Alexander Cedergren

Vulnerability analysis of interdependent critical infrastructures : case study of the Swedish railway system

Critical infrastructures provide essential services which enable our society to function. Disruptions in infrastructures can have widespread effects, not only for the originating infrastructure but also, through mutual dependencies, for other infrastructures. Identifying vulnerabilities inherent in these system-of-systems is thus highly critical for the proactive management and avoidance of future crises. A modelling approach for interdependent technical infrastructures is proposed and three perspectives for the analysis of vulnerabilities are introduced, addressing the complexities associated with comprehensively analysing technical interdependent infrastructures. An empirical analysis of the railway system in southern Sweden is conducted, a system consisting of seven interdependent supporting systems. It is concluded that the proposed modelling approach and the three perspectives of vulnerability analysis give valuable insights for the proactive risk management of technical infrastructures.

Designing Resilient Infrastructure Systems: A Case Study of Decision-making Challenges in Railway Tunnel Projects

In order to minimise the impact on society in the case of severe disturbances affecting infrastructure systems, it is essential that these systems are resilient to failures, i.e. that they are able to continue operations or quickly recover a stable state after a major mishap. Numerous opportunities for taking measures to increase resilience of infrastructures exist already in the design phase of new elements in these systems. This paper therefore investigates to what extent resilience of the railway system is considered at the design stage of new railway tunnels in Sweden. The case study builds upon interviews with key stakeholders involved in the decision-making process regarding safety measures in six railway tunnel projects, comprising a total of 28 tunnels (representing the majority of contemporary railway tunnel projects in Sweden). The theoretical perspective is based upon insights from the fields of resilience engineering and risk governance. The results revealed that power relations between the different stakeholders largely influenced the decision-making process in the studied railway tunnel projects. Diverse roles and perspectives among these actors led to disagreements in the majority of the projects. As a result, both of the key stakeholders experienced that they were trapped in different kinds of double binds, i.e. situations requiring a choice between equally bad outcomes. These double binds, and the significant influence from local actors on decision-making, resulted in a restricted consideration of the system’s resilience on the regional and national levels. These findings underline the important relationship between decision-making at the local level in each railway tunnel project and the impact from these decisions on the system’s resilience at the global level. The paper therefore contributes to increased understanding of the way that micro-level decisions affect macro-level characteristics of complex socio-technical systems.