CONSTRUCTION MATERIALS EXAM #2 QUESTIONS AND ANSWERS

CONSTRUCTION MATERIALS EXAM
#2 QUESTIONS AND ANSWERS
What are the four components of concrete? - ANSWERS--1) Cement
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2) Water
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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-- 8l 8l 8l 8l


when added to PCC, they have cementitious characteristics. can reduce PCC by 20
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% and maintain the same strength.
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Honeycombing - ANSWERS--when you can see the air pockets in concrete, bad 8l 8l 8l 8l 8l 8l 8l 8l 8l 8l 8l




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-- 8l 8l


the property of freshly mixed concrete that determines its working characteristics (i.e.
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the ease it can be mixed, placed, compacted and finished.)
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Factors Affecting Workability - ANSWERS--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
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Hydration - ANSWERS-- 8l 8l


the chemical reaction between cement and water in which new compounds with stren
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gth 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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Curing - ANSWERS-- 8l 8l


maintenance of a satisfactory moisture content and temperature in concrete for a suit
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