Abstract

The structures of Quito, Ecuador, are designed for the spectrum of the Ecuadorian code of 2015, or using the study of microzoning of the city of 2012. These spectra consider in general the effect of the blind reverse faults belonging to the city area. In this article, it is pointed out the importance of checking the design for the deterministic control spectra developed for Quito in 2015 based on earthquakes simulated in the blinds faults. In this paper we considered two models of extended plasticity for the structural elements and one model of plasticity for the ADAS and TADAS devices. Then, the technique of multimodal pushover is described, as well as the method of the capacity spectrum used to calculate the performance point of the structure. This structure was initially calculated by using design spectra and it had to be reinforced with ADAS devices in order to avoid its collapse for the control spectrum which has higher ordinates than the design one.

Abstract

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.

Abstract

In this work, the nonlinear dynamic response of RC buildings with energy dissipating devices is studied using advanced computational techniques. A fully geometric and constitutive nonlinear model is used for describing the dynamic behavior of structures. The equations of motion are expressed in terms of cross sectional forces and strains and its weak form is solved using the displacement based finite element method. A suitable version of Newmark’s scheme is used in updating the kinematics variables in a classical Newton type iterative scheme. Material points of the cross section are assumed to be composed of several simple materials with their own constitutive laws. The mixing theory is used to treat the resulting composite. A specific finite element based on the beam theory is proposed for the dissipators including constitutive relations. Finally, several numerical tests are carried out to validate the proposed model.