Design and Control of Concrete Mixtures 16th Edition

Question 1

What is the minimum thickness of a control joint placed in a 6-inch-thick concrete slab on ground?

Answer 1

1 ½ inches

Formula: 1/4th of the depth of the slab.

Question 2

Concrete will continue to strengthen with age over time as long as the relative humidity of concrete remains above:

Answer 2

80

Design and Control of Concrete Mixtures Page 274

Question 3

What type of Portland cement should be used in a massive concrete placement such as a gravity dam (Low heat hydration)?

Answer 3

Type IV

Design and Control of Concrete Mixtures Page 110

Question 4

What type of Portland Cement should be used in a concrete mix when the forms must be removed early?

Answer 4

Type III

Design and Control of Concrete Mixtures Page 110

Question 5

What is the effect of algae in mixing water used for concrete?

Answer 5

Reduced strength

Design and Control of Concrete Mixtures Page 179

Question 6

What type of concrete joint is used for both horizontal and vertical movement at adjoining concrete surfaces?

Answer 6

Isolation joint

Design and Control of Concrete Mixtures Page 437

Question 7

What is the effect of high heat in concrete?

Answer 7

Reduced slump

Design and Control of Concrete Mixtures Page 467

Question 8

The abrasion resistance of concrete is dependent upon:

Answer 8

Adequate curing

Design and Control of Concrete Mixtures Page 542

Question 9

What is the minimum density for lightweight insulating concrete in pounds per cubic foot?

Answer 9

15

Design and Control of Concrete Mixtures Page 554

Question 10

Concrete cover is the minimum distance from the:

Answer 10

Outside of the reinforcing bar to face of concrete

Design and Control of Concrete Mixtures – Older Edition

Question 11

What is the finish calculation for figuring the cubic yards of concrete if the beginning calculation is Length x?

Answer 11

Width x Depth (in feet) divided by 27

Design and Control of Concrete Mixtures Calculation

Question 12

What type of concrete has a low heat of hydration?

Answer 12

Type IV

Design and Control of Concrete Mixtures Page 110

Question 13

What type of concrete has a moderate sulfate resistance?

Answer 13

Type II

Design and Control of Concrete Mixtures Page 110

Question 14

What is the maximum slump for lightweight concrete?

Answer 14

5 inches

6 inches Design and Control of Concrete Mixtures Page 553

Question 15

Why should you use a chute for placing concrete instead of dropping it in place?

Answer 15

Helps concrete to not separate (without segregation)

Design and Control of Concrete Mixtures Page 404

Question 16

Which admixture is added in concrete to accelerate the rate of hydration and increase strength development at an early age?

Answer 16

Accelerating admixture

Design and Control of Concrete Mixtures Page 222

Question 17

On concrete thickness up to about seven inches, which of the below are true about air content to slump?

Answer 17

Air content increases as slump increases

Design and Control of Concrete Mixtures Page 269

Question 18

Which of the below would increase the abrasive strength of concrete?

Answer 18

Low water-cement ratio
Steel - troweled surface
Harder aggregate
All of these

Design and Control of Concrete Mixtures Page 283

Question 19

What is the purpose of using vibrators when doing concrete work?

Answer 19

Get rid of air voids
Consolidates the concrete
Both 1 and 2

Design and Control of Concrete Mixtures Page 423

Question 20

Tools used for finishing air-entrained concrete should be constructed from which of the below?

Answer 20

Aluminum or magnesium

Design and Control of Concrete Mixtures Page 429

Question 21

Normal weight and lightweight concrete exposed to freezing and thawing or deicing chemicals shall be:

Answer 21

Air entrained

Design and Control of Concrete Mixtures Page 359

Question 22

Hotter than normal temperatures when pouring concrete has what consequences (or “What is true” about pouring concrete in hot weather?)

Answer 22

Increased slump loss
Increased tendency for cracking
Long term strength loss
All of the above

Design and Control of Concrete Mixtures Page 467

Question 23

Freezing temperatures have what effect (or it may have asked what is true) on fresh concrete

Answer 23

Concrete that has been frozen will not be as impermeable as concrete that wasn’t frozen

Design and Control of Concrete Mixtures Page 482