1. If compaction factor of concrete is .90, then workability is ____________
a) Low
b) Very low
c) Medium
d) High
Explanation: At the less workable end of this group, manually compacted flat slabs using crushed aggregates. Normal reinforced concrete manually compacted and heavily reinforced sections with vibration.
2.A compaction factor of .85 for a cement concrete sample indicates ___________
a) Low workability
b) Medium workability
c) Good workability
d) Very good workability
Explanation: Roads vibrated by hand-operated machines. At the more workable end of this group, concrete may be manually compacted in roads using aggregate of rounded or irregular shape.
3. Adding water increases __________
a) Workability
b) Strength
c) Fame
d) Quality
Explanation: Adding water increases workability because it is inversely proportional to the workability
4. Why Shape and texture of aggregates is a must?
a) Smooth surfaces give better workability
b) Smooth surfaces give poor workability
c) Rough surfaces give better workability
d) Rough surfaces give poor workability
Explanation: The use of smooth and rounded, rather than irregularly shaped aggregate also increases workability.
5. How many types of tests are there to find workability?
a) 3
b) 4
c) 5
d) 6
Explanation: There are 5 types of test to find the workability of a concrete i.e. slump test, compacting factor test, flow table test, vebe test, Kelly ball test.
6. These test find workability __________
a) Directly
b) Indirectly
c) 0
d) Equals to the weight of the cement
Explanation: Unfortunately, there are no accepted tests, which can measure directly the workability
7. Workability of concrete is measured by __________
a) Vicat apparatus test
b) Slump test
c) Minimum void method
d) Talbot Richard test
Explanation: Work ability of concrete is measured by slump cone test, compaction factor test. Slump cone is used for medium work ability. For high work abilities it is not accurate.Slump values vary from 0 mm to 300 mm.
8. Which test gives good results for rich mixes?
a) Slump test
b) Compacting factor test
c) Flow table test
d) VeBe test
Explanation: This is a test used extensively in site work all over the world. Very useful in detecting variations in the uniformity of a mix of given nominal proportions.
9. Which test used for low workable concretes?
a) Slump test
b) Compacting factor test
c) Flow table test
d) VeBe test
Explanation: The degree of compaction, called compacting factor, is measured by the density ratio, i.e. the ratio of the density of actually achieved in the test to the density of the same concrete fully compacted.
10. Which test Used for high workable concretes?
a) Slump test
b) Compacting factor test
c) Flow table test
d) VeBe test
Explanation: Compacting factor test used for high workable concretes. It measures the diameter of spread after vibration.