The
science which deals with the geometry of motion of fluids without reference to
the forces motion is known as Hydrokinematics. On the contrary the science
which deals with the action of the forces employed in producing or Hydrokinematics
or simply kinetics
Tuesday, September 23, 2014
Sunday, September 21, 2014
PLATE GIRDERS
Plate girder is a built-up beam using plates and angles and connecting them by rivets or welding. These are more economical for short spans and heavy loads.
ABRASION
Abrasion is process of wear or removal of the surface of a solid material as a result of relative movement of other solid bodies in contact with it.
Friday, September 19, 2014
CARBONATION
Carbonation is the process of transformation of the free
alkali and alkali-earth hydroxides existent in the cement matrix into
carbonates, due to a reaction with carbon dioxide available in the atmosphere.
Thursday, September 18, 2014
GRAVITY DAMS
Gravity Dams :
The rigid dam which is constructed either with stone or brick masonry or mass concrete, is called a solid gravity dam. As solid gravity dams resist the overturning moments due to all external forces i.e. water pressure, silt pressure, etc. by its own weight only these are known as solid gravity dams.
Advantages:
1. They are suitable in steep valleys where earth dams tends to slip.
2. They don't fail easily, even if the tends to fail it can be predicted.
3. The surplus water can be discharged through the sluices provided.
4. These dams are strong in foundations and build to more height.
5. The sedimentation in the reservoir can be removed through the sluices.
6. The cost of maintenance is very less.
Disadvantages:
1. They require strong foundation.
2. Initial cost of construction is high.
3. Once dam is constructed it cannot be raised further.
4. For the supervision it requires a skilled labour.
The rigid dam which is constructed either with stone or brick masonry or mass concrete, is called a solid gravity dam. As solid gravity dams resist the overturning moments due to all external forces i.e. water pressure, silt pressure, etc. by its own weight only these are known as solid gravity dams.
Advantages:
1. They are suitable in steep valleys where earth dams tends to slip.
2. They don't fail easily, even if the tends to fail it can be predicted.
3. The surplus water can be discharged through the sluices provided.
4. These dams are strong in foundations and build to more height.
5. The sedimentation in the reservoir can be removed through the sluices.
6. The cost of maintenance is very less.
Disadvantages:
1. They require strong foundation.
2. Initial cost of construction is high.
3. Once dam is constructed it cannot be raised further.
4. For the supervision it requires a skilled labour.
AGGREGATES:
AGGREGATES:
Aggregates are the inert materials which when bound together by cement form concrete. They consist of materials such as pebbles, gravel crushed stone, sand etc.. Aggregates are commonly classified into sizes, fine and coarse. The material which retained on 4.75 mm IS sieve is classified as coarse aggregate. Whereas materials passing through this sieve is known as fine aggregate. Aggregates used for concrete work must be hard, strong, dense durable, clean and free from adherent coatings.
Wednesday, September 17, 2014
EARTH DAMS
EARTH DAMS
The dams which are build of rock, gravel, sand, silt or clay in various combinations by placing rolling or tamping these materials, are called earth dams or non rigid dams.
Advantages of Earth Dams :
In-spite of the structural incompressibility of earth and water many earth dams have been constructed with various types of earth and rock with stable conditions. The main advantages of earth dams are
1. Availability of Earth materials
2. Earth can be excavated, transported,compacted, with machineries easily
3. Earth dams are suited to the sites where a masonry dam cannot be used for structural reasons. These dams can be constructed even on compressible foundation. The intensity of foundation stress
due to earth is less than that due to solid masonry. The horizontal water pressure on the dams, is distributed over greater area because of greater base width and hence, the danger of sliding on a weak foundation is minimised.
4. The most important advantage of an earth dam instead of masonry, is its lesser cost, It has been observed that the total cost of an earth dam, is roughly one half of concrete dam.
Disadvantages:
However the earth and rock fill dams possess the following disadvantage
1. Non availability of the materials at or near the dam site
2. The grater maintenance cost as compared to good concrete dam
3. Earth dams are unsuitable for spill ways
Components of Earth Dams :
An Earth Dam consist of three basic components they are
1. Foundation
2. Core or Membrane
3. Shell
1. Foundation : It consist of either earth or rock and provides the support for the embackment and resist both vertical and horizontal loads. It also resist the seepage on the flow of water beneath the dam.
2. Core or Membrane : It holds back the free water of the dam reservoir. It is located either at the centre or upstream from the centre of the dam. In case of rock fill dams the core is provided on the upstream face.
3. Shell : It provides structural support for the core and distributed the load over the foundation, The dams which are constructed of the same materials are called homogeneous dams.
The dams which are build of rock, gravel, sand, silt or clay in various combinations by placing rolling or tamping these materials, are called earth dams or non rigid dams.
In-spite of the structural incompressibility of earth and water many earth dams have been constructed with various types of earth and rock with stable conditions. The main advantages of earth dams are
1. Availability of Earth materials
2. Earth can be excavated, transported,compacted, with machineries easily
3. Earth dams are suited to the sites where a masonry dam cannot be used for structural reasons. These dams can be constructed even on compressible foundation. The intensity of foundation stress
due to earth is less than that due to solid masonry. The horizontal water pressure on the dams, is distributed over greater area because of greater base width and hence, the danger of sliding on a weak foundation is minimised.
4. The most important advantage of an earth dam instead of masonry, is its lesser cost, It has been observed that the total cost of an earth dam, is roughly one half of concrete dam.
Disadvantages:
However the earth and rock fill dams possess the following disadvantage
1. Non availability of the materials at or near the dam site
2. The grater maintenance cost as compared to good concrete dam
3. Earth dams are unsuitable for spill ways
Components of Earth Dams :
An Earth Dam consist of three basic components they are
1. Foundation
2. Core or Membrane
3. Shell
1. Foundation : It consist of either earth or rock and provides the support for the embackment and resist both vertical and horizontal loads. It also resist the seepage on the flow of water beneath the dam.
2. Core or Membrane : It holds back the free water of the dam reservoir. It is located either at the centre or upstream from the centre of the dam. In case of rock fill dams the core is provided on the upstream face.
3. Shell : It provides structural support for the core and distributed the load over the foundation, The dams which are constructed of the same materials are called homogeneous dams.
Subscribe to:
Posts (Atom)