Equipment Operator Advanced: Asphalt Plant Supervisor and Operations
What is the NCF ROA for a tack coat? • .10 • .15 • .20 • .25
.15
If the ROA is not known, what ROA is used in the NCF for planning purposes? • .1 • .2 • .3 • .4
.3
How many drums of tack coat material are required for a project 500 feet long and 50 feet wide with a waste factor of 5 percent and an ROA of .15? • 8.25 • 10.94 • 43.74 • 82.54
10.94
Which viscosity grade of MC ASPHALT bitumen is considered the most fluid? • 30 to 60 • 200 to 800 • 800 to 1,000 • 1,000 to 3,000
30 to 60
What is the spraying temperature of emulsion SS-1h? • 50°F-140°F • 75°F-130°F • 110°F-160°F • 135°F-175°F
75°F-130°F
The temperature of what element controls the temperature of an asphalt mix? • Asphalt • Dryer • Aggregates • Pugmill
Aggregates
Bin partitions should have which property to prevent intermingling of the aggregates within the hot bins? • Be tight fitting • Be free of holes • Be of sufficient height • All of the above
All of the above
Field identification of bituminous material found stockpiled in unmarked containers is necessary for which reason? • To determine the type and method of construction it can be used for • To establish safe handling practices for the material • To determine type and quality of equipment needed • All of the above
All of the above
What is the purpose of a prime coat? • To waterproof the surface • To plug capillary voids • To coat and BOND loose particles • All of the above
All of the above
What is/are the function(s) of the aggregates in an ASPHALT surface? • Transmits the load from the surface to the subgrade • Absorbs the abrasive wear of the traffic • Provides a nonskid surface • All of the above
All of the above
Which factor(s) control(s) the time required for aggregate to pass through a dryer? • Cylinder speed • Slope of the cylinder • Length, arrangements, and number of flights • All of the above
All of the above
What does a bituminous wearing surface Lack? • Flexibility • Bearing action • Versatility • Expedience
Bearing action
When should the aggregate in a drum-mix plant be proportioned? • As it enters the pugmill • After the cold-feed system • Before entering the mixing drum • Upon introduction with the bitumen
Before entering the mixing drum
If not kept clean, which component(s) can be a serious cause of air pollution at an asphalt plant? • DUST COLLECTOR • Burners • Storage silos • Batching unit
Burners
From the hot bins, what size aggregates are DEPOSITED into the weigh-hopper first? • Coarse • Intermediate • Fine • Mineral filler
Coarse
The proper amount of aggregates for ASPHALT mixes is initially controlled by a uniform flow of the aggregate through what component? • Cold-feed adjustment • Hot-feed adjustment • Cold-bin capacity • Hot-bin capacity
Cold-feed adjustment
What factor determines the amount of dust from the DUST COLLECTOR that can be returned to the plant? • Moisture content • Degree of suspension efficiency • Mix specification • Combined grading of the finish mix
Combined grading of the finish mix
When aggregate particles show signs of an oily coating after leaving the dryer, what adjustment should you make? • Decrease the amount of fuel oil • Decrease blower or draft air pressure • Increase the amount of fuel oil • Increase the amount of natural gas
Decrease the amount of fuel oil
In a drum-mix plant, in what location is aggregate mixed with the ASPHALT? • Mix surge silo • Hot-mix conveyer • DUST COLLECTOR • Dryer
Dryer
In a continuous-flow plant, a SAMPLE of hot aggregate should be obtained from which location? • Scalping screens • Overflow vents • Feeder gates • Dryer
Feeder gates
When used with asphalt cement, which distillate allows for SLOW curing after application to a roadway? • Naphtha • Kerosene • Fuel oil • Gasoline
Fuel oil
What grade of ASPHALT is indicated by a field test in which the sharp point of a pencil penetrates the asphalt with difficulty? • Hard • Medium • Medium hard • Soft
Hard
Exposure to what environmental condition(s) makes asphalt film harden on the aggregates? • Air only • Moisture only • Heat and Air • Moisture and air
Heat and Air
What function does the vertical slot in the ASPHALT return line serve in asphalt heating and circulation? • It breaks the vacuum in the line upon reversing the pump • It allows for circulation of asphalt through the feeding and storage system • It prevents oxidation of the asphalt • It provides a means of SAMPLING asphalt
It breaks the vacuum in the line upon reversing the pump
What condition creates an oily coating on the aggregate particles? • Unheated aggregate • Unbalanced distribution of ASPHALT • Lack of balance in the burner operation • SLOWNESS of the drum-mixer speed
Lack of balance in the burner operation
What are the two types of preliminary treatments used before a bituminous surface is placed? • Bituminous coat and ASPHALT COAT • Prime coat and tack coat • Aggregate coat and bituminous coat • In-place coat and imported coat
Prime coat and tack coat
The overloading of the screens with aggregate underscores a need for control of what factor? • Proper dryer control • Proper weigh-hopper calibration • Proper cold feeding • Proper gradation control
Proper cold feeding
On a batch plant, the size of a batch varies according to the capacity of what component? • Hopper • Dryer • Pugmill • Screens
Pugmill
The Jet-Pulse system is used in an asphalt plant as a method to produce what result? • Pulses of heat to keep aggregate hot • Suction pulses to control dust • Pulse of pressure within a filter bag to dislodge "dust cake" • Stream of hot asphalt onto aggregates
Pulse of pressure within a filter bag to dislodge "dust cake"
What road tar symbol designates a hot tar? • RT 1 • RT 2 • RT 5 • RT 9
RT 9
What type of asphalt cutback is composed of asphalt cement and gasoline? • Rapid-curing • Medium-curing • Slow-curing • Road oil
Rapid-curing
The grading of an individual cold aggregate is determined by taking what action? • Matching a SAMPLE of aggregate with a previous marked sample • Running a sieve analysis • Measuring the rate of aggregate to the fines • Noting the progressive thickness of the fines
Running a sieve analysis
Final metering of mineral filler to a mix is accomplished through what device? • Constant speed vane • Screw feeder • Weigh feeder • Gate feeder
Screw feeder
Normally, what field test is used to differentiate between unknown bituminous materials? • Heat-odor • Solubility • Water-mixing • Penetration
Solubility
Which factor is required to support the bearing action on a bituminous wearing surface? • Larger aggregates are placed in the mix design • Subgrade and base course have adequate thickness, strength, cohesion, and bearing capacity • Amount of asphalt in the mix is upgraded • Mix is given adequate curing time
Subgrade and base course have adequate thickness, strength, cohesion, and bearing capacity
When you are performing the solubility test, what material will form a stringy undissolved mass? • Asphalt • Asphalt cement • Emulsion • Tar
Tar
What factor must be known at all times in order to maintain constant ASPHALTproportioning? • Temperature of the aggregate • Output temperature of the dryer • Temperature of the hot bins • Temperature of the asphalt
Temperature of the asphalt
As part of an ASPHALT mix design, what is the purpose of the mineral filler? • To increase the weight of intermediate aggregate • To decrease the curing time of the ASPHALT mix • To increase the workability of the asphalt mix • To fill in the voids of the aggregates
To fill in the voids of the aggregates
What is one function of a bituminous binder? • To hold the aggregate together • To bind the tars to the surface • To bind the asphalt to the road surface • To help the surface water seep into the road base
To hold the aggregate together
What period of time begins when all the combined mineral aggregates are in the mixer and ends when the gate is open? • Total mixing time • Wet mixing time • Dry mixing time • Shortest mixing time
Total mixing time
When added to ASPHALT cement, which produce(s) an asphalt emulsion? • Water only • Soap only • Water and soap • Kerosene
Water and soap
What factor is the basis for determining the quantity of asphalt delivered into the drum? • Weight of the aggregate • Gradation of the aggregate • Drum-mix output requirement • Speed of the in-line belt feeder
Weight of the aggregate
What period of time starts with the asphalt application and ends with the opening of the discharge gates? • Total mixing time • Wet mixing time • Dry mixing time • Shortest mixing time
Wet mixing time
