Street and Local Roads

siennatearfulΠολεοδομικά Έργα

25 Νοε 2013 (πριν από 3 χρόνια και 9 μήνες)

70 εμφανίσεις

Street and Local Roads

Inspection and Acceptance of
Alternative Pavements

Alternatives


Pre
-
cast Concrete Pavement



Precast Concrete Pavement


Precast concrete pavement eliminates the need
for on
-
site cure time by using prefabricated
concrete panels. The panels are made at a
specialized pre
-
casting facility ahead of time, then
hauled to the construction site and installed as
needed. The result is a pavement that can be
opened to traffic almost immediately after panel
installation, without compromising the durability
and long
-
term performance of the pavement


Precast concrete has long been a proven as
durable pavement, providing 30 years of service
life or longer with minimal maintenance.


Alternatives




Continuous Concrete Pavement








Continuous Concrete Pavement


Benefits from using unreinforced concrete
slabs are lower construction cost with the
saving on mesh reinforcement and the
potential for continuous pouring.


The contraction joints of unreinforced
concrete slabs should be relatively
maintenance free.

Alternatives


Roller Compacted Concrete Pavement

Roller Compacted Concrete


Roller
-
compacted concrete, or RCC, takes its name from the
construction method used to build it. It's placed with conventional or
high
-
density asphalt paving equipment, then compacted with rollers.


RCC has the same basic ingredient as conventional concrete: cement,
water, and aggregates, such as gravel or crushed stone.


But unlike conventional concrete, it's a drier mix

stiff enough to be
compacted by vibratory rollers. Typically, RCC is constructed without
joints. It needs neither forms nor finishing, nor does it contain dowels or
steel reinforcing.


Withstands extremely heavy loads, no rutting.


Will not deteriorate from spills of fuel or hydraulic leaks.


Will not soften when exposed to high temperatures.


Open to traffic quickly.


No special equipment needed.


These characteristics make RCC simple, fast, and economical.





Continuously Reinforced Concrete
Pavement


Continuously Reinforced Concrete
Pavement


Type of Portland cement concrete pavement
reinforced with steel re
-
bars throughout its length


The use of continuous reinforcement generates
the random cracks in the pavement, while
obviating the need for transverse contraction joints
that appear prone to joint
-
related distresses and
failures. The cracks can be held tightly by the
reinforcement and should be of no concern so
long as they are uniformly spaced, maintaining the
structural integrity of the pavement.


The elimination of transverse contraction joints
can offer high riding quality

Inspections


Pre
-
Construction Meeting




Permits


Maintenance of Traffic


Lane closures/detours


Progress schedule


Required Transmittals



Pavement design



Source of Materials


Required inspections and
testing

Inspections and Testing


SUBGRADE


Proof roll subgrade


Undercut any unsuitable or
failing areas/stabilize
materials (if required)


Backfill of undercut area
with approved materials


Perform appropriate
moisture and density
testing


Verify approved typical
section.




Inspections and Testing



SUB
-
BASE


Proof roll


Remove/correct any
undulating areas


Perform appropriate
moisture and density
tests


Verify approved typical
section


Verify stone depths


Inspections and Testing


FORM WORK


(if required)


Ensure forms are clean
and oiled


Ensure flanges are not
bent


Ensure forms are
sufficiently braced


Check vertical and
horizontal alignment of all
forms


Perform depth checks

Inspections





CONCRETE PLACEMENT



Prior to placement ensure
appropriate expansion joints


Testing for slump and air


Rate:


Make control/lab cylinders


Ensure concrete is cured
properly and in accordance with
approved method.


Verify temperatures, dispatch
times, cold joints


Inspections and Testing



FINAL INSPECTIONS



Ensure all forms are removed


Verify all laboratory cylinder
breaks are in compliance


Verify line and grade.


Straight edge joints for
compliance


Perform an overall visual
inspection of the pavement
surface condition, condition of
joint material etc