ABSTRACT
Rijkswaterstaat (RWS), the executive agency of the Ministry of Infrastructure and the Environment in the Netherlands, maintains more than 3500 concrete bridges and overpasses in the country’s main highway network. To calculate the life-cycle cost, information on the time and cost of replacement is required. Estimating the remaining lifetime becomes more important as the average age of the structures in-creases and at the same time the use intensifies. RWS is interested in the future budget requirements for the replacement and renovation of the structures. This paper’s first objective is to review the age distribution of concrete bridges and overpasses in the Dutch highway network and to estimate their expected lifetime. A Bayesian analysis using the lifetimes of demolished structures and the ages of structures in use yields an up-date of the structures’ lifetime distribution. Next, the expected replacement costs are computed based on the design lifetime, the best lifetime estimate and the lifetime distribution of the structures. Without taking into account the uncertainty in lifetimes, the future replacement costs of bridges and overpasses show a peak in the period 2040–2060. This makes sense, because most structures have been built in the early 1970s. The replacement costs level out when considering the lifetime uncertainty. However, a significant peak in budget requirements for the 2040–2060 remains and the uncertainty in the replacement costs cannot be neglected.
