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Page 2

OPERATIONS
Best Practices in Compressor Mounting, James A. Kuly; ITW POLYMER TECHNOLOGIES





1 Introduction
Large reciprocating compressors are found in a
number of industries including gas, oil and
petrochemical production, transmission and
storage. Operationally they generate very large gas
and inertia forces. Their mounting systems must
manage and transmit weight loads, vertical and
horizontal gas and inertia loads, vertical anchor bolt
forces, and the forces of thermal growth. The
effectiveness of the mounting system and integrity
of its installation are therefore crucial.

The purpose of the mounting system on a
reciprocating gas compressor is simple. The
mounting system must do three things:
1 Position and support the compressor, its

driver and related equipment. Hold the
compressor and driver in perfect alignment
while accommodating all of the loads applied
to it including horizontal gas and inertia loads,
weight loads, anchor bolt loads and loads due
to thermal growth and frame distortion

2 Effectively transmit the vibration produced
by dynamic forces down through the
foundation while reducing or eliminating the
harmful effects of those vibrations

3 Accomplish items #1 and #2 above for 30
years or more


While the purpose of a compressor’s mounting
system is simple, its construction is not. Reliable,
long-term reciprocating compressor operation
depends on the quality of the design and
construction of the compressor mounting system
and and the integrity its foundation. Degradation of
the foundation or loss of the mounting system’s
integrity can cause excessive frame vibration and
misalignment, and eventually crankshaft failure.


The primary problem making compressor mounting
systems difficult to design and install is vibration.
A compressor can vibrate in six different ways or
modes – three in translation (vertical, lateral,
longitudinal) and three in rotation (pitching/
yawing, torsional, rocking).


All these modes of vibration have their own natural
frequencies where resonance can occur. In
addition, one mode of vibration can be either
“coupled” or connected to other modes and drive
them. Finally, vibrations can be transmitted in
series or in parallel from one component to the
next. A well designed and constructed foundation
will not only accommodate all of the loads applied
to it including horizontal gas and inertia loads,
weight loads, anchor bolt loads and loads due to
thermal growth and frame distortion, but it will act
to reduce then effectively pass those vibrations
down to the soil below.

The complexity of analyzing and mitigating the
negative affects of vibrations in a compressor
installation is difficult and complex. The only way
to properly analyze and design a good foundation is
with the aid of such tools as Finite Element
Analysis (FEA) and foundation design programs.
In addition to these tools, there are also many
practical design and installation “rules of thumb”
that should be used. Unfortunately, many of these
are only learned through years of experience. They
are the small things that are often left off of the
installation drawings and specifications but have a
big impact on the longevity of a foundation.

This paper will focus on those “rules of thumb“
practices or techniques used in compressor
installation design and installation that directly
influence the quality of construction and integrity
of the foundation and how both of these directly
affect vibration attenuation. It will not address the
interaction of the foundation and the soil.

2 Best Practices Related to Mitigating
Vibration

To achieve a strong, high-quality yet cost-effective
installation it is important to recognize two very
important elements in the design of the mounting
system:
• The compressor and its foundation must

form a tightly integrated structure.
Vibration energy travels in the form of waves
down and out through the foundation where
the soil can absorb it. Breaks, cracks or
separations in the integrated compressor /
foundation structure will prevent the vibration
waves from traveling downward.

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OPERATIONS
Best Practices in Compressor Mounting, James A. Kuly; ITW POLYMER TECHNOLOGIES






• A compressor installation must be treated as

a series of interacting structures that move
and vibrate. Vibration energy actually
deforms the structure as it passes through the
structure. This is because the steel, grout and
concrete are all flexible. Preventing
foundation degradation and cracking means
making sure that all mounting components
work together and none act to harm the other
components or mounting system. For example,
the design and installation of the anchor bolts
should not cause the concrete to crack.


The one best word to describe what it means to
"form a tight integrated structure" is Monolithic.
A monolithic structure is one that is cast as a
massive, seamless,
uniform, and rigid
piece. The design
objective behind a
compressor installation
is therefore to create a
monolithic structure that
clamps the series of
interacting pieces
together (the
compressor and its
driver to a well
designed concrete
foundation) with
enough size and mass to
separate the dynamic response frequencies from the
excitation frequencies. This means that the mat,
concrete foundation, grout and machinery must
become one.

The following describes the best construction
practices that help reduce the impact of vibration in
the structure.

2.1. Best Practices Related To the
Construction of the Foundation


The foundation has the biggest influence on
mitigating vibration in a reciprocating compressor.
The following are best practices related to the
construction of the foundation that have to do with
reducing the impact of vibration.

2.1.1. Install the compressor and driver on a
concrete block foundation. Concrete absorbs
vibration more easily than a steel frame or skid
because its internal molecular structure absorbs
vibration energy.







2.1.2. If the compressor has to be
mounted on a skid, two best
practices are to run the anchor
bolts to the top of the skid and to
fill the void spaces inside the skid
with epoxy grout.
These practices act to stiffen the
steel.

2.1.2. Design the installation as
a rigid structure whose dynamic response will
depend only on the dynamic load, the mass of the
foundation and on soil characteristics. Make the
weight of the foundation 4 to 8 times the weight of
the compressor. The width of the foundation
should be at least 1.5 times its height.

2.1.3. Keep the center of gravity of the block and
mat within 15 to 20 cm (6 to 8 inches) of the
vertical centreline of the compressor’s crankshaft.

2.1.4. Minimize the elevation difference between
the machine’s dynamic forces and the center of
gravity of the machine-foundation system.

2.1.5. Mechanically isolate the foundation block
from any surrounding structures.

2.2. Best Practices Related to Epoxy
Grout & Chocks

The following are best practices associated with
epoxy grout and chocks.

2.2.1. A non-shrink grout is required between the
top of concrete foundation and the bottom of the
compressor and its driver so precise alignments can
be achieved. The use of epoxy grout and epoxy
chocks are, by themselves, considered a “Best
Practice” over the use of cementitious grout
because of their…
• Higher physical properties
• Superior bond strength to concrete and
steel
• Resistance to cracking
• Imperviousness to attack by oil and
chemicals

2.2.2. The best practice is to cover the
foundation with a full bed of grout then to mount
the compressor and driver on individual chocks.
The full bed of epoxy grout not only helps to
support the machinery it seals and protects the
concrete foundation. Because individual chocks are
separated by a gap, air can easily flow under and
around compressors and drivers. Chocks also allow
the recess in the foundation for the pan to be built
shallower to reduce the weakness in this area of the
block that was prone to cracking.

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Best Practices in Compressor Mounting, James A. Kuly; ITW POLYMER TECHNOLOGIES





2.2.3. Individual chocks can be either the
poured-in-place type or the pre-manufactured
adjustable type chocks. Both are good practice.
The adjustable chocks must be installed on a sole
plate while the poured-in-place type chocks can be
placed either directly on top of the grout or on sole
plates.

2.2.4. Poured-in-place chocks can be made from
either 3-component epoxy grout or 2-component
epoxy chocking compounds. The best practice
regarding which product to use is based on size of
the chock. With any single chock over 610 mm (24
inches) in length or 75 mm (3 inches) in depth it is
best to use an epoxy grout rather than a chocking
compound.

2.3. Best Practices Related to Anchor
Bolts


Anchor bolts clamp foundation and equipment
layers together. Their purpose is to prevent
movement of the equipment or separations between
the layers. Separations act as a barrier preventing
vibrations from passing completely through the
foundation to the soil.

2.3.1. To reduce vertical vibration and lessen its
impact, a best practice is to maximize anchor bolt
tension. This may seem like an obvious statement
but anchor bolt tension is often arbitrarily limited.
For example, API 686 suggests an anchor bolt
stress of only 30,000 psi (207 MPa). If this value is
used, the anchor bolt will be tightened to only 23%
of its Yield Strength. I believe that to be fully
effective an anchor bolt should be tightened to 60%
to 70% of its yield strength.

2.3.2. The static loading on the epoxy chocks or
grout should be under 6.9 MPa (1,000 psi) to
minimize creep. Static loading is made up of a
combination of deadweight loading and the loading
caused by the tensile stress on the anchor bolts.
This should be a sufficient to firmly anchor the
compressor and its driver. It also provides a 14 to
16 X Safety Factor to manage any dynamic loads
before the compressive strength of the grout is
reached.

2.3.3. Terminate the anchor bolts half way into
the mat. This combined with heavy rebar
connecting the mat to the foundation will help hold
the layers together.

2.3.4. Increase the portion of the anchor bolt that
is being stretched. The anchor bolts are essentially
springs that stretch and apply a clamping load. To
create an effective clamping force, an anchor bolt
must stretch over about 50% of its length.



2.3.5. To mitigate horizontal vibration, increase
the Coefficient of Friction (COF) of the layers. It is

the Coefficient of Friction created by the anchor
bolts that prevent sideways or lateral vibrations and
movement. Anchor bolts create the Normal Force
that, in conjunction with a high COF creates a very
high Resistive Force that absorbs the shaking force
and prevents movement. A high COF is caused by
the intimate fit of epoxy to steel because it fills
every little scratch, sandblast divot and machining
mark on the bottom of a compressor / driver.
Resistive Force is found by multiplying Normal

Force pushing down by the Coefficient of Friction.




2.4. Best Practices Related to Frame,
Rail, Sole Plate and Foundation
Preparation


Cleanliness of the compressor frame, engine rails,
sole plates or concrete foundation has always been
a best practice. There can be no oil in the concrete
and all paint, oil, grease dirt, etc. must be removed
from the frame, sole plates and rail. Cleanliness is
the best way to prevent the various surfaces from
de-bonding and from sliding due to a low COF.
The following are some additional best practices
for component preparation the will help mitigate
vibration.

2.4.1. Sand blast and clean metal frame, sole
plates or rail to SP 6. Do not prime them. Just
remove anything on the surface and give the
surface a light texture. This will increase the
COF.

2.4.2. If a primer is required on steel to prevent
it from rusting prior to installation, that primer
must be a straight epoxy primer (NO ZINC) and it
must be applied no more than 2 to 3 mills thick.

2.4.3. Chip off the surface of the concrete
foundation removing all laitance and expose 50%
chipped and broken aggregate. This will provide
a structurally solid surface to transfer vertical and
horizontal loads down through the grout and into
the concrete.

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Best Practices in Compressor Mounting, James A. Kuly; ITW POLYMER TECHNOLOGIES





3 Best Practices to Prevent Foundation
Degradation


In addition to applying Best Practices to mitigate
vertical and horizontal vibration, it is also
important to do everything possible to prevent
cracks in the foundation and the penetration of oil
and chemicals that can degrade the concrete and
allow vibrations to increase. This section contains
the best practices related to the construction of the
foundation and the installation of the machinery
related to preventing foundation degradation.

3.1. Best Practices Related To
Foundation Design & Installation

3.1.1. Concrete specification - The quality of
concrete used in the foundation is extremely
important for ensuring a long successful life of the
foundation. Best practice calls for a minimum
grade of M25 or M30 concrete. This is concrete
with a compressive strength of 25 to 30 N/mm2
(3,625 to 4,350 psi) and a tensile strength of 3.2 to
3.6 N/mm2 (464 to 522 psi). Use crushed stone in
the concrete that has angular faces. The bond of
angular faced stone to the cement paste is better
than round stone.

3.1.2. Tensile strength - A best practice is to
increase tensile strength of concrete to at least
1,000 psi using steel fibers. Steel fibers reinforce
the concrete in 3 directions. Steel fibers have a
high modulus of elasticity and high tensile
strength to withstand excess strain and prevent
cracking. Because the modulus of elasticity of the
fiber is higher than the matrix (concrete or mortar
binder), it can help carry the load by increasing the
tensile strength of the material.

3.1.3. Concrete curing - Do not allow any
grout to be installed until the concrete is fully
cured. Improperly cured concrete can have its
design strength reduced by as much as 50%.
Good curing practice means keeping the concrete
damp enough and at a uniform temperature long
enough so it can reach its desired compressive and
tensile strengths. The key factors in curing are 1)
shrinkage complete, 2) full tensile strength and 3)
water content reduced.

3.1.4. Concrete placement and consolidation -
Best practice is to limit the time delay between
layers of concrete to no more than 25 to 30
minutes. However, breaks in concrete placement
of as little as 15 minutes can result in a cold joint
separation between layers. Also, do not add water
to the concrete mix at the site as it will reduce the
compressive strength, the modulus of elasticity,
and tensile strength of the concrete

3.1.5. Foundation design – Best practice is to

remove all sharp corners, points, internal or “re-
entrant” corners in the foundation to reduce built-
in stress. In other words, anything that can act as
a stress riser inside the concrete must be softened
or removed. Instead, round sharp corners and
points. Install a large radius on any internal angles
in the foundation. Apply a large radius to
everything that penetrates concrete. Also, anchor
bolt holes should be round and not square and
grout pockets recessed into the concrete
foundation should be avoided. Install troughs
around the unit to take away oil.

3.1.6. Vertical connections - There should be
no vertical connections between different
materials in a foundation. For example, there
should be not be a vertical connection between
concrete and grout. Connections should be
horizontal only. Also, do not install keys or lips as
they cannot restrain thermal growth forces.

3.1.7. Edge-lifting – Edge-lifting is a common
problem on many installations. It is a de-bonding
of the concrete just below the epoxy – concrete
bond line. It can occur when large there are wide
open areas where epoxy grout covers the
foundation but does not support any equipment.
There are three methods of preventing edge-
lifting: 1) Round the outer edge of the concrete
foundation, 2) Pin the edge of the foundation
using 12 mm (½”) rebar set into a 24 mm (1”) hole
every 30 cm (12”) along the edge of the
foundation. 3) Install mechanical anchors in the
surface of the concrete. These are rebar staples or
wickets that improve the bond of the grout to the
concrete.


3.1.8. Rebar specification – Best practice is #6
(3/4”) rebar on 6” centers. Second best is #8 (1”)
rebar on 8” centers due to the increased difficulty
in placing the concrete. Dense placement in the
upper 1/3rd of the foundation block and lighter
density in the lower 2/3rds of the foundation.
Look for and eliminate stress risers that could
potentially be created in the concrete which could
be caused by the ends of rebar. Also, eliminate
possible stress points in the concrete by installing
rebar so it crosses at all internal corners of
foundation.

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Best Practices in Compressor Mounting, James A. Kuly; ITW POLYMER TECHNOLOGIES





3.2. Best Practices related to anchor
bolts, nuts and washers


The number one reason for foundation failure is
cracking, and the number one cause of cracking is
improperly designed and installed anchor bolts.
Anchor bolts cannot be eliminated so the quality
of their installation must be increased and their
negative affects must be mitigated.

3.2.1. Anchor Bolt Grade & Materials – For
reciprocating compressor mounting the anchor
bolts must be made from 4140 ASTM A193 B7
material. Nuts should be 2H.

3.2.2. Anchor Bolt Types – There are many
different anchor bolt designs. The primary
difference is the design of their termination or
bottom end. Free-standing bolts are a best practice
because they can easily be moved and positioned
without putting a strain on the bolt or concrete.
They have advantages over embedded bolts
because the holding force is governed by the bolt’s
tensile strength rather than the concrete’s tensile
strength. If bolts are to be cast into the foundation
do not cast them into the foundation until the
compressor is set in place.


3.2.3. Anchor Bolt Terminations – If free-
standing bolts are not used, then any other long
bolt can be used, but as a best practice its
terminations must be round. This not only means
that the plate at the bottom of the anchor bolt
should be round, but the plate itself must have
round edges. The diameter of the plate should be
3 to 4 times bolt diameter so that the tensile forces
on the concrete are pushed further out from the
bolt. Also, the thickness of the plate should be 1.5
x bolt diameter.

3.2.4. Free-stretch - No matter the style or type
of anchor bolt, the bolt itself must be prevented
from touching epoxy grout over the upper half of
its length. This allows the bolt to free-stretch. To
accomplish this, the upper half to the bolt must be
wrapped with tape or covered with pipe insulation
foam. Wrapping a bolt also provides the bolt with
a large thread clearance which allows the nut to
rock slightly on the bolt thread reducing the

bending stress that will be imposed on the bolt
thread.

3.2.5. Tension monitoring - It is also a best
practice to install anchor bolts with a built-in
tension monitoring device.

3.2.6. Anchor bolt length - It is best practice to
make anchor bolts as long as possible and to
terminate the anchor bolts half way into the mat.
Longer bolts reduce loss in tension resulting from
creep and reduce stress in concrete at their
termination point. In addition, long bolts separate
the stress area from the source of oil. At a
minimum the anchor bolts should be 1.2 m (48”)
in length.

3.2.7. Spherical washers – The use of
spherical washers is a best practice. Spherical
washers allow the tension on the bolt to be spread
uniformly around the anchor bolt rather than on
just one side. This is very important because nut
face angularity of 1 to 2 degrees can have a
significant effect of the fatigue life of a bolt.

3.2.8. Nuts – Anchor bolt nuts should be
ASTM A-194 high strength nuts. They must be
lubricated so the torque is not wasted in friction
between the threads or between the nut and
washer. Super nuts are a very good practice but
can be expensive.

3.2.9. Bolt torque & tension – The nuts on all
anchor bolts should be hand-tool tight while the
grout is being installed. After the grout has
hardened the bolts should be tensioned per the
equipment manufacturer’s instructions. For a tight
foundation and mounting system, the preload on
the anchor bolts should be as high as possible, but
not higher than 70% of tensile strength of bolt.

3.2.10. Bolt tensioning – The only accurate way
to tighten an anchor bolt is to stretch it. Twisting
or torquing a bolt can be very inaccurate because
torque is often wasted on friction between the
threads of the nut and bolt and between the bottom
face of the nut and the washer. Therefore the use
of a hydraulic bolt tensioner is a best practice. It
is also a best practice to re-tighten anchor bolts
after compressor and driver have come up to
temperature.

3.3. Best Practice Related To Anchor
Bolt Holes / Sleeves / Covering /
Sealing


Anchor bolt sleeves or covers are a best practice.
They cover a length of bolt so it can stretch
sufficiently when tensioned. If properly sealed top
and bottom, they also protect the bolt from
chemical attack, rust and corrosion.

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Best Practices in Compressor Mounting, James A. Kuly; ITW POLYMER TECHNOLOGIES





Many people mistakenly believe that the purpose
of a bolt sleeve is to allow the compressor installer
to easily bend the anchor bolt for alignment
purposes during compressor installation. This is
not true. Pushing an embedded anchor bolt puts a
strain on it as well as the surrounding concrete that
could lead to cracking. For this reason it is a best
practice NOT to embed any anchor bolts until the
compressor is set in place and aligned.

3.3.1. Corrugated anchor bolt sleeves are a
best practice because they
have an ability to give under
compression rather than to
drive themselves up into the
grout or down into the
concrete. In any event,
anchor bolt sleeves should be
cut off even with the top of
the concrete. If they are
allowed to stick partway up
into the grout, they will
eventually crack the grout.

3.3.2. Not too close to the edge - It is good
practice to keep bolts and pockets as far as
possible away from the sides of the foundation –
30 cm (12” minimum)

3.3.3. Well sealed – the top and bottom of the
sleeves should be well sealed to prevent them
from filling up with oil or water.

3.3.4. Wrap bolt threads - The bolt threads
sticking up above sleeve must be covered using
foam backed tape or foam pipe insulation. This
prevents grout or chocking compound from going
up into the bolt hole on the compressor and
preventing the bolt from moving or stretching.

3.4. Best Practices Related To
Expansion Joints

The use of expansion joints is a best practice.
Expansion joints serve 2 purposes – 1) they
prevent the concrete and epoxy grout from coming
apart due to the difference in thermal expansion
and contraction rates
and 2) they guide
flow of grout into
areas of limited size.
Using expansion
joints will ensure that
the epoxy grout
flows everywhere it
is needed and that it
will stay in place
once there.


3.4.1. Proper
layout - Proper
spacing and

configuration of expansion joints is usually based
on the grout used and the extremes of weather and
the thermal cycling expected. The larger the
expected difference in seasonal temperatures the
closer the expansion joints should be but is
typically either 1.2 m (4 ft) square or 1.8 m (6 ft)
square.

3.4.2. Well sealed - Expansion joints must be
well sealed at the bottom so they cannot allow any
liquids to pass down next to them.

3.5. Best Practices Related To
Alignment Tools


Some sort of jacking device must be used to
position the compressor and driver. There are
many different types of jacking devices and all
(except nuts on anchor bolts under the mounting
plate) are acceptable IF they are removed
completely from the grout. Jacks, wedges, shims,
and blocks of any shape or size must never be left
inside the grout. Cracks are guaranteed if they are.

3.5.1. Jacking screws - The best practice here
is to use jacking screws (d) and back out the screw
completely after the grout has cured. This can be
done if the threads of the jacking screws are
coated with non-melt grease. Jacking devices that
are isolated and grouted around must have a
second pour to fill in the space where the jacking
screw was located. This is costly and
unnecessary. The best practice is to use jacking
screws with non-melt grease on their threads. This
is more cost effective as it allows the entire area to
be grouted at one time.




3.5.2. Round landing plate - Another best
practice is to have the jacking screw touch down
on a relatively thin, round, landing plate with
rounded edges. This provides a stable place for
the jacking screws to rest that will not add any
stress risers to the grout.

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Best Practices in Compressor Mounting, James A. Kuly; ITW POLYMER TECHNOLOGIES





Bond the round landing plates to the surface of the
concrete with a fast setting epoxy paste.

3.6. Best Practices Related To Epoxy
Grout & Chocks

Only epoxy grout and epoxy chocking compound
are discussed in this section as their use is
considered a “Best Practice” over cementitious
grouts. It is important to first differentiate
between an epoxy “Grout” and an epoxy “Chock”
or “Chocking Compound.” Epoxy grouts are
mixtures of resin, hardener, and aggregate.
Because of the aggregate, grouts have the
consistency of lumpy oatmeal. However, the
aggregate also allows the grout to be poured in
large, thick sections because it absorbs the
exothermic heat created by the resin and hardener.
Epoxy chocking compounds have no aggregate.
As a result they get much hotter and must be
poured in small blocks typically around individual
anchor bolts. Chocking compounds have a
smooth and creamy consistency.

3.6.1. Eliminate stress risers in grout and
chocks. Stress risers are created when re-entrant
angles are cast into the grout, equipment mounting
feet or sole plates with sharp corners instead or
well rounded corners are installed in the grout.
Also, screw threads, welding slag, sharp edges,
and points of any kind increase the stress in both
grout and chocks which can lead to cracking.

3.6.2. Manage temperatures of the grout and
chock to eliminate over heating. Over heating can
cause high thermal stresses that can lead to
cracking. High temperatures also cause an over
expansion of the epoxy followed by an over
contraction that can lead to soft foot problems.

3.6.3. Manage depth of pour – The larger the
mass of epoxy chock or grout, the more
exothermic heat it generates and that too can lead
to a larger than expected expansion then
contraction in the epoxy. For this reason the depth
of pour is important. For most epoxy grouts the
maximum depth should be no more than 30 cm
(12”). The depth of most epoxy chocking
compounds should be about 5 cm (2”).

3.6.4. Grout / Chock level - Most installation
drawings show the level of grout or chock at the
same level as the bottom of the mount. This is not
correct and should not be done. The grout/chock
level should always be 12mm to 24 mm (1/2 to 1”)
above the bottom of the mount. This puts a head
pressure on the epoxy surrounding the mount
which in turn puts an upward force on the epoxy
under the mount. This upward force ensures that
any contraction in the epoxy has little or no effect
on the alignment.

3.6.5. Chock Overpour – The overpour is not
just the place where the chocking compound is
poured in place. The overpour also plays a vital
role in the curing of the chocking compound. It is
the place where the chocking compound can
expand up into and contract down from so the
epoxy in it must remain cool and liquid. This is
done using metal dams placed no more than 19
mm (3/4 inch) away from the mounting foot. The
overpour should be along the long side of the
mounting foot. It can also be on the opposite long
side but it should never extend around the entire
mounting foot.

3.6.6. Foam strip - Install a foam strip around
the mounting foot or sole plate to take up a small
amount of shaking movement without causing the
chock or grout to crack.

3.7. Best Practices Related To Coating
and Sealing the Foundation

After the compressor and driver have been grouted
and/or chocked in place and the forms removed,
prepare the exposed concrete surfaces under and
around the installation by following these best
practices.

3.7.1. Concrete preparation - The surface of
the foundation must be firm, free of any laitance
or efflorescence, clean, free of any adverse
moisture conditions, have an appropriate surface
profile, and be fully cured before coating. Newly
poured concrete must age at least 30 days at
temperatures over 70°F before coating. Form
release agents, sealers, curing compounds, salts,
hardeners and other foreign matter will interfere
with adhesion and must be removed. Shot-
blasting, mechanical scarification, suitable
chemical means, or sandblasting should be
employed to prepare substrate. The surface profile
of the concrete should be CSP-3 to CSP-5 meeting
ICRI (International Concrete Repair Institute)
standard guideline #03732 for coating concrete,
producing a profile equal to 60-grit sandpaper or
coarser. Moisture vapor transmission should be
1.4 kg (3 pounds) or less per 93 square meter
(1,000 square feet) over a 24 hour time period, as
confirmed through a calcium chloride test, as per
ASTM E-1907. All surface irregularities, cracks,
expansion joints and control joints should be
properly addressed prior to application.

3.7.2. Concrete coating – Mix and apply an
epoxy primer and a 2-part, 100% solids, epoxy top
coat over the concrete areas not covered by epoxy
chocks or grout. This will protect the surrounding
areas from oil penetration.

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