CRITERIOS DE DISEÑO SÍSMICO DE EDIFICIOS DE CONCRETO REFORZADO CON PLANTA BAJA DÉBIL UBICADOS EN LA CIUDAD DE MEXICO

Abstract

A weak first storey building is the one that owns an abrupt change of rigidity in the height of the building; in the city of Mexico this type of buildings corresponds generally to concrete reinforced apartment buildings with basement parking places. There is a significant increase in the construction of structures with soft flat in the city of Mexico, in spite of knowing that this structural system has problems of seismic behavior by the enormous change in stiffness between the upper floors and the first. As result of censuses on damaged buildings made after the earthquake of 1985, noted that 8% of 330 buildings collapsed in the city of Mexico corresponded to buildings soft floor (Esteva Maraboto, 1987), which can be interpreted as a structure which requires study because it is very susceptible to seismic damage This research aims to study the structural behavior of that system taking into account the characteristics of the soil in the Centre of the city of Mexico and his seismic accelerations. The nonlinear behavior of a characteristic structure framework result of three-dimensional elastic analysis studies. The framework is studied using seismic analysis in the domain of the time, using the SCT 1985, apart from using simulated with stochastic processes modulated with Green's function logs earthquake as seismic records. Step-by-step analysis results in damage configurations, hysteretic shear basal behavior configurations basal and distortions Subsequently performs local damage analysis, modeling a concrete reinforced beam through a model known as Mazars material damage, using finite element method and the results are hysteretic curves behavior of material, as well as efforts in finite elements compared with efforts in literature known as curves images Park & Paulay book. The work is divided into three stages: the first performs a conventional linear elastic analysis together with a design based on the regulation for the construction of the city and its complementary technical standards; the second stage performs a non-linear analysis of structure and phase III builds a local model of the worst concrete beam, which is analyzed by the method of finite elements.