MIX design

Question 1

Basic requirements for plastic concrete?

Answer 1

1. Concrete has to be workable enough to flow into all parts of formwork and around reinforcement.
2. No segregation or bleeding
3. Full compaction must be achieved
4. the required surface finish must be achieved

Question 2

Basic requirements for hardened concrete?

Answer 2

1. Adequate durability
2. Designed strength
3. designed surface finish

Question 3

What does workability depends on?

Answer 3

1. Slump
2. Compacting factor
3. Vebe time
4. Flow measurement

Question 4

What does durability depends on?

Answer 4

1. Full compaction
2. Adequate cement content
3. Low w-c ratio

Question 5

Steps to design concrete mix.

Answer 5

1. Determine w-c ratio
2. Determine h2o content to achieve desired workability
3. determine cement ratio
   4, Determine total aggregate
   .5. Determine proportion of fine aggregate in total aggregate.

Question 6

Types of special concretes.

Answer 6

Pumpable concrete, Self compacting concrete, lightweight aggregate concrete,