Concrete technology

Concrete Technology

1. Question 1. What Are All The Types Of Cement?
   Answer :
   • Ordinary Portland cement
   • OPC 33,OPC 43 and OP C53 grade
   • Rapid hardening cement
   • Extra rapid hardening cement
   • Sulphate resisting cement
   • Portland slag cement
   • Quick setting cement
   • Low heat cement
   • Portland pozzolana cement
   • Colored cement
2. Question 2. Differentiate Dry Process And Wet Process Of Manufacturing Cement?
   Answer :
   • Lime stone and clay are ground to fine powder separately and are mixed together.
   • Water is added to make a thick paste which contains 14% of moisture.
   • The paste format are dried and off charged into a rotary kiln.
   • The product obtained often calcination in rotary kiln.
   Process
   • The crushed raw materials are fed in to a ball mill and a little water is added.
   • The steel balls in the ball mill pulverizer the raw material which form a slurry with water.
   • The slurry is passed through storage tanks where the proportioning of compound is adjusted to ensure desired chemical composition.
3. Question 3. Define Batching, What Are All The Methods Of Batching?
   Answer :
   The measurement of materials for making concrete is known as batching. Methods of batching Volume batching Weigh batching.
4. Question 4. What Are All The Raw Materials Of The Cement?
   Answer :
   • Lime
   • Silica
   • Alumina
   • Calcium sulphate
   • Iron oxide
   • Magnesium oxide
   • Sulphur dioxide
   • alkalis
5. Question 5. Write Notes On Steam Curing?
   Answer :
   This approach is widely used in precast concrete units.here the precast units are kept under warm and damp atmosphere of a steam chamber.

1. Question 6. Define Non Destructive Testing?
   Answer :
   Non destructive testing is done on hardened concrete in non destructive testing methods soe properties of concrete are used to estimate strength durability ,elastic parameters,crack depth micro cracks and progressive deterioration of concrete.
2. Question 7. What Are All The Types Of Concrete Test?
   Answer :
   Slump test compressive test split tensile strength
3. Question 8. How Do You Measure Concrete?
   Answer :
   Cubic feet, Cubic yards, Cubic Meter
4. Question 9. What Is The Meaning Of Soil Reinforcement?
   Answer :
   Soil reinforcement is the act of improving soil strength to enable it support or carry more load.
   Two common examples are:
   1. Mixing a soil amendment such as lime into weak clayey soil and re-comPActing to improve soil-bearing caPAcity (often done under the road base in highway construction)
   2. Installing plastic or composite webbing layers (called geo-grid material) alternating with comPActed soil to produce a stronger sloped soil structure (often done on steep roadway embankments to improve strength and stability)
5. Question 10. What Is Aggregate?
   Answer :
   Aggregate is the component of a composite material used to resist compressive stress.

1. Question 11. What Year Was The Keystone Power Plant In Indiana County Constructed?
   Answer :
   1967 began commercial operation on unit 1.
2. Question 12. What Is The Force Exerted By The Tacoma Narrows Bridge?
   Answer :
   The force exerted to the Tacoma narrows bridge was initially the wind resistance. The wind resistance caused the whole bridge to act as a system with forced vibration with damping.
3. Question 13. What Are The Uses Of Alloys In Daily Life And How Are Alloys Made?
   Answer :
   Alloying is not always done to produce a 'superior' material, but to produce materials having a desired requirement in the industry or elsewhere. A classic case is of lead solder (containing lead & tin), in which the melting point of the constituent elements are lowered, not necessarily a desirable property.
   Alloying can be carried out using hot press method (a sheet of material is sandwiched with alloying material), rolling the heated base metal in a drum full of alloying metal powder, using hot spraying, galvanizing (dipping the base in a molten solution of alloying material) etc. Sometimes the alloying material is added in small proportions to the molten base metal (e.g., in production of different types of steel).
4. Question 14. What Is The Worlds Largest Concrete Dam?
   Answer :
   The Grand Coulee Dam is said to be the largest concrete dam. Currently the world's largest concrete dam is the Itaipu Dam, an accomplishment of two neighboring countries, Brazil and Paraguay in South America.
   Though it is not finished yet, the Three Gorges (Sanda pong) Dam on the Yangtze River in China will take over as the largest upon its completion, which is slated for 2009.
5. Question 15. State The Building Codes?
   Answer :
   These codes are the set of specifications to ensure the safety associated with any building construction. These codes are associated with the height, spacing, and installation of the building. These codes play an important role in vacating the building in case of any emergency situations.
   From these interview questions, you will get an idea of the questions interviewer can ask you in the civil engineering position interview. Refer to some more sample questions here and revise all the answers carefully.
6. Question 16. What Are The Steps Involved In The Concreting Process, Explain?
   Answer :
   The major steps involved in the process of concreting are as follows:
   1. Batching
   2. Mixing
   3. Transporting and placing of concrete
   4. Compacting.
   Batching: The process of measurement of the different materials for the making of concrete is known as batching. batching is usually done in two ways: volume batching and weight batching. In case of volume batching the measurement is done in the form of volume whereas in the case of weight batching it is done by the weight.
   Mixing: In order to create good concrete the mixing of the materials should be first done in dry condition and after it wet condition. The two general methods of mixing are: hand mixing and machine mixing.
   Transportation and placing of concrete: Once the concrete mixture is created it must be transported to its final location. The concrete is placed on form works and should always be dropped on its final location as closely as possible.
   Compaction of concrete: When concrete is placed it can have air bubbles entrapped in it which can lead to the reduction of the strength by 30%. In order to reduce the air bubbles the process of compaction is performed. Compaction is generally performed in two ways: by hand or by the use of vibrators.
7. Question 17. Describe Briefly The Various Methods Of Concrete Curing?
   Answer :
   Curing is the process of maintaining the moisture and temperature conditions for freshly deployed concrete. This is done for small duration of time to allow the hardening of concrete. The methods that are involved in saving the shrinkage of the concrete includes:
   1. Spraying of water: on walls, and columns can be cured by sprinkling water.
   2. Wet covering of surface: can be cured by using the surface with wet gunny bags or straw
   3. Ponding: the horizontal surfaces including the slab and floors can be cured by stagnating the water.
   4. Steam curing: of pre-fabricated concrete units steam can be cured by passing it over the units that are under closed chambers. It allows faster curing process and results in faster recovery.
   5. Application of curing compounds: compounds having calcium chloride can be applied on curing surface. This keeps the surface wet for a very long time.
8. Question 18. What Do You Understand By “preset” During The Installation Process Of Bridge Bearings?
   Answer :
   During the installation of bridge bearings the size of the upper plates is reduced to save the material costs. This process is known as preset. Generally the upper bearing plate comprises of the following components:
   1. Length of bearing
   2. 2 x irreversible movement.
   3. 2 x reversible movement.
   The bearing initially is placed right in the middle point of the upper bearing plate. No directional effects of irreversible movement is considered. But since the irreversible movement usually takes place in one direction only the displaced direction is placed away from the midpoint. In such cases the length of the upper plate is equal to the length of the length of the bearing + irreversible movement + 2 x reversible movement.