Compatible Devices and Products
Infiltrator tanks are compatible with the following products for buoyancy
control:
• Tie-down straps: high-tensile-strength, 10,000 lb (4,500 kg) minimum
capacity, nylon or polyester, with corrosion-resistant hardware.
• Concrete deadmen anchors: concrete-filled plastic half pipe, precast
parking bumper, precast traffic barrier, or precast block.
• Helical anchors: Chance™ No-Wrench Screw Anchors with minimum
6-inch (150 mm) diameter, Class 7 or equal.
• Mid-Seam Concrete Collar: cast-in-place concrete (minimum 3,000 psi
compressive strength at 28 days and minimum 6% air entrainment).
Tie-Down Straps
Straps are commercially available in varying
lengths and with assorted hardware and
tightening options. Nylon or polyester
strapping with minimum 10,000 lb (4,500 kg)
capacity is required for buoyancy control use
with Infiltrator tanks. Place straps over the tank at specified locations only
(see Figure 5). Tighten straps snugly with a ratchet or turnbuckle system to
remove all slack and slightly pre-load the system. All connections, fittings,
and hardware must be corrosion resistant or coated with epoxy or other
corrosion-resistant materials to inhibit deterioration in the subsurface
environment. Consider encapsulating such components in heat-shrink
tubing or applying a corrosion-resistant coating prior to burial.
Concrete Deadmen Anchors
Recommended concrete deadmen anchors include filled plastic half pipe,
precast parking bumpers and traffic barriers, and precast blocks. The
weight of the deadmen anchors combined with the weight of soil above
them provides buoyancy control when properly secured. Deadmen anchors
are placed at the bottom of the tank excavation on opposite sides of the
tank. The deadmen anchors are fastened to each other with tie-down
straps placed over the tank at the locations specified for each tank model
(see Figure 5).
Concrete-filled Plastic Half Pipe
Use Schedule 40 PVC plastic pipe with a minimum
inside diameter of 15 inches (375 mm) or HDPE
corrugated pipe with a minimum inside diameter of
18 inches (450 mm) cut in half lengthwise. Fill with
concrete having a minimum unit weight of 145 lbs/ft
3
(2.32 metric tons/m
3
) reinforced with three equally
spaced 40-grade,
1/2-inch (13 mm) diameter steel bars. Weight is 61
lbs/ft (91 kg/m) minimum.
Concrete Parking Bumper
Use commercially available steel-reinforced
parking bumpers with typical dimensions of 12
inches wide by 6 inches high (300 mm x 150 mm).
Weight is 58 lbs/foot (86 kg/m) minimum.
Concrete Traffic Barrier
Use commercially available steel-reinforced concrete traffic barrier or
equivalent. Typical dimensions include a
24-inch-wide base tapering to a 6-inch-
wide top, with a height of approximately
32 inches (600 mm x 150 mm x 800 mm).
Weight is 390 lbs/foot (580 kg/m) minimum.
Precast Blocks
Concrete precasters can fabricate blocks
of various dimensions and weights. Blocks
are often an affordable option if they satisfy
the minimum weight requirements for use
as buoyancy control (see Table 2 and the
Supplemental Force section of Step 2 for
more information).
Helical Anchors
Chance™ No-Wrench Screw Anchors with a
6-inch (150 mm) diameter flight, Class 7, or
equal. These anchors rely on the shear strength
of the soil combined with the weight of the
soil above the anchor flight to provide holding
strength. Proper installation is to 4 feet (1.2 m)
below the bottom of the tank excavation and to
within 5° of alignment with the strap alignment.
Determine the proper locations for anchor
installation to ensure that tie-down straps will
be aligned properly for each tank model (see
Step 3: Implementation), and follow the anchor
manufacturer installation instructions.
Concrete Collar
A ballast may be constructed along the mid-
height seam of the tank using cast-in-place concrete (minimum 3,000
psi compressive strength at 28 days and minimum 6% air entrainment).
Concrete shall be cast in contact with the exterior surface of the tank to
allow interlock with sidewall ribs and the mid-height flange. Reinforcing
steel is not required, but may be added if desired.
Step 3 – Implementation
Effective buoyancy control of Infiltrator tanks requires careful preparation,
thorough excavation, precise placement, secure strapping and proper
backfilling, as described and illustrated below.
Excavation Requirements
It is recommended that the excavation width provide a minimum of 36
inches (900 mm) clearance beyond the tank on all sides when utilizing
buoyancy control. This will allow sufficient space within the excavation to
place anchoring equipment and fasten strapping. The excavation should
provide a minimum 48-inch (1,200 mm) clearance beyond the tank when
using Chance™ No-Wrench Screw Anchors to allow for room to properly
install the screw anchors. The actual excavation size shall be determined by
the installer. Refer to Infiltrator IM-Series Tank Installation Instructions for
additional excavation procedures.
Concrete-filled Half Pipe Construction
Concrete-filled half pipe shall be supported with soil or other stabilizing
means below the pipe haunches prior to concrete placement. The
stabilization shall prevent the pipe from rolling during placement and curing
of the concrete. Concrete shall be allowed to cure for a minimum of one
day prior to tank backfilling.
Placement of Deadmen and Anchors
Concrete deadman anchors are to be installed at the bottom of the tank
excavation, parallel to the long axis of the tank (see Figure 3).
Figure 3: Plan View
The deadmen should be placed close to, but not touching, the tank on both
sides of the tank to allow the placement of backfill between the deadman
anchor and tank sidewall (see Figure 4).
18 in
[450mm]
12 in
[300 mm]
6 in
[150 mm]
24 in
[600 mm]
32 in
[800 mm]
Quick4 Plus Equalizer 36 LP
Typical working torque:
¾” Rod 400 ft. lbs. (542 N
•
m)
1” Rod 1,000 ft. lbs. (1,356 N
•
m)
1¼” Rod 2,300 ft. lbs. (3,118 N
•
m)
15 in [375 mm] to
18 in [450 mm]
Steel Rebar
18 in
[450mm]
12 in
[300 mm]
6 in
[150 mm]
24 in
[600 mm]
32 in
[800 mm]
Quick4 Plus Equalizer 36 LP
STRAPPING
DEADMAN
ANCHOR
(TYPICAL)
STRAP
WIDTH
6" (150 mm)
MIN EXTENSION
6" (150 mm)
MIN EXTENSION
Contact Infiltrator Water Technologies’ Technical Services Department for assistance at 1-800-221-4436.
