Collapse-Proof Seismic Design

Collapse-proof structures cannot be collapsed by any of the recorded ground motions. Collapse-proof structures are characterized by very high values of seismic toughness and damping. This chapter discusses the seismic design of a collapse-proof structure. The 11 response spectra are enclosed within a smooth envelope, as shown by the thick magenta curve. Envelope response spectra are similarly generated for other values of damping. Buckling-restrained braces (BRB) can yield both tension and compression. A normal brace buckles in compression before it can yield. But a BRB has an outer encasement, which prevents it from buckling, whereas the inner core yields in compression. The capacity and damping curves are regenerated using new values of elastic period and damping. Soil-structure interaction increases the elastic period of the system and increases its initial (elastic) damping.