This investigation focuses on the seismic evaluation of low-midrise reinforced concrete buildings in San
Salvador, considering the inelastic demand defined by the current seismic design code (NTDS-94).
Moreover, the latest Probabilistic Seismic Hazard Assessment (PSHA) for the country, which will be
the base for the new seismic code, was used. The implemented methodology was the Probabilistic Based
Earthquake Engineering (PBEE) framework, which involves a holistic overview of the performance
integrating hazard, structural, and damage analysis. Four simplified framed structures treated as a single
degree of freedom systems were studied, two are based on El Salvador seismic standard, and the others
are based on Japanese seismic provisions. The above with the intention to compare the influence of the
hazard definition and the required capacity specified in each building code on the building's performance.
Two approaches were employed to give a solution to the PBEE basic formulation; numerical integration
and approximate analytical solution. We calculated the probabilities of limit state exceedance in 50 years
in terms of inter-story drift ratios. Based on the results, the probabilities of exceeding the design limit
drift imposed by El Salvador's seismic code of 0.015 rad are more than 5% for both Salvadoran SDOF
systems (6-story and 10-story buildings) calculated using both approaches. We observed that El
Salvador models have higher probabilities of exceeding safety limits than Japanese models. Hence, the
influence of the seismic hazard curve and the seismic demand, which in the case of El Salvador depends
on the response reduction factor R, was evident. The approximate solution derived more conservative
results in the performance of the building models studied.
Keywords: PBEE, Reinforced Concrete building, Failure probability.