Review article

A relationship between R-factor used in the world design earthquake engineering practice and seismic-force-reduction factor K 1 which is used in Response Spectrum Technique of updated editions of the Seismic Building Design Code II-7-81 was analyzed by the author. It is noted that the table no.4 and equation (1) of the Seismic Building Design Code SP 14.13330.2014 give for K 1 two-valued semantic character which can be understood by engineers on two ways. An approach for K 1-factor refinement (in SP 14.13330 formulation) of large-scale construction (LSC) using Pushover curve is suggested. Importance of K 1 choosing with into account of RC shear walls capability to dissipate of earthquake energy is pointed out by the author.