This work consists of constructing
or reconstructing guardrail, guardrail posts, bridge terminal assemblies, end
terminals, and impact attenuators, including the furnishing, assembling, and
erecting of all component parts and materials.
Guardrail shall be deep beam
rail Type 5, 5A, 8 or MGS. Appurtenances
shall include bridge terminal assemblies, end terminals, and impact
attenuators. Construction of the various
types of guardrail include the furnishing, assembling, and erecting of all
component parts and materials, complete in place at the location shown on the
plans, or as directed, and according to the manufacturer’s recommendations
where applicable.
The posts shall be set or
driven plumb in a manner that prevents battering or distorting of the
posts. The posts that are set or driven
more than 1inch above grade shall be trimmed.
The trimmed posts shall be treated with a preservative material
specified in 712.06.
The plans shall show how to
erect either a standard design (single-faced) guardrail or a barrier design
(double-faced) guardrail.
Erect rail elements in a
manner resulting in a smooth, continuous installation. Shop-curved rail shall be used on curves with
radii from 5 to 70 feet (1.5 to 22.4 m).
Do not allow straight elements to be bent or curved to fit a radius.
The bolts shall be tightened
through expansion joints, as tight as possible, to prevent the rail elements
from sliding past one another longitudinally.
Ensure that the bolts are long enough to extend at least 1/4 inch (6 mm)
beyond the nuts.
Splice bolts that extend more
than 1/2 inch (13 mm) beyond the nuts shall not be used. For double-faced guardrail, the bolts shall
extend from 1/4 inch to 1 inch (6 to 25 mm) beyond the nuts.
Do not allow burning or
welding in the field. The Engineer may
approve making holes in the field, but only for special details in exceptional
cases. The Engineer may approve field
punching, cutting, and drilling if the Contractor demonstrates that its methods
do not damage the surrounding metal.
The galvanized surfaces shall
be repaired that have been abraded such that the base metal is exposed,
including threaded portions of all fittings and fasteners and cut ends of bolts
as specified by ASTM A 780.
The guardrail shall be
erected so that the bolts at expansion joints are located at the centers of the
slotted holes. The rail elements shall
be lapped in the direction of traffic.
The plates at each splice shall make contact throughout the area of the
splice.
Unless otherwise shown on the
plans, the rebuilt guardrail shall be of the same type and spacing of members
as the existing guardrail.
The following materials shall
be new: posts, blockouts, bolts, washers, and
incidental hardware, as necessary, to complete the guardrail, except: (1) existing steel posts and blockouts that are not damaged and have a good galvanized
coating may be reused, and (2) guardrail splice bolts that are undamaged and
were not removed during salvage may be reused.
Before installation of the
attenuator, all corresponding shop drawings, installation drawings, and
instructions from the manufacturer shall be made available for the Engineer’s
inspection. Ensure the attenuator is
installed as per manufacturer’s shop drawings.
The top of each foundation
shall be graded at the same elevation as the adjacent travel lane and/or paved
shoulder. The anchors for the attenuator
shall be adjusted to avoid pavement joints.
The Department will measure
Guardrail, new or rebuilt, of the type specified, by the number of feet from
center-to-center of end posts, excluding anchor assemblies. If, however, end connections are made to
masonry or steel structures, the Department will measure to the center of the
normal post bolt slot. If rail element
is used across a bridge, the Department will measure to the first post off the
bridge.
The Department will measure
Anchor Assembly, of the type specified, by the number of each assembly
furnished and erected complete.
The Department will measure
Bridge Terminal Assembly, of the type specified, by the number of each assembly
furnished and erected complete.
The Department will measure
Impact Attenuator, of the type specified, by the number of each attenuator
furnished and erected complete.
The Department will measure
Guardrail Post, of the kind specified, by the number of each post furnished and
erected complete.
The additional costs
associated with furnishing and installing extra-length posts instead of standard-length
guardrail posts are incidental to Guardrail Post, 8 foot (2.44 m) or Guardrail
Post, 9 foot (2.75 m).
For the extra costs
associated with furnishing and installing extra-length posts in lieu of
standard-length guardrail posts, payment for 9 foot (2.75 m) guardrail posts is
considered full compensation.
Use Form CA-D-3A
to document the following items:
1. Depth post driven, post spacing.
2. All cuts and abrasions on wood post treated with
application of approved preservative.
3. Rail erected accurately to line and grade, all
hardware drawn tight.
4. Anchor assemblies and bridge terminal assemblies.
a. Number, diameter, and depth of holes drilled.
b. Top 4 inches (10 cm) of concrete anchor formed.
c. Diameter, length, and number of anchor bolts placed.
d. Number, spacing, size, and clearance maintained on
reinforcing steel.
e. Top cured.
f. Measure and pay as per 606.07.