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26 Cards in this Set
- Front
- Back
The volumetric method of determining air content of concrete can be used on concrete containing what types of aggregate? |
light weight aggregates, air cooled slag, highly porus aggregates |
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What are the requirements for the tamping rod used in this test method? |
5/8 +- 1/16'' Tamping Rod must be +4'' greater bowl but not more than 24'' |
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What are the requirements for the strike-off bar used in this test method |
1/8 by 3/4 by 12 in. abrasion resistant plastic / high density polyethelene |
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What is the approximate volume of the measuring cup used to add water to the air meter, in relation to the volume of the air meter bowl? |
1% +- .04% |
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What type of alcohol and concentration must be used in this test method? |
Isopropyl Alcohol / 70% |
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A mallet weighing _____ must be used to tap the sides of the bowl after rodding each layer. |
1.25 +- .5lb or 600 +- 200G |
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The maximum size aggregate allowed in this test method is ____ |
1 1/2'' |
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If the concrete sample contains aggregate larger than that allowed for this test, the sample must be |
wet sieved |
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When filling the measuring bowl of the air meter, the concrete must be placed in ____ layers of equal depth |
2 |
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What is the specified number of strokes required when rodding each layer of concrete? |
25 |
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Is it necessary to tap the sides of the measuring bowl after each layer has been rodded. T or F |
True
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The initial quantity of water and alcohol added to the air meter can be poured directly into the neck of the top section of the air meter. T or F |
False |
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The sample of concrete used in this test method must be obtained in accordance with what ASTM Standard? |
ASTM 172 |
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Upon final filling of the air meter with water, what part of the liquid level should be adjusted to the zero mark on the meter? |
Bottom of the meniscus |
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How long should the air meter be inverted and agitated? |
5s intervals for 45seconds |
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How many times does the rolling operating occur? |
3 1 minute each |
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Why is the isopropyl alcohol added to the meter? |
control amount of foam |
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The direct reading of the final liquid level in the neck of the air meter is estimated to the nearest |
.25% |
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If the air content is greater than the 9% range of the meter, add |
h20 |
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In order for an initial meter reading to be valid, the meter must not be leaking, the liquid level must be stabilize within 6 minutes and the foam on the surface of the liquid must not be greater than 2 full percent divisions. T or F |
True |
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If less than 1.25 L [2.5pt] of alcohol are used, the air content is always indicated by the final meter reading. T or F |
F |
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If more than 1.25L [2.5pt] of alcohol are used, the final meter reading is always adjusted using |
alcohol correction factors |
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When large amount of alcohol are used, the direct reading will tend to indicate a _______ air content |
higher |
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At the end of the procedure, the air meter is |
disassemble / inspect content |
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If portions of undistrubed concrete are found in the air meter at the end of the test |
the test isn't valid |
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How much water should you add? |
at least 0.5L [1pt] |