Classification and Types of concrete
In the world of civil engineering, learned about the classification and the types of concrete as an introduction to enable us to understand and recognize how where or what the concrete to facilitate the conduct of research as one who studied civil engineering. Immediately following a review of the calcification and other types of concrete.
- Calcification concrete
In general, the concrete can be classified into two main parts: the fresh concrete and hard concrete. The following illustrate the fresh concrete and hard concrete.
- Fresh concrete is concrete that is shrinking after drying process.
Important matters relating to the properties of fresh concrete,
namely:
1. Ease of processing (workability) of this nature is a measure of the level of convenience for stirring mortar, transported, poured and compacted. The elements that affect the ease of processing of fresh concrete properties:
a. The amount of water used in the concrete mix. The more water used the more easily done fresh concrete.
b. The addition of cement into the mix because it would be followed by increased water mixture to obtain fas fixed value.
c. Gradation mixture of sand and gravel.
d. The use of maximum pebble grain used.
e. The use of rock grains are rounded
f. How to determine the concrete compaction properties of different workmanship.
2. Separation of gravel. The tendency of a grain of gravel to separate from the concrete mixture called segregation. Gravel separation tendency is magnified by:
a. The mixture is thin (less cement).
b. too much water.
c. The larger grains of gravel.
d. The more rough gravel surface.
Separation of gravel concrete mix resulted in less well against the concrete after hardening.
To reduce the tendency of the separation of the gravel then sought the following matters:
Continued:
1. Given water as little as possible
2. The concrete should not be inflicted with a height too great.
3. How hauling, pouring and compacting should follow the right ways.
- Concrete hard
The mechanical properties of hard concrete are classified as follows:
- The nature of the short-term or instantaneous, which consists of:
- Compressive strength
Compressive strength of concrete is influenced by:
1. Comparison of water-cement and compacting level.
2. Cement type and quality (affects average power and strong concrete boundary).
3.Type and contours of the surface areas of aggregates.
4. Age (in normal circumstances the power increase with age)
5. Temperature (speed up concrete hardening increases with increasing temperature).
6. Efficiency and treatment
- Pull Strength
Concrete tensile strength ranging from 1/18 strength of concrete at a young age and range from 1/20 afterwards.
Usually not taken into account in the planning of concrete buildings.
Tensile strength is an important part in retaining the cracks due to moisture and temperature changes.
- Shear strength
In practice, the shear in the concrete is always followed by a press and pull by bending and even in the test may not eliminate bending elements.
B. The nature of the long-term, which consists of:
1. Creep
Creep is the additional volume of the concrete works due time.
Factors influencing creep are:
a. strength (creep reduced if the greater increase in strength),
b. mixture ratio (when fas and reduced the volume of cement pastes creep decreases),
c. cement,
d. aggregate (creep increases when more fine aggregate),
treatment,
e. age (creep speed is reduced in line with the age of concrete).
2. Decrease
Shrinkage is the reduction in the volume of concrete elements in the event of loss of moisture due to evaporation.
Factors that affect the amount of shrinkage is:
a. aggregate (as anchoring cement paste shrinkage),
b. water-cement ratio (fas greater the greater the shrinkage effect),
c. size concrete elements (lag and the magnitude of shrinkage will be reduced if the volume of the larger concrete elements)
d. environmental conditions,
e. amount of reinforcement,
f. additive
The Classification of concrete by volume is as follows:
1. Ordinary concrete (concrete Ordinary): 1.80 g/cm3.
2. Lightweight concrete (light weight concrete): 0.6 to 1.8 g/cm3.
3. Insulating concrete heat (Heat insulation concrete):
0.6 g/cm3
Based on usage distinguished by:
1. Ordinary concrete or also called reinforced concrete (concrete Reiforced) for constructions carry the load.
2. Concrete building water normally used or found in the manufacture of sluice, canal etc.
3. Special Concrete Concrete normally as acid, heat resistant
Types of concrete
Next we will discuss about the types of concrete. There are six types of concrete are often used or found in the main building of various in Indonesia. The concrete types are as follows:
- Ferrosemen is a composite material obtained by providing a reinforcement in the form of woven steel wire as the giver of tensile strength and ductility in cement mortar.
- Concrete Fiber (Fibre Concrete) is a composite material consisting of a plain concrete and other materials in the form of fibers. Fibers in the concrete prevents cracks that makes the concrete more ductile than ordinary concrete. Commonly known type is the GRC (Glass-fiber Reinforced Concrete).
- Non Concrete Sand (No-Fines Concrete) is the simpler of the type b entuk lightweight concrete is obtained by eliminating part in the making of fine aggregate concrete. The absence of fine aggregate in the mixture menghasilkansuatu cavity system is distributed in the form of uniformity in the concrete mass, and reduced density of concrete
- Concrete is concrete Cyclops normal / ordinary concrete, which uses a relatively large aggregate size. Coarse aggregate size up to 20 cm, but a greater proportion of the aggregate should be no more than 20 percent of the aggregate total.
- Empty concrete is concrete that once stirred and poured and compacted concrete as usual, the rest of the reaction water is sucked in a special way, disebutcara vacuum (vacuum method). Water left behind only water used for reaction with cement concrete thus obtained is very strong.
- Mortar Concrete is composed of sand mortar, adhesive, and water. Mortar can be divided into three kinds, namely: mud mortar, lime mortar, and cement mortar.
The main function of the concrete and reinforcement
Concrete is a composite material that has a very great function for humans. Concrete is composed of three main types of constituent materials, namely cement, aggregate, and water are mixed with the correct amount. In addition to these three types of materials also contained material which is usually the fourth is also frequently used in the manufacture of a concrete admixture. In the structure of a building, concrete has the most important role, which serves as a load-bearing concrete. Because the concrete does have the primary function to support the weight of the concrete application of less well when used to resist gravity. So commonly used reinforcement-steel reinforcement to help in overcoming it, because steel has a tensile strength good endurance. Here we see the two main functions of the concrete in brief
- Withstand the load / compression force
- Closing the reinforcing steel so as not corroded.
Thus the discussion that I can share regarding the classification and the types of concrete and their functions. May be useful for all the readers who read it. Shalom, thank you.
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