type of concrete
TRANSCRIPT
School of Architecture, Building and Design Bachelor
of Quantity Surveying (HONOURS)
Assignment: Research on building material- Concrete
Name: Student Id:
Tan Kai Sin 0315213
Tan Chuu Yee 0315097
Tan Wen Hao 0313690
Section: March intake 2014
Lecturer: Pn. Mokhtar Hasmanira
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Introduction
Concretes are now commonly used in our buildings. However, there are several type of
concretes produced by mixing difference ingredients and using difference type of
technologies. Each type of concrete carries out its own function and applications.
Therefore, in order to understand more about the building materials, a research report is
prepared. The concretes that be focused in this report are prestressed concrete, precast
concrete, reinforced concrete, ready mix concrete, terrazzo and urbanite concrete.
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Table of content
Cover Page------------------------------------------------------------------------------------------------- 1
Introduction------------------------------------------------------------------------------------------------- 2
Content------------------------------------------------------------------------------------------------------ 3
Prestressed Concrete----------------------------------------------------------------------------------- 4-
7
Precast Concrete--------------------------------------------------------------------------------------- 8-11
Reinforced Concrete--------------------------------------------------------------------------------- 12-
13
Ready-mix Concrete--------------------------------------------------------------------------------- 14-18
Terrazzo------------------------------------------------------------------------------------------------- 19-
23
Urbanite Concrete------------------------------------------------------------------------------------ 24-25
Reference Link---------------------------------------------------------------------------------------- 26-27
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Prestressed Concrete
Prestressed concrete double tee roof slabImages obtained from http://www.archiexpo.com/prod/alfanar/prestressed-concrete-double-tee-roof-slabs-
89130-915174.html [Accessed 25 Apr. 2014]
Definition
Prestressed concrete is basically concrete in which initial and permanent stresses of
such magnitude and distribution are deliberately introduced that the stresses due to
dead weight and externally applied loads are counteracted to a desired degree.
Prestressing is achieved by tensioning the tendon then transferring its tensile stress to
concrete as compressive stress called as Prestress. (Structure-structural-
software.blogspot.com, 2014)
General Information
Prestressed Concrete is a technique that greatly increases load bearing strength of
concrete beams. The reinforcing steel in the bottom part of the beam, which will be
subjected to tensile forces when in service, is placed in tension prior to the concrete
being poured around it. Once the concrete has hardened, the tension of the reinforcing
steel is released, placing a built-in compressive force on the concrete. When loads are
applied, the reinforcing steel takes on more stress and the compressive force in the
concrete is reduced, but does not become a tension force. Since the concrete is always
under compression, it is less subject to cracking and failure.
It is a method for overcoming concrete’s natural weakness in tension. Prestressed
concrete can be used to produce beams, floors, bridges with a longer span than is
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practical with ordinary reinforced concrete. Prestressing tendons are used to provide a
clamping load which produces a compressive stress the balance the tensile stress that
the concrete compression member would otherwise experience a bending load.
(Cement.org, 2014)
Prestress concrete beamImages obtained from http://www.archiexpo.com/prod/prestasi-concrete-sdn-bhd/prestressed-concrete-t-
beams-56829-126833.html [Accessed 25 Apr. 2014]
Applications
Prestress can be applied to all concrete structures subjected to direct tension, bending
or impact stresses. Prestress is applied to bridge girders, long span beams, tanks, forge
hammer foundations. It is applied to bomb shelters and pressure vessel in atomic
reactors. It is advantageously used in Railway sleepers, Electric poles and in pressure
pipes. Also, it could be applied to any material such as steel, timber, etc.
(Psakthikumaran.hpage.in, 2014)
Advantages/Disadvantages
For the advantages, it includes crack control and lower construction costs for the
project. Moreover, it is strong in for using in situations where tension is used.
For the disadvantages, the availability of builders experienced with work of prestressing
is very less. Besides, Initial equipment cost for prestressing is very high. The cost of
high strength of materials is high. Moreover, the availability of Engineers experienced
with prestressing work is very less. Furthermore, Prestressed sections are brittle
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because high tensile steel is used. All High strength steels have higher carbon content.
Slender sections are difficult to transport. Lastly, prestressed concrete sections are less
fire resistant.
Sustainability
Prestressed concrete uses much less materials than reinforced concrete, so that the
savings can reach 40% of the overall mass. Its longer spans, thinner and lighter
elements allow a reduction in number of piles, height of buildings, consumption of
energy in freight and handling, therefore CO2 emissions.
Illustrations of prestressed concrete beam
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Image obtained from http://fabricalo.net/index.php/comment-fabriquer-du-beton-
precontraint/ [Accessed 25 Apr. 2014].
Image obtained from http://theconstructor.org/structural-engg/pcd/classification-of-prestressed-concrete/15/ [Accessed 25 Apr. 2014].
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Precast Concrete
Image obtained from http://atlasalshemal.com/?portfolio=praesent-commodo-cursus [Accessed 25 Apr. 2014].
Definition
It is a construction material made from casting concrete into reusable form which is later
cured in a controlled environment, then transported to the construction site and lifted
into place. Precast concrete is made from precast stone as it is mixed with fine
aggregate.
General Information
Precast concrete systems combine structural and architectural components to create
long-lasting buildings and structures. Precast concrete product is a factory-made piece
manufactured with concrete and which, later, together with other pieces, will become
part of a larger structure. Precast concrete elements are prepared, cast and hardened
at specially equipped plants with a permanent location. Once a precast concrete is
produced and all the undertaken quality controls satisfactory, the unit is stored until
delivery. It is then transported for use at another site. (Cement.org, 2014)
Properties
Precast concrete products are manufactured from a mix of raw materials, including sand
and gravel aggregates, pulverized fuel ash (PFA), Cement, Limestone dust, Crushed
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rock and Inert pigments. Precast concrete product in a range of colors, sizes and
finishes.
Advantages/Disadvantages
For the advantages, precast concrete slabs are usually the correct size as it is
manufactured off site. Moreover, precast concrete saves a lot of time on site as it is
manufactured off site. It also saves a lot of space on site as pre-cast concrete is usually
on site when required. In addition, precast concrete saves money in terms of labor on
site as pre-cast concrete can usually be assembled by semi-skilled operatives.
(Answers.com, 2014)
For the disadvantages, precast concrete is lacks design and dimension flexibility as the
manufactures may only have fixed shapes and sizes. Precast concrete may also affect
the construction program as the delivery on site may not always be on time. Besides,
precast concrete may incur addition financial costs as delivery on site may not always
be on time. Lastly, precast concrete allows for a very small margin for error as the
incorrect dimensions of pre-cast concrete may result in changing the entire design.
Sustainability
Precast concrete offers high durability and strength as well as thermal mass, which
contributes to increased energy efficiency. Precast systems use locally derived
materials, and can incorporate recycled supplementary cementations materials like fly
ash and slag cement, one of the key reasons why they are often used in sustainable or
“green” buildings. (Continuingeducation.construction.com, 2014)
Aesthetical Value
A number of aesthetic benefits are possible with the use of precast concrete facades.
Among the visual considerations outlined is the use of integral color throughout the
precast slabs. In many typical applications, the use of pigmentation is isolated to an
exterior portion and sandwiched against the uncolored grey cement, which typically
comprises the interior. Integral color affords some advantages in design expression.
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Maintenance
1. After a building or structure is erected, it should be cleaned as required.
2. Precast expands and contracts. Ensure the precast joints are properly sealed.
3.The precast structure should be power-washed every four to six years to maintain its
original appearance.
4. If pigment is used in the manufacture of the precast units, a non-acid cleaning
treatment is recommended. (www.intrigue.co.nz, 2014)
Precast Concrete Type AImage obtained from http://www.constructionweekonline.com/article-17403-precast-takes-the-lead/
#.U10G9_mnons [Accessed 25 Apr. 2014].
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Precast Concrete Type BImage obtained from http://latuxdbd.com/blog/2013/12/why-choose-precast-concrete/ [Accessed 25 Apr.
2014].
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Precast Concrete Type CImage obtained from http://formworkblog.com/public/1652 [Accessed 25 Apr. 2014].
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Reinforced Concrete
Definition:
Reinforced concrete is concrete that mixed with very strong materials that increase the
strength under tension of the concrete, making it less likely to fail (McMahon, M.2014).
Nowadays, reinforced concrete is one of the most common and famous building
materials in the world for both of the entire building and the key structural elements that
need to be able to bear up extensive stress. In addition, reinforced concrete is mix with
two materials act together in resisting forces. There were reinforcing-rods, bars, or
mesh-absorbs the tensile, shear.
Application on reinforced concrete
Reinforced concrete can be classified as precast or cast in place concrete. Its uses as
designing and implementing the most efficient floor system is to creating optimal
building structures. As research, without the reinforced concrete that the construction
modern structures with concrete material would not be possible sustain.
Type of reinforced concrete
According to concrete technology, there are different types of reinforced concrete which
are Glass fibre reinforced concrete (GFRC), Steel fibre reinforced concrete (SFRC) and
Ferro concrete.
Ferro concrete
As the specific type of reinforced concrete, it’s known as Ferro concrete. Based on the
Ferro concrete, these concrete is with metal bars, plates or grids. The other materials
involved as plastics, fibre and glasses. It does can also make the building stronger.
Glass fibre reinforced concrete (GFRC)
These concrete was successfully used since the last 25 years for concrete
reinforcement. In addition, Glass Fibre Reinforced Concrete, also known as GFRC or
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GRC, is a type of fibre reinforced concrete. Glass fibre concretes are mainly used in
exterior building frontage panels and as architectural precast concrete. Slightly similar
materials are fibre cement siding and cement boards.
Steel fibre reinforced concrete (SFRC)
Steel fibre reinforced concrete is superior resistance to cracking and crack propagation
(Nguyen Van.C). Nowadays, industrial floor and pavements are major applications for
steel-fibre-reinforced concrete.
Physical characteristic of reinforced concrete
The physical characteristics that impact reinforced concrete are concrete that control
the definition of gases, such as CO2, O2 or liquid (mainly water) through it pores and
the diffusion of ions, such as CL-, dissolved in the pore water (Vagelis.G, 1991).
Advantages of reinforced concrete
It is a structural material and widely used in many types of structures. It is inexpensive
with steel if economically deliberate and executed. There are some advantages which
are it has a relatively high compressive strength, better conflict to fire then steel, long
service life with lower maintain cost, can be cast to take the shape required.
Disadvantages of reinforced concrete
There were also summarized the disadvantages of reinforced concrete which are low
tensile strength of about one-tenth of its compressive strength, cost of the forms used to
cast of concrete placed in forms. In addition, the reinforced concrete needs also mixing,
casting and remedial and the cracks develop in concrete due to decline and the
application of live loads.
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Ready-mix concrete
Definition:
Ready-mix concrete is concrete that is manufactured in a factory or batching plant,
according to a set recipe, and then delivered to a work site, by truck mounted in-transit
mixers. In addition, ready-mix concrete are low cost, robustness and its ability to be
customize for different application, ready-mix concrete is one of the most adaptable and
popular building materials.
Application of ready-mix concrete
Ready-mix concrete is produced under factory conditions and certifications a close
control of all operations of manufacture and conveyance of fresh concrete. This
technique is useful in congested site or diverse work Places and saves the consumer
from botheration of attaining, storage and handling of concrete materials.
Type and special function of different type of ready-mix concrete
There are a few examples of ready-mix concrete technologies with special properties
and performance.
1. Architectural and Decorative Concrete
- It does provide a structural function, as well as an aesthetic or decorative
finish. It can offer smooth, rough surfaces or textures. As well as a variety or
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range of colours.
2. Rapid-setting concrete
- Design to enhance early strength development, this concrete allows fast
formwork removal, accelerated construction sequencing and rapid repair for
jobs as roads and airport runways. Those concrete normally used in low
temperature (5-10/C) concreting during winter.
-
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3. Fibre-reinforced concrete
- Its design with micro or macro fibres can be used either for structural
applications, where the fibre can theoretically substitute for steel rebar
reinforced or for reducing shrinkage.
4. Fluid-fill concrete
- Fluid mortar or concrete shortens the process of laying pipe and cable by
surrounding the pipe or cable with a tightly packed shell that provides
protection from the elements, avoids settling, and enables crews to work
quickly.
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5. Roller-compacted concrete
- Compressed in place and cured, roller-compacted concrete is a zero slump
concrete with the abrasion resistance to withstand high velocity water and
making it the material of choice for spillways and other infrastructure subject
to high flow conditions. It represents an inexpensive solution in terms of cost
and durability when compared to asphalt.
6. Previous concrete
- It’s has the unique design mix, previous concrete is a highly porous material
that allows water, rainwater to filter through and reduces flooding and heat
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concentration by up to 4C and its also help to prevent skidding on wet roads.
7. Antibacterial concrete
- This concrete controls bacteria growth and is used to help maintain clean
environments in structures such as hospitals, laboratories, and farms.
Disadvantages of ready-mix concrete
The materials are batched at a central plant, and the mixing begins at that plant, so the
traveling time from the plant to the site is critical over longer distances. Some sites are
just too far away, though this is usually a commercial rather than a technical issue.
Advantages of ready-mix concrete
The material has the benefit of speedy construction through continuous mechanized
operation leading to economy. The lower labor and supervisory cost assured. Then, the
multi-transportation of raw materials for concrete is eliminated and it’s also controlled
W/C ratio and the close quality control of batching reduces variability of the desired
properties of hardened concrete.
Photo of ready-mix concrete
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Terrazzo
The word of " Terrazzo" is derived from the Italian “Terrace” or “Terrazza” and by
definition over the centuries: “A form of mosaic flooring made by embedding small
pieces of marble in mortar and polishing.” Today, the National Terrazzo and Mosaic
Association (NTMA) defines this traditional material as follows: “Terrazzo consists of
marble, granite, onyx or glass chips in portland cement, modified portland cement or
resinous matrix. The terrazzo is poured, cured, ground and polished. Terrazzo can be
poured in place or precast.” (The National Terrazzo & Mosaic Association, Inc. , 1999)
Application of Terrazzo
Terrazzo can be used in indoor and outdoor design. Terrazzo is used for floors,
counters, stairs, bases, tabletops and so on.
Type of Terrazzo
According to NTMA there are 6 type of terrazzo which are epoxy terrazzo, sand cushion
terrazzo, bonded terrazzo, monolithic terrazzo, polyacrylate terrazzo and rustic terrazzo.
Epoxy terrazzo
Epoxy terrazzo is the best thin set system and among other thin set system, it is the
most strongest and durable. It is not recommended for exterior use because it is not
breathable, thus, it cannot stand with the harsh weather outside.
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Example of Epoxy terrazzo.Images obtained from http://ntma.com/epoxy-terrazzo/ [Accessed 20 Apr. 2014]Sand Cushion Terrazzo
Sand Cushion Terrazzo is a cement matrix topping underbed with wire reinforcing,
isolation sheet, and sand layer system for interior floor use. (The National Terrazzo &
Mosaic Association, Inc. , n.d) It can prevent the mirroring effect on the surface of
flooring. Therefore, it is ideally used for incorporating design patterns and multiple
colors surface area.
Example of Sand Cushion TerrazzoImage obtained from http://ntma.com/sand-cushion-terrazzo/ [Accessed 20 Apr. 2014]
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Bonded Terrazzo
Bonded Terrazzo can be used for interior and external applications. It can become slip-
resistance by acid-washed. Moreover, it is breathable, so it does not effected by vapor
transmission. However, compare to sand cushion terrazzo, it does not has that many
color and it takes longer time to cured than other types of Terrazzo. (Cabella Stone
Corp., 2014)
Example of Bonded TerrazzoImage obtain from http://ntma.com/bonded-terrazzo/[Accessed 20 Apr. 2014]Monolithic Terrazzo
Monolithic Terrazzo is a type of terrazzo that "directly applied on a concrete surface
instead of a mortar bed" (WebFinance, Inc., 2014) Monolithic terrazzo is the most
economical of all terrazzo systems and it is high quality and durable especially if used in
applications like large retail stores, shopping malls and schools. (Cabella Stone Corp.,
2014)
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Example of Monolithic TerrazzoImage obtained from http://www.cjamescollection.com/Floorazzo.htm [Accessed 20 Apr. 2014]
Polyacrylate Terrazzo
For polyacrylate, an acrylic additive is incorporated into the mixture of modified cement
which is to allow the cement to be poured as thickly or as thinly, up to one and a half
inch thick. Polyacrylate Terrazzo can be used in outdoor because it is breathable.
(Cabella Stone Corp., 2014)
Example of Polyacrylate TerrazzoImage obtained from http://www.concretedecor.net/decorativeconcretearticles/vol-7-no-4-junejuly-2007/new-polyacrylate-terrazzo/[Accessed 20 Apr. 2014]
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Rustic Terrazzo
Rustic terrazzo mostly used in outdoor applications. It has a rough surface due to slip-
resistance purpose. The aggregate that used for Rustic Terrazzo are quartz, granite,
quartzite,and silica pebbles.
Example of Rustic TerrazzoImages obtained from http://ntma.com/venetian-rustic-terrazzo/[Accessed 20 Apr. 2014]
Advantage of Terrazzo
Various color, durable, Nonporous finish does not support bacterial growth, mold, or
mildew, low maintenance, Abrasion resistance, and eco-friendly.
Disadvantage of Terrazzo
Sensitive to harsh cleaners, all-purpose cleaners and soaps containing water-solubles.
Avoid sweeping compounds containing oil as it may permanently discolor the materials.
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Urbanite Concrete
Urbanite concrete is "a term that refers to broken pieces of unwanted concrete leftover
from a demolition project. " (Tate, 2014)
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Urbanite ConcreteImage obtained from http://apdiggs.wordpress.com/category/urbanite-2/ [Accessed 20 Apr. 2014]
Application of Urbanite Concrete
According to Kathleen Story, 2013, urbanite concrete can be used as foundation and
base of a building. Besides, it also can used to be building walls, patios, walkways,
planters, benches, fire pits, flower beds, stepping stones and so on.
Wall that built from Urbanite ConcreteImage obtained from http://setinstone-landscaping.com/portfolio/broken-concrete-urbanite/ [Accessed 20 Apr. 2014]
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Pathways built from Urbanite concreteImages obtained from http://setinstone-landscaping.com/portfolio/broken-concrete-urbanite/ [Accessed 20
Apr. 2014]
Properties of Urbanite Concrete
As urbanite is known as recycled concrete, therefore, it carries out the same properties
as concrete. According to Cement Sustainability Initiative, 2012, concrete is strong,
durable, fire-resistance, reduce temperature swing and apply albedo effect.
Advantage of Urbanite Concrete
Urbanite concrete carry a lot of advantages. For instance, it is non-biodegradable. Next,
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it can be cut in virous sizes and shapes. Besides, it is cost- saving and eco-friendly
because it is recycled. (Story, 2013)
Disadvantage of Urbanite Concrete
The disadvantages of urbanite concrete are hard to haul because it can be very heavy.
Moreover, it does not has virous designs. (Story, 2013)
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Reference link
Merriam-webster.com,. (2014). Reinforced concrete - Definition and More from the Free Merriam-Webster Dictionary. Retrieved 2014, April 25, from http://www.merriam-webster.com/dictionary/reinforced%20concrete
Slideshare.net,. (2014). Structure Reinforced Concrete. Retrieved 2014, April 25, from http://www.slideshare.net/MatNik1/structure-reinforced-concrete
wiseGEEK,. (2014). What Is Reinforced Concrete? (with picture). Retrieved 2014, April 25, from http://www.wisegeek.com/what-is-reinforced-concrete.htm
The National Terrazzo & Mosaic Association, Inc. (1999). Types and System. Retrieved 2014, April 20, from http://ntma.com/pharaohs-dance/terrazzo-types-systems/
Cabella Stone Corp., (2014). Terrazzo Flooring. Retrieved 2014, April 20 from http://www.terrazzotoday.com/what-is-terrazzo/terrazzo-flooring/
WebFinance, Inc., (2014). Monolithic Terrazzo. Retrieved 2014, April 20 from http://www.dictionaryofconstruction.com/definition/monolithic-terrazzo.html
Tate, Sarah (2014). Urbanite: Repurposing Old Concrete. Retrieved 2014, April 20 from http://www.concretenetwork.com/concrete/demolition/urbanite-recycled-concrete.html
Story, Kathleen (2013). Green Build with Urbanite, Broken Concrete, Retrieved 2014, April 20, from http://www.examiner.com/article/green-build-with-urbanite-broken-concrete
World Business Council for Sustainable Development (n.d). Properties of Concrete. Retrieved 2014, April 20 from http://www.wbcsdcement.org/index.php/key-issues/sustainability-with-concrete/properties-of-concrete
Answers.com, (2014). What are advantages and disadvantages of precast Concrete?. [online] Retrieved 2014, April 25, from http://wiki.answers.com/Q/What_are_advantages_and_disadvantages_of_precast_Concrete
Cement.org, (2014). Precast/Prestressed Concrete. Retrieved 2014, April 25, from http://www.cement.org/think-harder-concrete-/buildings-structures/design-aids/precast-prestressed-concrete
Continuingeducation.construction.com, (2014). Style and Sustainability of Precast Concrete | Sponsored by Holcim (US) Inc. | Originally published in the November 2012 issue of Architectural Record | Architectural Record's Continuing Education Center. [online] Retrieved 2014, April 25, from http://continuingeducation.construction.com/article.php?L=323&C=949
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Psakthikumaran.hpage.in, (2014). WELCOME TO CIVILIZION. [online] Retrieved 2014, April 25, from http://psakthikumaran.hpage.in/pre-stressed-concrete_37967137.html
Structure-structural-software.blogspot.com, (2014). Definition of Prestressed Concrete. [online] Retrieved 2014, April 25, from http://structure-structural-software.blogspot.com/2011/02/definition-of-prestressed-concrete.html
www.intrigue.co.nz, l. (2014). Maintenance of Precast Concrete. [online] Wilcoprecast.co.nz. Retrieved 2014, April 25, from http://www.wilcoprecast.co.nz/maintenance/html
Lootahgroup.com,. (2014). What is Ready Mix Concrete Defination Defining. Retrieved 2014, April 25, from http://www.lootahgroup.com/html/nrc_pro_what.php
Answers.com,. (2014). What are advantages and disadvantages of ready mix concrete?. Retrieved 2014, April 25, from http://wiki.answers.com/Q/What_are_advantages_and_disadvantages_of_ready_mix_concrete?#slide=6
Cemexusa.com,. (2014). Architectural/Decorative Concrete | Types of Concrete | Concrete | Products & Services | CEMEX USA. Retrieved 2014, April 25,, from http://www.cemexusa.com/ProductsServices/ArchitecturalDecorativeConcrete.aspx
Heidelbergcement.com,. (2014). Ready-mix Concrete - hanson - HeidelbergCement in Malaysia. Retrieved 2014, April 25,, from http://www.heidelbergcement.com/my/en/hanson/products/rmx_concrete/index.htm
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