Pavement is an important part of the urban planner’s quest for a sustainable community. So it’s not surprising that transportation engineers have been experimenting with precast pavements for more than 40 years in an effort to create more durable roads. While many of these projects have been limited to rapid tear out and replacement efforts, there’s a renewed interest in using these off-site fabricated panels in new construction.

The FHWA has identified Precast Concrete Pavement Systems (PCPS) as a viable pavement technology. Several reports have identified how PCPS’s beneficial characteristics can enhance a community’s resiliency.

Transportation departments have used PCPS installations on projects to speed up the construction scheduling. PCPS set-ups often require smaller operational footprints reducing the size of the affected area and also increasing safety by reducing exposure to both workers and the traveling public.

But the strongest case for more PCPS projects as a tool in creating sustainable communities is based on economics. PCPS can match the durability of traditional cast-in-place pavements but require less embedded energy to install. Since PCPS panels are cast in a factory-like setting, they can be produced more efficiently and with tighter mix design requirements. PCPS may exceed service life performance when compared to traditional pavements. And should there be a repair needed, PCPS offer shorter shutdowns and faster completion schedules. There are also reduced owner costs associated with reduced congestion delays and less community disruption.

For contractors, an increase in PCPS projects is providing an economy of scale which is helping to reduce construction costs. In the last five years, manufacturers and engineers have developed at least four propriety systems that have been referenced by the FHWA. Offsite manufacturing offers contractors opportunities to reduce job site work force size.

The combination of offsite manufacturing with in place construction is becoming more common. For example, the California Department of Transportation (Caltrans) included PCPS on a large paving project. The Pavement and Slab Replacement Project on the Foothills Freeway (I-210) near Los Angeles includes two lanes being replaced with PCPS . Caltrans awarded the project to Flatiron West of Chino Hills, Calif. Oldcastle Precast’s plant located in Fontana, California will cast 6,500 precast highway pavement slabs for this $148 million project.

The plans call for the distressed slabs in the numbers one and two lanes to be replaced with Individual precast slabs. Flatiron crews are installing the pavement slabs as an overnight process. Crews shut down about 1000 feet of highway daily to create a moving work area. They first cut out and remove about 630 feet of pavement. They next place fresh concrete to create sub base in the excavation. After the concrete base achieves the required strength, approximately 1 hour later, about 30 precast concrete pavement slabs are installed. The highway lanes are reopened the next morning.