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Ensuring the effectiveness of repair and protection of the marine
hydrotechnical structures using PCC
Grzegorz Adamczewski1, Paweł Łukowski
1, Krzysztof Saramowicz
1, Piotr Woyciechowski
1
1Warsaw Universit of technology, Warsaw,Poland, [email protected]
2 Warsaw Universit of technology, Warsaw,Poland, [email protected]
3 Warsaw Universit of technology, Warsaw,Poland, [email protected]
4 Premix Sp. Z o.o., Połaniec, Polska, [email protected]
Abstract
The article presents the general classification of marine hydrotechnical constructions
and in particular the technical characteristisc of hydrotechnical constructions and their impact
on the durability. Hazards in the typical conditions of environment of hydrotechnical
constructions were identified. The basic principles of repair design in the light of the PN-EN
1504 series of standards and the use of modern repair materials with particular emphasis on
polymer-cement materials are discussed. In addition, there are examples of repairs designed
and implemented in accordance with the most current principles of the construction industry,
taking into account the specificity of modern repair materials.
Keywords: durability, PCC, hydrotechnical structures, repair
1. Characteristics of marine hydrotechnical structures
All engineering and communication structures, hydrotechnical inland and marine
structures as well as municipal and municipal buildings, including water and sewage facilities,
are exposed to the permanent negative impact of the environments in which they operate. This
negative impact of the environment is manifested by corrosive destruction of various scales
and ranges, in each case this shortens the "lifetime" of the building.
The observed climate changes have been neglected for a longer time, increasing
concentrations of chemically aggressive substances, both in water and in the air, the state of
emergency is systematically deepening. In common assessment and practice, the degree of
threat to hydrotechnical constructions, both inland and marine, is particularly high. It is
caused mainly by plant protection chemicals, biologically active substances, biogenic sulfuric
acid and its derivatives, artificial fertilizers and in marine structures, salinity, organic and
inorganic substances, variable temperature, hydraulic interactions, etc.
Corrosive damage to buildings is the sum of destructive chemical and physical
processes and arise when the designed concrete protections cease to work (lagging,
impregnation, coating). The processes of destruction are inevitable and thermodynamically
determined to the state of energy minimum and the increase in entropy [1].
1.1 Characteristics of hydrotechnical structures and their durability
The applicable legal regulations for hydrotechnical sea constructions are as follows:
Regulation of the Minister of Transport and Maritime Economy of 01.06.1998 regarding
technical conditions to be met by marine hydrotechnical constructions and their location and
the regulation of the Minister of Maritime Economy of October 23, 2006 regarding technical
conditions use and detailed scope of control of marine hydro-technical buildings [6].
The concept of a naval building should be understood as an underwater or submersible
structure, which together with installations and technical equipment as well as other
equipment constitute a technical whole located at the location:
a.) in sea areas
b.) in the area of direct contact with sea areas - in the technical belt of the seacoast determined
in accordance with the Act of 21.03.1991 on maritime areas of the Republic of Poland and
maritime administration (Journal of Laws from 2003 No. 153, item 1502 as amended) in ports
and sea harbors.
The nautical buildings are: ports, sea harbors, swimming pools, wharfs, jetties,
outskirts, port and shore breakwaters, piers, steel and concrete dolphins, the aquatic part of the
naval buildings. The above-mentioned Ordinance specifies service life for the construction
and so on:
- port quays , piers and margins 60 years, max.100 years
- seawall and coastal breakwaters 60 years, max. 100 years
- decks and piers 45 years, max.100 years
- an aquatic part of sea buildings 30 years, max. 60 years
- steel and concrete dolphins 25 years.
The given periods of building durability constitute important marketing information
for the buildings being operated, as well as for designing and offering technological and
material solutions for the objects being designed and constructed.
1.2 Identification of environmental threats
There is no doubt that the basic observed causes of corrosive destruction of reinforced
concrete structures are: frost corrosion, chloride corrosion, biological corrosion and
carbonation. Under normal conditions, the concrete cover provides a protective barrier for
steel reinforcement. This obviously applies to both structures located in the marine
environment and those exposed to permanent de-icing solutions. This takes place when the
structure has been designed and constructed in accordance with modern standards (PN-EN
1992-1-1, PN-EN 13670 and PN-EN 206).
With regard to older structures, eg from the 70-80 of the last century, the standards
used at that time did not take into account the environmental impact to the extent required. In
many buildings from this period, the effects in the form of reduced reinforcement durability
are visible in Fig.1.
Fig. 1 Corrosion of the marine structure from the 70-80’s
Particularly dangerous circumstances include the so-called hidden corrosion of
reinforcement as a result of chloride ions. This corrosion often takes a long time without
visible effects. Of all the ions, chloride ions quickly penetrate deep into the cement matrix,
which is why the corrosion of concrete treated with chloride solution, eg from sea water
running at high speed. Chloride aggression and carbonation lead to a change in the pH of the
concrete and the formation of expansive compounds causing cracking of the concrete. An
equally dangerous effect of chloride ions is the corrosion of reinforcing steel. The condition
evaluation here is possible by electrochemical methods allowing to reveal corrosion of the
reinforcement even when there are no visible external signs. Factors affecting the penetration
of chlorides are: cyclic saturation and drying and the effect of frost, which leads min. for
exfoliating concrete cover. Apart from the discussion, the fact is that particularly exposed to
destructive phenomena caused by the action of chlorides from water and salt spray are piers,
breakwaters, dolphins, wharfs, piers and all other buildings in direct contact with sea basins.
The basic mechanism of the previously mentioned chloride destruction involves the
migration of an aqueous solution containing chloride ions deep into the structure, which leads
to a gradual "piercing" of the passive layer of the reinforcing steel. As a result, after the
destruction of the passive layer, on the surface of the steel arise areas with different potentials
between metal and electrolyte forming a pore liquid in concrete. Local corrosion cells are
formed, consisting of point cathodes and anodes. The effects of physical and chemical
processes lead to a systematic degradation of the structure and the loss of its technical design
features [2]. Significant threats to hydrotechnical naval structures are: variable liquid hight,
wave and storm, surface icing, salt mist, mechanical damage from flowing units, biological
contaminants (oils, greases, organic waste, etc.).
Corrosive effects of a similar nature are observed in inland hydrotechnical and
communication buildings. These are the results of various other ions, "winter actions" and
industrial pollution. This applies to min. buildings located in the so-called flowing waters
where phenomena of floating liquid column, cavitation, mechanical impacts from flowing
objects, ice, frazil and chemical impurities (detergents, biologically active agents, etc.) are
observed.
Fig. 2 Corrosion damage to the weir water intake
In communication structures, cumulative corrosion effects are observed on the
surfaces of supports and abutments in the zones of liquid splashing and beams under railings.
In all the buildings referred to above, there are places defined as critical, which are not usually
of a structural character, but the corrosion hazards intensify. These include, among others:
discontinuity of surface protection (detachment of coatings), secondary corrosion of the
"halo" effect, defective surface geometry, scratches and cracks, connection of steel elements
with concrete, steel and galvanized edging, anchoring structures, installation transitions, etc.
Selected examples such corrosion effects are shown in figure 3.
Fig. 3 Defective surface geometry and corrosion of the connection of steel elements with
concrete,
1.3 Usefulness and the applications of the PCC
Polymer-cement concretes are known and used for more than fifty years, but their
particularly intensive development has been observed in the last decade. The polymer added
to the Portland cement can co-operate with the cement binder. This causes significant changes
in both technological and use properties of the composite. The vast majority of these
properties is improved, some very significant (tensile and flexural strength, adhesion to the
substrate, tightness).
Very good properties of the materials with polymer-cement binders are the reason for
their growing use. The main area of using is repairing and anti-corrosion protection, as well as
roads and bridges pavements and overlays, industrial floors and pre-cast elements.
The polymer-cement composites remain the subject of the interest of researchers, as
many problems from that range are still not resolved. This refers, particularly, to the
mechanisms of cement matrix modification by polymers and directions of changes of the
material properties, caused by that modification. Also, new types of polymer-cement
composites are proposed, and the range of their use is still enlarged [15].
2. Repair design according to the PN-EN 1504
The growing scale of corrosion damage of the previously mentioned types of
engineering, engineering and communal structures caused a serious interest in the second half
of the last century. As a result, the problem of counteracting the negative effects of corrosive
effects on reinforced concrete structures, starting from design and ending with the
construction of the building, has been met with significant regulations in the scope of repair
strategies and their corrosion protection. In 2004-2013, a 10-part European standard EN-1504
was developed under the title "Products and systems for protection and repair of concrete
structures." Definitions, requirements, quality control and conformity assessment " [3], which
comprehensively ordered the methods of protection and repair of concrete structures. The
standard formulates principles and methods of conduct, established basic requirements for
appropriate systems and repair products as well as elements of the maintenance management
strategy.
Having knowledge about the requirements contained in the referenced standard
significantly facilitated the analysis of corrosion phenomena, the mechanisms of their
operation and counteracting their effects. Selection of the optimal technology and system of
repair materials with the use of documents: (construction and non-structural repairs PN-EN
1504: 3 [4] and concrete protection (surface protection PN-EN 1504: 2 [5] requires a
comprehensive analysis before making final decisions. With regard to hydro technical sea
structures, it has a special dimension due to their specific operating conditions and the
destructive mechanisms occurring there. The analysis should also take into account the
required dates of building life. The construction expected service life was specified previously
and determines the requirements for materials used in repairs and protection of their structure.
Undertaking the implementation of the building protection system or its repair requires
also taking into account the provisions contained in PN-EN 206: 2016-12 [7] regarding
environmental exposure classes together with intensity levels in which the building is or will
be constructed: XS-4- cyclically wet and dry, surfaces above and below the concrete surface;
XS-1- salt spray from sea water without contact with water - building elements covered with
salt spray; - XS-2- permanently submerged - elements of the building permanently below the
surface of the sea; XS-3 zone of tides and sprays of salt spray - building elements in the zone
of tides and continuous splashes and supply of salt spray;
XF-4 zone of strong water saturation with de-icing agents and sea water - building elements
above the water level, frozen and thawed in the zone of salt spray and seawater splash.
The sum of the facts presented earlier is an important premise in the selection and
development of effective material systems for repairs and corrosion protection of marine
hydro-technical buildings.
Theoretical studies and practice, analysis of required properties and the obtained
results indicate the desirability of using materials referred to as polymer concretes, or more
precisely, groups of products marked as PCC and PC materials. The scheme of polymer
cement concretes is shown in the figure. [4]
Fig. 4. Schematic representation of the material concept of polymer concretes:
PCC – Polymer-Cement Concretes, PIC – Polymer Impregnated Concretes,
PC – resin concretes
Materials (PCC-Polymer cement concrete and PC - Polymer concrete) are commonly
used in repairs of reinforced concrete structures and their surface protection.
Excellent adhesion to the substrate, tightness, frost resistance and resistance to a wide range
of environmental threats are their undeniable advantages.
It is of particular importance for the compatibility of the repaired (protected) and repaired
material to be properly selected for the PCC materials we intend to use. In any case, the
selection must ensure such a situation that possible damage occurs in the repaired concrete
foundation.
This article focuses on two applications of polymer-cement materials, namely, PCC
repair mortars and protective coatings based on them.
In pre-mix repair mortars and protective coatings - a polymer (copolymer) redispersible
powder obtained by evaporation from the dispersion is used. This powder, after mixing with
water, again forms a dispersion with a polymer content with a particle size of 1-10μm.
A number of polymers are used, most often copolymers, including styrene-acrylic
copolymer (for coating material) and butyl polyacrylate for repair mortars.
amorfic
amorfic:
crosslinked
amorfic:
quasi-
crystalline
CONCRETE PIC
PC
PCC
Monomers, oligomers,
pre-polymers, polymers
Portland cement Aggregate
In the case of PCC material with a polymerised modifier, its modifying effect is mainly of a
physicochemical nature. [9]
Most often, the coating material is obtained as an aqueous solution (emulsion) of the
aforementioned copolymer with an active filler in the form of Portland cement and synthetic
fibers and the repair material is a composite composed of a copolymer, Portland cement or
sulfate, microsilica colloidal, carefully selected aggregates with different granulation and
microfibers synthetic.
The polymer-cement microstructure, two interpenetrating polymer and cement networks
results in a series of specific and effective functional values. [10]
Obtained in this way, the coatings protect concrete surfaces against aggressive environmental
factors while allowing evaporation of water from concrete (breathing) and repair materials
(repair type mortars (PCC) effectively combine the substrate repaired with repair material
These materials are effective at low and variable temperatures, watertight, with high diffusion
resistance for carbon dioxide, resistant to chlorides, resistant to variable contact with water,
resistant to abrasion and mechanical impact. [10]
The above arguments constituted the main reasons for their use in repairs and protection of
the surface of maritime hydro-technical structures to meet the below-specified functions in
accordance with PN-EN 1504-9: 2010 [11] to: rebuilding a concrete element (Principle 3) by
manually applying a repair mortar (Method 3.1), applying a layer of concrete or mortar
(Method 3.2), spraying concrete or mortar (Method 3.3); reinforcing the structure (Principle
4) through the mortar or concrete overlay (Method 4.4); increasing the resistance to physical
factors (Principle 5) through mortar or concrete overlay (Method 5.3), resistance to chemical
agents (Principle 6) through mortar or concrete overlay (Method 6.3). Description of
principles and methods of electrochemical realkalisation of concrete, realiZation by diffusion,
changes in electrical resistance of the casing, electrochemical chloride removal and cathodic
protection methods. requires a separate study.
The use of polymer-cement materials according to the presented principles and methods
requires compliance both in repairing and protective operations strict rules of conduct,
including also maintaining good cooperation of the substrate with the applied composite. One
of the main conditions that guarantees the effect of applying materials is the proper
preparation of the substrate.
3. Repair materials
Polymer additives to Portland cement concrete have well established position [12]
among the modern building materials. The necessary condition of successful using is,
however, the proper selection of the type and amount of polymer.
Polymer-cement concretes (PCC) are obtained by adding polymer, oligomer or
monomer to the concrete mix. According to the chemical reactivity of the modifier, the PCC
can be categorised as follows:
- PCC polymerised after mixing (post-mix), in which the chemically active, chemosetting
synthetic resins (e.g. epoxies) or suitable monomers or pre-polymers are introduced into the
concrete mix; the polymerisation (in the case of the resins and pre-polymers the “further
polymerisation” – crosslinking) runs simultaneously with the hydration of Portland cement,
-PCC polymerised before mixing (pre-mix), in which the chemically inactive polymers
(e.g.styrene-butadiene latex) are introduced into the concrete mix; their modifying action has
mainly physical (physico-chemical) character.
Polymer can be introduced into the concrete mix in the various forms, as:
dispersion – two-phase system, in which the solid particles of very small size (200-1000
nm) are dispersed in the liquid phase. The water dispersions of polymers are often called
latexes. This is the most often used form of the polymer additive;
emulsion – a system consisting of two non-mixing liquids, in which the dispersed phase is
formed by micro-droplets (1000-5000 nm) of the liquid resins;
re-dispersible powder – a powder obtained by evaporation of the water from the dispersion;
after mixing with water, the powder forms the dispersion again; the size of the polymer
particles is usually larger and equal to 1-10 m;
water solutions of polymers;
The basic polymers used for production of PCC-premix are as follows:
- acrylic polymers – acrylic polyesters, PAE (polymethyl methacrylate, polyethyl acrylate,
polybuthyl acrylate),
- styrene-acrylic co-polymers, SAE,
- styrene-butadiene co-polymers, SB,
- polyvinyl acetate, PVA,
- co-polymers of vinyl acetate – ethylene, PVAE, and vinyl acetate – vinyl versenate,
VEOVA.
Epoxy resins are mainly used for production of PCC-postmix.
There are many various polymer dispersions and re-dispersible powders available on
the market, however, the opinion is often expressed that only 5% of them can be used in the
mixes with Portland cement [13]. The majority of those substances is not stable enough and
they coagulate already during mixing, forming polymer aggregates. The products destined to
the modification of concrete need stabilisation, usually by non-ionic surfactants. Moreover,
the products can contain anti-foaming admixtures and antiseptic means. The commercial
dispersions usually contain from 10% to 50% of the solid polymer.
The introduction of the polymer can cause de-colouring of concrete, particularly in the
case of styrene-butadiene co-polymers, SB. If the preserving of the colour of concrete is
important, the using of styrene-acrylic co-polymers, SAE, or polyacrylic esters, PAE, is
recommended.
The polyester modifiers can undergo the hydrolysis in the alkaline environment of the
cement paste. This is particularly dangerous in the case of polyvinyl acetate. Generally, the
use of that modifier is not recommended, except of the dry conditions of concrete using; in the
opposite case the worsening of the concrete tightness can take place instead of its
improvement. Co-polymers should be used in the wet conditions.
The polymers containing chloride substituents (e.g. polyvinylidene chloride) are not
allowed for concrete modification due to the possibility of releasing the chloride ions in the
alkaline environment of the cement paste. The released chlorides would cause the corrosion of
the reinforcing steel.
Generally, three main properties are considered when selecting the polymer modifier:
tightness, adhesion and chemical resistance. Additionally, the possible de-colouring of the
concrete is taken into consideration. If the aim is [13]:
- improvement of tightness and adhesion, and the possible de-colouring is not important, the
styrene-butadiene dispersions, SB, are preferred,
- improvement of tightness and adhesion with unchanged colour of the concrete, the styrene-
acrylic dispersions, SAE, or polyacrylic esters, PAE, are recommended. In some cases the co-
polymers of polyvinyl acetate can be accepted, however, the higher risk of de-colouring and –
in the wet zone – also the worsening of tightness can occur,
- improvement of tightness and chemical resistance to both acid and alkaline environment, the
epoxy resins are used. Introduction of the epoxy resin into the concrete causes, moreover,
increase of tensile strength and slight decrease of the modulus of elasticity,
- only improvement of adhesion in the dry conditions of use, polyvinyl acetate
(homopolymer) can be used.
Styrene-acrylic co-polymers (SAE), polyacrylic esters (PAE), ethylene-vinyl acetate
co-polymers (EVA), polyvinyl acetate (PAE) and co-polymers of vinyl acetate and vinyl
versenate (VEOVA) are available in the form of re-dispersible powders. Using of the
modifiers in the form of the powders is much more convenient, since it makes possible to
obtain the one-component polymer-cement “dry mixes”, however, it is also significantly more
expensive. The properties of the end product modified by re-dispersible powders, with the
same value of w/c and the same content of the solid polymer, are very similar to the properties
of the products modified by polymer dispersions.
The setting of the polymer-cement mixes in the case of PCC-premix consists in two
processes: hydration of cement and formation of continuous polymer film (coalescence)
resulting from “consumption” of water by the cement and its partial evaporation. In the case
of PCC-postmix, the additional chemical reaction between the resin and amine hardener takes
place, leading to spatial crosslinking of the polymer. The hydration and coalescence are
competitive processes. Premature formation of the polymer film hinders or even precludes the
cement hydration. The kinetics of those processes should be adjusted in such way that the
hydration precedes the coalescence. The water included in the polymer dispersion is always
taken into account while establishing the water-cement ratio, w/c, of the PCC mixes [15].
4. Examples of marine structures repairs done with PCC materials
The applications described below concerned three objects; the test area of the central-
entrance pier in the Naftoport of Gdańsk, the breakwaters of the eastern and western seaport
Dziwnowo, the breakwater of the internal sea port of Władysławowo.
The state of the surface of the objects referred to above, before starting the works are
presented below on figure 5 (6rom the left: Element of the breakwater Władysławowo,
element of the Dziwnow breakwater, fragment of the Naftoport pier). The Contractor, taking
into account the circumstances referred to above, commencing remedial works was aware of
the necessity of applying "methods and principles" in legal regulations and legal regulations
resulting from direct contact with the sea basin. The work was preceded by the assessment of
the degree of carbonation of the surface and the degree of its salinity, identification of
disintegration previously used synthetic linings, corrosion centers, scratches and cracks, and
in the case of a pier documenting the bottom condition for obtaining permission to perform
repair works using polymer-cement materials in the port basin.
In all three of the above-mentioned projects, similar work sequences were used.
Reasonable differences in the preparation phase of the substrate to obtain compatibility with
the repair materials were justified by the evaluation of their revisions. Generally, to remove
any degraded parts, a stream abrasive method was used - hydro monitoring at 200 bar
pressure (Sa 2.5 steel cleanliness effect was achieved) and additionally to obtain a guarantee
for cleaning the reinforcing steel eliminating any possible secondary corrosion - manual
cleaning.
Due to the risk of salt spray, and thus the possibility of corrosion centers on the
cleaned surface of reinforcing steel, immediately after cleaning, it was covered with a
polymeric-cement material containing a corrosion inhibitor. A material with the trade name
Prem Kor was used, which additionally fulfills the role of a tack bridge for repair materials.
All identified defects in the surface of the substrate were filled with PCC mortars with
different granulation of quartz filler. Materials with the MIX-1 trade name were filled with
cavities with a depth of more than 6.0 mm and depth below the MIX-2 material. The latter
fulfilled the function of a "putty" standardizing the geometry of the surface to be repaired to
minimize the possibility of salt deposition and the formation of efflorescence. After
completing the works referred to above, a coating of a polymer-cement material with
anticorrosive protective function under the trade name Prem Cem El was made using the
technological time interval.
The material is a composite composed of a redispersible copolymer, Portland cement,
a quartz filler with low grain size and the addition of synthetic microfibers. After the addition
of mixing water in a well-defined proportion, an aqueous suspension was prepared ready for
application. It is optimal to double the shell and obtain a thickness of 0.4 mm, it is possible to
multiply it to 3.0 mm.
During the work, all necessary environmental conditions (temperature, humidity, dew
point) of traction adhesion and bottom condition in the surface repairs of the pier were
performed. The intervals between the individual phases of the work were, for obvious
reasons, minimized.
The above-described technological activities fulfilled the requirements of repairs and
protection of the surface of reinforced concrete structures operating in the conditions specified
in the PN-EN 1504 and PN-EN 206 standards. The drawings of the surface of objects after the
completion of works are presented on figure 6. (From left: Element of the Władysławowo
breakwater, element of the Dziwnow breakwater, fragment of the Naftoport pier).
Fig. 5 Condition of the structure before the repair
Fig. 6 Condition of the structure after the repair with the PCC material
5. Conclusions
The working environment of hydrotechnical constructions is fundamentally different
from ordinary constructions. Environmental aggression causes in many cases a strong
corrosion of concrete and steel, which involves the need to carry out repairs. They should be
performed based on an analysis of the actual environmental impacts and recommendations
resulting from the relevant technical regulations. PCC materials, due to their advantages, are
widely used in repairs of hydrotechnical constructions, however, the correct application
conditions are the key. We have a proven set of polymer-cement materials combining
excellent physical and mechanical features with resistance to destructive environmental
activities. These materials tested in extreme conditions in which hydrotechnical marine
structures operate, is increasingly used in communication structures.
6. Literature
[1] Naprawa i ochrona konstrukcji z betonu. Komentarz do PN-EN 1504.Lech Czarnecki,
Paweł Łukowski, Andrzej Garbacz.
[2] Andrzej Królikowski Wykład Kurs IBDIM BETON I/2017
[3] PN-EN 1504 Wyroby i systemy do ochrony i napraw konstrukcji betonowych. Definicje,
wymagania, sterowanie jakością i ocena zgodności
[4] PN-EN 1504-3:2006 Wyroby i systemy do ochrony i napraw konstrukcji betonowych-
Definicje, wymagania, sterowanie jakością i ocena zgodności-Część 3:Naprawy
konstrukcyjne i niekonstrukcyjne.
[5]PN-EN 1504-2:2006 Wyroby i systemy do ochrony i napraw konstrukcji betonowych-
Definicje, wymagania, sterowanie jakością i ocena zgodności-Część 2:Systemy ochrony
powierzchniowej betonu
[6] Rozporządzenie Ministra Gospodarki Morskiej z 23.10.2006 r. w sprawie warunków
technicznych użytkowani a oraz szczegółowego zakresu kontroli morskich budowli
hydrotechnicznych. Dz.u.2006 pnr206,poz.516
[7] PN-EN 206+A1:2016-12.Beton-Wymagania,właściwości,produkcja i zgodność
[8] Lech Czarnecki Betony polimerowe. Cement.Wapno.Beton 2/2010
[9]Lech Czarnecki Betony polimerowe. Cement.Wapno.Beton 2/2010
[10] Lech Czarnecki, Paweł Łukowski.:Betony polimero-cementowe. Cement.Wapno.Beton
5/2010 [11 ] PN-EN 1504-9:2010 Wyroby i systemy do ochrony i napraw konstrukcji
betonowych-Definicje, wymagania, sterowanie jakością i ocena zgodności -Część 9:Ogólne
zasady dotyczące stosowania wyrobów i systemów.
[12] L. Czarnecki, Cement Wapno Beton, 2, 63-85, 2010
[13] Report on polymer-modified concrete, Report of ACI Committee 548, ACI Publication
nr 548.3R-09, Farmington Hills, USA, 2009
[14] J. Pera, J. Ambroise, 10th International Congress on Polymers in Concrete, Hawaii,
USA, 2001 (CD)
[15] Czarnecki L., Łukowski P.: Polymer-cement concretes. Cement Wapno Beton, 5, 2010,
243-258