The Federal Highway Administration in the USA are searching for ways to increase the lifespan of roads and roadways (including bridges) as well as reducing the need for road maintenance where work zones lead to increased pollution from traffic jams.
Research is under way to build roads with a life of 50 years and bridges with a life of 100 years. Such targets are achievable according to Charles Churilla, research programme manager. This year they have a budget of US$400 million to work with, down approximately US$4.4 million from last year.
They accept the fact that the use of improved materials and construction practices may cost more up front, but have the potential to save money down the track. The cost and time savings brought about by reduced maintenance will overshadow the initial costs, as well as improving driver safety and reducing delays due to maintenance.
States such as Ohio and Kentucky have been getting contractors to experiment with longer lasting materials and making bridge sections in factories rather than on site.
One initiative introduced by ODOT involves paying incentives to contractors a bonus if they achieve certain strength and density specification for concrete. Similarly, they can be docked for not achieving these target figures. This initiative is currently being implemented in a pilot project involving 5 bridges in Ohio.
Other similar initiatives include paying contractors a bonus to complete work ahead of schedule, while contractors are also guaranteeing the quality of their work.
On the materials side, asphalt and concrete are being tested side by side to see which lasts longer. Composite materials are being used in bridge constructions, while bridge sections are being manufactured off site, only arriving on site for assembly.