the confined concrete in the nonlinear model. The adopted design methodology is based on a displacement based approach in order to ensure the compatibility condition between the displacement capacity of the structure and the displacement demand according to the seismic codes. The displacement demand is achieved through the increase of the cross section of the RC columns with a consequent increase of the lateral stiffness of the existing structure. In the case of the retrofitted columns the disposition of the reinforcement makes realistic to consider the beneficial contribution of the confinement action of the transversal reinforcement with respect to the internal core. Consequently in the nonlinear analysis the influence of the confined concrete has been considered in the definition of the proper constitutive law for the retrofitted columns. An analysis of the beneficial effects of this confinement action on the nonlinear capacity curve of the structure is described and details are illustrated on the possible ways to take into account the confinement action in the verification of the inelastic behavior of the retrofitted structure.

• Periodical: Applied Mechanics and Materials (Volumes 204-208)
• Pages: 3604-3616
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.204-208.3604
• Online since: October 2012
• Authors: Donato Cancellara*, Fabio de Angelis
• Keywords: Non-Linear Analysis, RC Building, Seismic Retrofitting

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