Title: Engineering a better road: Use of two-way prestressed, precast concrete pavement for rapid rehabilitation
Date: Winter, 2013
Page number: 129-141
Author(s): Tinu Mishra, Phil French, and Ziad Sakkal
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The need for rapid, durable roadway rehabilitation
strategies is one of the key aspects of today’s aging
highway system. Current work windows for road construction crews are sometimes as short as four to five
hours. In these short work windows, state transportation agencies are required to maintain highways
to endure the constant wear and tear from high traffic
volumes and differing weather conditions.
The California Department of Transportation (Caltrans) rehabilitates concrete pavement exhibiting
moderate distress using rapid-strength concrete. Rapid-
strength concrete is used with or without dowels for
load transfer, depending on the contiguous length of
repair. The inadequacy of this approach led Caltrans to
pursue a more effective means of repairing the deteriorating highway system.
After years of conventional rapid-strength concrete
rehabilitation, two-way pretensioned precast concrete
pavement was used to rehabilitate a highway in the
San Francisco Bay Area. The project incorporates
a combination of jointed precast, pretensioned concrete pavement and precast, posttensioned concrete
pavement on a large scale and is nearing completion.
Differences from other precast concrete projects in the
United States are two-way prestressing (longitudinal
and transverse directions), eliminating blockout pockets through the use of end stressing, reducing the number of post-tensioning ducts, and casting and deploying
panels ranging in length from 18 to 36 ft (5.5 to 11 m).
This paper discusses the challenges encountered
during construction. In addition, this paper discusses
innovations developed to addresses various issues
encountered during construction.
1. State of California Department of Transportation (Caltrans). 2006. Maintenance and Technical Advisory Guide-Rigid Pavements. Sacramento, CA: Caltrans.
2. Caltrans. 2004. Slab Replacement Guidelines. Sacramento, CA: Caltrans.
3. Caltrans 2006 Standard Specifications. Sacramento, CA: Caltrans.
4. Merritt, David K., and Shiraz D. Tayabji. 2009. Precast Prestressed Concrete Pavement for Reconstruction and Rehabilitation of Existing Pavements. FHWA-HIF-09-008. Washington, DC: Federal Highway Administration.