liquid form.
b. Cement, or preblended cement and fluidifier, if the fluidifier is
in a powder form.
c.
Remaining ingredients.
3.3.5.2
Mixing Time
The mixing time for each batch, after all solids are in the mixer, shall be
not less than 2 minutes. The mixer shall be provided with an acceptable
device to lock the discharge mechanism until the required mixing time has
elapsed. Mixer shall not be charged in excess of the capacity recommended
by the manufacturer nor shall they be operated at a speed in excess of the
manufacturer's recommendation.
3.2.5.3
Pumping Procedure
Before starting to mix and pump grout, disconnect the grout hoses from
inserts or from inlet points and flush the lines with water. Excess water
shall be cleared from the pumps and lines. At the start of grouting, with
the grout delivery lines disconnected at the inserts, grout shall be pumped
and wasted until grout exiting the line is the same uniform consistency as
that being discharged from the mixer. The coarse aggregate within the
forms shall be in a moist condition at the time of intrusion. The
intrusion shall be started at the lowest point in the aggregate. All
pumping shall be done uniformly and at the rate that will permit the grout
to fill all voids and avoid displacing the aggregate. After being
discharged into the agitator tank, each batch of grout shall be
continuously agitated until that batch is fully discharged into the pump.
Grout insert pipes shall be properly arranged and spaced to ensure a
relatively level uniform grout surface. Initially the outlet end of the
intrusion lines shall penetrate the aggregate mass to within 50 mm 2 inches
of the base of the aggregate, unless otherwise directed. The outlets shall
be raised as the grout rises, and after grouting has progressed
sufficiently to so permit, the outlets shall extend into the grout not less
than 300 mm 12 inches. Satisfactory means shall be provided for venting
the underside of embedded projections with procedures previously submitted
in accordance with paragraph SUBMITTALS. Grouting shall be continued until
grout of the specified quality is returned from the vent pipes, thereby
indicating completeness of grout injection. During the intrusion
procedure, the forms shall be externally vibrated in the vicinity of the
grout surface. Sounding wells or other approved means of accurately
locating the grout surface without interrupting the intrusion procedure
shall be provided for observation and regulation of the level of the grout.
Agitation of grout shall be continuous during any shutdown of the
intrusion procedure. When there is a lapse in the operation of intrusion
in excess of 15 minutes, the grout shall be recirculated through the pump,
or agitator and pump. The grout delivery lines shall be flushed with clean
water if they become blocked. They shall be disconnected from grout insert
pipe before the flushing operation is performed and shall not be
reconnected to grout insert pipe after flushing until pumping is resumed
and grout appears. In no case shall grout be used after appreciable
stiffening of the grout mixture has occurred. [When placed underwater,
intrusion shall begin while aggregates are being placed and shall follow
closely behind aggregate placement unless otherwise approved. At no time
shall the grout surface be brought closer than 300 mm 1 foot of the lowest
point of the aggregate lift prior to topping out.]
SECTION 03372
Page 26
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