The Mdesign for engineering applications of Neo-Deterministic Seismic Hazard Assessment (NDSHA) within the China Seismic Experimental Site (CSES)

Seismic Hazard Assessment (SHA) serves as a fundamental tool for conservatively evaluating earthquake effects to safeguard critical infrastructure and human settlements. At the core of SHA methodologies lies the crucial task of quantifying and parameterizing the maximum potential earthquake magnitude. This study introduces an operational approach using a design magnitude (Mdesign) with a tunable safety factor (γEM) to define the maximum potential magnitude. Based on Neo-deterministic Seismic Hazard Assessment (NDSHA) computations, we scrutinize the performance of the earthquake magnitude safety factor in the determination of the maximum potential magnitude for providing an envelope of seismic hazard levels that will not be exceeded, considering present understanding of seismicity and tectonic settings in the China Seismic Experimental Site (CSES). Results suggest a validated relationship Mdesign = Mmax + 0.7, which to date indicates a safety factor equal to 2.8 for the CSES. On the basis of the validated relationship, we obtain the evaluation of seismic hazard considering the maximum potential magnitude within CSES. By comparison, the same safety factor has also been verified for the Italian territory, indicating that it is independent of the study region. Although the Italian region exhibits a lower maximum magnitude, the same safety factor is still validated there, demonstrating that this relationship is also independent of magnitude range. This work not only deepens existing methods for determining the maximum potential magnitude but also provides a reliable, evidence-based approach that is both scientifically rigorous and practically applicable to probabilistic and deterministic seismic hazard assessments.