This paper presents a summary of current practice and recent developments in the application of passive energy dissipation systems for seismic protection of structures. The emphasis is on the application of passive energy dissipation systems within the framing of building structures. Major topics that are presented include basic principles of energy dissipation systems, descriptions of the mechanical behavior and mathematical modeling of selected passive energy dissipation devices, advantages and disadvantages of these devices, development of guidelines and design philosophy for analysis and design of structures employing energy dissipation devices, and design considerations that are unique to structures with energy dissipation devices. A selection of recent applications of passive energy dissipation systems is also presented.

No abstract

No abstract

This manuscript, the first in a four-part series, describes the response history analysis approach developed for Chapter 16 of the ASCE/SEI 7 Standard and critical issues related to the specification of ground motions. Our approach provides new procedures for demonstrating adherence to collapse safety goals for new buildings (≤10% collapse probability at the MCER shaking level), creating nonlinear structural models, selecting and applying ground motions to the structural model, interpreting computed structural responses, and enforcing acceptance criteria to achieve the collapse safety goal. The ground motion provisions provide the option of using target spectra having more realistic spectral shapes than traditional uniform hazard spectra. Ground motions are developed using a two-stage procedure emphasizing spectral shape in their selection, followed by scaling or matching them to the target, with a modest penalty for matching. Horizontal component motions are applied to the structural model with random components to avoid bias associated with the maximum-component definition of the target spectrum.

No abstract

No abstract

No abstract

SUMMARYThe concept of the hybrid passive control system is studied analytically by investigating the seismic response of steel frame structures. Hybrid control systems consist of two different passive elements combined into a single device or system. The hybrid systems investigated in this research consist of a ratedependent damping device paired with a rate-independent energy dissipation element. The innovative configurations exploit individual element strengths and offset their weaknesses through multiphased behavior. A nine-story, five-bay steel moment-frame was used for the analysis. Six different seismic resisting systems were analyzed and compared. The conventional systems included a special momentresisting frame (SMRF) and a dual SMRF-buckling-restrained brace (BRB) system. The final four configurations are hybrid passive systems. The different hybrid configurations utilize a BRB and either a high-damping rubber damper or viscous fluid damper. The analyses were run in the form of an incremental dynamic analysis. Several damage measures were calculated, including maximum roof drift, base shear, and total roof acceleration. The results demonstrate the capability of hybrid passive control systems to improve structural response compared with conventional lateral systems and to be effective for performance-based seismic design. Each hybrid configuration improved some aspect of structural response with some providing benefits for multiple damage measures. The multiphased nature provides improved response for frequent and severe seismic events.