Most of the US$14mn will be used to widen a 4.2km stretch in the southern Brazilian state.
The operation will benefit the transport infrastructure trust fund FFSIT.
The Rionegro city government aims to award the contract by October despite an ongoing legal battle over the financing.
The overpass was closed in November after a stretch of the route fell.
Since mid-last year Petrobras adopted a new mechanism to adjust asphalt prices
Investment-focused unit Corficolombia is a player in the country's highways sector via stakes in several concessionaires.