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.