ACI Aggregate Testing Technician
Performance Checklist:
Sampling of Aggregates:
Flowing Aggregate Stream (Bins or Belt Discharge)
5 steps - (correct answer) -1. Use a device that will hold
the required amount of material without overflowing.
2. Take each increment from the entire cross section of
the material discharge stream
3. Obtain a minimum of three approximately equal
increments.
4. Combine the increments to form a field sample.
5. Ensure that the size of the field sample equals or
exceeds the approximate minimum mass needed or stated
in Table 1.
,Performance Checklist:
Sampling of Aggregates:
Conveyor Belt
7 Steps - (correct answer) -1. Stop the conveyor belt and
insert two templates conforming to the shape of the belt
into the aggregate steam.
2. Space the templates so the material between will yield
an increment of the required mass.
3. Carefully scoop the material between the templates
into a suitable container.
4. Collect the fines with a brush and dust pan and add to
the container.
5. Obtain a minimum of three approximately equal
increments.
6. Combine the increments to form a field sample.
, 7. Ensure that the size of the field sample equals or
exceeds the approximate minimum mass needed or stated
in Table 1.
Performance Checklist:
Sampling of Aggregates:
Stockpiles (Manual Sampling)
7 Steps - (correct answer) -Course Aggregate
1. Shove a board vertically into the pile just above the
sampling point.
2. Take increments from the top third, mid-point, and
bottom third of the volume of the pile.
Fine Aggregate
3. Remove the outer layer and sample from the material
beneath.
4. Insert the appropriate sampling tube randomly to
extract the increments.
5. Obtain a minimum of five increments.
Performance Checklist:
Sampling of Aggregates:
Flowing Aggregate Stream (Bins or Belt Discharge)
5 steps - (correct answer) -1. Use a device that will hold
the required amount of material without overflowing.
2. Take each increment from the entire cross section of
the material discharge stream
3. Obtain a minimum of three approximately equal
increments.
4. Combine the increments to form a field sample.
5. Ensure that the size of the field sample equals or
exceeds the approximate minimum mass needed or stated
in Table 1.
,Performance Checklist:
Sampling of Aggregates:
Conveyor Belt
7 Steps - (correct answer) -1. Stop the conveyor belt and
insert two templates conforming to the shape of the belt
into the aggregate steam.
2. Space the templates so the material between will yield
an increment of the required mass.
3. Carefully scoop the material between the templates
into a suitable container.
4. Collect the fines with a brush and dust pan and add to
the container.
5. Obtain a minimum of three approximately equal
increments.
6. Combine the increments to form a field sample.
, 7. Ensure that the size of the field sample equals or
exceeds the approximate minimum mass needed or stated
in Table 1.
Performance Checklist:
Sampling of Aggregates:
Stockpiles (Manual Sampling)
7 Steps - (correct answer) -Course Aggregate
1. Shove a board vertically into the pile just above the
sampling point.
2. Take increments from the top third, mid-point, and
bottom third of the volume of the pile.
Fine Aggregate
3. Remove the outer layer and sample from the material
beneath.
4. Insert the appropriate sampling tube randomly to
extract the increments.
5. Obtain a minimum of five increments.
