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COMMERCE BUSINESS DAILY ISSUE OF MARCH 18,1996 PSA#1553BUREAU OF RECLAMATION, ACQUISITION OPERATIONS GROUP, D7810 DFC PO BOX
25007, DENVER, CO 80225-0007 C -- REMOVE AND SHIP FOUR,INTACT, FULL THICKNESS PRESTRESSED CONCRETE
PIPE WALL SAMPLES SOL 142596RQ8100057 DUE 042596 POC Purchasing Agent,
EVELYN M TATE, 303-236-8040, X228 Concerns having the ability to remove
and ship four intact, full-thickness, Hayden-Rhodes Aqueduct
prestressed concrete pipe wall samples (about 3-feet circumferential by
1-foot longitudinal by 2-feet thick) from at least four pipes exposed
on two previously excavated sites located on the New River Arizona
Project, near Phoenix, AZ are requested to give written notification,
including a telephone number for a POC to the acquisition office listed
in this notice within 30 calendar days from the date of synopsis. The
Bureau of Reclamation, requires a Contractor for removal of at least
fou intact, full-thickness, Hayden-Rhodes Aqueduct (HRA) prestressed
concrete pipe wall samples. Full-thickness samples must be externally
acquired through thick pipe walls sequentially consisting of mortar
(about 3/4-inch thick), steel wire (about 1/4-inch in diameter, spaced
every 1/4-inch), concrete (about 2-feet thick) and possibly a steel
cylinder (about 1/16-inch thick). Excavation of the 252-inch diameter
pipes will be performed by Reclamation prior to sampling; internal
access through the siphons will not be permitted unless permission is
granted on an emergency basis by Reclamation in accordance with
Reclamation construction safety standards. At each excavation site,
excavations will be performed to the joint of the two pipe units to be
exposed. Thereafter, about one-third of each pipe (each 22-feet long)
will be exposed from the joint in the longitudinal direction.
Additionally, about two feet right of the crown and four feet left of
the crown will be exposed circumferentially. Full-thickness samples
must be acquired which preserve the in situ environment about each
wire's periphery inclusive of the bond to the mortar and concrete core;
thus the cut wire must be externally and mechanically restrained from
moving off of the concrete pipe core. Thereafter, the exposed surfaces
of the sampled areas must each be covered and secured with a plate
that is of sufficient thickness and strength to resist at least 25 feet
of earth overburden. The plates must be fastened in place. If the
plates and fasteners are comprised of ferrous components they must be
completely coated with a Reclamation-approved corrosion-resistant
material. The acquired samples must be shipped by the contractor, using
a contractor-supplied method that will preserve intact sample
integrity, to the Engineering and Research Laboratory, Building 56, in
Denver, Colorado where they will be subsequently prepared by
Reclamation for microscopic analysis. Samples must be acquired and
delivered by May 3, 1996. Previous Reclamation experiments have
indicated that if a prestressing wire is cut externally through the
mortar coating, full wire stress will be established at a
circumferential distance of about 18 to 24 inches from the initial cut
via expansion and anchoring of the wire into the mortar coating as
well as frictional restraint. Thus, circumferential sample lengths of
about 3-feet minimum are required to obtain a preserved wire
environment representative of in situ conditions at sample center with
no external restraints. When external mechanical restraints are
applied, they serve to further compress the wire against the concrete
core thereby preventing less of it from becoming totally
stress-relieved and preserving more of an intact, representative sample
over the 3-foot circumferential length. Contractor-supplied mechanical
restraints covering an external surface area of 3-feet circumferential
by 1-foot longitudinal minimum, are therefore required (1) during
sample removal to hold the wires in place thereby providing a large
preserved area representative of in situ conditions towards the sample
center and (2) after sample removal to provide a means of gradual
stress-relief of the prestressing wire towards the sample center as
mechanical restraints are subsequently and systematically removed from
the ends by Reclamation to facilitate additional sample modifications.
On thinner-walled pipes, the mortar-wire-concrete interface has been
successfully preserved by use of metal banding straps that were
inserted through circumferential cuts and tightened around the sample
prior to cutting of the prestressing wire and complete sample removal.
The procedure allowed for gradual stress-relief of the wire and an
intact, preserved specimen toward the center as banding straps were
subsequently removed from the ends. After additional Reclamation
cutting and applications of epoxy, a thin section representative of the
in situ wire environment, about the size of a microscope slide, was and
will be ultimately produced for the purposes of petrographic analysis.
The removal of samples from large diameter pipe necessitates the use
of contractor-supplied specialized equipment, namely a wire saw, which
provides the only known practical means of acquiring specimens from
thick-walled structures. Associated equipment, materials and services
likely to be required: (1) to initially core through the pipe walls to
allow for positioning of a specialized wire saw into the pipe interior
from the pipe exterior. (2) to provide for at least 3-feet
circumferential by 1-foot longitudinal mechanical restraint over the
external pipe surface to prevent the prestressing wire to be cut from
lifting off of the concrete pipe core (i.e. perhaps by use of
mechanical restraints such as bolts, angle irons,steel plates or a
combination thereof). (3) to saw through the reinforcing wire (i.e
probably by circular saws) as well as chip concrete and mortar (i.e.
likely with pneumatic hammers) to provide a path or guide for the wire
saw. (4) to support the heavy (about 900 pound), full-thickness sample
during cutting and removal. (5) to support and transport the removed
specimens in intact and preserved form to the Reclamation laboratory in
Denver, Colorado (i.e. likely by pallets, steel bands via truck). (6)
to cover and secure all exposed surfaces of the sampled areas with
plates that are of sufficient thickness and strength to resist at least
25 feet of earth overburden. The plates must be fastened in place (i.e.
likely with bolts). If the plates and fasteners are comprised of
ferrous components they must be completely coated with a
Reclamation-approved dielectric material (i.e.epoxy or moisture cured
urethane). (therefore, 7) to provide a safe working environment in
compliance with Reclamation construction safety standards. Electricity,
compressed air and water will not be available at the excavation sites;
thus self-contained, contractor-provided equipment (i.e. generators,
compressors, water storage containers) will be required for the
operation of contractor-supplied equipment (i.e. saws, pneumatic
hammers). Water is available to the contractor a few miles from the
sampling sites; however, it must be pumped out of canals, stored and
transported to the excavation sites by the contractor for
accessibility. Reclamation believes that only DeAndrea Coring and
Sawing Inc., possesses the unique knowledge, equipment (along with the
associated skills/capabilities necessary to operate this equipment)
and capabilities that are required for obtaining prestressed concrete
pipe samples in an intact and preserved form such that they may be
further modified and studied in sufficient microscopic detail by
Reclamation. The removal of samples from 252-inch diameter pipe, the
largest circular prestressed structures ever built, necessitates the
use of a wire saw, which provides the only known practical means of
acquiring specimens from thick-walled structures. Samples must be
acquired by the beginning of May 1996. This is not a formal
solicitation. Firms that respond shall provide detailed data concerning
their capabilities to meet this requirement. Firms may request to
receive a copy of the solicitation when and if it becomes available.
This notice may represent the only official notice of such a
solicitation. All sources responding to this synopsis shall submit
information relating to business status, including identification as to
whether they are small, large, minority-owned, and/or woman-owned. The
small business size standard for this acquisition is $2.5 Million
average annual receipts over the past three years. See Note 22. (0074) Loren Data Corp. http://www.ld.com (SYN# 0022 19960315\C-0001.SOL)
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