Integral Waterproofing System with a focus on Penetron

Advantages of the Penetron® Integral
Waterproofing System with a focus on
Penetron® Admix
Contents
1.
Introduction .................................................................................................................... 4
2.
Problems associated with concrete waterproofing .......................................................... 4
3.
2.1.
Corrosion ................................................................................................................ 5
2.2.
Carbonation ............................................................................................................ 6
2.3.
Cracking ................................................................................................................. 6
2.3.1.
Plastic shrinkage cracking................................................................................ 6
2.3.2.
Drying shrinkage .............................................................................................. 7
2.3.3.
Thermal cracks ................................................................................................ 7
2.3.4.
D-Cracking ....................................................................................................... 7
2.4.
Alkali Silica Reaction (ASR) .................................................................................... 8
2.5.
Damage due to freeze-thaw cycles ......................................................................... 9
2.6.
Concrete deterioration due to chemical attack ...................................................... 10
2.7.
Sulfate attack ........................................................................................................ 11
2.8.
Concrete structures in marine environments ......................................................... 11
Waterproofing with Penetron Admix ............................................................................. 12
3.1.
How it works ......................................................................................................... 12
3.2.
Features and benefits of Penetron Admix ............................................................. 13
3.2.1.
Permanent concrete protection ...................................................................... 13
3.2.2.
Self-healing concrete ..................................................................................... 14
3.2.3.
Corrosion protection of reinforcement steel with Penetron Admix .................. 16
3.2.4.
Protection against chloride penetration .......................................................... 17
3.2.5.
Protection against carbonation ....................................................................... 19
3.2.6.
Crack bridging ability of Penetron .................................................................. 19
3.2.7.
Increase in compressive strength................................................................... 22
3.2.8.
Resistance against high water pressure......................................................... 22
3.2.9.
Chemical resistance....................................................................................... 25
3.2.10. Resistance to freeze-thaw cycles ................................................................... 28
3.2.11. Compatibility with commonly-used concrete mix designs (Penetron Admix) .. 28
3.2.12. Prevention of Alkali-Silica-Reaction (ASR) ..................................................... 29
3.2.13. Limitations ..................................................................................................... 29
3.2.13.1.
Cold joints .................................................................................................. 29
3.2.13.2.
Active leaks ................................................................................................ 30
3.2.13.3.
Concrete defects ........................................................................................ 30
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3.2.13.4.
Structural cracks ........................................................................................ 30
3.2.13.5.
Exposed concrete structures (thermal cracks) ............................................ 30
4.
At one glance - Benefit overview .................................................................................. 31
5.
Comparison of Penetron products with other waterproofing systems ........................... 32
5.1.
6.
Comparison between Penetron and hydrophobic pore blockers............................ 34
Application instructions – Penetron Admix ................................................................... 35
6.1.
Description ............................................................................................................ 35
6.2.
Dosage Rate ......................................................................................................... 36
6.3.
Mixing ................................................................................................................... 36
6.3.1.
Ready Mix Plant – Dry Batch Operation ......................................................... 36
6.3.2.
Ready Mix Plant - Central Mix Operation ....................................................... 36
6.3.3.
Precast Batch Plant ....................................................................................... 36
6.3.4.
Technical Services ......................................................................................... 36
6.4.
Setting time and strength ...................................................................................... 37
6.5.
7.
Application instructions – Penetron .............................................................................. 37
7.1.
Description ............................................................................................................ 37
7.2.
Consumption......................................................................................................... 37
7.2.1.
Construction slabs ......................................................................................... 37
7.2.2.
Construction joints ......................................................................................... 38
7.2.3.
Blinding concrete ........................................................................................... 38
7.3.
Surface Preparation .............................................................................................. 38
7.4.
Mixing ................................................................................................................... 38
7.5.
Application ............................................................................................................ 38
7.5.1.
Slurry consistency .......................................................................................... 38
7.5.2.
Dry powder consistency (for horizontal surface only) ..................................... 38
7.6.
8.
9.
Limitations ......................................................................................................... 37
Post treatment ................................................................................................... 38
Application instructions – Penetron Plus ...................................................................... 39
8.1.
Description ............................................................................................................ 39
8.2.
Coverage .............................................................................................................. 39
8.3.
Application Procedures ......................................................................................... 39
8.4.
Curing ................................................................................................................... 40
8.5.
Technical Services ................................................................................................ 40
Contact and Disclaimer ................................................................................................ 40
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Table of Figures
Figure 1 Corrosion stages ..................................................................................................... 5
Figure 2 Example of plastic shrinkage cracks ....................................................................... 8
Figure 3 Example of drying shrinkage cracks ........................................................................ 8
Figure 4 Example of thermal cracking ................................................................................... 8
Figure 5 Example of D-cracking ............................................................................................ 8
Figure 6 Scanning electron microscope image of chert aggregate particle with numerous
internal cracks due to ASR; cracks extend into the adjacent cement paste ........................... 9
Figure 7 Detail of aggregate showing alkali-silica gel extruded into cracks within the concrete.
Ettringite is also present within some cracks ......................................................................... 9
Figure 8 Examples of ASR damage ...................................................................................... 9
Figure 9 Example of freeze-thaw damage on roads and bridge decks ................................ 10
Figure 10 Example of concrete damage caused by chemical attack ................................... 11
Figure 11 How Penetron works ........................................................................................... 13
Figure 12 Scanning Electron Microscope Photograph of Penetron crystals......................... 13
Figure 13 Test setup, MFPA Leipzig, Germany, 2006 ......................................................... 14
Figure 14 Water flow through 0.2mm crack at water pressures of 0.1, 0.5 and 1.0 bar ....... 15
Figure 15 Water flow through 0.25mm crack at water pressures of 0.1, 0.5 and 1.0 bar ..... 15
Figure 16 Excerpt: Permeability of Penetron-Admix-treated concrete vs. control sample
(ENCO, 2006) ..................................................................................................................... 17
Figure 17 Excerpt: Chloride permeability of Penetron Admix (AASHTO-T-277: Shimel and
Sor, USA, 2005) .................................................................................................................. 18
Figure 18 Excerpt: Results of the rapid chloride penetration test at Sardar Patel, India, 2009
........................................................................................................................................... 18
Figure 19 Seawall treated with Penetron Admix, Portocel, Aracruz, Brazil .......................... 19
Figure 20 The Capri, Miami Bay, USA. Basement structure treated with Penetron Admix ... 19
Figure 21 Backscattered Electron Image (BEI) of Penetron crystals forming in a crack. ...... 20
Figure 22 Needle-like, elongated Penetron forming in the cracks ........................................ 20
Figure 23 Excerpt: Permeability results of cracked concrete samples treated with Penetron
........................................................................................................................................... 21
Figure 34 OFI sample set-up (Penetron ―sandwich-system‖)............................................... 21
Figure 24 Excerpt: Test results for Penetron Admix under 20 bar head water pressure,
University of Bologna, Italy, 2005 ........................................................................................ 25
Figure 25 University of Bologna: Chemical resistance test - Test set up ............................. 26
Figure 26 University of Bologna: Chemical resistance test - results .................................... 27
Figure 27 Milan South Waste Water Treatment Plant, Italy ................................................. 28
Figure 28 SABESP Sewage Treatment Plant, Brazil ........................................................... 28
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1. Introduction
Penetron integral concrete capillary waterproofing systems are being used for more than
three decades to effectively waterproof and protect concrete structures around the world.
This document explains the most common problems associated with concrete structure in
contact with water and under different environmental conditions.
The text further elaborates on how to address and prevent these problems with the help of
Penetron® integral concrete capillary waterproofing systems in order to enhance the
durability of concrete and effectively protect structures.
2. Problems associated with concrete waterproofing
Concrete is the most commonly-used man made construction material in the world. It
possesses a relatively good resistance to water and structural concrete elements can be
shaped rather easily into various shapes and sizes. Despite its durability, concrete – even
high-quality concretes – is a porous material. Evaporating excess water in the hydration
stage of the concrete will leave millions of pores and capillaries in concrete. Further the
interfacial transmission zones (IZT) – a part of the concrete microstructure that describes the
zone, which exists between the hydrated cement paste and large particles of aggregate –
are prone to cracking during the hardening stage of the concrete due to shrinkage,
temperature stresses and externally applied loads. These microcracks in the interfacial
transition zone are usually larger than most capillary cavities present in the concrete. The
pores and microcracks (especially if interconnected throughout the concrete) increase the
porosity of the concrete matrix and will allow air and water to enter the hardened concrete.
This will result in corrosion of the embedded reinforcement steel and in other concrete
damages caused by water-borne salts and chemicals and further contribute to the
deterioration and weakening the strength of the concrete, directly affecting its durability.
Water (seawater, groundwater, river water, lake water, snow, ice and vapor) is a primary
agent for both creation and destruction of concrete – and is deeply involved in nearly every
form of concrete deterioration. Field experience shows that, in order of decreasing
importance, the principal causes for deterioration are the corrosion of reinforced steel,
exposure to cycles of freezing and thawing, alkali-silica reaction, and chemical attack.
With each of these four causes of concrete deterioration, the permeability and presence of
water are implicated in the mechanisms of expansion and cracking.
The problem of porosity and cracking of concrete is increased in structures that are
constantly exposed to different loads, stress redistribution and tectonic seismic influences.
The following chapter focuses on the major deterioration causes of concrete:
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2.1. Corrosion
The corrosion of the steel reinforcement is the most common source of distress in concrete,
especially concrete that is located near or under water. Corrosion of steel is an
electrochemical process and basically is the transformation of metallic iron to rust, which is
accompanied by an increase in volume (which in some cases – depending on the state of
oxidation - can be as much as 600 percent of the original steel). This expansion of the rebar
is then leading to concrete expansion and cracking, followed by spalling and eventually to a
complete loss of the concrete cover. The final result will be the weakening of the structures’
strength and ultimately its failure.
Corrosion can occur when two dissimilar metals are embedded into concrete (such as e.g.
steel and aluminum), because each metal has a unique electrochemical potential. The
concrete then effectively becomes a battery. When the metals are in contact in an electrolyte,
the less active metal corrodes.
If only one type of steel is present in the concrete, corrosion is generated by differences in
the concentration of dissolved ions, such as alkalies and chlorides. These ions are
introduced to the concrete by water penetrating into the pores and microcracks.
Figure 1 Corrosion stages
Hydrated Portland cement contains alkalies in the pore fluid and a sufficient amount of solid
calcium hydroxide in order to maintain an alkalinity level with a pH value above 12. In an
alkaline environment (pH value above 11.5) normal steel and iron form a thin, impermeable
and strongly adherent iron-oxide film that makes the metals passive to corrosion. However,
once the alkalies and most of the calcium hydroxide have either carbonated or leached away,
the pH of the concrete surrounding the reinforcement may drop below 11.5 destroying the
passivity of steel and allowing the corrosion process to start. In the presence of chloride ions
the passivating film is destroyed even at pH values of above 11.5. The main causes of
chloride in concrete are admixtures, salt-contaminated aggregate and penetration of deicing
salt solutions and seawater.
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2.2. Carbonation
Carbonation occurs when carbon dioxide from the air penetrates the concrete and reacts
with hydroxides, such as calcium hydroxide, to form carbonates. In the reaction with calcium
hydroxide, calcium carbonate is formed.
This reaction reduces the pH of the pore solution to as low as 8.5, at which level the passive
iron-oxide film of the steel is not stable and corrosion will set in.
Carbonation is highly dependent on the relative humidity of the concrete. The highest rates
of carbonation occur when the relative humidity is maintained between 50% and 75%. Below
25% relative humidity, the degree of carbonation that takes place is considered insignificant.
Above 75% relative humidity, moisture in the pores restricts CO2 penetration. Carbonationinduced corrosion often occurs on areas of building facades that are exposed to rainfall,
shaded from sunlight, and have low concrete cover over the reinforcing steel.
Carbonation of concrete also lowers the amount of chloride ions needed to promote
corrosion. In new concrete with a pH of 12 to 13, about 7,000 to 8,000 ppm of chlorides are
required to start corrosion of embedded steel. If, however, the pH is lowered to a range of 10
to 11, the chloride threshold for corrosion is significantly lower—at or below 100 ppm. Like
chloride ions, however, carbonation destroys the passive film of the reinforcement, but does
not influence the rate of corrosion.
2.3. Cracking
Cracks generally increase the porosity of concrete and allow water and water-borne salts
and chemicals to enter the concrete and accelerate its deterioration. Cracking of concrete
can have a number of causes. In this document we only want to focus on the most common
types of cracks in concrete structures.
2.3.1. Plastic shrinkage cracking
Plastic shrinkage cracks occur due to a rapid loss of water from the surface of concrete
before it has set. This happens when the rate of evaporation of surface moisture of freshly
placed concrete exceeds the rate at which bleed water can replace it. Tensile stresses
develop in the weak, hardening plastic concrete as a result of the restraint provided by the
concrete below the drying surface layer. Plastic shrinkage cracks are usually shallow in
nature and do not intersect the perimeter of the slab. However, like every crack they provide
a possible entry-point for water and chemicals into the concrete structure and as such a
starting point of the deterioration process.
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2.3.2. Drying shrinkage
As almost every concrete mix design contains more water than is needed to hydrate the
cement, much of the remaining water evaporates, causing the concrete to shrink. Restraint
to shrinkage, provided by the subgrade, reinforcement or another part of the structure,
causes tensile stresses to develop in the hardened concrete. Restraint to drying shrinkage is
the most common cause of concrete cracking.
2.3.3. Thermal cracks
Thermal cracking takes place if an excessive temperature difference exists within a concrete
structure or its surroundings. This difference in temperature causes a higher contraction of
the cooler portion over the warmer part of the concrete. This restrains the contraction. If the
restraint causes tensile stresses that exceed the placed concrete’s tensile strength, thermal
cracks will occur. In some climate zones thermal cracks can occur as a result of the
atmospheric temperature differences. During daytime high temperatures cause the concrete
to heat up and expand. At night the air temperature falls significantly and leading to a
contraction of the concrete mass. This can cause concrete to crack. Due to the expansion
and contraction of the concrete in air temperature differences these cracks widen further
over time.
2.3.4. D-Cracking
D-cracking is a form of freeze-thaw-cycle deterioration and often observed in concrete
pavements (usually taking place along the joints). Water accumulation in the base of the
concrete ultimately saturates the aggregate. Once free-thaw cycles set in the aggregate
begins to crack and subsequently crack open the concrete. This process usually starts at the
bottom of the slab and progresses upwards to the surface.
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Figure 2 Example of plastic shrinkage cracks
Figure 3 Example of drying shrinkage cracks
Figure 4 Example of thermal cracking
Figure 5 Example of D-cracking
2.4. Alkali Silica Reaction (ASR)
Alkali-silica reaction (ASR) is the most common form of alkali-aggregate reaction (AAR) –
together with the much less common form alkali-carbonate-reaction ACR – and can cause
serious expansion and cracking in concrete, resulting in major structural problems and
sometimes necessary demolition. ASR is caused by a reaction of between the hydroxyl ions
in the alkaline cement pore solution in the concrete and reactive forms of silica in the
aggregate (e.g. chert, quartzite, opal, strained quartz crystals). A gel is produced, that
increases in volume by taking up water and so exerts an expansive pressure, resulting in the
failure of concrete. This gel can occur in cracks and even within the aggregate particles.
In order for ASR to occur in concrete a sufficiently high alkali content of the cement (or alkali
from other sources), a reactive aggregate (e.g. chert or quartzite) and finally water is needed
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for the reaction. If no water is present in the concrete, no ASR will take place as the alkalisilica gel formation requires water.
The best way to avoid ASR is to use non-reactive aggregates, which are not always
available. In this case it is essential for the concrete mix designer to be aware of the Na2Oequivalent (in %) of all products used in the concrete mix. This is to ensure that the Na2O
equivalent value does not exceed the acceptable amount per m3 (usually set around
3.5kg/m3).
Figure 6 Scanning electron microscope image of chert
aggregate particle with numerous internal cracks due to
ASR; cracks extend into the adjacent cement paste
Figure 7 Detail of aggregate showing alkali-silica gel
extruded into cracks within the concrete. Ettringite is also
present within some cracks
Figure 8 Examples of ASR damage
2.5. Damage due to freeze-thaw cycles
In cold climates damage to concrete pavements, retaining walls, bridge decks and railings
attributable to freeze-thaw cycles is one of the major causes for repair and maintenance
works. Water molecules are very small and therefore able to penetrate even the finest
concrete pores and capillaries. Once water has entered the capillary system and freezes it
will expand in volume and dilate the concrete pore or cavity by exerting hydraulic pressure
generated by the expansion. This pressure will slowly – over the span of multiple cycles –
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widen the pores or capillaries. Once the water in the pores thaws it will advance deeper into
the concrete where the process is repeated once the water in freezes again and so forth.
Damages caused by freeze-thaw cycles are most commonly cracking and spalling of
concrete due to progressive expansion of the cement paste. The freeze-thaw effect is
drastically enhanced if moisture and deicing salts – used in road maintenance – are present,
which can lead to maximum scaling of the concrete surface. Spalling and cracking of the
concrete will ultimately expose the embedded reinforcement steel to corrosion due to
chloride and water penetration.
Figure 9 Example of freeze-thaw damage on roads and bridge decks
2.6. Concrete deterioration due to chemical attack
A well-hydrated cement paste provides a very alkaline environment in concrete with pH
values ranging from 12.5 to 13.5. As a result of the contact between acidic environmental
conditions and the concrete this alkaline environment is disturbed and lead to a lowering of
the pH level. Depending on the acidity of the attacking chemical concrete deteriorates slower
or faster. The effects of concretes under chemical attack always result in an increase of the
porosity and permeability, cracking and spalling and subsequently in a loss of strength. The
combination of the physical deterioration and persisting exposure to the chemical attack
continue and accelerate the deterioration of the concrete over time.
Chemical attacks involve attacks by acidic solutions promoting the formation of soluble
calcium salts, insoluble and non-expansive calcium salts and solutions containing
magnesium salts. In the following context this document will focus on other chemical attacks
that involve the formation of expansive products (due to internal stress), such as sulfate
attacks, delayed ettringite formation, alkali-aggregate reaction (AAR) and corrosion.
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Figure 10 Example of concrete damage caused by chemical attack
2.7. Sulfate attack
Sulfate attacks can result either in an expansion and cracking of concrete or lead to a
gradual decrease in the compressive strength.
Cracking and spalling allows aggressive and corrosive (ground) water to penetrate more
easily as a direct result of increased permeability, which will effectively accelerate the
deterioration of the affected concrete. This is also known as external sulfate attack.
A weakening of the concrete is achieved through the detachment of the cement paste from
the aggregates, such as caused by delayed ettringite formation (DEF), which is usually
considered as internal sulfate attack as it involves sulfate ions contained in the concrete (e.g.
cement containing an unusually high sulfate content). DEF causes cracks in the cement
paste and the aggregate-cement paste interface resulting from an expansion due to the
formation of ettringite around the aggregates. DEF occurs in the late ages of the concrete
when sulfate ions released by the decomposition of ettringite are absorbed by calciumsilicate hydrate. Once the sulfate ions are desorbed, the re-formation of ettringite causes
expansion that leads to cracking.
2.8. Concrete structures in marine environments
In a marine environment concrete is exposed to a combination of deterioration effects.
These include primarily the chemical reaction of seawater with the concrete, penetration of
salts and chlorides during wetting/drying conditions, freeze-thaw-cycles in cold climates,
corrosion of the reinforcement steel and physical erosion due to wave action. Due to
intermingling of these effects concrete structures in marine environments bear higher risks of
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deterioration and special considerations should be taken into account in order to ensure the
durability of these structures.
3. Waterproofing with Penetron Admix
Penetron Admix, a 3rd generation crystalline, concrete-enhancing admixture, is the most
advanced formula to effectively waterproof concrete structures. It eliminates problems
related with 1st and 2nd generation admixtures such as loss of compressive strength and
unusually long delays of the setting time.
Penetron Admix can be applied to any commonly-used concrete mix in today’s’ construction
industry. It doesn’t have any known incompatibilities with other workability enhancing
admixtures such as retarders or superplastizicers and there are no limitations in regards to
the w/c ratio of the concrete to be treated. With dosages rates as low as 0.8% (by weight of
cement) it is not only one of the most cost-efficient and economic waterproofing choices, but
an effective formula that has been proven in many international laboratory tests and on
countless projects worldwide.
Penetron Admix is a non-toxic product and is approved for use in projects involving potable
water (NSF 61 approval, European Environmental License). Penetron Admix does not
contain any volatile organic compounds (VOC) and is used in green projects acquiring LEED
certification points.
When applied to concrete Penetron Admix assists in the hydration process acting as a
catalyst to un-hydrated cement particles already existing in the concrete. This already takes
place in the early stages of the cement-reaction resulting in the development of internal
strength build up compensating to some extent the formation of shrinkage cracks as well as
the increase in compressive strength. At the same time a longer workability of the fresh
concrete is provided.
3.1. How it works
Penetron Admix is added to the concrete mix at the time of batching at dosage rates
between 0.8-1% by weight of cement (alternatively Penetron Admix can be added into the
mixing truck on site before the concrete is poured). The activating chemicals of Penetron
Admix react with water, calcium hydroxide and aluminum as well as other metal oxides
contained in the concrete to form a web of insoluble crystals. These crystals seal all existing
capillaries, micro-cracks and voids of up to 0.4mm for the lifetime of the concrete. Once
formed, the crystal formations will prevent water, water-borne salts and a wide range of
chemicals from entering and moving through the concrete and protect it permanently. Air is
still allowed to pass through the crystalline formations allowing the concrete to breathe and
avoiding build-up of vapor pressure.
Page | 12
Penetron Admix will subsequently enhance concrete properties resulting in an increased
compressive strength and reduced shrinkage cracks.
In addition Penetron Admix will provide a ―self-healing‖ concrete. In absence of moisture the
activating chemicals remain dormant in the concrete for years. If cracks occur at any time
the Penetron Admix components are activated by any penetrating moisture. As a result the
chemical reaction will resume automatically and the developing crystals will practically ―selfheal‖ the new crack, sealing it off completely.
Figure 11 How Penetron works
3.2. Features and benefits of Penetron Admix
3.2.1. Permanent concrete protection
Penetron Admix is a permanent application. It becomes an
integral part of the concrete by forming insoluble crystals in the
capillaries, pores and microcracks in concrete of up to 0.4mm.
Once these crystal formations have developed in the concrete
matrix they will stay there for the lifetime of the concrete turning
the concrete itself into the water barrier. Unlike barrier products
(membranes, cementitious coatings) Penetron-treated concrete
will remain its waterproofing and protection properties even if
the surface is damaged. Penetron Admix does not require reapplication.
Figure 12 Scanning Electron
Microscope Photograph of
Penetron crystals
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3.2.2. Self-healing concrete
Penetron Admix is an active waterproofing admixture that provides projects with a selfhealing concrete. Being a hydrophilic product Penetron Admix reacts with moisture to form
crystals in cracks and voids of the concrete. Should new water enter through newly formed
cracks in the structure – even years after construction – the chemical reaction of Penetron
Admix will resume. Penetron crystal formations will develop and ultimately seal these new
cracks as well.
A test performed at the MFPA in Leipzig, Germany1 examined the self-healing behavior of
Penetron Admix-treated concrete. In order to simulate the self-healing effects crackcontaining concrete cubes were produced by placing new, Admix-treated concrete
(containing 1% Penetron Admix by weight of cement) onto already cured concrete
(containing 1% Penetron Admix). After curing the two halves were forced apart by wedges to
create a joint of 0.2mm, 0.25mm. A 0.1 bar (1m water-column) water pressure was applied
at each of the joints and the flow-through of water through at both joints was measured (see
figure 13). It was observed that the water-flow through the joints continuously decreased
over time. Once the water-flow reached a value of less than 5 cubic centimeters per hour,
the pressure was raised to 0.5 bar (5m water-column) and the water-flow through the joint
was measured. After the flow was reduced to less than 5 cubic centimeters per hour the
pressure was raised to 1.0 bar (10m water-column). In both cases a sealing of the joints was
observed.
Figure 13 Test setup, MFPA Leipzig, Germany, 2006
1
MFPA Leipzig GmbH, Germany – Department of Structural Engineering: “Application-technology tests on
concrete test specimens with and without adding the sealing agent Penetron Admix (May 31, 2007)”
Page | 14
Following tables show the water flow through the joints at different water pressures (0.1 bar,
0.5 bar, 1.0 bar).
Figure 14 Water flow through 0.2mm crack at water pressures of 0.1, 0.5 and 1.0 bar
Figure 15 Water flow through 0.25mm crack at water pressures of 0.1, 0.5 and 1.0 bar
The self-healing properties of Penetron Admix-treated concrete prevent penetration of water,
chemicals and other corrosive agents from entering the concrete through cracks that form in
the later stage in the lifetime of the structure.
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3.2.3. Corrosion protection of reinforcement steel with Penetron Admix
By sealing the capillaries, pores and microcracks of concrete with insoluble crystal
formations Penetron Admix reduces the permeability of the concrete and denies water and
corrosive chemicals the entryway into the concrete structure. Water-borne salts, chlorides
and other chemicals are prevented from reaching the reinforcement steel and start corrosion
by breaking down (lowering of the pH levels) the alkaline surrounding of the concrete and
the protective coating of the rebar.
A test performed at the renowned ENCO Laboratory2 clearly shows a reduction of water
penetration (reduction of permeability) into Penetron Admix-treated concrete compared to
the control concrete.
In the second series of this test concrete samples containing 1% Penetron Admix (by weight
of cement) were water cured for 10 days. The samples were then subjected to a water
pressure of 9 atm (9 bar) (10 days for the samples with a w/c ratio of 0.65 and 20 days for
the samples with a w/c ratio of 0.43). The samples were then again placed in water for an
additional 10-20 days until the start of the actual water permeability tests with a pressure of 5
atm (5 bar).
The Penetron Admix-treated samples (w/c=0.65) show a significant improvement in the
water penetration compared to the control sample. The table below shows the detailed
results.
2
Evaluation of the efficacy of the additives Penetron Admix and Penetron in porous and cracked concretes
(second test series); ENCO Laboratory, Italy, 2006
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Figure 16 Excerpt: Permeability of Penetron-Admix-treated concrete vs. control sample (ENCO, 2006)
Apart from isolating the reinforcement steel from the external environment, cured Penetron
(Penetron is Portland cement –based) has an alkalinity of around pH 11 and will thus
prevent the steel from corroding by adding more alkalinity to the mix. Moreover, by
preventing soluble alkaline salts (calcium hydroxide) from being flushed out of the concrete
due to water migration and by densifying the concrete matrix to reduce carbon dioxide gas
diffusion, Penetron will help to maintain the alkaline environment that is necessary to protect
the reinforcing steel.
3.2.4. Protection against chloride penetration
Chlorides are the major factor in precipitating corrosion in concrete and enter the concrete
mass usually by migration into the capillary system over time.
Independent testing has established that the chloride content of Penetron Admix itself is very
low (<0.10% aggregate3) and its waterproofing effects are not related to chlorides. Penetrontreated concrete was found to be resistant to acidic and alkaline conditions ranging from pH
3 to 114.
3
Electrochemical analysis of a concrete additive “PENETRON ADMIX” according to DIN V 18998 [1], MFPA
Stuttgart, Germany, 2008
4
Testing of Penetron Waterproofing Materials for Chemical Resistance; Shimel and Sor Testing Laboratories Inc.,
Report No. 93-3981, 1993
Page | 17
International tests have shown that Penetron Admix-treated concretes significantly reduce
the penetration of chloride ions into the concrete. In a test according to AASHTO-T-277
undertaking in 20055, Penetron Admix-treated concrete reduced the chloride permeability by
more than 80% compared to the control sample.
Figure 17 Excerpt: Chloride permeability of Penetron Admix (AASHTO-T-277: Shimel and Sor, USA, 2005)
In another test6 Penetron Admix-treated concrete was tested for Rapid Chloride Penetration
(RCPT) according to ASTM C1202. The results below show a clear reduction of chloride
penetration of over 45% between the control sample and the Penetron Admix sample.
Figure 18 Excerpt: Results of the rapid chloride penetration test at Sardar Patel, India, 2009
As proven in the above test reports Penetron significantly reduces chloride ion penetration
as it prevents the ingress of salt solutions, which allow chloride ions to migrate through the
concrete structure (diffusion).
Structures exposed to cyclic wetting and drying, such as marine structures (bridges, piers,
sea walls, etc.) where salt laden media are in direct (or indirect) contact with the concrete,
are especially susceptible to chloride ion ingress. Penetron Admix help to protect these
structures effectively against chloride penetration and water ingress.
5
Laboratory Tests of Penetron Admix in Concrete, Sor Testing Laboratories, Inc., USA Report No. 05-4070A,
2005
6
Performance evaluation of waterproofing products based on crystallization; Sardar Patel College of Engineering,
Mumbai, India, 2009
Page | 18
Figure 19 Seawall treated with Penetron Admix,
Portocel, Aracruz, Brazil
Figure 20 The Capri, Miami Bay, USA. Basement
structure treated with Penetron Admix
3.2.5. Protection against carbonation
Another factor for corrosion is carbonation.
In practice, the atmospheric environment slowly permeates the concrete surface. This
carbonation process progressively reduces the pH of the pore solution in the affected area.
Where carbonation progresses far enough into the concrete surface to reach the reinforcing
bar, corrosion of the re-bar will be initiated.
The rate at which carbonation progresses in concrete depends on a number of factors
including the humidity of the concrete, exposure conditions, concrete quality and strength,
compaction and curing as well as the water/cement ratio of the concrete mix.
The water/cement ratio is particularly important. Increasing the water/cement ratio from 0.45
to 0.60 will double the rate of carbonation because of increased porosity. In good quality
concrete, the carbonation rate may be negligible while low quality concretes may show 1mm
per year.
Penetron drastically reduces carbonation by reducing the porosity of the concrete and
narrowing the capillary tracts. By producing a stronger, denser concrete the diffusion of
carbon dioxide gas will be inhibited and as the crystalline growth blocks and fills the capillary
tracts the amount of gas able to penetrate the concrete will be reduced. Recent studies have
established that even though the crystal growth structures are breathable, the diffusion of
carbon dioxide gas was reduced by 42% when compared to a reference concrete.
3.2.6. Crack bridging ability of Penetron
Cracking is an inevitable result of the curing process and increases the permeability of the
concrete. The larger the cracks the more susceptible the concrete becomes towards ingress
of water and corrosive agents.
Penetron will seal shrinkage cracks, pores and capillaries of up to 0.4mm blocking the
passage-way into the concrete and protecting it from corrosion and resulting deterioration.
Due to the self-healing ability of Penetron products, new cracks are repaired automatically
as soon as moisture enters.
Page | 19
Figure 21 Backscattered Electron Image (BEI) of
7
Penetron crystals forming in a crack .
Figure 22 Needle-like, elongated Penetron forming
in the cracks
In order to demonstrate the crack sealing ability of Penetron tests were undertaken at the
ENCO Laboratory8 in Italy.
The tests were performed on 10x10x10cm test cubes with a w/c ratio of ≤0.55 thus
prepared:
-
curing for 5 days at 20°C and RH >95%;
cracking by means of the Brazilian indirect tensile strength test and inclusion in a
15x15x15 cm test cube with high performance premixed ―betoncino‖ concrete
cement;
curing for 5 days at 20°C and RH >95%;
grinding and sealing with water/Penetron slurry = 0.45 applied along the crack and
then in quantities of 1kg/m2 along the entire surface exposed to water penetration;
curing at 20°C and RH >95% for 2 days, then in water at 20°C for 60 days.
At the end of the 60 days both the cracked test pieces sealed with Penetron and the
reference pieces prepared using the same concrete not cracked, underwent a water
impermeability test according to the UNI EN 12390-8 standard (3 days at 5atm.).
The results of these tests are shown in the table below.
7
Microscopic analysis of the concrete cores from retaining wall at Changi Airport Terminal 3; SETSCO Services
Pte Ltd., Singapore, 2002
8
Evaluation of the efficacy of the additives Penetron Admix and Penetron in porous and cracked concretes (first
test series) C) Effect of Penetron treatment on the surface of structures of low porosity, cracked concrete; ENCO
Laboratory, Italy, 2005
Page | 20
Figure 23 Excerpt: Permeability results of cracked concrete samples treated with Penetron
The surface treatment with Penetron on the cracked test piece totally restored the water
tightness, even improving the performance compared to the untreated, undamaged control
samples.
In a test performed at OFI laboratories in Vienna, Austria9 test cubes containing horizontal
joints were treated with a Penetron coating. An additional layer of 25mm concrete was
casted onto the Penetron coating (see figure 34). The samples were then subjected to a
water pressure of 7 bar. The results showed that the water penetration into the untreated
25mm top layer only measured 22mm. Due to the crystal growth in the added, upper
concrete layer the penetrating water was stopped 3mm before reaching the actual Penetron
layer.
Figure 24 OFI sample set-up (Penetron “sandwich-system”)
9
Water penetration of concrete specimen treated with “Penetron” following OENORM B 3303, 2002-09-01; Test
Report No.: 303.897-1; OFI Technologie & Innovation GmbH, Vienna, Austria, 2005
Page | 21
3.2.7. Increase in compressive strength
When applying Penetron (especially Penetron Admix) a denser mass of the concrete is
created by sealing all capillaries and voids with insoluble crystal formations. This usually
results in an increase in the compressive strength of the treated concrete.
Tests performed at the University of New South Wales10 in Australia showed that Penetron
Admix-treated samples (1% by weight of cement) significantly increased the compressive
strength compared to the control samples.
Below are the detailed results obtained in this test campaign according to the Australian
Standard AS1012.9:
Concrete Age (day)
3
7
28
91
Compressive Strength (MPa)
Mix-P
Mix-C
(Penetron Admix)
(control sample)
23.0
16.7
31.4
24.2
42.5
33.2
46.8
38.2
Ratio of Mix-P
to Mix-C
1.37
1.30
1.28
1.22
The compressive strength of the Mix-P was 1.22 to 1.37 times of that of the control Mix-C at
ages between 3 days to 91 days despite the slump of Mix-P (130mm) being much higher
than that of Mix-C (80mm). It was apparent that the use of the Penetron Admix in concrete
significantly increased the concrete strength. The increase in compressive strength by the
Penetron Admix was proportionately greater at the early ages of 3 and 7 days. An important
benefit of the rapid early strength gain is permit striping of formwork earlier and to speed up
the construction process.
The increase in compressive strength depends to a great extend on the porosity of the
concrete. In more porous types of concrete the increase in compressive strength is usually
expected to be higher than in more dense types of concrete. As such the change in
compressive strength varies between different types of concrete. In any case Penetron
products will not negatively affect the compressive strength of the concrete.
3.2.8. Resistance against high water pressure
Penetron products effectively seal concrete pores, capillaries and microcracks and make
them impermeable against water ingress and chemical attacks. Penetron protects concrete
structures in under extreme conditions and waterproofs concrete even against high
hydrostatic pressures.
10
The Australian Centre for Construction Innovation University of New South Wales: “Properties of type GP
cement concrete modified with Penetron Admix”; ACCI Ref.No. 58324, 2002
Page | 22
A test executed at the IPT Laboratories in Sao Paulo, Brazil11 examined the water
penetration of water under pressure into porous Penetron Admix-treated concrete samples
(20MPa, w/c=0.54, 1% Penetron Admix by weight of cement) according to Brazilian
Standard NBR 10.787/94.
The concrete samples were casted and cured in water for 28 days.
Water pressures were applied over the period of one week:
Day 1-2:
Day 3:
Day 4-7:
0.1 MPa (1 bar)
0.3 MPa (3 bar)
0.7 MPa (7 bar)
After the first week the water penetration into the sample was observed. The sample was
then dried and the test repeated for a second, third and fourth week. After four weeks of
applied water pressures of up to 7 bar all microcracks, pores and capillaries had been
sealed by Penetron Admix and no further water was able to penetrate into the samples.
11
Penetration of water under pressure; Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, Brazil, 2007
Page | 23
After one week of water pressure a water
penetration of approximately 75% into the
sample can be observed. This is possible,
because the crystals in the sample have not
fully formed yet. The water in the capillaries
is used to grow the crystals further.
After two weeks a significant reduction in the
water penetration can be noticed with the
crystals continue to form inside the concrete.
After the third week, the water penetration
into the sample has decreased again by
almost 50% compared to the results of the
week before.
After the fourth week of applied water
pressure no water is able to penetrate into
the capillaries of the Penetron Admix treated
concrete. The crystals have now formed
completely and sealed the concrete
withstanding the water pressure.
The above test shows Penetron Admix-treated concrete completely dry under hydrostatic
pressures of up to 7 bar. A test campaign at the University of Bologna12, Italy in 2005 tested
Penetron Admix against a water pressure of 2000 kPa (20 bar). The Penetron-treated
sample shows significant reduction the permeability (water penetration) compared to the
control sample.
12
Determination of the water absorption at atmospheric pressure and under pressure of a total of 42 cylindrical
concrete test pieces at the Laboratorio del Consorzio Cave (Quarry Consortium Laboratory) of Bologna;
University of Bologna – Department of Earth, Geological and Environmental Sciences, Italy, 2005
Page | 24
Figure 25 Excerpt: Test results for Penetron Admix under 20 bar head water pressure, University of
Bologna, Italy, 2005
The possibility to withstand high hydrostatic pressure makes Penetron Admix an effective
solution for concrete structures such as hydroelectric dams, large water tanks, sea walls,
tunnels, etc.
3.2.9. Chemical resistance
Penetron not only effectively waterproofs concrete structures, but also protects concrete
against chemical attacks of various chemicals with a pH range from 3-11.
Accordant tests were undertaken at the University of Bologna13, Italy where Penetron-Admix
treated concrete samples were exposed to various chemical solutions including diluted
hydrogen chloride (HCldil), diluted sulfuric acid (H2SO4dil), a combination of the former,
calcium chloride (CaCl2) and sodium hydroxide (NaOH).
For this test on April 4, 2005 ten (10) cylindrical concrete test pieces, divided into two
batches, each consisting of 5 pieces, were prepared.
1st batch: ―Concrete B‖: defined as white, i.e. concrete made without adding Penetron Admix
2nd batch: ―Concrete PA‖: defined as concrete made adding Penetron Admix in percentages
of 2% by weight of the cement.
Both control and treated concrete samples had a w/c = 0.45.
13
Verification of resistance to chemical attack on ten (10) cylindrical concrete test pieces at the Laboratorio del
Consorzio Cave (Quarry Consortium Laboratory) of Bologna; University of Bologna – Department of Earth,
Geological and Environmental Sciences, Italy, 2005
Page | 25
The concrete to be tested was prepared at the Laboratorio del Consorzio Cave (Quarry
Consortium Laboratory) of Bologna and cured there for 28 days in a climatic test chamber at
20 ± 2°C and RH 95% ±3 RH. They were then conditioned in air with RH of 65% ±3 at a
temperature of 20 ± 2°C until a constant density was reached, evaluated by 2 weighing
cycles carried out at 24-hour intervals and with a difference in density inferior to 0.1%.
The laboratory wanted to verify the resistance to chemical attack of these samples using
solutions containing different hydrogen ion concentrations according to test standard UNI
7928 and 8019. Observations were carried out after 7 and 28 days of exposure.
Figure 26 University of Bologna: Chemical resistance test - Test set up
For the visual evaluation of chemical resistance standard UNI EN ISO 10545 -13/7
―Determination of chemical resistance – unglazed tiles‖ was applied.
As the table below shows Penetron Admix treated concrete did not permit any of the tested
solutions to penetrate into its surface. The samples resisted all solutions with a pH value
between 3 and 11 in constant contact and improved the condition of the samples in contact
with diluted hydrogen chloride (HCldil), diluted sulfuric acid (H2SO4dil), a combination of both
diluted hydrogen chloride and diluted sulfuric acid, where penetration into the surface was
observed at the control sample.
Page | 26
Figure 27 University of Bologna: Chemical resistance test - results
Due to its chemical resistance Penetron is protecting the concrete structures of various
projects around the world involving contaminated waters, such as sewage treatment and
waste water treatment plants, chemical storage tanks.
Page | 27
Figure 28 Milan South Waste Water Treatment
Plant, Italy
Figure 29 SABESP Sewage Treatment Plant, Brazil
3.2.10. Resistance to freeze-thaw cycles
One major factor for deterioration of exposed concrete structures in cold climates (such as
concrete bridges, roads, etc.) is the continuous freezing and thawing of concrete. Over time
freeze-thaw cycles will increase the permeability and allow corrosive agents to penetrate
resulting in corrosion damage and leading up to the failure of the structure. Freeze-thawcycles directly affect the durability of concrete.
Independent tests undertaken at Sor Testing Laboratories14 show a significant reduction of
weight loss of Penetron-Admix treated concrete compared to the control sample.
The treated concrete contained 16% fly ash and Penetron Admix was dosed at 1% by weight
of cementitious materials (cement and fly ash). The control sample consisted of plain
concrete without Penetron Admix.
The specimens were then subjected to a 3% sodium chloride solution in 25 cycles of freezethaw (according to the New York Department of Transportation Method 502-3P).
Mix I.D.
No. 1 – Control
No. 2 – Penetron Treated
(*) Average of duplicate specimens
Average % Weight Loss (*)
4.97
0.74
3.2.11. Compatibility with commonly-used concrete mix designs (Penetron Admix)
Penetron Admix has been specified and performed in numerous concrete mix formulations
around the world. It can be applied to any commonly-used concrete mix in today’s
construction industry. Penetron Admix does not have any known incompatibilities with other
14
Laboratory Tests of Penetron Admix in Concrete, Sor Testing Laboratories, Inc., USA Report No. 05-4070A,
2005
Page | 28
workability-enhancing admixtures, such as retarders or superplastizicers. There are no
limitations in regards to the water/cement ratio of the concrete to be treated.
Penetron Admix treated concrete can contain Portland cement-substitutes such as
pozzolans, fly-ash, slag, silica fume and similar. The crystal reaction in these types of
concrete will still take place as Penetron Admix, being a Portland cement-based product,
contains the reactive ingredients needed for its reaction to develop crystals in the
microcracks and capillaries.
3.2.12. Prevention of Alkali-Silica-Reaction (ASR)
As discussed in chapter 2.4., alkali-silica-reaction (ASR) can significantly reduce the
durability and strength of concrete. Concrete designers need to limit the alkali content of the
mix by selecting the right type of cement and non-reactive aggregates.
A simpler way to reduce the risk of ASR is to incorporate a mature crystalline admixture,
such as Penetron Admix, into the concrete mix. This will ensure the concrete is waterproofed
in-depth and deny the ASR the necessary water for the reaction to take place. Penetron
Admix has shown in a test at the MFPA-Leipzig, Germany15 that cracks will self-heal upon
when presented with water. Many other tests have proven the ability of Penetron crystals to
waterproof the capillary structure inside concrete. Further, Penetron Admix is certified by the
MPA Stuttgart, Germany16 to correspond to DIN V 18998 and as such has no negative
influence on the embedded steel.
3.2.13. Limitations
Despite the large number of benefits of crystalline waterproofing systems a few concerns
need to be given to the limitations of the performance of this system:
Insufficient surface preparation (coating application)
When Penetron is applied as a surface coating, a thorough surface preparation including
the repair of all cracks larger than 0.4mm, faulty concrete (such as honeycombs, form-tie
holes, etc.), the cleaning of the surface (in in order to dampen and roughen the surface and
to ensure an ―open-capillary-system‖) is key to a successful application of crystalline
waterproofing systems that are applied by brush or spray.
3.2.13.1.
Cold joints
15
MFPA Leipzig GmbH, Germany – Department of Structural Engineering: “Application-technology tests on
concrete test specimens with and without adding the sealing agent Penetron Admix (May 31, 2007)”
16
MPA Stuttgart Otto-Graf Institute, University of Stuttgart, Germany: “Electro-chemical tests of a concrete
admixture (Penetron Admix) according to DIN V 18998: 2002-11”, 2007
Page | 29
Cold joints can be considered as artificial cracks. The widths and voids in cold joints can
exceed those of a usual concrete capillary or microcracks and therefore need to be treated
separately either with a crystalline repair system (Penecrete/Penetron) or Penebar SW
waterstops.
3.2.13.2.
Active leaks
Active leakage (through cracks) needs to be stopped prior to application and repaired
separately with the Penetron repair system (Peneplug, Penecrete, Penetron Inject).
3.2.13.3.
Concrete defects
Concrete defects such as honeycombs, form-tie holes, etc. lead to voids in the concrete that
are beyond the width of a usual capillary or microcracks and therefore need to be repaired
separately with the Penetron repair system.
3.2.13.4.
Structural cracks
Structural cracks are cracks with a width larger than 0.4mm and therefore need to be
repaired either prior to the application of Penetron as a coating system or after application
(Penetron Admix) if they do not seal up after an observation period of 4-6 weeks.
3.2.13.5.
Exposed concrete structures (thermal cracks)
Penetron is not recommended as a stand-alone solution for directly exposed concrete
structures. Thermal cracks are a result of concrete directly exposed to high, sudden
temperature differences (e.g. expansion of the concrete exposed to extreme heat during
daytime, which contracts as a result of falling and cooler temperatures during night time).
This may lead to movement within cracks and crack widths of up to >2mm. Penetron crystals
are rigid and are not designed to compensate for such kind of movement in cracks.
Page | 30
4. At one glance - Benefit overview
System benefits
 Increases the durability of concrete
 Protects concrete for a lifetime
(permanent application)
 Provides a ―self-healing‖ concrete
(self-heals cracks up to 0.4mm)
 Resistance to high hydrostatic
pressure (20 bar)
 Increases compressive strength
 Resists chemical attack (pH 3-11)
 Reduces chloride penetration and
carbonation
 Prevents Alkali-Silica-Reaction (ASR)
 Prevents reinforcement steel from
corrosion
 Non-toxic (potable water approved)
 Green product (contains zero VOC)
 Can be used with any commonly
used mix design (no limitations
towards w/c ratio or cement content)*
 Low dosage rates (0.8% by weight of
cement)*
 Ease/versatility of application
 Protection remains intact when
surface is damaged
 Does not require any other form of
waterproofing or additional protection
of the system
 Allows concrete to ―breathe‖
 Penetrates deeply into the concrete**
 Can be applied from the positive or
negative side**
 Can be applied to moist or green
concrete**
 Compatible with glues and surface
coatings**
 Internationally renowned
waterproofing brand with extensive
track record (proven system)
*Penetron Admix / **Penetron/Penetron Plus
Benefits to property owners/contractors
 Provides time and cost savings on
projects
 Cost effective
 Permanent waterproofing system
 No maintenance
 Increases the quality of the concrete
for structural performance and
integrity
 Increases usage of infrastructure
 Eliminates down-time and costs
associated with maintenance and
repairs
 Unmatched technical support
 Reduces application errors
associated with installation of other
systems
 Improves pouring and placement of
concrete
 Contributes to LEED projects (accrual
of green points)
Page | 31
5. Comparison of Penetron products with other waterproofing systems
Description
Penetron/
Penetron Plus
Cementitiousbased chemical
that will penetrate
surfaces to form
insoluble crystal
formations deep
inside the
capillaries and
voids of concrete
Resistance to
hydrostatic
water pressure
 Improves with
time
 Tested of up to
16 bar head
water pressure
Protection of
reinforcement
steel
 Prevents
corrosion by
stopping passage
of penetrating
water, chlorides
and other
corrosive agents
Crack selfhealing ability
 Will re-activate in
the presence of
moisture to seal
new cracks even
years after
application
Crack
resistance
 Rigid material,
cannot withstand
excessive
transformation,
but self-heals
cracks of up to
0.4mm
Freeze/thaw
durability
 Improves
durability by
preventing water
ingress through
cracks and pores
Penetron
Admix
Cementitious
admixture
added to the
concrete at the
time of
batching to
form insoluble
crystals
throughout the
capillary
system of
concrete
 Improves
with time
 Continuous
self-healing
ability
 Initiates full
hydration
 Permanent
protection
 Prevents
penetration
of water,
chlorides
and other
corrosive
agents
 Will reactivate in
the presence
of moisture
to seal new
cracks even
years after
application
 Reduces
cracking in
plastic and
curing stage
 Self-heals
cracks of up
to 0.4mm in
the
presence of
moisture
 Improves
durability by
preventing
water
ingress
through
cracks and
pores
Membranes
(Positive side)
Liquid and sheet
applied bitumen and
polymers affixed to
the concrete surface
to form a barrier
against water
ingress
Other surface
applied Products
Materials applied to
the concrete surface
containing mainly
water repellents and
sealants
 Protection
breached by any
pinhole or seam
 Will require
replacement once
leaking
 Reduces initial
absorption, but will
deteriorate over
time
 Limited resistance
to hydrostatic
pressure
 No negative side
protection
 Limited protection
especially under
higher water
pressure
 No negative side
protection
 Prone to leak at
joints and seams
 No self-healing
ability
 No self-healing
ability
 Can withstand
excessive
transformation
 Deteriorating over
time (loss of
protection)Concret
e ―unprotected‖ if
leaks occur
 No durability at
crack locations
 Deteriorating over
time (loss of
protection)
 Deteriorating over
time (loss of
protection)Concret
e ―unprotected‖ if
leaks occur
 Deteriorating over
time (loss of
protection)Concre
te ―unprotected‖ if
leaks occur
Page | 32
Repair
requirements
 Easily repaired
from positive or
negative side (if
required)
Application
 Applied by
 Added to the
brush/spray
concrete at
onto positive or
the time of
negative side of
batching
old/new
 No additional
concrete
application
 Dry-shake
required
application onto
horizontal,
freshly placed
concrete
 Needs coarse,
 No surface
water saturated,
preparation
clean surface
with an ―opencapillary
system‖ for
brush or spray
application
 No surface
preparation for
dry-shake
application
 Can be applied
 Added to
during concrete
fresh
finishing or
concrete at
anytime after
the time of
batching
 Saves up to
50% time
and
construction
costs
 Not required
 Not required
Surface
preparation
Construction
schedule
Sub-surface
drainage
system
Additional
coatings
 Can be finished
with coating,
tiles, etc.
Maintenance
 Not required
 Easily
repaired
from positive
or negative
side (if
required)
 Does not
affect
coatings
 Adhesion
excellent for
coatings of
tiles
 Repairs
might be
required
once in the
case of
 Difficult to repair
 Difficult to identify
problem areas
 May require total
removal and
repair
 Expensive and
sometimes
impossible due to
accessibility
 Liquids: brush or
spray application
 Sheets: glued,
welded or
torched to the
concrete surface
 Correct
joints/seams
application
critical to
performance
 Clean surface
 Dry surface
 Smooth surface
 Repairs may
require removal
of previous
materials
 Must be applied
after completion
of structural work
 Requires
protective
cement mortar
 Some materials
require 28 days
cured concrete
for application
 Similar
scheduling as
membranes
 Might require
drainage under
high hydrostatic
pressure
 Require
protective
mortars prior to
finishes
 Requires
drainage under
high hydrostatic
pressure
 May require
special
preparation prior
to finishes
 Costly
replacement
generally
required
 Re-application
required under
high hydrostatic
conditions
 Only applied to
positive side
 Substrate profile
critical to
performance
 Needs surface
preparation
depending on
product
requirements
Page | 33
Service life
 Permanent and
improves with
time
structural
cracks of
concrete
defects after
application
 Permanent;
self-healing
of new
cracks even
years after
application
 Deteriorating
over time
 Damages during
backfilling,
plumbing
 Surface damage
will result in loss
of protection
 Best when first
applied
 Deteriorate over
time
 Vulnerable to
surface damage
5.1. Comparison between Penetron and hydrophobic pore blockers
Penetron
Pore blockers
Allows concrete to breathe, vapor to escape
the structure
Does not let concrete breathe, allowing vapor
pressure build up
High performance waterproofing product
designed to resist high hydrostatic pressure
proven up to 16 Bar
Good for damp proofing or water splash resistance
with low hydrostatic water pressure resistance up to
1.4 Bar
Does not affect the heat resistance of the
concrete and will only increase it
Due to bituminous nature of these products, their
effect on the heat resistance of the concrete should
be investigated before use
Does not negatively affect the hydration
process of the concrete
Completely stops water movement within concrete,
as such internal self-desiccation may occur or
imbibing water cannot enter.
In both cases a portion of cement cannot be
hydrated completely
Penetron dramatically increases the
autogenous healing ability of concrete
May decrease the autogenous healing capacity of
concrete. This should be investigated before use
Increases compressive strength of concrete
Effect of these products on initial and final strength
of concrete should be investigated before use
Does not affect the amount of reinforcement
steel specified
May require additional reinforcement steel
Does not affect the setting time of the concrete
when specified properly
Effects on the setting time of concrete need to be
investigated before use
Provides chemical, carbonation, sulfates,
chloride etc. protection
Resistance against chemical attack should be
investigated before use
Does not negatively affect the performance of
Construction joints will require special treatment to
Page | 34
construction joints
break the water- repellent effect of these products
Low dosage of 0.8% of cement contents in the
mix will suffice
Very high dosage required to reach their effect
Economical solution
Usually very expensive solution, partly because of
high dosage required
Works very effectively even on low strength
concrete
A minimum of 350 kg of cement is required for these
products to be effective, Water / cement ratio and
slump need to be tightly controlled to comply with
manufacturer’s published limitations
Self heals cracks of 0.4mm and more
throughout the life of the concrete
Blocks pores passively, no known self healing effect
on concrete
Will reactivate after many years if new cracks
develop to stop leaks
No reactions
Long term effects on concrete have been
proven over 24 years
Long term effects on concrete should be
investigated before use
6. Application instructions – Penetron Admix
6.1. Description
Penetron Admix (integral crystalline waterproofing admixture) is added to the concrete mix at
the time of batching. Penetron Admix consists of Portland cement, very fine treated silica
sand and various active, proprietary chemicals. These active chemicals react with the
moisture in fresh concrete with the by-products of cement hydration to cause a catalytic
reaction, which generates a non-soluble crystalline formation throughout the pores and
capillary tracts of the concrete. Thus the concrete becomes permanently sealed against the
penetration of water or liquids from any direction. The concrete is also protected from
deterioration due to harsh environmental conditions.
Note
The Penetron Admix has been specially formulated to meet varying project and temperature
conditions (see Setting Time and Strength). Consult with a Penetron Technical
Representative for the most appropriate Penetron Admix for your project.
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6.2. Dosage Rate
Penetron Admix: 0.8% by weight of cementitious materials minimum. Consult with
Penetron’s Technical Department for assistance in determining the appropriate dosage rate
and for further information regarding enhanced chemical resistance, optimum concrete
performance, or meeting the specific requirements and conditions of your project.
6.3. Mixing
Penetron Admix must be added to the concrete at the time of batching. The sequence of
procedures for addition will vary according to the type of batch plant operation and
equipment. Following are some typical mixing guidelines.
6.3.1. Ready Mix Plant – Dry Batch Operation
Add Penetron Admix in powder form to the drum of the ready-mix truck. Drive the truck
under the batch plant and add 60% - 70% of the required water along with 300-500 lbs (136227 kg) of aggregate. Mix the materials for 2-3 minutes to ensure the Admix is distributed
evenly throughout the mix water. Add the balance of materials to the read-mix truck in
accordance with standard batch practices.
6.3.2. Ready Mix Plant - Central Mix Operation
Mix Penetron Admix with water to form a very thin slurry (e.g. 40 lbs (18 kg) of powder mixed
with 6 gallons (22.7 l) of water). Pour the required amount of material into the drum of the
ready-mix truck. The aggregate, cement and water should be batched and mixed in the plant
in accordance with standard practices (taking into account the quantity of water that has
already been placed in the ready-mix truck). Pour the concrete into the truck and mix for at
least 5 minutes to ensure even distribution of the Penetron Admix throughout the concrete.
6.3.3. Precast Batch Plant
Add Penetron Admix to the rock and sand, then mix thoroughly for 2-3 minutes before
adding the cement and water. The total concrete mass should be blended using standard
practices.
Note
It is important to obtain a homogeneous mixture of Penetron Admix with the concrete.
Therefore, do not add dry Admix powder directly to wet concrete as this may cause clumping
and thorough dispersion will not occur. For further information regarding the proper use of
Penetron Admix for a specific project, consult with a Penetron Technical Representative.
6.3.4. Technical Services
For more instructions, alternative application methods, or information concerning the
compatibility of the Penetron treatment with other products or technologies, contact the
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Technical Department of ICS Penetron International Ltd. or your local Penetron
Representative.
6.4. Setting time and strength
The setting time of concrete is affected by the chemical and physical composition of
ingredients, temperature of the concrete and climatic conditions. Retardation of set may
occur when using Penetron Admix. The amount of retardation will depend upon the concrete
mix design and the dosage rate of the Admix. However, under normal conditions, the Admix
will provide a normal set concrete. Concrete containing Penetron Admix may develop higher
ultimate strengths than plain concrete. Trial mixes should be carried out under project
conditions to determine setting time and strength of the concrete.
6.5. Limitations
When incorporating Penetron Admix, the temperature of the concrete mix should be above
40°F (4°C).
7. Application instructions – Penetron
7.1. Description
Penetron is a surface-applied, integral crystalline waterproofing material, which waterproofs
and protects concrete in-depth. It consists of Portland cement, specially treated quartz sand
and a compound of active chemicals. Penetron needs only to be mixed with water prior to
application.
When Penetron is applied to a concrete surface the active chemicals combine with the free
lime and moisture present in the capillary tracts of the concrete to form an insoluble,
crystalline structure. These crystals fill the pores and minor shrinkage cracks in the concrete
to prevent any further water ingress (even under pressure). However, the Penetron will still
allow the passage of vapor through the structure (i.e. the concrete will be able to ―breathe‖).
In addition to waterproofing the structure, Penetron protects concrete against seawater,
wastewater, aggressive ground water and many other aggressive chemical solutions.
Penetron is approved for use in contact with potable water, and is therefore suitable for use
in water storage tanks, reservoirs, water treatment plants…etc. Penetron is not a decorative
material.
7.2. Consumption
Water retaining structures, internal concrete wall surfaces: Two coats of Penetron at 1.251.5 lb/sy
(0.7-0.8 kg/m²) or one coat at 2.5 - 3 lb/sy (1.4-1.6 kg/m²) applied with brush or spray.
7.2.1. Construction slabs
Penetron at 2 lb/sy (1.1 kg/m²) applied in one slurry coat to hardened concrete or dry
sprinkled and trowel applied to fresh concrete when this has reached initial set.
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7.2.2. Construction joints
Penetron at 3 lb/sy (1.7 kg/m²) applied in slurry or dry powder consistency immediately prior
to placing the next lift/bay of concrete. Alternatively Penebar SW type waterstops can be
applied.
7.2.3. Blinding concrete
Penetron at 2.5 lb/sy (1.4 kg/m²) applied in slurry or dry powder consistency immediately
prior to placing the overlying concrete slab.
7.3. Surface Preparation
All concrete to be treated with Penetron integral crystalline waterproofing must be clean and
have an ―open‖capillary system. Remove laitance, dirt, grease, etc. by means of high
pressure water jetting, wet sandblasting or wire brushing. Faulty concrete in the form of
cracks, honeycombing, etc. must be chased out, treated with Penetron and filled flush with
Penetron Mortar. Surfaces must be carefully pre-watered prior to the Penetron application.
The concrete surface must be damp but not wet.
7.4. Mixing
Penetron is mechanically mixed with clean water to a creamy consistency or that resembling
thick oil. Approximate mixing ratio is 2 parts water to 5 parts Penetron powder (by volume).
Mix only as much material as can be used within 20 minutes and stir mixture frequently. If
the mixture starts to set do not add more water, simply re-stir to restore workability.
7.5. Application
7.5.1. Slurry consistency
Apply Penetron in one or two coats according to specification by masonry brush or
appropriate power spray equipment. When two coats are specified apply the second coat
while the first coat is still ―green‖.
7.5.2. Dry powder consistency (for horizontal surface only)
The specified amount of Penetron is distributed in powder form through a sieve and troweled
into the freshly placed concrete once this has reached initial set.
7.6. Post treatment
The treated areas should be kept damp for a period of five days and must be protected
against direct sun, wind and frost, by covering with polyethythene sheeting, damp burlap or
similar.
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Note
Do not apply Penetron at temperatures at or below freezing. Penetron cannot be used as an
additive to concrete or plasters. (Penetron Admix should be considered for these
applications).
8. Application instructions – Penetron Plus
8.1. Description
Penetron Plus is a unique integral crystalline chemical treatment for the waterproofing and
protection of concrete. Penetron Plus has been specially formulated for dry-shake
applications on horizontal concrete surfaces where greater impact and abrasion resistance is
required. Packaged in the form of a dry powder compound, Penetron Plus consists of
Portland cement, various active proprietary chemicals, and a synthetic aggregate hardener
that has been crushed and graded to particle sizes suitable for concrete floors. Penetron
Plus becomes an integral part of the concrete surface thereby eliminating problems normally
associated with coatings (e.g. scaling, dusting, flaking and delamination).The active
chemicals react with the moisture in the fresh concrete causing a catalytic reaction, which
generates a non-soluble crystalline formation within the pores and capillary tracts of the
concrete.
8.2. Coverage
Under normal conditions, the coverage rate for Penetron Plus is 1 lb per sq yard (0.6 kg per
m²), depending on the degree of abrasion resistance required.
Note
Under heavy traffic conditions or where even greater abrasion resistance is required, consult
a Penetron Technical Representative for a recommendation that meets your specific needs.
8.3. Application Procedures
1. Fresh concrete is placed, consolidated and leveled.
2. Wait until concrete can be walked on leaving an indentation of 1/4‖–1/3‖ (6-9 mm).
Concrete should be free of bleed water and be able to support the weight of a power trowel.
Then, float open the surface.
3. Immediately after floating open the surface, apply one-half of the dry shake material by
hand or mechanical spreader. The dry shake material must be spread evenly.
4. As soon as the dry shake material has absorbed moisture from the base slab, it should be
power floated to the surface.
5. Immediately after power floating, apply remaining dry shake material at right angles to the
first application.
6. Allow remaining dry shake material to absorb moisture from the base slab and then power
float the material into the surface.
7. When concrete has hardened sufficiently, power trowel surface to the required finish.
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8.4. Curing
Curing is important and should begin as soon as final set has occurred but before surface
starts to dry. Conventional moist curing procedures such as water spray, wet burlap or
plastic covers may be used. Curing should continue for at least 48 hours. In hot, dry sunny
conditions consult manufacturer for specific instructions. In lieu of moist curing, concrete
sealers and curing compounds meeting ASTM C-309 may be used.
Note
It is common that edges of a slab wall will set up earlier than the main body of concrete.
Such edge areas can be dry-shaked and finished with hand tools prior to proceeding with
application of the main body of concrete.
For the best results when applying dry shake materials, the air content of the concrete
should not exceed 3% (a high air content can make it difficult to achieve a proper
application). If a high entrained air content is specified (e.g. for concrete that will be exposed
to freezing and thawing), contact the Technical Department of Penetron International Ltd. for
further application information.
In hot, dry, or windy conditions, it is advisable to use an evaporation retardant on the fresh
concrete surface to prevent premature drying of the slab. Chronic moving cracks or joints will
require a suitable flexible sealant.
For certain concrete mix designs, we recommend a test panel be produced and evaluated
for finishing. (For example, high performance concrete with a low water/cement ratio, air
entrainment, super plasticizers, or silica fume may reduce bleed water and make the
concrete more difficult to finish).
8.5. Technical Services
For more instructions, alternative application methods, or information concerning the
compatibility of the Penetron treatment with other products or technologies, contact the
Technical Department of Penetron International Ltd. or your local Penetron representative.
9. Contact and Disclaimer
Penetron products are exclusively manufactured by ICS Penetron International Limited
located at 45 Research Way, Suite 203, East Setauket, NY 11733, USA.
Penetron products are distributed and applied through a global network of authorized
distributors and trained applicators. Please consult with a Penetron representative prior to
using and applying Penetron products for technical assistance and support.
All referenced test reports in this document are available on request from ICS Penetron
International Ltd.
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