Regional seismic risk assessment based on the Unified Scaling Law for Earthquakes: The Lake Baikal railway system

Abstract

Seismic hazard assessment (SHA) and evaluation of seismic risk (SR) require an adequate understanding of the actual distribution of earthquakes over magnitude, space, and time ranges. Neo-deterministic seismic hazard assessment (NDSHA) methodologies have been developed to improve the reliability and accuracy of reproducible seismic hazard maps. In the last decade, the application of NDSHA in many regions of the world has confirmed the availability of reliable and effective input for mitigating object-oriented earthquake risks NDSHA results have passed intensive testing by historical evidence and realistic modelling of scenario earthquakes. We used two NDSHA tools – (i) Unified Scaling Law for Earthquakes (USLE) and (ii) anisotropic propagation of the seismic effect – to evaluate SR for the Lake Baikal regional railroad system represented by Open Street Map (OSM) data of tracks, bridges and tunnels on the basis of seismic hazard maps of maximum macroseismic intensity expected in 50 years with 10%, 5%, and 1% probability of exceedance. We compare the achieved USLE−based results with the SR evaluations based on the General Seismic Zonation 2016 maps at identical levels of probability of exceedance.