Reliability-based risk factors

David G. Elms

doi:10.5459/bnzsee.13.1.3-13

David G. Elms University of Canterbury, Christchurch, New Zealand

DOI: https://doi.org/10.5459/bnzsee.13.1.3-13

Abstract

Risk factors are used in some codes to allow for the  higher than normal consequences of the failure of essential or important structures. A classification of high-risk structures is given, based on different reasons for high importance. Risk factors are then related to reliability factors, defined as the increases in reliability required compared with that for a normal building. By assuming reasonable values for reliability factors, a set of risk  factors is derived. Some of these correspond closely to those specified in the New Zealand code, while others differ markedly.

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