We present a sensitivity analysis on the impact of input parameters and methods used on the results of a probabilistic seismic hazard assessment (PSHA). The accurate estimation of the parameters in recurrence models (declustering and fitting methods), along with the selection of scaling relationships for determining maximum magnitude and the selection of ground motion models (GMMs), enhance control over epistemic uncertainties when constructing the logic tree, minimizing final calculation errors and producing credible results for the study region. This study focuses on Central America, utilizing recent data from seismic, geological, and geophysical studies to improve uncertainty analyses through classic statistical methods. The results demonstrate that proper fitting of the recurrence model can stabilize acceleration variations regardless of the declustering method or b-value fitting method used. Regarding scaling relationships, their low impact on the final results is noted, provided the models are tailored to the tectonic regime under study. Finally, it is shown that the GMM contributes the most variability to seismic hazard results; therefore, their selection should be conditioned on calibration with observed data through residual analysis where region-specific models are not available.

This study presents a comprehensive methodological framework that encompasses all stages required to evaluate the structural response to potential seismic motions. The proposed approach involves the estimation of seismic hazard at the site of interest, the disaggregation and definition of control earthquakes, the characterization of local site effects, the assessment of possible resonance phenomena, and the comparison between response spectra derived from probable seismic scenarios and the design spectra of the buildings, leading to conclusions regarding structural safety. The methodology integrates instrumental measurements of soil and building vibration periods with analytical procedures to define response spectra consistent with expected seismic scenarios. It was applied to buildings of special importance located in Guatemala City, particularly within the University of San Carlos of Guatemala (USAC) campus, with the aim of evaluating their structural safety and developing retrofitting criteria when necessary. The implementation began with a probabilistic seismic hazard analysis (PSHA) to identify control earthquakes that make the largest contribution to hazard for a 475-year return period, followed by the estimation of rock response spectra. A seismic microzonation study was then conducted to characterize local site conditions. Instrumental vibration measurements of the soil and structures were obtained, and a soil–structure interaction analysis was carried out to evaluate potential resonance effects. The results showed no evidence of resonance. Finally, soil response spectra derived from the control earthquakes were compared with the design spectra defined by the AGIES 2024 structural safety standards. The results confirmed that the design spectra adequately envelope the computed response spectra for all soil–structure combinations. The proposed methodology is replicable and can be used to assess the seismic design adequacy of other buildings, providing a rational basis for retrofitting decisions when design spectra do not fully encompass the expected seismic response.

This study compares methods that address two key aspects: how to quantify geological information and transfer it to recurrence models, and how to distribute the seismic potential between two types of sources. These methods are as follows: 1) the mom-rate method, 2) the mom-slip method, 3) the Hybrid Method Proposed (MHP), and 4) the method to build hazard models including earthquake ruptures involving several faults named Seismic hazard and earthquake rate in fault systems (SHERIFS). The results show that the peak ground acceleration (PGA) values increase significantly in the vicinity of the faults, when these are modeled as independent sources in the hybrid methods, reaching, in some cases, to be multiplied by a factor of 2.

This study develops a comprehensive workflow for the analytical seismic vulnerability and structural performance assessment of a special-importance steel building located in a region of elevated seismic hazard in southern Spain. The work addresses the need for reliable analytical methodologies for facilities that must remain operational during earthquakes. The proposed framework integrates a probabilistic seismic hazard assessment, including uniform hazard spectra and hazard disaggregation to identify control earthquakes. Additionally, an analytical vulnerability assessment under the Spanish seismic design code, NCSE-02, is performed. Operational modal analysis and nonlinear analysis are combined to retrofit the numerical model of the building and capture the building’s realistic seismic response. The resulting demand spectra are derived from site-specific ground-motion scenarios for Los Barrios (Cádiz, Spain). Retrofitting strategies are designed and assessed to ensure compliance with the code-defined performance requirements. Results indicate that the retrofitted model reproduces the building’s dynamic behaviour with improved reliability, and that the strengthening interventions enhance seismic performance while still allowing moderate damage in specific components. These findings highlight the importance of analytical vulnerability approaches and code-oriented retrofitting when evaluating the seismic performance and vulnerability of essential facilities. The study demonstrates that rigorous analytical methods provide a robust basis for defining seismic vulnerability in special-importance buildings and support improved decision-making for structural safety and resilience.