OPTIMAL PLANNING OF RETROFITTING INTERVENTIONS ON BRIDGES IN A HIGHWAY NETWORK

The aim of the co-ordinated research effort initiated by the Authors c onsists in developing life-cycle reliability-based methodologies for t he management and retrofitting of deteriorating structures and lifelin es, As a first step, network systems with vulnerable nodes are conside red. The object of this paper is the optimal planning of retrofitting interventions on bridges included in a highway network, taking into ac count their deterioration and the limitation of available economic res ources. The procedure is illustrated with reference to a 10-node netwo rk. It is assumed that the resources available for retrofitting are no t sufficient to guarantee the required structural reliability for all bridges throughout the design service life: thence the set of retrofit ting interventions is sought that maximizes the network reliability (d efined as the probability of maintaining connectivity) under a constra int on the total expenditure. The allocation is performed by means of a dynamic programming procedure, (C) 1998 Elsevier Science Ltd, All ri ghts reserved.