Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

SKT 3E2X1 > Volume 1, Unit 3 > Flashcards

Volume 1, Unit 3 Flashcards

1
Q

What are the three soil horizons? What are they made of?

A

A, B and C horizons.
The “A” horizon is made up primarily of organic materials.
The “B” horizon is made up of different materials, such as sand, gravel, silt, and clay.
The “C’ horizon is rock in its natural state.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why are “A” horizon soils not used in any phase of construction?

A

Because they are spongy, drain poorly, and do not compact.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which soil horizon is the base for all types of pavement construction?

A

The “B” horizon.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is another name for the “C” horizon? Why?

A

It is sometimes called parent material because it is where “B” horizon material comes from.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is meant by the term plasticity?

A

The ability of a soil to mold into shapes without cracking or appreciable volume change.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a sieve? How are sieve sizes designated?

A

A screen attached across the end of a cylindrical metal frame; by screen opening size.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define the term soil gradation.

A

The distribution of different size groups within the soil sample.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Poorly graded soil may be uniform-graded or gap-graded. What do these terms mean?

A

In uniform-graded soil, most particles are about the same size; in gap-graded soil, at least one particle size is missing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two types of stabilization?

A

Mechanical and chemical.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why should you mechanically stabilize a subgrade?

A

To improve the drainage or compaction characteristics of a soil.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does chemical stabilization do for soil?

A

It cements the soil into a hard mass, and it changes the soil to make it more suitable for construction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the four main types of chemicals used for stabilization?

A

Portland cement, bituminous materials, calcium chloride, and lime.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does calcium chloride increase soil stability?

A

By controlling moisture content. It absorbs moisture from the air, thus keeping the soil damp.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How much calcium chloride is added to each square yard of soil (one inch deep) to stabilize subgrade?

A

Half a pound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What pieces of equipment are designed specifically for compaction work?

A

Sheepsfoot roller, pneumatic-tired roller, and steel-wheel roller.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of soil is compacted best when saturated with water?

A

Sand or sandy gravel.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Besides rollers, what other type of equipment furnishes some form of vibration on soils with low moisture content?

A

Construction equipment, such as tractors and trucks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the purpose of a blanket or insulating course?

A

To help prevent plastic soils from working up into the base course and help reduce frost action.

19
Q

What is used to center the bubble of the bull’s-eye level?

A

Leveling screws on a triangular footplate.

20
Q

How is the compensator suspended on the self-leveling level?

A

On fine, nonmagnetic wires.

21
Q

When should you start maintaining and caring for your engineer level?

A

Immediately upon receipt.

22
Q

Why should most leveling instruments be set up in the shade?

A

Because the level is highly susceptible to expansion and contraction from direct sunlight.

23
Q

What are the three cardinal rules of surveying?

A

Never set up the tripod without finding good footings and setting the legs firmly, never leave the setup instrument unattended, and never straddle the tripod legs.

24
Q

How is the tripod legs of the leveling instrument set on sloping surfaces?

A

With two legs downhill.

25
Q

When leveling the engineer level, how many times should you turn the instrument 90° then back to its original position, before you turn it 180° from its original position?

A

As many as necessary (until the bubble remains centered in both positions).

26
Q

After leveling is complete, how many leveling screws must bear firmly against the leveling head of the engineer level?

A

All three.

27
Q

Describe what a leveling rod is and for what is it used.

A

A graduated pole or stick with a movable marker, and it is used to measure differences in elevation.

28
Q

List the two general classes of leveling rods.

A

Self-reading and target rods.

29
Q

What do the large red marks represent on the Philadelphia rod?

A

Whole foot marks.

30
Q

Why is there an advantage in using a target rod to measure vertical distances?

A

Mistakes in reading the rod are less likely.

31
Q

What should you do if you cannot see the next lower foot mark through the level instrument?

A

Signal or ask the rod-person to raise for red.

32
Q

When using a leveling instrument to measure distances, what can the rod person do to ensure that the rod is vertical?

A

Wave the rod.

33
Q

Define the term elevation.

A

The height of a point or a particular spot above or below a reference line.

34
Q

Once a bench mark is established, what is the first thing you need to do to determine an elevation?

A

Figure the height of the leveling instrument.

35
Q

What are hub stakes used for when checking ground spot for desired grade with a level?

A

To give the exact elevation of the finished grade.

36
Q

Which type of turning point should you use on sandy soil? On firm ground?

A

Turning plate; turning pin.

37
Q

The rotating beam from the laser level strikes the receiver how many times per minute?

A

Six hundred.

38
Q

What does GPS stand for?

A

Global Positioning System.

39
Q

A GPS reference receiver is set up on what type of point?

A

Surveyed.

40
Q

Why does GPS on board computer require a detailed computer design of the site?

A

The design is used to compute the cut or fill at any particular location using elevation data from the GPS.

41
Q

What type of slight tolerance projects is the GPS system not well suited for?

A

Tolerances of less than ¼ inch from finished elevation.

42
Q

What is a line level used for?

A

To check whether two points are level, such as in elevation.

43
Q

Why should you not use a line level with over 25 feet of cord?

A

Because the weight of the level causes the line to slack and you will get an inaccurate elevation reading.

44
Q

What types of small projects are carpenter’s levels used with?

A

Patios and sidewalks.

SKT 3E2X1 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions