2.4.1.3
Hydraulic Power Unit Enclosure
A NEMA Type 3R enclosure as specified in NEMA 250 shall be provided to
enclose the hydraulic power unit. The enclosure shall be designed for easy
removal of the hydraulic power unit components and other accessories
without complete removal of the enclosure. An access door with hinges and
an inside and outside operable/lockable exterior door latch shall be
provided. Equipment within the enclosure shall be placed and configured so
that all periodic maintenance can be performed through the access door
without removal of the equipment. The enclosure shall be equipped with
weatherproof louver vents appropriately sized and located to dissipate
internal heat generation.
2.4.2
Manual Crash Beam
The crash beam shall be manually raised and lowered with the aid of a
counterbalanced end requiring approximately 267 N 60 pounds of force.
2.5
PORTABLE RETRACTABLE BARRIER
The portable retractable barrier shall be transportable and capable of
manual and/or electro-mechanical operation. When in the raised position,
the total barrier heights shall be no less than [_____] mm inches above
the roadway surface and shall be [_____] mm inches wide. The barrier
shall be equipped with entrance/exit ramps when the barrier extends more
than 16 mm 5/8 inch above the roadway surface. Retractable barriers in the
lowered position shall be capable of supporting a 142 kN 32,000 pound axle
load or a 71 kN 16,000 pound wheel load. Design for this load shall be
accordance with AASHTO HB-17.
2.5.1
Powered Portable Retractable Barrier
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NOTE: Based on peak hourly volumes, fill in number
of cycles per hour that the barrier will be required
to function (maximum 300 complete up/down cycles per
hour).
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The portable retractable barrier shall be capable of [_____] complete
up/down cycles per hour. The retractable barrier motion shall be instantly
reversible and shall be capable of raising the barrier from the lowered
position to the raised position within 8 seconds during normal use, and
within 2 seconds during an emergency. Also, the barrier shall be capable
of being closed from the raised position to the lowered position in not
more than 3 seconds. [Retractable barrier shall withstand a [_____] kg
pound vehicle at impact speed of [_____] km/hour mph with maximum barrier
deflection or vehicle penetration of [_____] m feet.] Portable
retractable barrier, when impacted by a [_____] kg pound vehicle at impact
speed of [_____] km/hour mph shall disable the vehicle and allow it to
travel no more than 15.2 m 50 feet after impact. Portable power assisted
retractable barriers shall be equipped with on and off ramps for smooth
transition between surfaces when the barrier extends more than 16 mm 5/8
inch above the roadway surface.
2.5.1.1
Failure Modes of Operation
The system shall be designed to prevent lowering of the barrier in the
event of hydraulic, electric, or mechanical failure. A manual pump shall
SECTION 02840
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