Technician Grade I Certification
Exam (Latest Update )
Questions & Answers | Grade A |
100% Correct
Question:
Vibration of the concrete sample is not allowed when the slump of the
concrete exceeds ___.
Answer:
3 in. (75 mm)
Question:
In rodding the sample, how deep should the rod penetrate each layer?
Answer:
Rod bottom layer to full depth; rod second and final layer penetrating the
previous layer about 1 in. (25 mm)
,Question:
After rodding each layer, what should be done to the measure before adding
another layer of concrete?
Answer:
Tap the sides of the measure smartly 10-15 times with the mallet
Question:
When consolidating the concrete by vibration, how many times should the
vibrator be inserted into each layer?
Answer:
3
Question:
What tools may be used to strike off the top surface of the concrete following
consolidation of the final layer?
Answer:
A strike-off bar; a metal, glass, or acrylic plate
,Question:
What must be done if there is a slight deficiency in the quantity of concrete in
the measure following consolidation of the final layer?
Answer:
Add a quantity of representative concrete before strike off
Question:
What must be done if there is an excessive amount of concrete in the measure
following consolidation of the final layer?
Answer:
Remove a representative portion of the excess concrete with a trowel or scoop
before strike off
Question:
The volumetric method of determining air content of concrete can be used on
concrete containing what types of aggregate?
Answer:
All types of aggregate
, Question:
What are the requirements for the tamping rod used in this test method?
Answer:
Round, straight 5/8 in. (16 mm) +- 1/16 in. (2 mm) diameter rod at least 4 in.
(102 mm) greater in length than the depth of the bowl being used, with the
tamping end rounded to a hemispherical tip of the same diameter, made of
steel, high-density polyethylene, or other plastic of equal or greater abrasion
resistance.
Question:
What are the requirements for the strike-off bar used in this test method?
Answer:
Flat, straight steel bar at least 1/8 by 3/4 by 12 in. (3 by 20 by 300 mm) or a flat,
straight high-density polyethylene bar, or other plastic of equal or greater
abrasion resistance, at least 1/4 by 3/4 by 12 in. (6 by 20 by 300 mm)
Question:
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?
Answer:
1.00% +- 0.04%