Improving systemwide sustainability in pavement preservation programming

Highway agencies seek the participation of the private sector in pavement preservation, to raise revenue, share risks, and reduce project delivery costs. With public-private partnerships (PPP) representing an increasingly common approach for project delivery, recent studies have highlighted the potential of PPP and hybrid contracting (a combination of outsourcing and in-house preservation options) in enabling project-level cost savings. This paper investigates in-house and PPP practices in pavement preservation programming, and proposes a network-level hybrid approach that beneficially combines the two. Using a mixed integer programming-based optimization model and predetermined pavement preservation strategies, a holistic multiyear, multiconstraint, network-scale pavement management system methodology is described and compared with the commonly used year-by-year approach. The goal is to identify the set of recommended in-house and PPP strategies applied to a set of individual road sections, which improve the infrastructure system's sustainability by minimizing the overall preservation cost or maximizing the condition-based benefit across the network, subject to some desired constraints, applied simultaneously. Using data from Indiana, the benefits of the multiyear, multiconstraint optimization are demonstrated, and the results show significant network-level cost savings of the proposed hybrid approach over the in-house and PPP approaches.