Evidence indicates that the dynamic behavior of Rigid Wall – Flexible Diaphragm (RWFD) structures is dominated by the diaphragm’s response instead of the walls’ response, and this is a significant departure from the underlying assumptions of the widely used equivalent lateral force method in current building codes. RWFD buildings are common in North America and other parts of the world, and inc...

The mechanism of earthquake energy input to building structures is clarified by considering the surface ground amplification and soil-structure interaction. The earthquake input energies to superstructures, soil-foundation systems and total swaying-rocking system are obtained by taking the corresponding appropriate free bodies into account and defining the energy transfer functions. It has been...

The importance of our infrastructure systems as the foundations for our civilization, maintaining the health of our society and serving as the engines for our economy has been articulated by the NSF and other government agencies since the 1970’s. The National Earthquake Hazards Reduction Program (NEHRP), created by the US Congress by the Earthquake Hazards Reduction Act of 1977 was based on rec...

A method is offered to estimate downtime (the time to restore a facility to operability, not total repair time) for second-generation performance-based earthquake engineering. It applies in cases where downtime is primarily controlled by nonstructural systems (although red-tagging and lifeline failure are addressed); restoration begins immediately after the earthquake; and components are repair...

Pulse period of earthquake records has been known as a key parameter in seismology and earthquake engineering. This paper presents a detailed characterization of this parameter for a special class of earthquake records called pulse-like ground motions. This type of motions often resulting from directivity effects is characterized by a strong pulse in the velocity time history of motion, in norm...