Analysis of the seismic response of plan-irregular R. C. building

This chapter presents a deep seismic analysis of the seismic response of a plan irregular reinforced concrete low rise building. The building was designed according to the current Venezuelan seismic code, and represents the structural typology of low rise residential buildings. Two kinds of analysis were performed in order to evaluate the seismic response; the first one was the non linear pseudo-static analysis using a first mode path of lateral forces distribution. The second was the non-lineal dynamic analysis using synthetic design-spectrum compatible accelerograms, scaled in order to associate them with three specific limit states. These limit states were evaluated through the interstorey drifts reached by the structure under the seismic action. Another important feature evaluated was the torsional effects of the seismic action on the whole structure, a direct relationship between the plan irregularity and the twisting moments was found. In order to improve the original structural design another building was proposed following new guidelines obtained from recent research. This building had shown a better seismic behavior than the original one. Finally, a complete set of fragility curves are computed applying a new procedure based on the dynamic results.