Human safety criteria for risk-based structural design

Abstract

Risk and reliability criteria are well established in many industrial sectors such as the offshore, chemical or nuclear industries. Comparative risk thresholds have been specified to allow a responsible organization or regulator to identify activities, which impose an acceptable level of risk concerning the participating individuals, or society as a whole. The scope of this contribution is to present target reliability criteria based on acceptable human safety levels. Application of theoretical principles is illustrated by examples of railway engineering structures. Initially it is shown how civil engineering structures for which human safety criteria play a role are classified according to Eurocodes. Examples include bridges, tunnels or station buildings. The general concepts for risk acceptance are then briefly reviewed, particularly in their relation to the target reliability criteria. The distinction between the two types of criteria is made: group risk and the acceptance criterion based on the Life Quality Index LQI approach introduced by ISO 2394:2015. The differences between the criteria for new and existing structures are discussed. The application is illustrated by an example of a bridge crossing an important railway line. It appears that while benefits and costs of a private stakeholder or public authority are reflected by economic optimisation, the society should define the limits for human safety to achieve uniform risks for various daily-life activities and across different industrial sectors.

Risk‐Informed Requirements for Design and Assessment of Structures Under Temporary Use

“…The assumption of  = 1 is moreover advantageous since it enables a comparison of the findings with safety criteria based on the Life Quality Index (LQI) according to (ISO 2394(ISO : 2015(ISO , 2015, to be addressed in future studies. A comparison between the F-N curve based human safety acceptance criterion suggested in (fib, 2016) and the LQI-approach, conducted by (Sykora, Holicky, Jung, & Diamantidis, 2018), revealed similar target reliability indices if  = 1 is adopted for the former.…”

The influence of the coefficient of variation on the process reliability of brick production

“…Therefore, with a coefficient of variation of 13%, to ensure reliability 0.977 is required a uniformity coefficient of 1.35. To analyze the dependencies (1)(2)(3)(4)(5)(6)(7)(8)(9) in Figure 1 and Table 1, the dependence of the uniformity coefficient for ensuring reliability V on the value of the variation coefficient is shown.…”

“…In this regard, the study of the Influence of the variation coefficient on the building structures reliability is of scientific interest and practically an important research task. Risk and reliability criteria are well known in many industrial sectors such as offshore, chemical or nuclear industries [1]. The most effective verification methods are based on advanced probabilistic approaches, including risk assessment methods taking into account the actual properties of the structure and the associated consequences of destruction.…”

The centrality of engineering codes and risk-based design standards in climate adaptation strategies

“…The suite of periodic IPCC reports, beginning in 1990 through 2021 created a climate model, scenario-driven 'top-down' analytical paradigm. This was deemed by many engineering practitioners as unsuitable for most water resources management problemsparticularly those related to site-specific infrastructure design (Kundzewicz & Stakhiv, 2010;Stakhiv, 2011;Retief et al, 2013;Sykora et al, 2017;Sykora et al, 2018;Underwood et al, 2020).…”

“…All of these upgrades of standards and other pathways are being vigorously pursued by many federal agencies in both Europe and the U.S. Safety factors and design redundancies are another direct way that engineers have always used to deal with uncertainties of natural hazards, modeling and data collection. Since uncertainty analysis is a well-accepted part of engineering practice that encompasses codes, standards and associated regulatory processes, it should be possible to deal with the growing uncertainty of future climate-related design values by identifying and increasing safety factors when evidence points towards the likelihood of increased climate risks over the lifespan of a given structure (Yen & Tung, 1993;Tung, Yen & Melching, 2006;Sykora et al, 2017;Sykora et al, 2018). These safety factors inherently account for increased project and system robustness, used to minimize the risk of a major catastrophe from occurring.…”