The monograph describes the main approaches to assessing the safety of buildings and structures, the design models of which are large-sized schemes, under seismic and emergency impacts. Problems of survivability of building structures are investigated. Explosions, fires, as well as local destruction caused by manufacturing defects, etc. are considered as emergency loads. Calculation methods based on nonlinear dynamic methods are given, which make it possible to perform calculations taking into account all types of nonlinearities in the time domain by direct integration of equations of motion according to an explicit scheme.