Properties, Batching & mixing of Concrete

What is the primary factor that determines the workability of concrete?

• a) Aggregate size

• b) Water-cement ratio

• c) Type of cement

• d) Temperature

Which test is commonly used to measure the workability of concrete?

• a) Compression test

• b) Slump test

• c) Rebound hammer test

• d) Water permeability test

What does a higher water-cement ratio generally lead to?

• a) Higher strength and lower workability

• b) Lower strength and higher workability

• c) Higher strength and higher workability

• d) Lower strength and lower workability

In which concrete batching method are the ingredients measured by volume?

• a) Nominal mix

• b) Design mix

• c) Ready mix

• d) Standard mix

What is the recommended maximum free water-cement ratio for concrete exposed to severe environmental conditions?

• a) 0.65

• b) 0.55

• c) 0.45

• d) 0.35

Which property of concrete refers to its ability to flow and fill formwork completely?

• a) Cohesiveness

• b) Flowability

• c) Consistency

• d) Segregation resistance

What is the main advantage of using weight batching over volume batching?

• a) It's faster

• b) It requires less equipment

• c) It's more accurate

• d) It's less expensive

Which of the following is NOT a factor affecting the durability of concrete?

• a) Cement content

• b) Curing conditions

• c) Color of aggregates

• d) Water-cement ratio

What is the primary purpose of curing concrete?

• a) To increase setting time

• b) To maintain adequate moisture for hydration

• c) To reduce heat of hydration

• d) To prevent segregation

Which batching method involves determining the exact proportions of materials based on specific requirements of a project?

• a) Nominal mix

• b) Standard mix

• c) Design mix

• d) Prescribed mix