Vani Institute Interview Questions and Answers

Water is added to concrete after casting to maintain moisture content and achieve early strength and resist creep formation.

• Adding water to concrete after casting helps to prevent excessive moisture loss.

• Maintaining moisture content in concrete is important for proper hydration of cement particles.

• Watering concrete can also help in reducing shrinkage and cracking.

• By providing moisture, the concrete gains strength faster and can resist creep formation.

• Examples of methods to ma...read more

Bleeding and segregation are common issues in concrete construction.

• Bleeding occurs when excess water in the concrete mixture rises to the surface, leaving behind a layer of water.

• Segregation happens when the coarse aggregates separate from the rest of the concrete mixture.

• Both bleeding and segregation can negatively impact the strength and durability of the concrete.

• Proper mix design, adequate compaction, and appropriate curing techniques can help minimize these issues.

Residence: New York, Qualification: Bachelor's degree in Civil Engineering, Hobbies: Reading, Experience: 5 years in planning and scheduling

• Residence: New York

• Qualification: Bachelor's degree in Civil Engineering

• Hobbies: Reading

• Experience: 5 years in planning and scheduling

Curing is necessary for concrete to ensure proper hydration and strength development.

• Curing prevents moisture loss from the concrete, allowing it to maintain its desired water-cement ratio.

• It helps in reducing shrinkage and cracking by providing a controlled environment for the concrete to cure.

• Curing promotes the formation of calcium silicate hydrate (CSH) gel, which contributes to the strength and durability of concrete.

• Proper curing enhances the long-term performance of co...read more

The allowable height for free fall for concrete depends on several factors.

• The allowable height for free fall for concrete is typically specified by the project specifications or industry standards.

• The height is influenced by factors such as the type of concrete mix, slump value, and the presence of reinforcing steel.

• For example, for normal weight concrete with a slump of 3 to 4 inches and no reinforcing steel, the allowable free fall height may be around 5 feet.

• However, for ...read more

M stands for 'Mix' in M20.

• M20 is a designation for a concrete mix with a compressive strength of 20 megapascals (MPa).

• The 'M' in M20 represents the word 'Mix', indicating that it is a mix of cement, sand, and aggregate.

• The number following 'M' in M20 denotes the compressive strength of the concrete mix.

• Different grades of concrete have different compressive strength requirements, and the 'M' designation helps in identifying the mix ratio.

Segregation is the separation of coarse and fine particles in concrete mix, while bleeding is the upward movement of water in fresh concrete.

• Segregation occurs when the coarse aggregates settle down due to gravity, resulting in a non-uniform distribution of particles in the mix.

• Bleeding happens when excess water in the concrete mix rises to the surface, leaving behind a layer of water on top.

• Segregation can lead to a decrease in concrete strength and durability, as well as an...read more