Important: Use custom search function to get better results from our thousands of pages

Use " " for compulsory search eg:"electronics seminar" , use -" " for filter something eg: "electronics seminar" -"/tag/" (used for exclude results from tag pages)


 
 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Special concretes Report
Post: #1

Special concretes


.docx  Special concretes.docx (Size: 543.74 KB / Downloads: 66)

INTRODUCTION:

Special types of concrete are those with out-of-the-ordinary properties or those produced by unusual techniques. Concrete is by the definition a composite material consisting Essentially of a binding medium and by aggregate particles, and it can take many forms. Lists many special types concrete made with Portland cement and some made with binders other than Portland cement. In many cases the terminology of the listing describes the use, property, or condition of the concrete. Some Special Types of Concrete Special types of concrete made with Portland cement Architectural concrete light concrete Heavy weight concrete Recycled concrete Autoclaved cellular concrete High-early-strength concrete ,, Roller- compacted concrete Centrifugally low cast concrete and High -performance concrete Sawdust concrete aggregates. The term “sand lightweight” refers to light weight concrete made with coarse lightweight aggregate and natural sand. Structural lightweight concrete has an air-dry density in the range of 1350 to 1850 kg/m3 (85 to 115 pcf) and a28- day compressive strength in excess of 17 MPa (2500psi). Some job specifications allow air-dry densities up to 1920 kg/m3 (120 pcf).

AUTOCLAVED CELLULAR CONCRETE

Autoclaved cellular concrete (also called autoclaved aerated concrete)is a special type of lightweight building material. It is manufactured From mortar consisting of pulverized siliceous material (sand, slag, or fly ash) , cement and/or lime, and water; to this a gas forming admixture, for example aluminum powder, is added. The chemical reaction of aluminum with the alkaline water forms hydrogen, which expands the mortar as macrospores with a diameter of 0.5 mm to 1.5 mm (0.02 in. to 0.06 in.) form. The material is then pressure steam cured (autoclaved) over a period of 6 to 12 hours using a temperature of 190ºC (374ºF) and a pressure of 1.2 MPa (174 psi). This forms hardened mortar matrixes. This porous mineral building material has densities between 300 and 1000 kg/m3 (19and 63 lb/ft 3) and compressive strengths between 2.5 and 10 MPa (300 and 1500 lb/in2). Due to the high macrospore content— up to 80 percent by volume—autoclaved cellular concrete has a thermal conductivity of only 0.15 to 0.20 W/(m•K) (1 to 1.4 Btu•in./ [h•ft2•ºF]). Autoclaved cellular concrete is produced in block or panel form for construction of residential or commercial buildings .

MASS CONCRETE

Mass concrete is defined by ACI Committee
116 as “Any large volume of cast-in-place
concrete with dimensions large enough to
Require that measures be taken to cope with
The generation of heat and attendant volume
Change to minimize cracking.” Mass
Concrete includes not only low- cement-
Content concrete used in dams and other
Massive structures but also moderate- to
High-cement-content concrete in structural
Members of bridges and buildings.

POLYMER-PORTLAND CEMENT CONCRETE

Polymer-Portland cement concrete (PPCC),
also called polymer-modified concrete, is
basically normal Portland cement concrete
to which a polymer or monomer has been
added during mixing to improve durability
and adhesion. Other Thermoplastic and
elastomeric latexes are the most commonly
used polymers in PPCC, but epoxies and
other polymers are also used. In general,
latex improves ductility, durability, adhesive
properties, resistance to chloride-ion ingress
, shear bond , and tensile and flexural
Strength of concrete and mortar. Latex-
Modified concretes (LMC) also have
excellent freeze- thaw, abrasion, and impact
resistance. Some LMC materials can also
resist certain acids, alkalis, and organic
Solvents. Polymer-Portland cement concrete
is primarily used in concrete patching and
Overlays, especially bridge decks. See ACI
548.3R for more information on polymer-
Modified concrete and ACI 548.4 for LMC overlays.

Colored Concrete

Colored concrete can be produced by using
Colored aggregates or by adding color
Pigments (ASTM C 979) or both. When
Colored aggregates are used, they should be
exposed at the surface of the concrete. This
can be done several ways; for example,
Casting against a form that has been treated
With a retarder. Un hydrated paste at the
Surface is later brushed or washed away.
Other methods involve removing the surface
Mortar by sandblasting, water blasting,
Bush hammering, grinding, or acid washing.
If surfaces are to be washed with acid, a
delay of approximately two weeks after
casting is necessary. Colored aggregates
may be natural rock such as quartz, marble,
and granite, or they may be ceramic
materials. Pigments for coloring concrete
should be pure mineral oxides ground finer
than cement; they should be insoluble in
water, free of soluble salts and acids,
colorfast in sunlight, resistant to alkalies
and weak acids, and virtually free of
calcium sulfate.

CONCLUSION

In this paper we have discussed about the
Special concretes which are very effective
And economical to . On using these type of
concretes the construction will also be
Durable for many years. In the above
concretes there are also developing concrete
will help in reducing the cost of builing and
increase the life span of construction
Post: #2
The special types of concrete are those with properties out of the ordinary or produced by unusual techniques. Concrete is, by definition, a composite material consisting essentially of a bonding medium and aggregate particles, and can take many forms. Special concrete is concrete for special purpose for increased strength and durability for various construction applications. Special concretes are concrete prepared for specific purpose such as light weight, high density, fire protection, radiation shielding etc. concrete is a versatile material that has good compressive strength. But it suffers from many drawbacks such as low tensile strength, liquid permeability, reinforcement corrosion, susceptibility to etching and low durability. Modifications have been made from time to time to overcome the deficiencies of cement concrete. Recent developments in materials and construction technology have led to significant changes that have resulted in improved performance, wider and more economical use.
 

Marked Categories : water hammering in pipe, seminar report on special type of concrete, pdf special concrete seminar topic, special concretes for seminors, concrete cost,

[-]
Quick Reply
Message
Type your reply to this message here.

Image Verification
Image Verification
(case insensitive)
Please enter the text within the image on the left in to the text box below. This process is used to prevent automated posts.

Possibly Related Threads...
Thread: Author Replies: Views: Last Post
  seminar report on zettabyte file system Guest 0 0 06-12-2018 09:30 AM
Last Post: Guest
  GREEN COMPUTING A SEMINAR REPORT email2ktr 17 50,418,055 04-12-2018 08:51 AM
Last Post: bpatrickmshtozey2048
  11 commerce o c m project report of seasonal goods Guest 0 0 19-11-2018 12:39 PM
Last Post: Guest
  a report on procedure of winding up partnership firm project pdf Guest 3 0 14-11-2018 12:45 AM
Last Post: Prathamesh Sanap
  project report on solenoid engine Guest 0 0 05-11-2018 07:09 PM
Last Post: Guest
  hydraulic vise project report Guest 0 0 20-10-2018 02:31 AM
Last Post: Guest
  data mining full report project report tiger 35 285,873,591 13-10-2018 05:10 PM
Last Post: banattivanovy4591
  double piston single connecting rod mini project report Guest 5 1,794 29-09-2018 10:00 AM
Last Post: Guest
  android financial notifier project documentation report Guest 6 890 26-09-2018 03:43 PM
Last Post: Guest
Video 3 wheel handicapped steering propulsion cycle project report pdf Guest 0 0 18-09-2018 10:42 AM
Last Post: Guest
This Page May Contain What is Special concretes Report And Latest Information/News About Special concretes Report,If Not ...Use Search to get more info about Special concretes Report Or Ask Here

Options: