21-11-2012, 12:21 PM
PAPER PRESENTATION ON POLYMER CONCRETE
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ABSTRACT:
In Concrete Technolgy there are many types of Concretes here we are mainly discussing
about Polymer Concrerte. Polymer concrete is a composite material. A graded mixture
coarse and fine aggregates bound together by an appropriate organic resin system. Polymer
concrete is a relatively low-cost composite material system that has been developed to be a
technically viable alternative to porcelain for most high voltage electrical insulation
applications. Polymer composites appear as useful materials for repair and protection of
building structures, as well as for manufacturing pre-cast elements. In the case of pre-cast
elements as well as repair materials, the usefulness and durability of polymer composites
depend on the selection of the material composition for obtaining the composite with
controllable properties Polymer 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.
INTRODUCTION
Polymer concrete 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.
Because the use of a polymer instead of Portland cement represents a substantial increase in
cost, polymers should be used only in applications in which the higher cost can be justified
by superior properties, low labor cost or low energy requirements during processing and
handling. It is therefore important that architects and engineers have some knowledge of the
capabilities and limitations of PC materials in order to select the most appropriate and
economic product for a specific application.
NATURE AND GENERAL PROPERTIES:
Polymer concrete consists of a mineral filler and a polymer binder (which may be a
thermoplastic, but more frequently, it is a thermosetting polymer. When it 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, granite, quartz, clay, expanded glass, and metallic
fillers.
To produce PC, a monomer, a hardener and a catalyst are mixed with the filler. Other
ingredients added to the mix include plasticizers and fire retardants. To achieve the full
potential of polymer concrete products for certain applications, various fiber reinforcements
are used. These include
glass fiber,
glass fiber-based mats,
fabrics and
metal fibers.
The amount polymer binder used is generally small and is usually determined by the size of
the filler. Normal the polymer content will range from 5 to 15 percent of the total weight, but
if the filler is fine, up t 30 percent may be required.
MATERIALS AND TESTING PROGRAM
Based on workability, polymer content for GFRPC and CFRPC were determined to be 18%
and 20% respectively. Fiber content for both the matrices was varied up to 6%. CIGMAT
standards (CIGMAT PC1-01, CIGMAT PC2-01, CIGMAT PC3-01) were followed for
specimen preparations, compression test and tension test. Destructive tests were performed in
displacement-controlled mode.
Furan Polymer Concrete :
Furan polymers are based on furfuryl alcohol, which is derived from agricultural residues
such a corn cobs, rice hulls, oat hulls or sugar cane bagasse. The furan pre-polymer is usually
cross-linked with furfuryl alcohol, furfuraldehyde to yield thermosetting polymers, high
resistant to most aqueous acidic or basic solutions and strong solvents such as ketones,
aromatics, and chlorinated compounds. The furan polymers are used as binders in mortars
and grouts to achieve chemically resistant brick floors and linings. In addition to exhibiting
superior chemical resistance, these floors have excellent resistance to elevated temperatures
and extreme thermal shock.
Polymerization :
Polymer- modified cementitious materials date back more than 70 years. In the 194G's they
were developed for use on ships' decks and bridges. Polymers arc made from simple organic
molecules that combine to form more complex structures through a process called
polymerization. The polymers are dispersed in water. These are added to hydraulic cement,
with or without aggregate or admixtures, depending on trip desired result.