[_____] gallons in ten minutes shall be grouted as specified in paragraph
Waterproofing Anchor Holes, and redrilled.
][3.2.9
Waterproofing Anchor Holes
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NOTE: Where the rock is known to be fractured or
have interconnections, pregrouting of the hole prior
to watertightness testing may be required. Where
the rock in the free stressing zone is fractured and
where the anchor is installed through unconsolidated
material, a packer will be required to properly
grout the rock. Waterproof grouting of anchor holes
should only be done with a Government representative
present to avoid overruns in the amount of grout
used. When cement grout take is excessive, a
sand-cement grout should be used.
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The rock portion of anchor holes which fail the watertightness test shall
[tremie] [pressure] grouted with cement grout as specified in paragraph
Grout for Waterproofing or Backfilling Holes. [A packer shall be installed
at the top of rock.] Grouted holes shall be redrilled while the grout
strength is considerably less than that of the surrounding rock, but not
less than [24] [_] hours after grouting. [If the grout take for the hole
exceeds [ ] bags of cement, grouting with cement shall be stopped and the
hole shall be grouted with a sand-cement grout.]
]3.3
INSTALLATION OF ANCHORS
3.3.1
General
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NOTE: Demonstration test anchors should be
designated to verify the Contractor's installation
methods and design assumptions. Demonstration test
anchors should be installed and approved prior to
drilling for other anchors represented by the anchor
to facilitate changes which may be required in
anchor depth or drilling techniques. Demonstration
test anchors must be performance tested to verify
capacity. The last sentence should only be included
when verification of anchor bond length is needed
prior to installation of production anchors.
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The Contractor shall be responsible for each drilled hole until the anchor
has been installed, grouted, stressed and accepted. Holes in rock and
casings shall be cleaned by pressurized air and/or water to remove drill
cuttings and mud. [The anchors designated as demonstration test anchors
shall be installed and tested prior to drilling the bond zone for other
anchors within the area represented by the demonstration test anchor.]
3.3.2
Placing
All the equipment used in handling and placing the anchors shall be such
that it does not damage or deteriorate the prestressing steel, corrosion
protection, or the anchorages. Each anchor shall be inspected prior to
insertion into the hole. Any damage to corrosion protection shall be
SECTION 02490
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