CONSTRUCTION MATERIALS EXAM
#2 QUESTIONS AND ANSWERS
What are the four components of concrete? - ANSWERS--1) Cement
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2) Water
7b
3) Fine Aggregate
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4) Coarse Aggregate
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Mortar - ANSWERS--cement in between bricks in walls
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Grout - ANSWERS--stuff in between tiles
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Supplementary cementitious materials - ANSWERS-- 7b 7b 7b 7b
when added to PCC, they have cementitious characteristics. can reduce PCC by 2
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0% and maintain the same strength.
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Honeycombing - ANSWERS--when you can see the air pockets in concrete, bad
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Advantages of Reducing Water Content - ANSWERS--1) Increased strength
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2) Lower permeability
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3) Increased weathering resistance
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4) Better concrete bond
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5) Reduced drying shrinkage and cracking
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6) Less volume change from wetting to drying
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Workability - ANSWERS-- 7b 7b
the property of freshly mixed concrete that determines its working characteristics (i
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.e. the ease it can be mixed, placed, compacted and finished.)
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Factors Affecting Workability - ANSWERS--
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1) Method and duration of transportation
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2) Quantity and characteristics of cementing materials
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3) Concrete consistency (slump)
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4) Aggregate grading, shape and surface texture
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5) % entrained air
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6) Water content
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7) Concrete and ambient air temperature
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8) Admixtures
7b
Hydration - ANSWERS-- 7b 7b
the chemical reaction between cement and water in which new compounds with st
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rength producing properties are formed
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Heat of Hydration - ANSWERS--
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the heat given off during the chemical reaction as the cement hydrates
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#2 QUESTIONS AND ANSWERS
What are the four components of concrete? - ANSWERS--1) Cement
7b 7b 7b 7b 7b 7b 7b 7b 7b
2) Water
7b
3) Fine Aggregate
7b 7b
4) Coarse Aggregate
7b 7b
Mortar - ANSWERS--cement in between bricks in walls
7b 7b 7b 7b 7b 7b 7b
Grout - ANSWERS--stuff in between tiles
7b 7b 7b 7b 7b
Supplementary cementitious materials - ANSWERS-- 7b 7b 7b 7b
when added to PCC, they have cementitious characteristics. can reduce PCC by 2
7b 7b 7b 7b 7b 7b 7b 7b 7b 7b 7b 7b
0% and maintain the same strength.
7b 7b 7b 7b 7b
Honeycombing - ANSWERS--when you can see the air pockets in concrete, bad
7b 7b 7b 7b 7b 7b 7b 7b 7b 7b 7b
Advantages of Reducing Water Content - ANSWERS--1) Increased strength
7b 7b 7b 7b 7b 7b 7b 7b
2) Lower permeability
7b 7b
3) Increased weathering resistance
7b 7b 7b
4) Better concrete bond
7b 7b 7b
5) Reduced drying shrinkage and cracking
7b 7b 7b 7b 7b
6) Less volume change from wetting to drying
7b 7b 7b 7b 7b 7b 7b
Workability - ANSWERS-- 7b 7b
the property of freshly mixed concrete that determines its working characteristics (i
7b 7b 7b 7b 7b 7b 7b 7b 7b 7b 7b
.e. the ease it can be mixed, placed, compacted and finished.)
7b 7b 7b 7b 7b 7b 7b 7b 7b 7b
Factors Affecting Workability - ANSWERS--
7b 7b 7b 7b
1) Method and duration of transportation
7b 7b 7b 7b 7b
2) Quantity and characteristics of cementing materials
7b 7b 7b 7b 7b 7b
3) Concrete consistency (slump)
7b 7b 7b
4) Aggregate grading, shape and surface texture
7b 7b 7b 7b 7b 7b
5) % entrained air
7b 7b 7b
6) Water content
7b 7b
7) Concrete and ambient air temperature
7b 7b 7b 7b 7b
8) Admixtures
7b
Hydration - ANSWERS-- 7b 7b
the chemical reaction between cement and water in which new compounds with st
7b 7b 7b 7b 7b 7b 7b 7b 7b 7b 7b 7b
rength producing properties are formed
7b 7b 7b 7b
Heat of Hydration - ANSWERS--
7b 7b 7b 7b
the heat given off during the chemical reaction as the cement hydrates
7b 7b 7b 7b 7b 7b 7b 7b 7b 7b 7b