Value of Information for SHM of a Prestressed Concrete Bridge with Stress Corrosion Cracking Risk

Structural Health Monitoring (SHM) is increasingly considered for bridge management, but its practical adoption is often hindered by uncertainty regarding the economic value of monitoring information. This paper applies the concept of Value of Information (VoI) to quantify the decision value of SHM for the Castroper Hellweg bridge in Bochum, Germany, a prestressed concrete road bridge affected by stress corrosion cracking concerns. The proposed framework combines Bayesian updating with decision theory to evaluate management actions in terms of expected costs. VoI is defined as the reduction in expected cost when decisions are made with SHM information rather than prior knowledge alone. Because interventions such as closure, rehabilitation, or replacement involve one-off consequences, the resulting VoI is treated as an event-based quantity and subsequently annualized for break-even analysis. A baseline case is formulated using discrete structural states, monitoring outcomes, prior prob-abilities, likelihood functions, and consequence costs. Based on this setup, annual and cumulative net benefits are evaluated over the monitoring period, yielding an economic break-even after approximately 3.3 years. The robustness of this result is then assessed by a deterministic sensitivity analysis of representative parameters from the prior model, the monitoring model, and the assumed frequency of decision-relevant situations. The results show that the economic viability of SHM depends strongly on prior risk, monitoring quality, and the consequences of underreaction, demonstrating the usefulness of VoI as a transparent framework for economically rational bridge management decisions.