Concrete Technology Questions and Answers - Damp Proofing Admixtures

1. Damp proofing __________ the process of water absorption.
a) Increase
b) Slows
c) Doesn’t effect
d) Depends on the mixture

Answer: b
Explanation: Damp proofing is good for slowing down the rate at which moisture is absorbed.

2. Damp proofing is cheaper in the beginning, but leads to more expensive problems later on.
a) True
b) False

Answer: a
Explanation: Damp proofing is cheaper in the beginning, but leads to more expensive problems later on as compared to water proofing.

3. Damp proofing cracks along with the foundation.
a) True
b) False

Answer: a
Explanation: If the surface has only been damp proofed, the cracks and crevices are also present in the coating of the damp proofing material.

4. Damp proofing __________ resist water well enough.
a) Does
b) Does not
c) Doesn’t effect
d) Depends on the temperature

Answer: b
Explanation: Damp proofing does not resist water well enough to prevent oversaturation from ground water, or excessive and constant humidity.

5. DPC _________ effective used in concretes that are in contact with water under pressure.
a) Does
b) Doesn’t
c) Doesn’t effect
d) Depends on the temperature

Answer: b
Explanation: Many so-called damp proofers are not effective, especially when used in concretes that are in contact with water under pressure.

6. Nomenclature of water proofing agent.
a) PC
b) KIM
c) PCKIM
d) WP

Answer: b
Explanation: Nomenclature of water proofing agent is KIM and PC is the nomenclature of Portland cement.

7. The addition of the admixture to the mix __________ the surface tension.
a) Lowers
b) Higher
c) Don’t affect
d) No change

Answer: a
Explanation: The addition of the admixture to the mix lowers the surface tension of the water thereby assisting in the formation of bubbles.

8.Entrapped air normally exists in the form of relatively _________ air voids.
a) Small
b) Absent
c) Large
d) Medium

Answer: c
Explanation: Entrapped air normally exists in the form of relatively large air voids, which are not dispersed uniformly throughout the mix, entrained air exists in the form of minute disconnected bubbles well distributed throughout the mix.

9. What is water proofing admixtures?
a) Water repellent materials
b) Water fair material
c) Water absorption material
d) Water adsorption material

Answer: a
Explanation: Water proofing admixtures are available in powder, paste or liquid form and may consist of pore filling or water repellent materials.

10. Water proofing admixtures are available in powder, paste or liquid and gaesous form.
a) True
b) False

Answer: b
Explanation: Water proofing admixtures are available in powder, paste or liquid form. It won’t be available un gaseous form.