Nevada A-16 Paving of Streets, Driveways and Parking Lots Contractor Examination

Under NAC 624, which work is within Nevada A-16 Paving of Streets, Driveways and Parking Lots scope?

• AApplication of asphalt to streets, driveways, parking lots, boat ramps, and airport landi…
• BPlacement of portland-cement concrete pavements and curb-and-gutter only
• CScarifying and recycling existing asphaltic mat as a standalone A-11 recycling operation…
• DInstallation of primary overhead electric transmission lines and transformers

A parking-lot subgrade is specified at 95 percent relative compaction. The laboratory maximum dry density is 125.0 lb/ft³. What minimum in-place dry density is required?

• A112.5 lb/ft³
• B118.8 lb/ft³
• C125.0 lb/ft³
• D131.6 lb/ft³

A nuclear-gauge wet density is 128.0 lb/ft³ at 8.0 percent moisture. What is the dry density?

• A108.8 lb/ft³
• B118.5 lb/ft³
• C120.0 lb/ft³
• D138.2 lb/ft³

Nevada agency earthwork specifications commonly treat a maximum testable compacted soil lift as about how thick unless the Engineer approves otherwise?

• A2 inches
• B12 inches
• C24 inches
• D36 inches

A cut 200 feet long, 16 feet wide, and 18 inches average depth contains how many cubic yards of excavation (bank measure, ignore swell)?

• A178 cubic yards
• B200 cubic yards
• C533 cubic yards
• D4,800 cubic yards

A fill needs 850 compacted cubic yards. The borrow shrinks 15 percent from bank to compacted condition. How many bank cubic yards must be excavated?

• A723 bank cubic yards
• B850 bank cubic yards
• C1,000 bank cubic yards
• D1,150 bank cubic yards

Which laboratory test is commonly used on Nevada roadway earthwork to establish maximum dry density and optimum moisture for relative compaction?

• AAASHTO T 180 (modified Proctor) or the Proctor method named in the contract
• BASTM C39 compressive strength of concrete cylinders
• CAASHTO T 209 theoretical maximum specific gravity of asphalt (Rice test)
• DASTM D6927 Marshall stability of asphalt briquettes

A field dry density of 114.0 lb/ft³ is measured on a soil whose modified Proctor maximum is 120.0 lb/ft³. What relative compaction was achieved?

• A90 percent
• B95 percent
• C98 percent
• D105 percent

Southern Nevada Uniform / NDOT-style Section 401 pavement language typically requires finished subgrade to be scarified and recompacted to a minimum of 95 percent for at least what depth?

• A2 inches
• B8 inches
• C24 inches
• D48 inches

Which statement about optimum moisture content (OMC) is correct for compacting fine-grained subgrade soils?

• ACompaction is most efficient near OMC because water lubricates particles so they can reac…
• BSoil must always be compacted bone-dry so the Proctor curve can be ignored
• CAdding water always reduces dry density, so soils should be placed as wet as possible
• DOMC is the moisture at which the soil first becomes a liquid (the liquid limit)

A sheepsfoot (tamping) roller is generally the most effective primary compactor for which material?

• AClean, open-graded crushed stone base
• BPlastic clay or silty-clay subgrade
• CHot-mix asphalt surface course
• DOpen-graded friction course that must not be kneaded

Proof rolling of a prepared subgrade is performed primarily to:

• AMeasure nuclear-gauge moisture to 0.1 percent
• BDetect soft, pumping, or unstable areas that a single density test may miss
• CReplace the need for any laboratory Proctor curve
• DDetermine the asphalt binder performance grade

A driveway subgrade is 80 feet long and 12 feet wide. Cross-slope is specified at 2 percent from the garage toward the street. What is the elevation drop from the high edge to the low edge?

• A0.16 feet (about 1.9 inches)
• B0.24 feet (about 2.9 inches)
• C2.00 feet
• D2.40 feet

Which native soil condition most often requires over-excavation, chemical treatment, or a geotextile/geomembrane under a Nevada parking-lot section?

• AClean, well-graded sandy gravel with a high R-value
• BAASHTO A-6 or A-7 clay with more than about 36 percent passing the No. 200 sieve and a pl…
• CCrushed Type II aggregate base meeting the specified gradation
• DOpen-graded drain rock used only in a French drain

A 6-inch compacted aggregate-base lift is placed over 10,000 square feet. Ignoring waste, how many compacted cubic yards of base are required?

• A185 cubic yards
• B222 cubic yards
• C556 cubic yards
• D5,000 cubic yards

When natural ground will support less than about 5 feet of new embankment, Nevada agency Section 203 language commonly requires the top 8 inches of that ground, and the embankment itself, to be compacted to not less than:

• A70 percent relative compaction
• B90 percent relative compaction unless otherwise specified
• C100 percent of oven-dry density with no moisture control
• D50 percent of the liquid limit

A nuclear density gauge used on soil or aggregate (AASHTO T 310 / ASTM D6938) must be:

• AUsed without calibration because the reading is an absolute density
• BStandardized on reference blocks and correlated to the project materials as required by t…
• CFilled with diesel fuel each morning
• DUsed only on freshly placed hot-mix asphalt above 300°F

Which grading practice best prevents ponding on a paved parking lot?

• AA dead-level finished grade with no designed slope to inlets
• BA continuous minimum slope, commonly about 1 to 2 percent, draining to inlets or the stre…
• CA reverse slope that drains toward the building foundation
• DLeaving the subgrade 4 inches high and expecting the asphalt to flatten it

Blue-top or red-top grading stakes are used primarily to:

• AMark underground electric lines in APWA red
• BControl finished subgrade or base elevation and cross-slope
• CIndicate the asphalt plant mix temperature
• DReplace the need for a project survey benchmark

A cut of 1,200 bank cubic yards swells 25 percent when excavated. How many loose cubic yards must be hauled?

• A900 loose cubic yards
• B1,200 loose cubic yards
• C1,500 loose cubic yards
• D1,600 loose cubic yards

Which statement about benching a fill into an existing slope is correct?

• ANew fill may be dumped against a steep existing slope without keys or benches
• BThe existing slope should be benched so new fill is placed in horizontal lifts keyed into…
• CBenches are used only for landscaping and have no compaction purpose
• DVertical joints between old and new fill are preferred because they are easier to compact

A contractor must place 2,400 compacted cubic yards of Type II aggregate base. Trucks haul 15 loose cubic yards each, and the material shrinks 20 percent from loose to compacted. How many truckloads are required (ignore waste)?

• A128 truckloads
• B160 truckloads
• C192 truckloads
• D200 truckloads

Which statement best describes a crown on a two-lane street?

• AA high point near the centerline that slopes down toward each gutter or shoulder for drai…
• BA constant 8 percent cross-slope in one direction only
• CA depressed centerline that ponds water in the travel lanes
• DA vertical curve used only on airport taxiways

Unsuitable material encountered in a street or parking-lot subgrade should be:

• ACovered immediately with hot-mix asphalt to seal it in
• BRemoved to the depth directed by the Engineer or geotechnical report and replaced with ap…
• CFlooded overnight so it will compact more easily the next day
• DLeft in place if it is only in the wheel paths

A 300-foot by 150-foot parking lot must be raised 4 inches with compacted fill. Ignoring waste and shrinkage, how many compacted cubic yards are required?

• A556 cubic yards
• B1,667 cubic yards
• C4,500 cubic yards
• D15,000 cubic yards

Which condition most often prevents a fine-grained subgrade from reaching specified density even after many roller passes?

• AMoisture well above optimum, so the soil pumps and weaves under the roller
• BUse of a sheepsfoot roller on clay
• CPlacing the soil in 8-inch lifts
• DProof rolling after density tests pass

A residential street section is specified as 4 inches Type II aggregate base over compacted subgrade. After placing and compacting the base, the finished surface is 0.08 feet low. How much additional compacted base is needed, in inches?

• A0.10 inch
• B0.50 inch
• C0.96 inch
• D8.00 inches

Which statement about R-value testing of subgrade soils is most accurate for Nevada pavement design?

• AA higher R-value indicates a stronger, more resistant subgrade that can support a thinner…
• BR-value is the same measurement as asphalt Rice specific gravity
• CAn R-value of zero is required for all parking lots
• DR-value replaces the need for compaction testing of the finished subgrade

Haul roads and construction traffic on a finished subgrade or aggregate base should be controlled because:

• AWheel loads can loosen, rut, and contaminate a surface that already met density
• BConstruction traffic always improves density so no restriction is needed
• CSubgrade density increases automatically after 24 hours of air drying
• DAsphalt tack coat will repair any rutting in the base

A trench through a future asphalt driveway is backfilled with native soil in one 4-foot lift and wheel-rolled once. What is the most likely pavement result?

• AA long-lasting, uniform driveway because one thick lift is more stable
• BSettlement and a reflective dip or crack over the trench after paving
• CHigher density than thin lifts because the backhoe bucket provides extra energy
• DNo effect, because asphalt bridges any backfill void

What is the primary purpose of a tack coat in hot-mix asphalt paving?

• ATo waterproof and bind an untreated granular base (a prime-coat function)
• BTo create a bond between pavement layers so they act as one structural unit
• CTo cool the mix before breakdown rolling
• DTo replace the need for compaction of the new mat

A 3-inch compacted HMA surface is specified for a 300-foot by 150-foot parking lot. Using 145 lb/ft³ compacted density, how many tons are required (ignore waste)?

• A408 tons
• B816 tons
• C1,088 tons
• D1,631 tons

Using 110 lb per square yard per inch of compacted thickness, how many tons of dense-graded HMA are needed for a 24-foot-wide by 500-foot-long lane at 2 inches compacted thickness? Ignore waste.

• A73 tons
• B110 tons
• C147 tons
• D220 tons

A Nevada agency plantmix specification lists these minimum base (surface) temperatures: 40°F for mats 3 inches or greater, 45°F for mats greater than 1 inch but less than 3 inches, and 50°F for mats 1 inch or less. A 1.5-inch overlay is planned. What is the minimum underlying surface temperature for placement?

• A32°F
• B40°F
• C45°F
• D60°F

Which roller is typically used first, immediately behind the paver, for breakdown compaction of dense-graded HMA?

• AA static sheepsfoot roller
• BA steel-wheel (often vibratory) breakdown roller while the mat is still hot
• CA water truck used as a roller
• DA grid roller intended for rock fill

A pneumatic-tired (rubber-tire) roller is used in the intermediate position primarily to:

• AKnead the mat, seal surface voids, and improve density without leaving a steel-wheel text…
• BReplace the need for any steel-wheel rolling
• CCool the mat rapidly with water spray so traffic can enter in 5 minutes
• DPrime an unbound aggregate base

On a superelevated curve, rolling of a hot-mix lift should generally begin:

• AAt the high (upper) edge and work downhill
• BAt the low side and work toward the high side
• COnly in the exact center of the lane
• DDiagonally across the crown at 45 degrees

A cold longitudinal joint should be prepared by:

• ALeaving the cold edge ragged and dry so the new mix will key into it
• BCutting or milling a vertical face as required and applying tack to the cold edge before…
• CPainting the joint with white 811 paint
• DWetting the joint with diesel fuel to keep the rake from sticking

Which practice best reduces thermal and gradation segregation between the truck and the paver?

• ADumping each truck in a single pile on the grade and blading it into the hopper
• BUsing a material transfer vehicle (MTV) or remixing hopper so the paver is fed a uniform,…
• CLetting the mix sit in the truck until it crusts, then loading the paver
• DTurning off the hopper slat conveyors so the mix can cool in the hopper wings

A truck-bed release agent for HMA should be:

• ADiesel fuel, because it is inexpensive and always permitted
• BAn approved non-petroleum or specified release agent applied sparingly so it does not con…
• CUsed motor oil from the paver engine
• DA heavy coat of tack emulsion in the bed

Haul trucks delivering HMA should have tarps or covers primarily to:

• AHide the load from the inspector
• BProtect the mix from rain, wind cooling, and crusting during the haul
• CIncrease the legal axle weight of the truck
• DEliminate the need for a truck scale ticket

If a load of HMA arrives at the paver well below the specified placement-temperature range, the contractor should:

• APlace it anyway and add extra water to the roller drums
• BReject or set aside the load; cool mix cannot be compacted to specified density
• CBlend it 50/50 with a hotter load in the hopper wings
• DUse it only on the longitudinal joint where density is less important

A paver screed should be:

• AAllowed to run empty of mix so it can cool between trucks
• BKept uniformly full, heated, and moving so the mat thickness and texture stay consistent
• CRaised off the mat whenever a truck hooks up
• DUsed only for prime-coat application

Which statement about longitudinal joint location on a street overlay is best practice?

• AOffset the new joint from the underlying joint and keep it out of the wheel path when pra…
• BStack every new joint directly over the old joint in the wheel path
• CPlace the joint down the exact center of each travel lane
• DEliminate joints by paving 40-foot-wide streets in one 8-foot pass

A transverse construction joint at the end of a paving day is best made by:

• ALeaving a feathered wedge and rolling it until it disappears
• BPlacing a bulkhead or saw-cutting back to full thickness and tacking the vertical face be…
• CRaking diesel into the cold end
• DCovering the ragged end with loose millings overnight

Field density of compacted HMA is commonly expressed as a percent of:

• AThe soil modified-Proctor maximum dry density
• BThe theoretical maximum specific gravity of the mixture (Gmm, Rice gravity)
• CThe liquid limit of the binder
• DThe truck-ticket wet weight divided by 27