Portland Cement (Lecture 4)

Question 1

Type I Portland Cement

Answer 1

For General Use. No limits are placed on any four principal compounds

Question 2

Type II Portland Cement

Answer 2

Moderate Sulfate resistance and moderate heat of hydration. Spec limits the C3A content to a max 8%

Question 3

Type III Portland Cement

Answer 3

High Early Strength. C3A content is limited to max of 15%

Question 4

Type IV Portland Cement

Answer 4

Low heat of hydration. max limits of 35% on C3S and 7% on C3A. Minimum 40% C2A.

Question 5

Type V Portland Cement

Answer 5

High sulfate resistance. Max limit 5% on C3A.

Question 6

Air entraining Portland Cement

Answer 6

Type IA, IIA, IIIA.

Question 7

Pozzolan

Answer 7

siliceous or siliceous and aluminous material that has no cementing property but reacts with water to create Calcium hydroxide to form cementious product.

Question 8

Properties of Pozzolan

Answer 8

1) Slow reaction
2) consumes CaOH
3) Fills large capillary spaces making concrete less permeable and more durable.

Question 9

Blast Furnace Slag

Answer 9

Nonmetallic waste product from manufacturing of iron and steel

Question 10

Granulated Slag

Answer 10

Glassy Product formed by rapid cooling of molten blast furnace slag.
Is self cementing

Question 11

Portland Blast Furnace Slag Cement

Answer 11

Type IS. blend of portland cement with 25-70% by weight of granulated blast furnace slag.

Question 12

Portland Pozzolan Cement

Answer 12

Type IP & P. blend of portland cement with 15-40% fine pozzolan by weight.
Type P has lower early strength, used when high strength early is not required.

Question 13

Effect of Pozzolan and Blast Furnace Slag on durability of concrete

Answer 13

• Water resistance increased
• Permeability is reduced
• Sulfate resistance increased
• Alkali aggregate expansion is reduced

Question 14

Colored cement

Answer 14

formed by adding pigments to white cement or using clinkers. similar to normal portland cememnt

Question 15

White cement

Answer 15

used to produce architectural concrete where white is desired. Formed by reducing iron content.

Question 16

Hydraulic cement

Answer 16

hardens by reacting with water to form water resistant product. Portland cement is hydraulic.

Question 17

Non hydraulic cement

Answer 17

reacts with water to form product which is not stable in water. Hydration product may act with air to form water resistant product. EX. Quicklime

Question 18

Who invented portland cement?

Answer 18

Joseph Aspdin

Question 19

Why was portland cement named so?

Answer 19

Named after the concrete it produced resembling the color of the natural limestone quarried on the isle of portland.

Question 20

What is the largest size of portland cement?

Answer 20

Finer than 200 sieve (75micrometers)

Question 21

What is the typical specific gravity of portland cement

Answer 21

3.15

Question 22

What is the typical unit weight of portland cement

Answer 22

94pcf

Question 23

How much does a bag of portland cement weigh

Answer 23

94lbs

Question 24

What are the four main oxides in portland cement

Answer 24

Calcium Oxide
Silicon Oxide
Aluminum Oxide
Iron Oxide

Question 25

What are the four main compounds that form portland cememnt

Answer 25

Tricalcium Silicate- C3S Dicalcium Silicate- C2S Tricalcium Aluminate- C3A Tetracalcium Aluminoferrite- C4AF

Question 26

What chemical abbreviation is C

Answer 26

calcium oxide

Question 27

What chemical abbreviation is S

Answer 27

Silicon Oxide

Question 28

What chemical abbreviation is A

Answer 28

Aluminum Oxide

Question 29

What chemical abbreviation is F

Answer 29

Iron oxide

Question 30

What are the properties of C3S

Answer 30

Hydrates and hardens rapidly | responsible for initial set and early strength

Question 31

What are the properties of C2S

Answer 31

Hydrates and hardens slowly | Contributes to strength increase beyond 1 week

Question 32

What are the properties of C3A

Answer 32

Hydrates rapidly and gives off a lot of heat Contributes slightly to early strength More susceptible to sulfate attacks which cause expansion and cracking

Question 33

What are the properties of C3AF

Answer 33

Contributes little to strength. Reduces clinkering temp in production of cement which reduces cost

Question 34

Is cement hydration endothermic or exothermic?

Answer 34

Exothermic (heat is generated)

Question 35

What does C3S and C2S produce?

Answer 35

Calcium Silicate Hydrate- strong and stable in water | Calcium Hydroxide- soluble in water