Fragility curves selection in Central America: A novel methodology using fuzzy analysis

Resumen

The utilization of a fragility curve (FC) can provide a more precise estimation of a structural system's performance level when exposed to seismic hazards. However, selecting an inappropriate FC can significantly affect the accuracy of loss and damage calculations in seismic risk assessments. This article uses a new method to select fragility curves that are better suited to the most prevalent typologies in Central America (CA). To this end, a wide bibliographic search of different vulnerability and seismic risk studies for the Central American region has been conducted. A database was constructed with the parameters of the capacity and FCs available for diverse construction typologies. The novel methodology enables the classification of the FCs based on a multidimensional index that takes into account a collection of pertinent variables related to different characteristics of FCs. These variables are arranged into three major dimensions related to technical suitability of the FC, the suitability for the local system of the potential FCs candidates and the similarity between the building class of the candidate functions and the building class under study. Additionally, a calibration and validation process on the variable scores of the multidimensional index proposed in the new methodology for evaluating and choosing FCs is conducted. The calibration process involves a survey of seismic vulnerability experts worldwide within the field of seismic risk studies. The fuzzy analytic hierarchy process (FAHP) method for multicriteria decision-making (MCDM) is employed to calculate the fuzzy scores or weights based on the experts' survey responses, leading to more objective and dependable scores compared to expert weights. Consequently, the proposed ranking system derived from the new methodology has enabled the identification of the most suitable FCs for the primary construction types in CA. The suggested approach allows for the evaluation of the reliability level of FCs, which is contingent on the curve's class assignment and corresponding score. Additionally, the findings derived from the newly developed multidimensional index facilitate the assessment of the appropriateness of the selected FC, a crucial consideration for researchers investigating seismic vulnerability and risk.