ITEM 622 CONCRETE BARRIER
622.01
Description
622.02
Materials
622.03 Placing
Concrete
622.04 Portable
Barrier
622.05 Joints
622.06 Finish
622.07 Curing
622.08 Method
of Measurement
622.09 Basis of
Payment
622.01 Description. This work consists of
furnishing and placing portland
cement concrete barrier on the accepted and prepared subgrade, subbase course, or existing pavement. This item also
consists of furnishing, placing, maintaining, and removing portable barrier.
622.02 Materials. Furnish materials conforming to:
Concrete,
Class QC 1 *............................................................ 499
Reinforcing steel and wire
fabric......................... 509.02
Forms
..................................................................... 515.14
Preformed filler
....................................................... 705.03
Curing
materials......................................... 705.05, 705.06,
................................................................
or 705.07 Type 2
Precast concrete
...................................................... 706.13
Dowel
bars........................................... 709.01 thru 709.05
Steel.........................................................................
711.01
* Replacing Coarse aggregate in the concrete mixes with Recycled
Concrete Aggregate conforming to Supplement
1117 is an option
622.03 Placing Concrete. Construct concrete
barrier by cast-in-place, precast, or slip-form methods. For slip-form
construction, conform to 609.04.C.
622.04 Portable Barrier. Furnish
individual sections not less than 10 feet (3 m) long. 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. As directed by the Engineer, repair or replace barrier sections
damaged during handling or by traffic, for the life of the project. The
Contractor may substitute approved proprietary portable barrier products which
can be found on the Office
of Roadway Engineering’s website.
622.05 Joints. Construct joints for cast-in-place
or slip-formed barrier of the type and dimensions and at the locations
specified.
A. Contraction Joints. The Contractor may construct unsealed contraction
joints by either 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.
Make joints that are sawed, tooled, or formed by inserts a minimum of 1/8 inch
(3 mm) wide and 3 inches (75 mm) deep. Saw joints as soon as curing
allows sawing to the required depth with minimal spalling
of the concrete surface.
B. Expansion Joints. Use 3/4-inch (19 mm) preformed joint filler
conforming to 705.03 to construct
expansion joints at locations as shown in the plans.
C. Horizontal Construction Joints. If and as shown on the plans, the Contractor
may place horizontal construction joints.
622.06 Finish. Immediately following removal of
fixed forms or slip-form construction, check the surface of the barrier with a
straightedge and correct all irregularities of more than 1/4 inch in 10 feet (6
mm in 3 m). Finish and make corrections to the barrier surface according
to 511.18.
622.07 Curing. Cure concrete according to 511.14, Method B and the following
additional requirements. Apply the curing compound using an approved
mechanical sprayer equipped with a shield to protect the spray from wind.
For small areas, the Engineer will allow the use of other acceptable methods.
Do
not apply any load or conduct any work that will damage newly placed
concrete. Allow a minimum of 36 hours of cure time to elapse on any
concrete placed first at a horizontal construction joint. The Contractor
may cure precast sections according to 515.15.
With the Engineer’s approval, the Contractor may also use radiant heated forms
for curing.
The
Contractor may use 511.14, Method A for
curing of short sections of barrier (leave-outs); however, before the curing is
completed for any leave-outs, apply material conforming to 705.07, Type 2 at the normal rate specified
in 511.14, Method B.
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 511.14,
Method A or B. Do not remove the membrane before placing the next portion
of the concrete barrier.
622.08 Method of Measurement. The
Department will measure Concrete Barrier by the number of feet (meters) along
the centerline of the top of the barrier, including all transitions, and bridge
pier sections as specified, complete in place excluding end anchorages and
excluding sections.
The
Department will measure Reinforced End Anchorages of the type specified by the
number each complete in place.
The
Department will measure End Sections of the type specified by the number each
complete in place.
The
Department will measure Portable Barrier and Portable Barrier, Bridge Mounted
by the number of feet (meters) for each application of the barrier placed
according to the plans. The Department will measure each re-use of
barrier sections at a different location required by the plans separately.
The
Department will not measure repaired or replacement
barrier sections damaged during handling or by traffic.
622.09 Basis of Payment. The cost
of all inserts, sleeves, fittings, connectors, reinforcement, dowels, preformed
filler, excavation, aggregate base, and backfill is incidental to these items.
The
Department will pay for accepted quantities at the contract prices as follows:
Item
Unit
Description
622
Foot
(Meter)
Concrete Barrier, Type ___
622
Each
Concrete Barrier End Anchorage, Reinforced, Type ___
622
Each
Concrete Barrier End Section, Type ____
622
Foot
(Meter)
Portable Barrier, ___" (___ mm)
622
Foot
(Meter)
Portable Barrier, ___" (___ mm) Bridge
Mounted