EXAM #2 Flashcards
The BTU is the amount of heat required to raise the temperature of one cu. ft. of air:
55˚
What is rock that is easily dislodged by bars and wedges called?
Common Rock
What is the minimum time of mixing ingredients for asphalt concrete at the batch plant usually?
30 seconds
Vibrators or tampers on the paver are used to get aggregate particles oriented into position. The mixture reaches about_____ %of its eventual density.
80%
There are ___ square feet in an acre.
43,560
What is done with the roots and rocks when clearing and grubbing is required to establish a finishing grade?
Permission is obtained to remove them and dispose of them
Rounded gravel provides displacement better under rollers than rough-textured crushed rock. Gradings with an excess of material passing the ___ sieve can be hard to compact.
No. 4
What is considered the safe distance from a magazine for explosives to be opened?
50 feet
Foundation wall footings for a house are to be backfilled by hand. One person can shovel about 24 cu. yds. Of earth per work day. How much earth can 2 people backfill in 2 days?
- Cu.yds
A kind of machine mix in concrete is called a/an?
Batch
How many feet before the construction work should the flagger be placed?
100 feet
When paving operations call for widths not common to normal paver widths:
Cutoff shoes or screed extensions may be used
In excavating a trench for a gravity flow sewer line, the elevation difference that provides the gradient which will help in carrying off the sewage is properly known as:
Fall
The finished thickness of the lime-treated material shall not vary more than ___ from the planned thickness at any point.
0.10 foot
What is the first thing that a driver should do when preparing to back up a piece of construction equipment?
Check back up alarm
A mix with incorrect coating or a stiff appearance of the larger aggregate particles signifies:
A cold mixture
Magazine buildings shall be located ___feet from low voltage electrical lines and ___ feet from high voltage electrical lines.
25 ; 100
All measurements are computed from a ___ grade stake offset. There is no difference in this respect between a vertical and rolled curb.
2 foot
What should the temperature be at the time of the first roll following the breakdown roll?
150˚ or more
Two types of straightedges are:
Rolling straightedge
Wood or metal straightedge laid on pavement
The operator can snake the scraper out by swinging the nose back and forth, if the mud is too deep or can?
Set the bowl down lifting the wheels
When mixing concrete, which ratio of water & cement indicates low-strength cement?
1 to 4
If it is hard to place, because there is too much filler in the mixture on should:
Increase placing temperature
How far apart must the upright braces be spaced when shoring a trench?
8 feet
If there is one lane in use for 2 directions of traffic, which of the following is necessary?
One flagman for each direction of traffic
What is the proper method of disposing of non-explosive caps?
Burn them
In shoring a trench, the pieces of lumber that run along each side of the trench longitudinally and are wedges against the sheathing or sheet piling to hold it in place are:
Whalers
If a pipe is buried in concrete, which has the best resistance to corrosion?
PVC
There is a smoother and quieter riding surface with aggregates smaller than ___ in diameter.
1/2”
Rapid curing cutbacks, due to the volatility of the solvent being extremely hazardous, may flash as low as:
80˚F
Internal stress or torque in a structural member which resists the lengthening effect of an externally applied force tending to increase the length of a member is known as:
Tensile strentgh
If a slurry seal is placed shortly before the overlay, cured and clean a tack coat:
May not be needed
A sprayed on application of asphalt to a wearing surface, with or without a thin layer of covering aggregate, is called an asphalt surface treatment, ___ or less in thickness.
1”
What is an area drain?
it is used to collect water from a particular area and put it into pipes that are underground
Spraying of untreated surface with a diluted slow-setting asphalt emulsion or a low-viscosity cutback is known as:
Dust laying
To what temperature should asphalt be heated before it is installed?
250˚ to 325˚
Some agencies require that pavement passes between joints be:
At the edge of the lanes
In figuring an estimate, drilling and blasting rock are taken off by its __ cubic yards quantity.
In-ground
The maximum mixing temperature of asphalt should never exceed:
177˚
The name of the scum on the top of the asphalt after it is rolled and set is:
Laitance
Natural gas has a heat value of ____ BTU’s per cubic foot.
1100
How many reflectorized rail faces does a Type II barricade have?
4
A swale is:
An invert on the ground
Leveling and dressing ground surfaces either by hand or machine conforming to pre-specified contours or elevations I preparation for a subsequent operation is known as:
Grading
If unstable material causes displacement, instead of aerating and drying the soil it is best to remove the unstable material and backfill with:
Asphalt aggregate mixture
Final compaction shall be completed approximately within ___ hours of final mixing.
36
A compression member whose unsupported length is ten or more times its least width is called a:
Column
How many feet over public walkways must service conductors be placed?
10 feet
Portable flashing beacons are mounted at a height of how many meters to the bottom of the lens?
3 meters
