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General
Furnish all labor, equipment,
and materials necessary and incidental thereto to perform all required
operations to eliminate the flow of water by pressure injection
to fill cracks, voids, and joints in concrete substrates.
Definition of Terms
Refusal when a crack or void
area will accept no more grout under the prevailing pumping conditions
(for reasons other than the pumpability of the grout)
Return time the time taken
for a grout, under certain application conditions to completely
penetrate a crack, void, or network of cracks.
Gel time the time required
for the grout to cure following the reaction with the accelerator.
Gel time or cure time can be affected by temperature and amount
(percentage) of accelerator mixed in the component A.
INJECTION PROCESS:
Fully examine the existing site conditions to ensure that all associated
work can be performed without removing or relocating existing utilities,
structures or structural members.
1) Remove all standing water.
2) Drill at a 45° degree angle where possible to intersect the
wall/floor joint interface halfway through the thickness of the
substrate (e.g. 4” deep for 8” thick slab) Drill straight
into the crack for concrete thickness below 4 inches.
3) Drilling depth should be half the thickness of the concrete member.
4) Install mechanical injection ports and secure in place at a spacing
of 6-12” inches apart (6” for hairline and 12” for
wider cracks). Alternate positioning from left side to right side
as you move along the crack where possible.
Extremely wide cracks (if
any exist) should be covered with a surface seal prior to injection
in order to contain the injection resin until cured. Under proper
pumping conditions in active leak injection, the following signs
should be observed in the order listed:
INJECTION PROCESS (Continued)
(a) Water displaced from crack/joint
by the resin
(b) Water and resin mix (foamy) appearing at the crack/joint area
(c) Pure resin from crack/joint
If the joint surface exhibits
immediate free flow of resin while working the first packer, pause
for a few minutes. In most cases the resin will react fast enough
with the water and expand rapidly. The resulting resin product will
heal the joint and provide a surface seal to contain the material
to follow.
The contractor is responsible
for estimating what duration time is adequate for grouting the voids
and is responsible to prove that the void is full by attempting
to inject each port to refusal.
Once the contractor is assured
that the resin has reached the next injection packer or has sufficiently
stopped the water as evidenced by the grout oozing out of the joint
area, he should shut off the resin flow and disconnect pump pressure
line and proceed to the next packer.
Follow the injection process
for one to three packers, the contractor shall return to the first
packer and attempt to re-inject it again. Some of the packers will
take more grout, filling up more of the crack/joint area and creating
a higher density void filler and water stop.
The contractor shall continue
this procedure until refusal.
MATERIALS
A. Injection Ports
Provide suitable injection ports (stainless steel/brass/zinc/plastic),
buttonhead or zerk fittings, shaft and rubberized expandable grommet.
B. Grout Injection Material
Hydrophobic water cut-off grout based on MDI (methylene-diphenyl-isocyanate)
polyurethane. (e.g. SealBoss 1510, 1570, 1572)
Grout material is to be 100% solvent free and 100% solids.
Gel time of the product is adjustable by adding a certain percentage
of accelerator per the manufacturer’s recommendations. Grout
material shall not shrink or swell.
Grout material shall cure to a semi-flexible foam structure which
is not affected by water or dryness.
Grout material shall have the capacity to expand upon contact with
water to a volume of 30 to 40 times. The composition of the material
is one that water is not a component of the cured foam structure.
C. Pump Equipment
All chemical grouting equipment
shall be of a type, capacity, and mechanical condition suitable
for doing the work. The equipment shall be compatible with the chemicals
to be handled and shall be maintained in proper operating conditions
at all times.
Environmental Requirements
1) Do not apply if the temperature is below 45F or above 95F unless
the material manufacturer is consulted for recommendations.
Product should always be conditioned to room temperature
Owner’s Requirements
1) Execute all work in accordance with all safety requirements,
approved written procedures and with the least amount of interference
with the work of other trades as possible.
2) Equipment should be confined to the delivery area and all components
shall be in good working order as approved manufacturer for use
with the specified materials.
3) Immediately notify the Site Engineer/Owner’s representative
in the event of any process interruption or environmental concerns
which could affect the service or application conditions relative
to this work.
Protection, Cleaning and Safety
1) Following a complete injection
of all mechanical packers to refusal and where the visible leakage
has been completely eradicated, remove all injection packers. Remove
cured material where applicable and fill injection hole with rapid
cement.
2) Clean all adjacent areas
of excess material, powder, cement and/or droppings. Chemicals used
for cleaning shall be non hazardous and non flammable such as the
SealBoss R70 pump flush
3) Process grout materials
using appropriate protective gear including gloves, masks, or goggles,
and appropriate clothing as described and in accordance with the
manufacturer’s MSDS sheets
1) Follow manufacturer’s recommendations for product safety
and disposal of material.
2) Comply with all OSHA regulations
for drilling procedures using protective gear including highlighted
vests, face shields, or goggles. Always provide for ample ventilation!
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