ABSTRACT
ABSTRACT: The main objective of bridge isolation is the protection of the substructure by reducing the force demands and improving its energy dissipation capabilities for limiting the displacement demands. This paper presents the study of typical reinforced concrete bridges in Mexico aimed at determining the isolator parameters for obtaining elastic or limited inelastic behavior of the piers. A parametric analysis of the seismic behavior of short and medium span bridges with lead rubber bearings isolators, using the most common structural types built in Mexico was carried out. The inelastic seismic response of parameterized bridge models with lead rubber isolators was determined. A three-span continuous bridge fully isolated with lead-rubber bearings at each abutment and column bent was analyzed; the bridge deck is presumed rigid with transversal diaphragms in the middle and at the end of each span. The lengths of the spans 1 to 3 are assumed to be equal each other in the range of length from 25 to 40 meters with span length increments of five meters, which give four models to study. The roadway is 10 m width in all the analyzed models. For each bridge length, four possible periods of the structure is considered by varying the column heights in 4, 7, 10 and 15 meters.
