ITEM 608 WALKS, CURB RAMPS, AND STEPS
608.01
Description
608.02
Materials
608.03 Concrete
Walks
608.04 Asphalt
Concrete Walks
608.05 Crushed
Aggregate Walks
608.06 Concrete
Steps
608.07 Curb
Ramps
608.08 Method
of Measurement
608.09 Basis of
Payment
608.01 Description. This work consists of
constructing walks, curb ramps, and steps.
608.02 Materials. Furnish materials conforming to:
Aggregate Base.....................................
304.01 and 304.02
Asphalt concrete Type
1............................................... 448
Concrete, Class QC Misc or QC 1* .............................. 499
Reinforcing
steel................................................. 509.02
Crushed aggregate meeting
grading requirements of........ 703.10
Expansion joint
material........................................... 705.03
* Replacing Coarse aggregate in the concrete mixes with Recycled
Concrete Aggregate conforming to Supplement
1117 is an option
608.03 Concrete Walks. Construct concrete walks
as follows:
A. Excavation. Excavate
to the required depth and to a width that allows installation and bracing of
forms. Shape and uniformly compact the subgrade to a surface conforming
to the plans.
B. Forms. Use
either fixed forms or slip-form methods. For fixed-form construction, use
wooden or metal forms that extend the full depth of the concrete and that do
not spring under the concrete pressure. For slip-form construction,
perform the work according to 609.04.C.
C. Placing and
Finishing.
Immediately before placing concrete, thoroughly moisten the subgrade.
Deposit concrete in a single layer, strike it off with a template, and smooth
it with a float to obtain a sandy texture. Do not plaster the
concrete. Use a 1/4-inch (6 mm) radius edging tool to edge all outside
edges and joints. Divide the surface of the walks into equally spaced
rectangular blocks at approximately 5-foot (1.5 m) intervals. Saw or form
transverse joints to a depth of not less than one-fourth the thickness of the
slab and to a width of approximately 1/8 inch (3 mm). Install 1/2-inch
(13 mm) thick expansion joint filler between the walk and any fixed structure
that extends the full depth of the walk. Install 1-inch (25 mm) thick
expansion joint filler between the walk and the back of curb that is on a
250-foot (75 m) or smaller radius, such as at street intersections.
D. Slope. Construct the
surface of the walk with a transverse slope rate of 0.02 and with the low side
adjacent to the roadway.
E. Curing. Cure
concrete according to Item 451.
608.04 Asphalt Concrete Walks. Construct
asphalt concrete walks as follows:
A. Excavation
and Forms.
Excavate and construct forms according to 608.03.A
and 608.03.B.
B. Base. Place and thoroughly compact aggregate base in layers not exceeding
4 inches (100 mm) in depth.
C. Asphalt
Placement and Compaction. Place asphalt concrete in one or more
courses to provide the required depth when compacted
using a hand roller or power roller of a type and weight acceptable to the
Engineer.
608.05 Crushed Aggregate Walks.
Construct crushed aggregate walks as follows:
A. Excavation. Excavate according to 608.03.A.
B. Forms. Construct forms of wood or metal of acceptable
rigidity and to the depth of the necessary loose material. Back forms
with compacted soil to the height of the completed walk.
608.06 Concrete Steps. Construct concrete steps
as follows:
A. Excavation and Forms. Excavate and construct forms according to 608.03.A and 608.03.B.
B. Placement and Finishing. Place and finish concrete according to Item 511, except finish the treads of steps to produce a
sandy texture.
C. Slope. Slope step treads at a rate of 0.01 and toward
the next lower step.
D. Curing. Cure steps according to 608.03.E.
E. Railing. If specified, install hand railing according to
Item 517.
608.07 Curb Ramps. Excavate, form, place, finish,
and cure according to 608.03.A, 608.03.B, 608.03.C,
and 608.03.E. Finish ramps to a rougher
final surface texture than the adjacent walk and with striations transverse to
the ramp slope using a coarse broom or other method approved by the Engineer.
608.08 Method of Measurement. The
Department will measure Concrete Walk, Asphalt Concrete Walk, and Aggregate
Walk by the number of square feet (square meters) of finished surface, complete
in place.
The
Department will measure curb ramps by the number of square feet (square meters)
completed. The Department will measure detectable warnings in existing
curb ramps and at grade crossings by the number of square feet (square meters)
completed.
The
Department will measure Concrete Steps by the number of feet (meters), along
the front edge of each tread. Where steps are constructed with integral
walls, the Department will include the thickness of the integral walls with the
tread width measurement.
608.09 Basis of Payment. Payment for walks, curb
ramps, detectable warnings, and steps is full compensation for excavation,
backfill, concrete cutting/sawing, base course material, reinforcing steel,
hand railing, expansion joint materials, and any incidentals required to complete
the installation as specified. The Department will pay for accepted quantities
at the contract prices as follows:
Item
Unit
Description
608
Square
Foot
Concrete Walk
(Square Meter)
608
Square
Foot
Asphalt Concrete Walk
(Square Meter)
608
Square
Foot
Aggregate Walk
(Square Meter)
608
Square
Foot
Curb Ramp
(Square Meter)
608
Square
Foot
Detectable Warning
(Square Meter)
608
Foot
(Meter)
Concrete Steps