polymer concrete report

Application of Polymer Concrete

APPLICATION OF POLYMER MODIFIED CONCRETE

1. INTRODUCTION

Despite being thought of as a modern material, concrete has been in use

for hundreds of years. The word concrete comes from the Latin concretus,

which means “mixed together” or compounded. Concrete is an extremely

popular structural material due to its low cost and easy fabrication.

Concrete is made up of sand or stone, known as aggregate, combined

with cement paste to bind it. Aggregate can be of various sizes. It is

broadly categorized as fine (commonly sand) and coarse (typically crushed

stone or gravel). The greater proportion of concrete is aggregate which is

bulky and relatively cheaper than the cement.

As much of the constituents of concrete come from stone, it is often

thought that concrete has the same qualities and will last forever.

Concrete has been called artificial stone, cast stone, reconstructed stone

and reconstituted stone. However, concrete must be thought of as a

distinct material to stone. It has its own characteristics in terms of

durability, weathering and repair.

Concrete is a relatively durable and robust building material, but it can be

severely weakened by poor manufacture or a very aggressive

environment. A number of historic concrete structures exhibit problems

that are related to their date of origin. These problems can be solved by

application of polymer in concrete construction.

A polymer is a large molecule containing hundreds or thousands of atoms

formed by combining one, two or occasionally more kinds of small

molecule (monomers) into chain or network structures. The main polymer

material used in concrete construction are polymer modified concrete and

polymer concrete.

Department of Civil Engineering, JNNCE Shivamogga


Polymer modified concrete may be divided into two classes: polymer

impregnated concrete and polymer cement concrete. The first is produced

by impregnation of pre-cast hardened

Portland cement concrete with a monomer that is subsequently converted

to solid polymer. To

produce the second, part of the cement binder of the concrete mix is

replaced by polymer (often in latex form). Both have higher strength,

lower water permeability, better resistance to chemicals, and greater

freeze-thaw stability than conventional concrete.

Polymer concrete (PC), or resin concrete, consists of a polymer binder

which may be a thermoplastic but more frequently is a thermosetting

polymer, and a mineral filler such as aggregate, gravel and crushed stone.

PC has higher strength, greater resistance to chemicals and corrosive

agents, lower water absorption and higher freeze-thaw stability than

conventional Portland cement concrete.

2. AIM

The main aims of this research are to identify and present the application

of polymer in concrete construction

3. OBJECTIVES

The objectives of this work are:

i) To study the application of polymer in concrete construction.

ii) To determine the advantage and disadvantage of polymer.

iii) To investigate the problems in the use of the polymer as repair

materials in concrete construction

4. INTRODUCTION TO POLYMERS



Polymers are a large class of materials consisting of many small molecules

(called monomers) that can be linked together to form long chains, thus

they are known as macromolecules. A typical polymer may include tens of

thousands of monomers. Because of their large size, polymers are

classified as macromolecules. Humans have taken advantage of the

versatility of polymers for centuries in the form of oils, tars, resins, and

gums.

However, it was not until the industrial revolution that the modern polymer

industry began to

develop. In the late 1830s, Charles Goodyear succeeded in producing a

useful form of natural

rubber through a process known as "vulcanization." Some 40 years later,

Celluloid (a hard plastic formed from nitrocellulose) was successfully

commercialized. Despite these advances, progress in polymer science was

slow until the 1930s, when materials such as vinyl, neoprene, polystyrene,

and nylon were developed. The introduction of these revolutionary

materials began an explosion in polymer research that is still going on

today Unmatched in the diversity of their properties, polymers such as

cotton, wool, rubber and all plastics are used in nearly every industry.

Natural and synthetic polymers can be produced with a wide range of

stiffness, strength, heat resistance, density, and even price. With

continued research into the science and applications of polymers, they are

playing an ever increasing role in society

5. POLYMER MODIFIED CONCRETE

Although its physical properties and relatively low cost make it the most

widely used construction material, conventional Portland cement concrete

has a number of limitations, such as low flexural strength, low failure

strain, susceptibility to frost damage and low resistance to chemicals.

These drawbacks are well recognized by the engineer and can usually be

allowed for in most applications. In certain situations, these problems can



be solved by using materials which contain an organic polymer or resin

(commercial polymer) instead of Portland cement. These relatively new

materials offer the advantages of higher strength, improved durability,

good resistance to corrosion and reduced water permeability.

There are three principal classes of composite materials containing

polymers:

1. Polymer impregnated concrete

2. Polymer cement concrete

3. Polymer concrete.

The distinction between these three classes is important to the design

engineer in the selection of the appropriate material for a given

application.

5.1 Polymer Impregnated Concrete

Polymer impregnated concrete is made by impregnation of pre-cast

hardened Portland cement concrete with low viscosity monomers (in either

liquid or gaseous form) that are converted to solid polymer under the

influence of physical agents (ultraviolet radiation or heat) or chemical

agents (catalysts). It is produced by drying conventional concrete;

displacing the air from the

open pores (by vacuum or monomer displacement and pressure);

saturating the open pore structure by diffusion of low viscosity monomers

or a pre-polymer-monomer mixture (viscosity 10 cps; 1 x 10-2 Pa·s); and in-

situ polymerization of the monomer or pre-polymer-monomer mixture,

using the most economical and convenient method (radiation, heat or

chemical initiation). The important feature of this material is that a large

proportion of the void volume is filled with polymer, which forms a

continuous reinforcing network. The concrete structure may be

impregnated to varying depths or in the surface layer only, depending on

whether increased strength and/or durability is sought. The main

disadvantages of polymer impregnated concrete products are their

relatively high cost, as the monomers used in impregnation are expensive



and the fabrication process is more complicated than for unmodified

concrete.

Impregnation of concrete results in a remarkable improvement in tensile,

compressive and impact strength, enhanced durability and reduced

permeability to water and aqueous salt solutions such as sulfates and

chlorides. The compressive strength can be increased from 35 MPa to 140

MPa, the water absorption can be reduced significantly. And the freeze-

thaw resistance is considerably enhanced. The greatest strength can be

achieved by impregnation of auto-claved concrete. This material can have

a compressive-strength-to-density ratio nearly three times that of steel.

Although its modulus of elasticity is only moderately greater than that of

non-autoclaved polymer impregnated concrete, the maximum strain at

break is significantly higher.

The monomers most widely used in the impregnation of concrete are, such

as

1. Methyl methacrylate (MMA)

2. Styrene

3. Acrylonitrile

4. T-butyl styrene

5. Vinyl acetate

Acrylic monomer systems such as methyl methacrylate or its mixtures

with acrylonitrile are the preferred impregnating materials, because they

have low viscosity, good wetting properties, high reactivity, relatively low

cost and result in products with superior properties. By using appropriate

bifunctional or polyfunctional monomers (cross-linking agents) in

conjunction with MMA, a cross-linked network is formed within the pores,

resulting in products with greatly increased mechanical strength and

higher thermal and chemical

resistance. Improvement of these properties will depend on the degree of

cross-linking. A cross-linking agent commonly used with vinyl monomers

such as MMA and styrene is trimethylolpropane trimethacrylate.



Thermosetting monomers and pre-polymers are also used to produce

polymer impregnated concrete with greatly increased thermal stability

(i.e. resistance to deterioration by heat). These include epoxy pre-

polymers and unsaturated polyester-styrene. These monomers and pre-

polymers are relatively viscous and, therefore, their use results in reduced

impregnation. Their viscosity can be reduced by mixing them with low-

viscosity monomers such as MMA.

Applications of concrete impregnated in depth in building and construction

include structural floors, high performance structures, food processing

buildings, sewer pipes, storage tanks for seawater, desalination plants and

distilled water plants. Marine structures, wall panels, tunnel liners,

prefabricated tunnel sections and swimming pools. Partially impregnated

concrete is used for the protection of bridges and concrete structures

against deterioration and repair of deteriorated building structures, such

as ceiling slabs, underground garage decks and bridge decks.

Table no: 5.1 General Characteristics and Applications of Polymer-

Modified Concretes

Polymer Impregnated Concrete

General

Characteristics

Consists generally of a pre-cast concrete, which has

been dried then impregnated with a low viscosity

monomer that polymerizes to form a network within

the pores. Impregnation results in markedly improved

strength and durability in comparison with conventional

concrete.

Principal

Applications

Principal applications include use in structural steel

floors, food processing buildings, sewer pipes, storage

tanks for seawater, desalination plants and distilled

water plants, wall panels, tunnel liners and swimming

pools.

Remark Disadvantage: Its relatively high cost, as polymer is



more expensive than cement and the production

process is more complicated.

5.2 Polymer Cement Concrete

Polymer cement concrete is a modified concrete in which part (10 to 15%

by weight) of the cement binder is replaced by a synthetic organic

polymer. It is produced by incorporating a monomer, pre-polymer-

monomer mixture, or a dispersed polymer (latex) into a cement-concrete

mix. To effect the polymerization of the monomer or pre-polymer-

monomer, a catalyst is added to the mixture. The process technology used

is very similar to that of conventional concrete. Therefore, polymer cement

concrete can be cast-in-place in field applications, whereas polymer

impregnated concrete has to be used as a pre-cast structure.

The monomers that are used are:

1. Polyster-styrene.

2. Epoxy-styrene.

3. Furans.

4. Vinylidene Chloride.

Modification of concrete with a polymer latex (colloidal dispersion of

polymer particles in water) results in greatly improved properties, at a

reasonable cost. Therefore, a great variety of latexes is now available for

use in polymer cement concrete products and mortars. The most common

latexes are based on poly (methyl methacrylate) also called acrylic latex,

poly (vinyl acetate), vinyl chloride copolymers, poly (vinylidene chloride),

(styrene-butadiene) copolymer, nitrile rubber and natural rubber. Each

polymer produces characteristic physical properties. The acrylic latex

provides a very good water-resistant bond between the modifying polymer

and the concrete components, whereas use of latexes of styrene-based

polymers results in a high compressive strength



Curing of latex polymer cement concrete is different from that of

conventional concrete, because the polymer forms a film on the surface of

the product. Retaining some of the internal moisture needed for

continuous cement hydration. Due to the film-forming feature, moist

curing of the latex product is generally shorter than for conventional

concrete.

Generally, polymer cement concrete made with polymer latex exhibits

excellent bonding to steel reinforcement and to old concrete. Its flexural

strength and toughness are usually higher than those of unmodified

concrete. The modulus of elasticity may or may not be higher than that of

unmodified concrete, depending on the polymer latex used. For example,

the more rubbery polymer. Generally, as the polymer forms a low

modulus phase with the polymer cement concrete, the creep is higher

than that of plain concrete and decreases with the type of polymer latex

used in the following order: polyacrylate; styrene-butadiene copolymer;

polyvinylidene chloride; unmodified cement

The drying shrinkage of polymer cement concrete is generally lower than

that of conventional concrete; the amount of shrinkage depends on the

water-to-cement ratio, cement content, polymer content and curing

conditions. It is more susceptible to higher temperatures than ordinary

cement concrete. For example, creep increases with temperature to a

greater extent than in ordinary cement concrete, whereas flexural

strength, flexural modulus and modulus of elasticity decrease.

The main application of polymer cement concrete is in floor surfacing, as it

is non-dusting and relatively cheap. Because of lower shrinkage, good

resistance to permeation by various liquids such as water and salt

solutions, and good bonding properties to old concrete, it is particularly

suitable for thin (25 mm) floor toppings, concrete bridge deck overlays,

anti-corrosive overlays, concrete repairs and patching



Recently Russian authors have reported the production of superior

Polymer Cement Concrete by the incorporation of furfurly alcohol and

aniline hydrochloride in wet mix. This material is claimed to be specially

dense and non shrinkage and to have high corrosion resistance, low

permeability and high resistance to vibration and axial extension.

Table no: 5.2 General Characteristics and Applications of

Polymer-Modified Concretes

Polymer cement concrete

General

Characteristics

Products made with thermosetting polymers and

polymer latex have greater mechanical strength,

markedly better resistance to penetration by water and

salt, and greater resistance to freeze-thaw damage than

Portland cement concrete; excellent bonding to steel

reinforcing and to old concrete

Principal

Applications

Major applications are in floors, bridge decks, road

surfacing and compounds for repair of concrete

structures. Latex modified mortar is used for laying

bricks, in prefabricated panels and in stone.

Remark

The mixing and handling are similar to Portland cement

concrete. However, in the production process, air

entrainment occurs without the use of an admixture,

and prolonged moist curing is not required

5.3 Polymer Concrete

Polymer concrete (PC) is a composite material in which the binder consists

entirely of a synthetic organic polymer. It is variously known as synthetic

resin concrete, plastic resin concrete or simply resin concrete. The main



technique in producing Polymer Concrete is to minimize void volume in the

aggregate so as to reduce the quantity of polymer needed for

binding the aggregate. This is achieved by properly grading and mixing

the aggregate to attain the maximum density and minimum void volume.

The graded aggregate are prepacked and vibrated in a mould. Monomer is

then diffused up through the aggregate and polymerization is initiated by

radiation or chemical means.

An important reason for the development of this material is the advantage

it offers over conventional concrete where the alkaline Portland cement on

curing, forms internal voids.

Water can be entrapped in these voids which on freezing can readily crack

the concrete. Also

the alkaline Portland cement is easily attacked by chemical aggressive

materials which result in rapid deterioration, whereas Polymer can be

compact with minimum voids and are hydrophobic and resistant to

chemical attack. The strength obtained by Polymer Concrete can be as

high as 140 MPa with a short curing period.

5.3.1 Nature and General Properties

Polymer concrete consists of a mineral filler (for example, an aggregate)

and a polymer binder (which may be a thermoplastic, but more frequently,

it is a thermosetting polymer). When sand is used as a filler, the composite

is referred to as a polymer mortar. Other fillers include crushed stone,

gravel, limestone, chalk, condensed silica fume (silica flour, silica dust)

granite, quartz, clay, expanded glass, and metallic fillers. Generally, any

dry, non-absorbent, solid material can be used as a filler.

Polymer concrete composites have generally good resistance to attack by

chemicals and other corrosive agents, have very low water sorption

properties, good resistance to abrasion and marked freeze-thaw stability.

Also, the greater strength of polymer concrete in comparison to that of

Portland cement concrete permits the use of up to 50 percent less



material. This puts polymer concrete on a competitive basis with cement

concrete in certain special applications. The chemical resistance and

physical properties are generally determined by the nature of the polymer

binder to a greater extent than by the type and the amount of filler. In

turn, the properties of the matrix polymer are highly dependent on time

and the temperature to which it is exposed

The viscoelastic properties of the polymer binder give rise to high creep

values. This is a factor in the restricted use of PC in structural applications.

Its deformation response is highly variable depending on formulation; the

elastic moduli may range from 20 to about 50 GPa, the tensile failure

strain being usually 1%. Shrinkage strains vary with the polymer used

(high for polyester and low for epoxy-based binder) and must be taken

into account in an application.

A wide variety of monomers and pre-polymers are used to produce PC.

The polymers most frequently used are based on four types of monomers

or pre-polymer systems: methyl methacrylate , polyester pre-polymer-

styrene, epoxide pre-polymer hardener and furfuryl alcohol. The typical

range of properties of PC products made with each of these four polymers

is presented in Table no: 5.3 General characteristics and principal

applications are described.

Table no: 5.3 General Characteristics and Principal Applications of

Polymer Concrete

Polymer Concrete



General

Characteristics

Polymer concrete or resin concrete made using

thermosetting polymer, and a mineral filler such as

aggregate, gravel and crushed stone. PC has higher

strength, greater resistance to chemicals and corrosive

agents, lower water absorption and higher freeze-thaw

stability than conventional Portland cement concrete.

Principal

Applications

Major applications are in floors, bridge decks, road

surfacing, storage tanks for seawater, swimming pools,

surfacing material and compounds for repair of

concrete structures. Polymer concrete mortar is used

for laying bricks, in prefabricated panels and in stone

Remark Uses of Polymer binder over comes the problem of

voids, micro cracks, permeability and cost effective etc.

Thus replaces the conventional concrete.

Table no: 5.4 Typical Range of Properties of Common PC Products

and Portland Cement Concrete

Type of

Binder

Densit

y

(kg/

dm)

Water

Sorptio

n (%)

Compressi

ve

Strength,

(MPa)

Tensile

Strengt

h

(MPa)

Flexura

l

Strengt

h (MPa)

Modulus

of

Elasticity

(GPa)

Poly(methylm

ethacrylate)2.0-2.4

0.05-

0.6070-210 9-11 30-35 35-40

Polyester2.0-2.4

0.30-

1.050-150 8-25 15-45 20-40

Epoxy2.0-2.4

0.02-

1.050-150 8-25 15-45 20-40

Furan

polymer 1.6-1.7 0.02 48-64 7-8 20-40 25-35

Portland 1.9-2.5 5-8 13-35 1.5-3.5 2-8 20-30



Cement

Concrete

6. PROPERTIES

6.1 Polymer Modified Concrete:

Stress-Strain Relationship

Polymer Impregnated Concrete has a nearly linear stress-strain relation to

failure there is a very little departure from linearity up to 90 percent of

ultimate strength and there is no abrupt change at the proportional limit.

The modulus of elasticity increased from 27 GPa for unimpregnated

specimen to 49 GPa for impregnated specimen.

Compressive strength

Using methylemethacrylate as monomer and with a polymer loading of 6.4

percent, strength of the order of 144 MPa has been obtained using

radiation technique of polymerization. The compressive strength obtained

with thermal catalytic process was 130 MPa.

Tensile Strength

The increase in tensile strength in the case of PIC has been observed to be

as high as 3.9 times that of the control specimen. Impregnated concrete

has shown tensile strength of order 11.6 MPa compare to the strength of

control specimen using rotation process of polymerization. The thermal

catalytically initiated polymerization produced concrete with tensile

strength 3.6 times that of the control specimen.

Polymer latex has given tensile strength of 5.8 MPa compared to the

controlled specimen of 4.4 MPa strength. Polyester resin concrete with

binder content varying from 20 to 25% have shown tensile strength in the

range of 9to 10 Mpa. At 7 days



Flexural Strength

Polymer impregnated concrete with MMA and polymerised by radiation

have shown flexural strength 3.6 times more than of the controlled

specimen, i.e. the flexural strength was increased to 18.8 MPa from 5.2

MPa.

Polyester resin concrete has been reported to give flexural strength of the

order of 15 MPa at 7 days.

Durability

Freeze Thaw Resistance: Polymer impregnated concrete has shown

excellent resistance to freeze-thaw MMA impregnated and radiation

polymerised specimen have withstood 8110 cycles of freeze-thaw

compared to 740 cycles in case of unimpregnated concrete.

Resistance to sulphate attack: There is 200 % improvement in the

resistance of polymer impregnated concrete and 89% improvement in

case of partially impregnated concrete over conventional concrete.

Acid Resistance: the acid resistance of PIC has been observed to

improve by 1200%.

Water absorption

A maximum reduction of 95% in water absorption has been observed.

Co-efficient of thermal expansion

Polymer impregnated concrete has shown appreciable improvement in

resistance to abrasion. Radiation polymerised concrete has a co-efficient

of thermal expansion of 4.02 X 10-6, radiation polymerised concrete has a

co-efficient of thermal expansion of 5.63 X 10-6 and styrene impregnated

specimens have value of 5.10 X 10-6.

Resistance to abrasion



Polymer impregnated concrete has shown appreciable improvement in

resistance to abrasion. MMA impregnated concrete has been found to be

50 to 80% more resistance to abrasion.

Wear and Skid Resistance

The treated surface show excellent skid resistance compared to the

unimpregnated surfaces. The wear after 50000 simulated vehicular passes

has been less than 0.025cm.

Fracture of Polymer Impregnated Concrete

Impregnation improves the strength of mortar matrix and the strength of

the paste-aggregate interface by elimination of microcracks. Polymer

probably enters the aggregates also forms a network of polymer fibers

across the interface, thus strengthening.

The typical properties of these polymer-containing concrete are compared

with those of conventional Portland cement concrete in Table. Their

general characteristics and applications are summarized as

Table no: 6.1 Typical Properties of Polymer-Containing Concrete

and Portland Cement Concrete

Material Tensile

Strength

(MPa)

Modulus

Of

Elasticity

(GPa)

Compress

ive

Strength

(MPa)

Shear

Bond

Strength

(KPa)

Water

Absorpti

on

(%)

Acid

Resistan

ce

Polymer

Impregnat

ed

Concrete

11.6 42 144

>4550

0.6 10

Polymer

Cement

Concrete

5.8 14 53 1 4

Polymer 10 40 140 0.5 8



concrete

Portland

Cement

Concrete

2.5 24.5 35 875 5.5 -

7. APPLICATION OF POLYMER MODIFIED CONCRETE

It is useful in a large number of application, some of which have been

listed and discussed below:

1. Prefabricated structural element.

2. Prestressed concrete.

3. Marine works.

4. Desalination plants.

5. Sewage Works- pipe and disposal works.

6. Ferrocement products.

7. For water proofing of structure.

8. Industrial applications.

9. Polymer Concrete Overlays.

10. Surfacing Material

11. Polymer Concrete Drainage System with Grating

12. Polymer concrete used to make Lintels

Prefabricated structural element

For solving the tremendous problem of urban housing storages,

maintaining quality, economy and speed, buildings had to fall back on

prefabricated technique of construction. At present due to low strength of

conventional concrete, the prefabricated sections are large and heavy,

resulting in costly handling and erection. These reasons have prevented

wide adoption of prefabricated in many countries.

At present, the technique of polymer impregnated is ideally suited for

precast concrete.



It will find unquestionable use in industrialization of building components.

Owing to higher strength, much thinner and lighter sections could be used

which enables easy handling and erection. They can be even used in high

raised buildings without much difficulty. Polymer concrete precast components

continue to be widely used for junction boxes, communication boxes, machine bases, railroad

crossings, and wall panels.

Figure 7.1 Rail crossings



Figure 7.2 Prefabricated Structure

Prestressed concrete

Further development in prestressed concrete is hindered by the inability

to produce high strength concrete, compatibility with high tensile steel

available for prestressing. Since PIC provides a high compressive strength

of the order of 100 to 140 MPa, it will be possible to use it for large spans

and for heavier loads. Low creep properties of PIC will also make it a good

material for prestressed concrete.

Marine Works

Aggressive nature of sea water, abrasive and leaching action of waves and

inherent porosity, impair the durability of conventional concrete in marine

works. PIC possessing high surface hardness, very low permeability and

greatly increased resistance to chemical attack, is a suitable material for

marine works.



Desalination Plants

Desalination of sea water is being resorted to augment the shortage of

surface and ground water in many countries. The material used in the

construction of distillation vessels in such works has to withstand the

corrosive effects of distilled water, brine and vapour at temperature upto

1430C. Preliminary economic evaluation has indicated a saving in

construction cost over that of conventional concrete by thus use of PIC.

Figure 7.3 Vessels



Figure 7.3 Vessels

Sewage Disposal Works

It is common experience that concrete sewer pipes deteriorate due to the

attack of effluents and when buried is sulphate infested soils. Further, in

the sewage treatment plant, concrete structures are subjected to severe

attack from corrosive gases particularly in sludge digestion tanks. Polymer

impregnated concrete due to its high sulphate and acid resistance will

prove to be a suitable material in these situations.



Figure 7.4 Egg Shaped Pipes

Figure 7.5 Circular Pipes

Ferrocement Products

The Ferrocement techniques of construction is being extensively used in manufacture of

boats, fishing trawlers, domestic water thanks, grain storage tanks, manhole cove, Chemical

Containment, Waste Containers etc.

Figure 7.6 Boat



Figure 7.7 Water Tank

Figure 7.8 Storage Tank



Figure 7.9 Man Hole and its Cover

Water proofing of structures

Seepage and leakage of water through roofs and bathrooms slabs, is a

nagging problem and has been fully over come by use of conventional

water proofing methods. The use of polymer impregnated mortar will solve

this problem.



Industrial Applications

Concrete has been used for floor for tanneries. Chemical factories, dairy

farms, base for a transformer and other machines. The newly developed PIC

will provide a permanent solution for durable flooring in such situations.

Machine Base Figure 7.10 Transformer Base

Polymer Concrete Overlays

Used to restore concrete surfaces such as driveways, sidewalks, patios, pool decks, etc. They

are used to level uneven concrete surfaces to correct water drainage problems, hide crack

repairs and discolored concrete. Once cracks are repaired, a thin layer of overlay is applied in

a decorative way to enhance the concrete surface. Overlays give old concrete a completely

new look.



Before After

Figure 7.11 Polymer Concrete Overlays

Surfacing Material

Polymer concrete is a proven surfacing material for both interior and exterior concrete

surfaces. The long lasting durability of polymer concrete is abrasion and impact resistant

coupled with being fully resistant to the thermal cycling of the harshest winter cold or the

blistering heat of the summer sun. The polymer concrete system will maintain its beauty and

durability for years to come. The cement coating can be applied as paint.



Before Figure 7.1 Surfacing Process After

Figure 7.13 Finished Floor by Polymer Concrete

Polymer Concrete Drainage System with Grating



Figure 7.14 Drainage System with Grating



Figure 7.15 Implementation of Drainage System

Polymer concrete used to make Lintels

Polymer Concrete Lintels are horizontal element intended to carry the load of the upper walls

of door and window spans.



Figure 7.16 Polymer Concrete Lintels

Figure shows the application of polymer in concrete construction. Polymer

used in selected the project sites can be classified as new structure,

existing structure and bridge. The typical application of polymer is used to

repair concrete defects on columns, beam and slab. From the figure, the

applications of polymer are more on beam for new structure. For the

existing structure and bridge, the applications of polymer are more on

slab.

Figure 7.17 The application of polymer in concrete construction



8. Application of Polymer Modified Concrete in Repair of

Column

A large copper mine and refinery in the western United States had a dilemma. Their cell

house, which contains over 1,500 cells, each holding more than 20,000 gallons of electrolyte,

had experienced severe corrosion and structural degradation of the support columns for the

tanks. Over time, highly acidic leakage from the cells had corroded the support columns to the

point that their ability to adequately withstand the imposed load was in doubt.

The leakage of copper sulfate and 25% sulfuric acid at a pH of 1.0 or less, corroded not only

the concrete but more significantly the No. 8 reinforcement bar (rebar) encased in the

concrete. Corrosion of the rebar resulted in an increase of internal pressure due to expansion

of the corrosion products, therefore putting the concrete in high tensile stress. The direct

effect of this stress was cracking the concrete. Figure 8.1 shows a typical degradated column

requiring restoration.

Figure 8.1 Column Degradation

The original construction of the columns used No. 8 rebar spaced 6-inches on center vertically

and 18-inches on center horizontally. The refinery’s standard repair procedure was to remove

corrosion products from the concrete and steel and then to top them with a polymer-modified

portland-cement mortar. They decided upon a new approach using a polymer concrete (PC).

This material is designed for maximum flowability, mechanical properties and chemical

resistance. The PC repair system utilizes the polymer concrete for encapsulation, chemical

protection, mechanical support and resistance to physical abuse.



Figures 8.2 illustrate the method by which the stainless steel rebar was attached to

the columns after surface-preparation. Stainless steel rebar was imbedded into the concrete

floor using an epoxy mortar. These channels provided a recess into which the rebar was bent

and then secured into place with the epoxy mortar. Grouting of the rebar with this high

strength epoxy mortar also served to provide tensile stress relief. By lowering stress relief,

corrosion rates are reduced.

Figure 8.2 Stainless steel rebar bent and grouted

Polymer concrete was poured into place completely encapsulating the columns and

the rebar. 75 columns have been repaired using this method. Figures 8.3 and 8.4 show the

forming and pouring of the PC. Figure 8.5 shows the PC after the form has been removed.

Figure 8.3 The forms placed around the column



Figure 8.4 Pouring of the polymer concrete

Figure 8.5 Columns after removal of forms

A slump of 6 inches is considered to be flowable. This particular polymer concrete used

exhibits a slump of 8-inches, which is very flowable. Figures 7.6 illustrate the flowability of

the polymer concrete mixture.

Figure 8.6 Slump Test



The PC is roughly three times as strong as a portland cement mix and is not chemically

affected by the electrolyte. These properties make it an ideal product for the

column restoration. As expected, none of the 75 columns repaired to date have exhibited any

signs of failure and have required no maintenance since the repair program commenced in

early 2007. Coatings will typically have a service life of 8 to 15 years depending upon the

exposure and physical abuse. Figure 8.6 illustrates the completed column.

Figure 8.6 Completed column repair



9. CONCLUSION

Corrosion protection from a severely aggressive electrolyte, as well as protection from

physical abuse.

Polymer concretes are also proving to be cost effective alternatives to using portland

cement-based concretes with chemical-resistant topcoats for corrosion protection.

The cost of maintenance for polymer concretes per year of service life is significantly

less than that of concrete with applied barrier coatings, which may require multiple

re-applications over the same number of years of service.

Polymer Concrete can be used for realizing the rehabilitation of structures by coating

or for realizing structural elements such as beams, columns, foundation beams, etc.

The substitution of cast iron with polymer concrete in machine tool main spindle

housing has been made. Without considerable reduction in static performances a

significant improvement in damping is obtained.

The new product, development time and the manufacturing cost have been

dramatically reduced due to the simplification of the production process.

The mechanical and chemical resistant properties of PIC composites are superior to

the conventional cement mortar

Porosity of the conventional cement mortar is greatly reduced when it is impregnated

with polymers thereby increasing its durability when it is exposed to chemically

polluted environments

Polymers give a more compact structure to the cement matrix and seal the cracks in

cement mortar matrix.

The main use of these materials is in thin section applications, in waterproofing and

protection of concrete structures.

10. Reference



Application of Polymer in Concrete Construction by LEEENG HING in the year

2007/2008.

Concrete Technology Theory and Practice Text book by M.S. SHETTY.

Design and manufacture of hybrid polymer concrete bed for high-speed CNC milling

machine by JUNG DO SUH and DAI GIL LEE.

Polymer Concrete White Paper by David E. Snider and Heather M. Ramsey.

The compressive strength of a new urea formaldehyde-based polymer concrete by

A. ALZAYDI AND S. A. SHIHATA.


polymer concrete report

Documents