Optimal planning of retrofitting interventions on bridges in a highway network

摘要

The aim of the co-ordinated research effort initiated by the Authors consists in developing life-cycle reliability--based methodologies for the management and retrofitting of deteriorating structures and lifelines. As a first step, network systems with Vulnerable nodes are considered. The object of this paper is the optimal planning of retrofitting interventions on bridges included in a highway network, taking into account their deterioration and the limitation of avail- able economic resources. The procedure is illustrated with refer- ence to a 10--node network. It is assumed that the resources avail- able for retrofitting are not sufficient to guarantee the required structural reliability for all bridges throughout the design service life: thence the set of retrofitting interventions is sought that maxi- mizes the network reliability (defined as the probability of main- taining connectivity) under a constraint on the total expenditure. The allocation is performed by means of a dynamic programming procedure.