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Buckling-restrained braces (BRBs) have recently become popular in the United States for use as primary members of seismic lateral-force-resisting systems. A BRB is a steel brace that does not buckle in compression but instead yields in both tension and compression. Although design guidelines for BRB applications have been developed, systematic procedures for assessing performance and quantifying reliability are still needed. This paper presents an analytical framework for assessing buckling-restrained braced frame (BRBF) reliability when subjected to seismic loads. This framework efficiently quantifies the risk of BRB failure due to low-cycle fatigue fracture of the BRB core. The procedure includes a series of components that: (1) quantify BRB demand in terms of BRB core deformation histories generated through stochastic dynamic analyses; (2) quantify the limit-state of a BRB in terms of its remaining cumulative plastic ductility capacity based on an experimental database; and (3) evaluate the probability of BRB failure, given the quantified demand and capacity, through structural reliability analyses. Parametric studies were conducted to investigate the effects of the seismic load, and characteristics of the BRB and BRBF on the probability of brace failure. In addition, fragility curves (i.e., conditional probabilities of brace failure given ground shaking intensity parameters) were created by the proposed framework. While the framework presented in this paper is applied to the assessment of BRBFs, the modular nature of the framework components allows for application to other structural components and systems. [ABSTRACT FROM AUTHOR]

The article reports on the release of a practice guide titled "Fractography of Ceramics and Glasses" by the U.S. Department of Commerce's National Institute of Standards and Technology (NIST), which aims to promote the use of fractography for the analysis of brittle materials. It notes that the page guide explores practical aproaches for fracture analysis and emphasizes the importance of fractography to other applications. The publication also contains 725 images and drawings to help fractographers in identifying patterns.

Calls for papers for the Third International American Society of Testing Materials Symposium on Fatigue and Fracture Mechanics on May 16-19, 2005, in the U.S. Aim of the symposium to promote discussion and dissemination of the state-of-the-art advances in the multiscale modeling and characterization of the creep and fatigue and fracture response of materials and structures; Instructions for publication of symposium papers; Contact information.