01593290

Component

An innovative process was developed to accelerate slab replacement in concrete pavement rehabilitation projects with the goal of increasing production and reducing construction time. The process involves the use a system of temporary and reusable precast panels, and self-consolidating concrete (SCC) mix. The work consisted of laboratory tests to develop and validate the SCC mix, precast panel design and construction, and field demonstration in a dedicated test track to validate the process. In developing the SCC mix, two requirements were considered, high early strength to meet lane-opening requirement of the Florida Department of Transportation, and high slump flow that would be retained for an extended period. The SCC mix incorporated grade 57 coarse aggregate, Type I/II cement, low water to cement ratio (w/c) as well as a combination of admixtures to increase and maintain workability, and accelerate early strength development. Two 6’ x 12’ x 8” (1.83 m x 3.65 m x 0.20 m) precast panels were designed for multiple temporary installations in slab replacement pits. The panels had double reinforcing mats, lift anchors, recessed stripes along the bottom surface for added friction and grip, as well as a backer rod around the perimeter to ease panel installations and absorb any impact with the surroundings. A 400 ft. (122 m) test track was used to demonstrate the process. Inside the test track a 12.25’ x 12.25’ x 8” (3.73 m x 3.73 m x 0.20 m) slab-replacement test-pit was prepared and used to evaluate the installation and removal of the panels, as well as the casting of the replacement slab using the SCC mix batched in a concrete plant and delivered in a truck mixer. The precast panels and replacement slab were tested under multiple cycles of heavy trucks without experiencing panel failure or cracking in the replacement slab. The process was validated for speed of panel installation/removal and SCC casting, retention of SCC workability and development of high early concrete strength

This paper was sponsored by TRB committee AFH50 Standing Committee on Portland Cement Concrete Pavement Construction.

01584066

16-6421

English

24p

2016

Transportation Research Board 95th Annual Meeting

Digital/other

Figures; Photos; References; Tables

Concrete pavements; Panels; Precast concrete; Rehabilitation; Self compacting concrete; Slabs; Test tracks

High early strength concrete; Replacement (Structural components)

Florida

Highways; Maintenance and Preservation; Materials; Pavements

Transportation Research Board Annual Meeting 2016 Paper #16-6421

TRIS, TRB, ATRI

Jan 12 2016 6:51PM