Concrete Technology Practice Test 3

1. A value less than 10 signifies an exceptionally _________ while above 35 would normally be regarded as _________

Strong aggregates, strong aggregates

Weak aggregates, strong aggregates

Strong aggregates, weak aggregates

Weak aggregates, weak aggregates

2. Classification of admixtures are classified into ________ types.

3. What is the permissible limits for construction of sulphates in water?

500mg/l

2000mg/l

1000mg/l

200mg/l

4. Which of the following statement is incorrect about the function of admixtures?

To enhance the workability

To reduce the segregation in grout and concrete mixers

To retard the initial set, to keep concrete workable for a shorter time for placement

To accelerate the initial set of concrete, to speed up the rate of development of strength at early ages

5. Where do we use plasticizers?

Where high degree of workability is required

Where very low degree of workability is required

Where medium degree of workability is required

Where low degree of workability is required

6. Mid-range water reducers result in at least _________ %.

7. Damp proofing is cheaper in the beginning, but leads to more expensive problems later on.

True

False

8. Which one is an anionic surfactants?

Carbohydrates

Polyglycol esters

Hydroxylated carboxylic acids

Lignosulphonates

9. Which machine is preferred for abrasion test?

Los Angeles

Vicat’s mould

Elongation Gauge

Flakiness Gauge

10. What is water proofing admixtures?

Water absorption material

Water adsorption material

Water repellent materials

Water fair material