Constitutive and Geometric Nonlinear Models for the Seismic Analysis of RC Structures with Energy Dissipators

Nowadays, the use of energy dissipating devices to improve the seismic response of RC structures constitutes a mature branch of the innovative procedures in earthquake engineering. However, even though the benefits derived from this technique are well known and widely accepted, the numerical methods for the simulation of the nonlinear seismic response of RC structures with passive control devices is a field in which new developments are continuously preformed both in computational mechanics and earthquake engineering. In this work, a state of the art of the advanced models for the numerical simulation of the nonlinear dynamic response of RC structures with passive energy dissipating devices subjected to seismic loading is made. The most commonly used passive energy dissipating devices are described, together with their dissipative mechanisms as well as with the numerical procedures used in modeling RC structures provided with such devices. The most important approaches for the formulation of beam models for RC structures are reviewed, with emphasis on the theory and numerics of formulations that consider both geometric and constitutive sources on nonlinearity. In the same manner, a more complete treatment is given to the constitutive nonlinearity in the context of fiber-like approaches including the corresponding cross sectional analysis. Special attention is paid to the use of damage indices able of estimating the remaining load carrying capacity of structures after a seismic action. Finally, nonlinear constitutive and geometric formulations for RC beam elements are examined, together with energy dissipating devices formulated as simpler beams with adequate constitutive laws. Numerical examples allow to illustrate the capacities of the presented formulations.This research was partially supported by the European Commission, CEE–FP6 Project FP6-50544(GOCE) “Risk Mitigation for Earthquakes and Landslides (LESSLOSS)”; by the Spanish Government (Ministerio de Educación y Ciencia), project BIA2003-08700-C03-02 “Numerical simulation of the seismic behaviour of structures with energy dissipation devices”; project MAT2003- 09768-C03-02 “Delamination of reinforced matrix composites (DECOMAR)”; project BIA2005-06952 “Study of composite materials for design, reinforcement and retrofit of civil engineering structures (RECOMP)”; by the Spanish Government (Ministerio de Fomento) “Numerical simulation methodology for the reinforced concrete behavior structures reinforced with composite materials”, and by the collaboration framework between CIMNE and AIRBUS, project PBSO-13-06 “Innovative finite element methods for non linear analysis of composite structures (FEMCOM)”