3.1.2.5
Grout Pump
The grout pump shall operate by positive displacement or progressive
cavity. The pump shall be equipped with a by-pass line connecting the
discharge and inlet or provide circulation into the agitator for continuous
operation if line blockage or temporary shutdown of grouting operation
occurs. A pressure gauge shall be installed on the pump discharge line to
indicate incipient line blockage or a plugged insert pipe. Standby pumping
equipment shall be provided.
3.1.3
Grout Pipe System
3.1.3.1
Delivery Pipes
The main delivery line carrying grout from the grout pump to the vicinity
of the insert pipes shall be of such diameters that grout velocity at the
planned operating rate will range between 0.6 and 1.2 meters 2 and 4 feet
per second. All pipe fittings shall be watertight. Unions shall be
provided for quick disconnect to facilitate pipe cleanup when required. A
manifold system in which more than one grout insert is operative at the
same time will not be permitted.
3.1.3.2
Grout Insert Pipes
The pipes shall be [19] [25] [40] mm [3/4] [1] [1-1/2] inch in diameter
conforming to ASME B36.10M Schedule 40. Standard pipe couplings may be
used if the couplings are to be withdrawn not more than 4.5 m 15 feet
through the preplaced aggregate. Where pipe couplings are required for
greater depths of preplaced aggregate, flush-coupled pipe conforming to
ASME B36.10M Schedule 160 shall be used. Connections between grout
delivery hoses and insert pipes shall be by means of quick-opening
fittings. Quick-disconnect pneumatic fittings will not be permitted for
this purpose. All valves in the pipe system shall be plug or ball type,
quick-opening, and which can be easily taken apart and cleaned. Valves
over 25 mm 1 inch in diameter shall be stem lubricated.
3.1.3.3
Sounding Wells
The sounding wells shall be 50 mm 2 inch diameter steel pipe provided with
milled (not burned) 13 mm 1/2-inch open slots 150 mm 6 inches long with 300
mm 12 inches between slots. The pipe shall be reamed and burrs removed
before installation. The sounding line shall be equipped with a 25 mm 1
inch diameter float having a mass so as to sink in water, yet float on the
grout surface within the slotted pipe.
3.2
PREPARATION FOR PLACEMENT
3.2.1
Embedded Items
Before placement of coarse aggregate for preplaced-aggregate concrete, care
shall be taken to determine that all embedded items are firmly and securely
fastened in place as indicated on the drawings, or required. Embedded
items shall be free of oil and other foreign matter such as loose coatings
or rust, paint, and scale. The embedding of wood in concrete will be
permitted only when specifically authorized or directed. Voids in sleeves,
inserts, and anchor slots shall be filled temporarily with readily
removable materials to prevent the entry of grout into voids. Welding,
including tack welding, will not be permitted on embedded metals within 600
mm 2 feet of the surface of the preplaced-aggregate concrete.
SECTION 03372
Page 22
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