Preliminary seismic assessment method for identifying R.C. structural failures

Abstract

In this chapter, an efficient method for rapid preliminary assessment of the seismic vulnerability of reinforced concrete buildings is presented. The method determines the columns’ limiting shear resistance at the critical storey of the structure, by applying a strength assessment procedure associated with typical column details representative of the state of practice from the era of the building’s period of construction and evaluates the severity of seismic displacement demand and the maximum seismic acceleration that the building can sustain by applying a stiffness index assessment. For application of the method, only knowledge of the basic geometric and material properties of the building is required. The proposed method is applied for verification reasons to two reinforced concrete buildings that failed during the 1999 Athens earthquake. It is shown that the proposed method can be used as a diagnostic tool for identification of both the building’s fragility and the prevailing failure mechanism, allowing the engineers to immediately identify the most vulnerable buildings that are likely to collapse in a potentially strong earthquake, as well as to set objectives for their rehabilitation.