Portland Cement Concrete

Question 1

What types of cement are there?

Answer 1

Polymeric and Mineral

Question 2

What is Polymeric Cement?

Answer 2

It is made up of glues/adhesives and Bitumens

Question 3

What is Mineral Cement?

Answer 3

Calcium and Calcium Silica Compounds

Question 4

Advantage of Concrete

Answer 4

Durable, economical, formed on site, energy efficient, not flammable, thermal resistance, aesthetics, water resistant

Question 5

Disadvantages of Concrete

Answer 5

Brittle, Slow Material Development, low strength to weight ratio, formed on site, volume instability

Question 6

Proportions of Concrete Mixture by Volume

Answer 6

24 % paste (10 % cement and 14 % Water), 36 % fine aggregate, and 40 % coarse aggregate

Question 7

Proportion by Material Cost

Answer 7

19 % Coarse Aggregate, 22 % fine aggregate, and 59 % cement

Question 8

The Major Components of PCC

Answer 8

Lime (CaO), Iron (Fe2O3), Silica (SiO2), and Alumina (Al2O3) according to Jason Weiss

Question 9

Stages of the Cement Clinker Making Process

Answer 9

1 Cement Material enters kiln, 2 Free Water Evaporates, 3 Clay decomposes, 4 Limestone decomposes, 5 Formation of initial compounds, 6 Initial Compound of C2S, 7 Formation of melt, 8 Formation of C3S, 9 Clinker out of the kiln

Question 10

Shorthand Labels

Answer 10

Lime - C, Silica - S, Alumina - A, Ferric Oxide - F, Magnesia - M, Carbon dioxide - C with bar, Water - H, Sulfur Trioxide - S with bar

Question 11

C3S

Answer 11

Tricalcium Silicate

Question 12

C2S

Answer 12

Dicalcium Silicate

Question 13

C3A

Answer 13

Tricalcium Aluminate

Question 14

C4AF

Answer 14

Tetracalcium Aluminoferrite

Question 15

Properties of C3S

Answer 15

Very Common in Cement, reacts quickly with water, Contributes to early age strength, contributes to ultimate strength, medium heat of hydration

Question 16

Properties of C2S

Answer 16

relative in cement, reacts slowly with water, contributes poorly to early age strength, contributes highly to ultimate strength, low heat of hydration

Question 17

Properties of C3A

Answer 17

low amounts in concrete, reacts quickly with water, contributes well to early age strength and average to ultimate strength, High heat of hydration

Question 18

Order of heat of Hydration

Answer 18

Highest to Lowest, III, I, II

Question 19

Stages of Concrete Evolution

Answer 19

Stage 1 - Rapid Heat Evolution, Stage 2 - Dormant Period, Stage 3 - Accelerating Stage, Stage 4 - Deceleration Stage, Stage 5 - Steady State

Question 20

What is Durability?

Answer 20

The ability to resist weathering action, chemical attack, abrasion, or other deterioration

Question 21

Factors that Affect Durability

Answer 21

freeze-thaw, ASR, and corrosion

Question 22

Factors that Affect Durability

Answer 22

freeze-thaw, ASR, and corrosion

Question 23

Alkali-Silica Reactivity Contributes to

Answer 23

swelling when water is present causing cracking and spalling

Question 24

Ways to reduce ASR

Answer 24

• limit Alkali Source
• limit reactive aggregate
• limit moisture
• air entrainment
• Lithium Additives