decorative concrete

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Seminar Report on Decorative concrete 2015-2016 INTRODUCTION Decorative concrete is the use of concrete as not simply a utilitarian medium for construction but as an aesthetic enhancement to a structure, while still serving its function as an integral part of the building itself such as floors, walls, driveways and patios. The transformation of concrete into decorative concrete is achieved through the use of a variety of materials that may be applied during the pouring process or after the concrete is cured, these materials and/or systems include but are not limited to stamped concrete, acid staining, decorative overlays, polished concrete, concrete countertops, vertical overlays and more. Dept. of Civil Engg. 1 GPTC Muttom

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Decorative Concrete

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Page 1: Decorative Concrete

Seminar Report on Decorative concrete 2015-2016

INTRODUCTION

Decorative concrete is the use of concrete as not simply a utilitarian medium for

construction but as an aesthetic enhancement to a structure, while still serving its

function as an integral part of the building itself such as floors, walls, driveways

and patios.

The transformation of concrete into decorative concrete is achieved through the use

of a variety of materials that may be applied during the pouring process or after the

concrete is cured, these materials and/or systems include but are not limited to

stamped concrete, acid staining, decorative overlays, polished concrete, concrete

countertops, vertical overlays and more.

Dept. of Civil Engg. 1 GPTC Muttom

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Seminar Report on Decorative concrete 2015-2016

Stamped Concrete

Stamped Concrete is the process of adding texture and color to concrete to make it

resemble stone, brick, slate, cobblestone and many other products found in nature

including wood, fossils, shells and many more. This limitless array of possibilities

combined with great durability and lower cost than natural products makes

Stamped Concrete an easy choice for new construction and renovation projects.

The installation consists of pressing molds into the concrete while the concrete is

still in its plastic state. Color is achieved by using Dry Shakes or Color Hardeners,

Powder or Liquid Releases, Integral Colors or Acid Stains. All these products may

be combined to create even more intricate designs.

Stamped Concrete may be used on driveways, patios, commercial roads and

parking lots and even interior floors. Stamped concrete is a desirable finish to

concrete areas, however with time and wear the color dyes fade and the surface

looks patchy and unpresentable. There are many re-coloring options which can

completely restore and rejuvenate the color and presentation of faded stamped

concrete.

Dept. of Civil Engg. 2 GPTC Muttom

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Concrete dyes

Concrete "dyes" take many different forms and compositions and can be used on

both residential and commercial concrete applications, including sound/retaining

walls, bridges, countertops, floors,[1] etc.

Early concrete dyes consisted of generic printing inks that were dissolved in mild

solutions of alcohol and applied to concrete surfaces to add a wide array of color to

plain gray concrete. When alcohol-based dyes are exposed to sunlight, the color

either lightens or fades out completely. Therefore, alcohol-based dyes were more

prevalent in interior applications where direct sunlight or other forms of ultraviolet

(UV) lighting was not present.

Manufacturers later began dissolving the same printing inks in different carriers,

such as acetone, lacquer thinner and other solvents, hoping to achieve increased

penetration levels. In addition, UV inhibiting agents were added to new dyes to

help with the UV instability issues. However, slight fading (5-8% per year) still

occurs when the dye is exposed to direct sunlight.

Colored concrete can be obtained from many ready mix concrete companies and

many have color charts available.

Dept. of Civil Engg. 3 GPTC Muttom

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Acid Staining

Acid staining is not a dyeing or pigment-base coloring systems, but a chemical

reaction. A mixture of water, mineral salts and a slight amount of muriatic acid is

applied to the concrete surface. This chemical reaction with the existing minerals

(primarily lime) in the concrete over a period of one to four hours creates new

earth tone colors on the concrete surface. The concrete surface is later scrubbed to

remove excess stain and neutralized by a basic solution of ammonia and water or

baking soda (less likely to cause whiting later) to help raise the ph level back to

normal level. Due to inconsistencies in the surface level of concrete floor, acid

staining creates a variegated or mottled appearance that is unique to each slab. The

color penetration ranges from 1/16 to 1/32 of an inch. Older exterior concrete

surfaces may not color as well as interior surfaces because the environment has

leached or percolated out the mineral content. As well, any exposed aggregate

(rocks) in worn concrete will not accept staining.

Chemicals commonly used in acid staining include Hydrochloric acid, Iron

chloride and Sodium bicarbonate.

Dept. of Civil Engg. 4 GPTC Muttom

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Water Based Staining

Water Based Stains are similar to acid based stains in the sense that one can still

achieve a translucent look like acid; some stains are able to achieve an opaque

color and/or a translucent effect. The main difference is that acid stains react to the

concrete and change the physical make up of the concrete material, whereas water

based stains are more of a "coating" that bonds with the concrete. There are many

variations of water based stains that have come into the decorative concrete

industry that perform in a number of different ways. Some are polymer based,

acrylic and epoxy.

Overlaying

Concrete overlays date to the 1960s when chemical engineers from some of the

larger, well known chemical companies began to experiment with acrylic paint

resins as modifiers for cement and sand mixes. The result was a thin cementitious

topping material that would adhere to concrete surfaces and provide a newly

resurfaced coating to restore the worn surface. Concrete overlays lacked the long-

term performance [2] characteristics of acrylic resins. Acrylic resins provided good

Dept. of Civil Engg. 5 GPTC Muttom

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UV resistance, but lacked long term water resistance and adhesion characteristics

needed to provide a long term and permanent solution.

Polymer cement overlays

Construction of a polymer cement overlay to change asphalt pavement to brick

texture and color to create decorative crosswalk and traffic calming in high-

pedestrian area.

Polymer cement overlays, consisting of a proprietary blend of Portland cements,

various aggregates and polymer resins, were introduced over 20 years ago. The

purpose of adding a polymer resin to the cement and aggregate is to greatly

increase the performance characteristics and versatility of conventional cements,

mortars and concrete materials. Unlike conventional cement and concrete mixes,

polymer cement overlays can be applied thinly or thickly without fear of

delamination or typical product failure. In addition, polymer cement overlays are

much more resistant to damage from salt, petrochemicals, UV, harsh weather

conditions and traffic wearing.

Dept. of Civil Engg. 6 GPTC Muttom

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Originally intended for use as a thin surface restoration material for concrete

substrates, polymer cement overlays were introduced into the architectural

concrete and commercial flooring industries in the early 80s. Subsequently, its use

in these industries has become standard. Polymer cement overlays are regarded as

economical in providing long term, durable renovation without the need for costly

and continuous repairs associated with deteriorating concrete surfaces.

Polymer cement overlays are used for interior and exterior applications ranging

from:

Skim coat/broom finish concrete resurfacing – Restore and protect damaged,

pitted, flaking and stained concrete back to the look of a new concrete

surface.

Concrete regrading & leveling – Repair and level concrete surfaces that have

settled.

Existing substrate redecorating and renovating – Alter the appearance of

existing concrete or wood substrates through applying "thin stamped" or

"thin stained" overlays, creating new textures, colors and designs. For use on

commercial or resident pool deck, this frequently takes the form of "splatter

textures" or "knockdowns," in which polymer cement is applied to the

existing concrete substrate in a moderately textured finish (average of 1/8”

Dept. of Civil Engg. 7 GPTC Muttom

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thickness) in various patterns. Often, the texture is knocked down with a

trowel to slightly modify the appearance and feel of the finished application.

Stamped overlays

Rubber imprinting tools (stamps) are impressed into thin pre-mixed concrete

overlay material shortly after it is placed to create natural stone or brick textures.

These rubber imprinting tools are manufactured from molds created from authentic

stone or wood. Release agents are used to help release the stamps from the

concrete without sticking. Release agents come in either a liquid or powder form

and are available in a wide range of colors.

Epoxy coating

Applied over acid stained, dyes and/or overlays to seal and protect. Some epoxies

are also colored.

Polishing

Concrete can be polished with Mechanical grinders and diamond pads of

increasing grit sizes. Diamond pads come in many grit or mesh sizes. Common

sizes start with 6 grit and can go up to 8500 grit although concrete can only

maintain a shine of about 800 grit, it can be helped by adding a concrete hardener

such as sodium silicate or lithium silicate which will allow concrete to hold a 1800

Dept. of Civil Engg. 8 GPTC Muttom

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through 3000 grit shine. The work is accomplished in multiple stages by passing

over the concrete with successive grit diamond pads until it has a hard-glassy

finish. Both acid stains and concrete dyes can be used during the polishing process.

Engraving

Existing concrete can be remodeled by cutting lines and grooves into its surface.

Geometric patterns, straight or curved lines and custom designs can be cut directly

into the surface of the concrete creating the look of tile, flagstone, cobblestone and

many other common surface patterns. This is usually achieved using tools like an

angle grinder fitted with diamond blades, but is more effectively accomplished

using specialty tools designed specifically for cutting designs into the concrete.

Form liner

Concrete can also be cast into unique and detailed designs using urethane form

liner. These projects can be seen around the United States and the world, usually

on sound/retaining walls, building exteriors, and bridges.

Generally, this process starts with the sculptor, who creates the design to be used in

the concrete using clay, polyurethane or wax. When the original art is complete, a

cast is made using synthetic liquid rubber, and from this cast, form liners are

produced in the reverse image of the original.

Dept. of Civil Engg. 9 GPTC Muttom

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The form liner then acts as a mold for the concrete to be formed against. Once the

concrete is set, the form liner is stripped from the hardened concrete surface. The

concrete is permanently textured with the pattern of the form liner.

Architectural & Decorative Concrete

Concrete is one of the most widely used construction materials in the world. One

special subset is called architectural and decorative concrete, which refers to a

substance that provides an aesthetic finish and structural capabilities in one. This

material is made to be seen. Whether creating broad expanses or minute details,

concrete permanently captures the chosen look. Achieving an architectural or

decorative appearance usually requires that something different be done to the

concrete. Whether that involves special forms, special finishing techniques, or

special ingredients, the variety of effects is almost unlimited. 

Original art by Carolyn Braaksma, Denver, Colorado

Concrete is one of the most widely used construction materials in the world. One

special subset is called architectural and decorative concrete, which refers to a

Dept. of Civil Engg. 10 GPTC Muttom

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substance that provides an aesthetic finish and structural capabilities in one. This

material is made to be seen. Whether creating broad expanses or minute details,

concrete permanently captures the chosen look. Achieving an architectural or

decorative appearance usually requires that something different be done to the

concrete. Whether that involves special forms, special finishing techniques, or

special ingredients, the variety of effects is almost unlimited. 

White Portland Cement: A Key Ingredient

White cement concrete is a brilliant architectural

material. Whether plain or pigmented, it allows for a broad spectrum of colors -

from bright whites and pastels to saturated colors. It can be textured, patterned, or

shaped to almost any form, allowing architects to be truly creative in their designs.

Imagination becomes architectural reality with white cement.

What makes white cement so architecturally appealing is its versatility. It can be

used for:

o Cast-in-place concrete

Dept. of Civil Engg. 11 GPTC Muttom

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o Precast concrete

o Tilt-up concrete

o Repair and retrofit applications

o Masonry and mortar

o Stucco finishes

Good Looks and More

From large to small items, structural to decorative members, white cement is the

key to good looking concrete and masonry construction. A versatile appearance

allows white cement concrete, which is pigment-friendly, to fit in with any

environment. Beyond aesthetics, its light color offers energy efficiency and safety.

These qualities can be used to advantage for:

o Bridge parapets and barrier medians                               

o Light reflective floors

o Exposed architectural concrete

o City streetscapes: curbs, gutters and planters

Dept. of Civil Engg. 12 GPTC Muttom

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o Landscaping

o Building accents

Whether inside or outside, white cement concrete provides a hard-wearing, durable

surface that stands up to heavy use.

Technical Aspects of Designing with White Cement Concrete

White portland cement has essentially the same properties as gray cement, except

for its color. An important quality control issue in the industry, the color of white

cement depends on raw materials and the manufacturing process. Metal oxides,

primarily iron and manganese, influence the whiteness and undertone of the

material. White cement is manufactured to conform to ASTM C 150, Specification

for Portland Cement. Types I and III are the most common, but Types II and V are

also produced.

Mix designs for white or colored concrete are

formulated with respect to the following ingredients, paying particular attention to

the resultant effect on color:

Dept. of Civil Engg. 13 GPTC Muttom

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o Type and color of cement

o Type and dosage of pigment

o Type and dosage of chemical admixtures

o Type, gradation, color, and cleanliness of fine and coarse aggregates

o Type and dosage of supplementary cementing materials: calcined clay, slag,

white silica fume

o Consistent proportions, especially maintaining a uniform water-cement ratio

It is always recommended to develop a mix design and build sample panels in

advance of starting a white cement concrete project. That way, mixtures can be

refined and improved and material usage can be optimized. The mockups serve as

references for color and surface appearance during the construction phase of the

project.

Materials & Applications

Architectural and Decorative Concrete

Dept. of Civil Engg. 14 GPTC Muttom

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Concrete is one of the most widely used construction materials in the world. One

special subset is called architectural and decorative concrete, which refers to

cement-based products that provide an aesthetic finish and structural capabilities in

one.

These concrete materials are made to be seen. Whether creating broad expanses or

minute details, concrete permanently captures the chosen look. Achieving an

architectural or decorative appearance usually requires that something different be

done to the concrete. Whether that involves special forms, special finishing

techniques, or special ingredients, the variety of effects is almost unlimited.

For more information see PCA's Finishing Concrete with Color and Texture,

PA124.

Dept. of Civil Engg. 15 GPTC Muttom

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Masonry

Masonry is one of our oldest, most established

building techniques. Evolution in materials, mix designs, and engineering allow for

the construction today of even stronger masonry buildings—structures that will last

for generations. 

Concrete masonry units are available in a rainbow of colors, textures, shapes, and

sizes, offering building designers the chance to create structural walls that are also

beautiful. Architectural concrete masonry units offer a natural appearance that is

striking in urban applications, and blends in with the natural beauty of rural areas

—always complementing the building’s surrounding environment. 

Stucco

Dept. of Civil Engg. 16 GPTC Muttom

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Stucco, or portland cement plaster, is a versatile facing

material that can be applied to flat or curved surfaces either inside or outside any

building or structure. Stucco has great appeal as a surface finish because of its

utility, low first cost, and minimum need for maintenance.

In its hardened state, plaster is a desirable facing material: hard, strong, fire-

resistant, and color-retentive. Because plaster is also breathable, or able to transmit

moisture vapor, water that gets behind it does not become trapped. That makes it

resistant to rot and fungus. Plaster has proved to be a durable wall cover in all

climates, whether wet, dry, hot, or cold. 

The final appearance of the finish coat can be varied by changing the size and

shape of the aggregate, using colored cement, adding pigments, changing the

consistency of the finish mix, the method or equipment used for plastering, and the

plasterer's skill in manipulating the finish coat.

Pervious Concrete

Dept. of Civil Engg. 17 GPTC Muttom

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Pervious concrete, is one of the hottest topics

in land development today. As owners, architects, land developers, and concrete

professionals become familiar with its benefits, the interest in pervious concrete

continues to grow.  Pervious concrete is porous and provides a solution to the EPA

regulations that call for decreasing the amount of surface water runoff and initially

treating the runoff.

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Break New Ground with a Time-Tested Material

Masonry combines beautiful design possibilities

with versatility and value, durability and low maintenance, in any size, style, or

climate. 

From civic and cultural facilities to institutional settings, buildings designed with

masonry stand the test of time.  Masonry also is an investment in living well for

home owners.  With its ability to withstand extreme temperatures, fires, and natural

disasters, masonry keeps adding value to residential properties.

Masonry is also the sensible choice for educational buildings. For school design

that innovates and is proven to perform, again and again its masonry.

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Masonry Products and Properties

Masonry units are available in sizes, shapes, colors, textures, and profiles for

practically every conceivable need. Historically, units came from a variety of

sources and included materials such as rock and stone, either natural or cut. Today,

units most commonly used are concrete block or clay brick, offering standardized

sizes and mechanical properties. The units are joined together by mortars made

from a binder consisting of one or more cements for masonry, sand, and water.

Portland cement plaster, or stucco, is made from the same material as mortars, and

as such, is sometimes considered to be a masonry product as well.

Masonry is widely used to construct small and large structures because of its

attractive appearance, minimum maintenance, safety (fire resistance and

wind/earthquake resistance), and economy. Masonry provides an effective barrier

to sound and reduces internal temperature variations and peak loads on heating and

cooling systems. It provides architectural freedom and versatility with striking

aesthetic appeal. Almost any shape of structure is possible.

When high winds occur, reinforced masonry buildings resist the pressures and

flying debris that can knock down or damage less robust construction. Masonry

can offer fire resistant qualities that saves homes.

Dept. of Civil Engg. 20 GPTC Muttom

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Masonry also resists weathering and vandalism. The durability and minimum

maintenance extend a building’s useful life, providing an enduring, high-quality

appearance.

Masonry Products

Modern masonry products include portland cement plaster (stucco), cements for

masonry, mortars, concrete block, and clay brick. These materials can be used on

the interior or exterior of structures in a wide range of environments. Load-bearing

walls serve a structural purpose, while veneers and claddings, frequently used as

architectural finishes, also function as weather barriers. Whichever materials are

used, modern masonry construction provides durability, safety, aesthetic appeal,

and other benefits in a cost-effective manner. 

Brick

Brick is the oldest manufactured building material. The earliest brick, made from

mud (sometimes with added straw), was invented almost 10,000 years ago. Clay

brick started to appear about 5,000 years ago, when builders borrowed pottery

manufacturing techniques to improve its strength and durability. From some of the

oldest known structures to modern buildings, clay brick has a history of providing

shelter that is durable, comfortable, safe, and attractive.

Dept. of Civil Engg. 21 GPTC Muttom

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Cements for Masonry

Cements for masonry include masonry cement (ASTM C 91) and mortar cement

(ASTM C 1329). They are hydraulic cements designed for use in mortar for

masonry construction. Masonry cement consists of a mixture of portland cement or

blended hydraulic cement and plasticizing materials (such as limestone or hydrated

or hydraulic lime), together with other materials introduced to enhance one or more

properties such as setting time, workability, water retention and durability. These

components are proportioned at the cement plant under controlled conditions to

assure uniformity of performance. 

Concrete Masonry Units

Since 1882, when the first concrete block was molded, concrete masonry units

have become a standard building material. Concrete blocks create structures that

are economical, energy efficient, fire-resistant, and involve minimal maintenance.

In addition, concrete masonry allows architectural freedom and versatility.

Mortar & Grout

Masonry mortar is composed of one or more cementitious materials, clean well-

graded masonry sand, and sufficient water to produce a plastic, workable mixture.

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Grout for masonry is composed of similar materials, but is generally mixed to a

much more fluid condition. It may also contain coarse aggregate.

Stucco

Stucco, the common term for portland cement plaster, is a popular exterior finish

for buildings. It provides an economical hard surface that is rot, rust, and fire

resistant, which can be colored and finished in a wide range of textures to adorn

any architectural style.

Masonry is one of our oldest, most established building techniques. Evolutions in

materials, mix designs, and engineering allow for the construction today of even

stronger masonry buildings—structures that will last for generations.

Aesthetic Variety

Concrete masonry units are available in a rainbow of colors, textures, shapes, and

sizes, offering building designers the chance to create structural walls that are also

beautiful. Architectural concrete masonry units offer a natural appearance that is

striking in urban applications, and blends in with the natural beauty of rural areas

—always complementing the building’s surrounding environment.

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Safety and Durability

When it comes to fire resistance, masonry is a true performer, offering excellent

protection from fire damage. In fact, post-9/11 research performed on a building in

close proximity to the World Trade Center showed that masonry absorbed much of

the debris impact and helped save the structure from collapsing. In fact, the

building was repaired and restored to use. Masonry structures are also stand up to

high wind forces and earthquakes. More on Safety and Durability.

Sustainability

As with other concrete wall systems, masonry creates walls with high thermal

mass, minimizing temperature swings and shifting heating and cooling loads to

off-peak hours. The resulting buildings are more economical, with lower overall

heating and cooling costs, providing a consistently comfortable atmosphere for

inhabitants. Masonry also offers durability as well as sound attenuation—which

all adds up to a more quiet, comfortable atmosphere for inhabitants.

Applications

Masonry lends itself to many commercial applications. The material has been

used to create notable public buildings like churches, courthouses, and

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government offices. Educational structures, from elementary schools to Ivy

League university facilities, can balance contemporary engineering with

traditional design, offering myriad possibilities that will stand the test of time.

Technician Training

Two new masonry certification programs – one for Masonry Laboratory Testing

Technicians and the other for Masonry Field Testing Technicians – are available.

Developed by The American Concrete Institute (ACI), in cooperation with The

Masonry Society (TMS) and other industry organizations, both certification

programs aim to improve the quality of masonry testing and recognize qualified

technicians.

Both exams include a written portion and a performance portion. Technicians who

successfully complete either exam will receive a 5-year certification from ACI for

field or lab testing. It is suggested that individuals prepare for the exams through

TMS review sessions that combine classroom instruction, lab demonstrations, and

lab practice time. To learn more about the new certifications, see information at

The Masonry Society or the American Concrete Institute.

.

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Industry Resources

Detailed information on designing with masonry and masonry mortars is available

on PCA's Masonry site. There is excellent information on the safety of masonry

regarding fire resistance, high wind force resistance, and earthquakes.

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CONCLUSION

Decorative concrete is the use of concrete as not simply a utilitarian medium for

construction but as an aesthetic enhancement to a structure, while still serving its

function as an integral part of the building itself such as floors, walls, driveways

and patios.The transformation of concrete into decorative concrete is achieved

through the use of a variety of materials that may be applied during the pouring

process or after the concrete is cured, these materials and/or systems include but

are not limited to stamped concrete, acid staining, decorative overlays, polished

concrete, concrete countertops, vertical overlays and more.

Dept. of Civil Engg. 27 GPTC Muttom

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REFERENCES

Fox, Joanne (May 16, 2009). "Concrete Staining Adds Color to Flooring".

Sioux City Journal.

Downs, Stacy (April 10, 2008). "Paving the way for concrete despite freeze-

thaw cycles, driveway should last for years if properly installed".

Chicagotribune.com.

Dept. of Civil Engg. 28 GPTC Muttom