Acceptable risk criteria for infrastructure protection

This paper reviews risk-based approaches to assessing the risk acceptability and cost-effectiveness of protective measures for infrastructure. The paper describes three risk acceptance criteria based on fatality risks, failure probabilities and net benefit assessment. These criteria can be applied to any item of infrastructure such as buildings, bridges, dams, offshore platforms, etc. and also applies to any manmade or natural hazard such as earthquakes, cyclones, terrorism, floods and so on. The decision support framework accompanying these risk acceptance criteria considers hazard and threat probabilities, value of human life, physical and indirect damages, risk reduction and protective measure costs. This has specific utility for the safety and economical design and assessment of new and existing protective structures against shock and impact loading. Risk assessments are conducted for a bridge over an inland waterway where the hazard is ship impact and a building subject to terrorist attack. The illustrative examples showed under what combination of risk reduction, and fatality and damage costs the fatality and failure risks would be acceptable, and when protective measures would be cost-effective

Reviewing the past to learn in the future: Making sense of design errors and failures in construction

Design errors can severely jeopardise safety and contribute to failures in construction and engineering projects. Such failures can have devastating economic, environmental and social consequences. Significant efforts have been made to reduce the incidence of failures through learning from previous disasters and events by modifying building and engineering codes and standards accordingly. Design errors, however, remain an innate feature of construction and engineering projects despite the considerable amount of knowledge that has been accumulated to date. Most errors are identified during construction and require rework, but there is always a potential for some to remain undetected and contribute to failure, and as a result potentially contribute to accidents and loss of life. An examination of the literature research suggests that a series of pathogenic influences contribute to errors and failure. Thus, this paper article examines the circumstances and issues that contributed to a series of construction and engineering failures to enable development of a learning framework that can be used to mitigate design errors and potential failures and accidents. © 2013 Copyright Taylor and Francis Group, LLC