This work consists of furnishing and placing Portland cement concrete barrier on the accepted and prepared subgrade, subbase course, or existing pavement. This item consists of furnishing, placing, maintaining, and removing portable concrete barrier.
The concrete barrier will be constructed by either cast-in-place, precast, or slip-form methods. For slip-form construction, conform to 609.04.C. For cast-in-place construction, conform to the proper SCD.
1. RM- 4.3 Single Slope Barriers.
2. RM- 4.4 Single Slope Barrier Transitions.
3. RM- 4.5 Single Slope Barrier, Type D.
4. RM- 4.6 Concrete Barrier End Sections.
The individual sections of PCB shall be no less than 10 feet (3 m) long. See SCD RM- 4.2, 32-inch Portable Concrete Barriers for details. If intending to use the barrier at one location on the project, the Contractor may slip-form barriers in place without joints or with grooved or sawed joints to facilitate removal. Any barrier sections damaged during handling or by traffic shall be either repaired or replaced for the life of the project.
The joints for cast-in-place or slip-formed barriers shall be constructed of the type and dimensions and at the locations specified in the plans.
The Contractor may construct unsealed contraction joints by sawing using metal inserts inside the forms, using a grooving tool, or using full-width, 3/4 inch (19 mm) thick, preformed joint filler conforming to 705.03. Joints shall be sawed, tooled, or formed by inserts a minimum of 1/8 inch (3 mm) wide and 3 inches (75 mm) deep. The joints should be sawed to the required depth with minimal spalling of the concrete surface as soon as curing allows.
The 3/4-inch (19 mm) thick, preformed joint filler shall conform to 705.03 to construct expansion joints.
If, and as shown on the plans, the Contractor may place horizontal construction joints.
Check the surface of the barrier with a straightedge for irregularities of more than 1/4 inch in 10 feet (6 mm in 3 m) after the Contractor has checked and made corrections. Document any findings on CA-D-3.
Concrete curing shall be according to 511.17, Method B, and the following additional requirements. Ensure that the curing compound is approved. For small areas, allow the use of other acceptable methods.
Do not allow any load or any work that will damage newly placed concrete. A minimum of 36 hours of cure time is required on any concrete placed first at a horizontal construction joint. The Contractor may cure precast sections according to 515.15. The Contractor may use radiant heated forms for curing.
The Contractor may use 511.17, Method A for curing of short sections of barrier (leave-outs); however, before the curing is completed for any leave-outs, material conforming to 705.07, Type 2 at the normal rate specified in 511.17, Method B shall be applied.
The Contractor may cure horizontal construction joints between the foundation and the upper portion of the barrier, and between portions of the upper barrier placed separately according to 511.17, Method A or B. The membrane should not be removed before placing the next portion of the concrete barrier.
Measure concrete barrier by the number of feet (meters) along the centerline of the top of the barrier, including all transitions, end terminals, and bridge pier sections as specified, complete in place.
Measure portable concrete barrier and portable concrete barrier, bridge mounted by the number of feet (meters) for each application of the barrier placed according to the plans. Measure each re-use of barrier sections at a different location required by the plans separately.
Do not measure repaired or replacement barrier sections which are damaged during handling or by traffic.
The cost of all inserts, sleeves, fittings, connectors, reinforcement, dowels, preformed filler, excavation, and backfill is incidental to these items.
1. Form dimensions.
2. Conform to section 609.04C if slip formed.
3. Number and clearance maintained on reinforcing steel if any used.
4. Joint spacing and thickness of expansion material used.
5. Joints saw cut, formed with metal plates, or expansion material
6. Amount of curing compound required and used.
7. Measure length for pay.
8. Use form CA-D-3 for documentation.