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SECTION 401 – PLANTMIX BITUMINOUS PAVEMENTS – GENERAL

Durango Drive 401 - 1 Project No. L-1992 Blue Diamond Road to Windmill Lane Addendum 4

SECTION 401

PLANTMIX BITUMINOUS PAVEMENTS – GENERAL

DESCRIPTION

401.01.01 GENERAL

The following is added to this subsection: D. This project includes a roadway maintained by the Nevada Department of Transportation

and is subject to the Standard Drawings and Specifications developed by that public agency. Information regarding the requirements of NDOT is available on the Internet at https://www.nevadadot.com/doing-business/contractors-construction/contract-services/standard-specifications-and-plans

Roadway in this project that will be subject to NDOT guidelines is Blue Diamond Road.

MATERIALS

401.02.01 COMPOSITION OF MIXTURES

Revise Paragraph “A” as follows:

A. The bituminous plantmix shall be composed of a mixture of aggregate, mineral filler if required, and bituminous material. The aggregate fractions shall be sized, uniformly graded, and combined in such proportions that the resulting mixture meets the grading requirements of the job-mix formula. Mineral filler shall be added by the marinating method as per 401.03.08.F2 Marination Method.

At the time of daily production, two (2) full quart samples of the asphalt cement shall be submitted to the Clark County Public Works laboratory. The samples will be fingerprinted using a Fourier Transform InfraRed Spectrometer (FTIR) for future binder comparison. All subsequent binder samples will be analyzed and compared with the fingerprint of the FTIR reference samples. If the fingerprint of any subsequent binder sample does not match the reference fingerprint, the paving shall be halted until the Contractor can verify the proper binder.

Revise Paragraph “B” as follows:

B. Before starting work, the Contractor shall submit a proposed job-mix formula in writing.

1. The proposed job-mix formula shall be determined by a testing laboratory under the direction and control of a registered professional engineer, based on tests performed in accordance with the "Marshall Method of Mix Design" as described in the Asphalt Institute Manual Series No. 2 (MS-2), latest edition and in accordance with additional requirements as listed in these special provisions.

SECTION 401 – PLANTMIX BITUMINOUS PAVEMENTS - GENERAL


2. In AASHTO T340, replace AASHTO T166 with AASHTO T331 “Standard Method of Test for Bulk Specific Gravity (GMB) and Density of Compacted Hot Mix Asphalt (HMA) Using Automatic Vacuum Sealing Method” for air void determination.

3. The maximum and nominal aggregate size is based upon the FHWA definition.

4. Comply with the pre-compacted two-hour mix cure requirements of MS-2.

5. The use of a posted IQAC material shall be verified with the contract specification, and two (2) check points shall be provided to verify the mix design compliance.

Revise Paragraph “C” as follows:

C. The job mix formula shall be based on 4 percent air voids. For the Type 2C designs, a test strip shall be used to verify the design properties.

1. The job-mix formula aggregate with the allowable tolerances herein shall conform to the requirements of Section 705 "Aggregates for Bituminous Courses," for plantmix bituminous aggregates

2. A stamped original of the mix design and check point reports shall be uploaded into Submittal Exchange.

3. Type 2C mix designs shall be rut tested with the Asphalt Pavement Analyzer (APA) per AASHTO T340.

a. Once the target mix design is selected for a Type 2C, three rut test beams or six cylinder samples shall be fabricated by the Contractor. Each cylinder sample shall be 6-inch in diameter. The rut test beam samples shall be compacted using the PTI vibratory compactor to an air void content of 7% +/- 1.0%. The rut test cylinder samples shall be compacted to an air void content of 7% +/- 1.0%.

b. The specimens may be fabricated using the vibratory or Marshall Hammer. The molds must match the outside diameter the samples. No modification of the samples will be permitted.

4. The samples shall be tested in the PTI Asphalt Pavement Analyzer (APA) in air at 76 degrees C for 20,000 rut cycles. Should the target design fail to meet the specified rut test requirements in Table 1, the Contractor shall modify the gradation within the design limits, redesign, and retest.

Revise Paragraph “D” as follows:

D. The job-mix formula asphalt content shall satisfy all Marshall Design criteria as required in the most current Asphalt Institute MS-2, the contract, and as shown in the following table

Table 1 Design Criteria



Asphalt Concrete

COLLECTORS & ARTERIAL

RESIDENTIAL Trails,

Medians, Sidewalks

R/W width 60 ft. or greater

Under 60 ft. N/A

Traffic Category1 I II N/A Gradation Type 2C 2F or 3 3 Maximum Size (Superpave)

1” 1” or ½” ½”

Nominal Maximum Size (Superpave)

¾” ½” or #4” #4”

Asphalt cement Type PG76-22NV PG76-22NV PG64-22

or PG70-16

Compaction Blows Each End of Specimen

75 50 50

Test Property Min. Max Min. Max. Min. Max.

Percent Total Air Voids2 3 5 3 5 3 5 Flow 8 14 8 16 8 16 Stability 1800 -- 1200 -- 1200 -- VMA3 12 -- 14 -- 14 -- VFA 65 78 65 75 65 75 Film Thickness 7 7 7 Indirect Tensile Strength (Unconditioned) AASHTO T283

100 psi min

Indirect Tensile Strength (Retained Strength) AASHTO T 283

75 % minimum

APA rut test @ 76oF @ 8000 cycles, mm

1 2.5 --- --- --- ---

APA rut test @ 76oF @ 20,000 cycles, mm

1 4 --- --- --- ---

APA rut test @ 76oF maximum slope between 8000 cycles to 20,000

-- 0.2 / 1000

--- --- --- ---

Dust to Binder Ratio 0.8 1.6 0.9 2.0 0.9 2.0

Delete Paragraph “E”

1 See roadway classification in Subsection 401.01.02 2 The asphalt cement to be adjusted during the test strip as approved by the Engineer. 3 May be adjusted by the contractor with approval of the Engineer to obtain passing values of the mix design

and compaction requirements.



Revise Paragraph “F” as follows:

F. If the addition of mineral filler fails to achieve the minimum tensile strengths, the Contractor shall be required to change sources of material, and submit a new job-mix formula that will satisfy all design criteria.

Revise Paragraph “G” as follows:

G. The test report shall show the curves and data tabulations used to determine the mix design characteristics. CCPW form D-401 shall be used for the mix design submittal. The form can be found at the following web site:

http://pwgate.co.clark.nv.us/IQAC/qaqc.asp

Delete Paragraph “H”.

Delete Paragraph “I”.

Delete Paragraph “J”.

Revise Paragraph “K” as follows:

K. The job-mix formula aggregate with the allowable tolerances herein shall conform to Section 705, “Aggregate for Bituminous Courses,” for plantmix bituminous base aggregates and plantmix bituminous surface aggregates as applicable.

Revise Paragraph “L” as follows:

L. The Contractor shall determine a job-mix formula, and submit to the Engineer through submittal exchange. This job-mix formula shall only be modified with the written approval of the Engineer. The mix furnished shall conform to this job-mix formula, within the following range of tolerances:

1. Aggregate passing the No. 4 and larger sieves: ±7 percent

2. Aggregate passing the No. 8 to No. 100 sieves: ±4 percent

3. Aggregate passing the No. 200 sieve: ± 2 percent, but not to exceed upper limit of specification. Mineral filler is not considered as part of the aggregate.

4. Bitumen content: ±0.3 percent

5. Temperature leaving the mixer: ± 20 degrees F

6. Temperature in hopper of paving machine: ± 20 degrees F

7. The job-mix formula shall reflect the asphalt percentage recommended by the approved mix design. Consistently produce a mixture with asphalt content at the target value. Do not use the above operational tolerance as a means to alter the asphalt content target value.



Revise Paragraph “M” as follows:

M. Should there be a change in sources of materials, a new job-mix formula shall be established before the new material is used. Check tests of properties of the plantmix bituminous materials shall be made on the first day of production and as requested by the Engineer during period of construction to confirm that all properties are in compliance with Marshall Design Criteria and tensile strength requirements. Adjustments in gradation, mineral filler content and asphalt content shall be made as necessary in order to meet design criteria. A new mix design and job-mix formula shall be established before the material is used.

The test results shall be submitted to the Engineer through Submittal Exchange. With approval of the Engineer, adjustments in gradation, mineral filler content, and asphalt content shall be made as necessary to meet the design criteria.

Revise Paragraph “N” as follows:

N. The temperature of the bituminous material just prior to mixing and of the completed mixture in the hauling vehicle just prior to leaving the plant shall conform to the following table:

Table 2 Plantmix Bituminous Mixture with Asphalt Cement

Grade of Mixture at Paver Mixture at the Plant

Asphalt Cement Minimum Maximum

PG64-22; PG70-16, or AC-30

270ºF 330ºF

PG76-22NV 300ºF 350ºF

401.02.04 BITUMINOUS MATERIALS


B. Unless otherwise specified in the Special Provisions for Category I pavements, the grade of bituminous material for dense graded mixes shall be as specified on Table 1.

Revise Paragraph “C” as follows.

C. Unless otherwise specified in the Special Provisions, for Category II pavements the grade of bituminous material for dense-graded mixes shall be as specified on Table 1.

Revise Paragraph “D” as follows.

D. A certification shall be submitted for each asphalt cement shipment that represents the batch lot.



401.02.05 FIELD COMPACTION AND MIX DESIGN CORRELATION


A. The mix test strip is to be used only for the Type 2C designs for a project greater than 1000 tons. On the first day of bituminous mix production, produce between 500 and 1000 tons of mix. Complete the placement of the mix test strip in the same shift. Produce the mixtures at the medium speed used during the plant calibration.

A test strip is required to determine the final bitumen content based on the compaction point of refusal. A test strip report summarizing all the results and the recommended bitumen content shall be submitted. The report shall be stamped by a licensed Nevada professional engineer. At any time, if there are any changes in the sources or paving operations, then a new test strip is required. Previous test strip results from Clark County Public Works projects can be accepted if those test strip results were reviewed and accepted as long as the test strip was within the previous six months, if approved by the Engineer. When possible, the test strip may be placed on the shoulder of the roadway or the passing lane of four-lane roadways and become a section of the completed roadway.

For other roadways, place at a location approved by the Engineer.

Test strip procedure for Category 1 roads:

1. For production of the bituminous material, the production plant is set to the design mix formula.

2. Compaction of materials shall be tested during break down roller and finish roller phases. At each phase, the compaction continues until the subsequent values on the compaction gauge do not increase by more than 0.2 percent. If there is a plant asphalt content bias, it shall be stated in the test strip data.

3. The field compaction shall be as required in Section 401.03.11 “Rolling and Compaction”.

4. The in-place air voids shall be based on the Maximum Theoretical Specific Gravity using AASHTO T209 and seven (7) core densities using Nev T335. These are to be taken from seven (7) sub-lots from the day’s placement.

5. A graph is plotted for each roller pattern with the x-axis representing passes and the y-axis representing density. A pass is defined as rolling over the compaction test location two times. The graphs, with test data, shall be submitted, attached to the initial design to the Engineer with the original and corrected binder content noted.

6. If it has been determined that the average compaction is more than 95% or less than 93%, the bitumen content shall be mathematically increased or reduced and noted on the mix design submittal and approved by the engineer. A set of check points must be tested for the percent laboratory air voids. If adjustment is made, then a new test strip is required or, if approved by the Engineer, may proceed

7. This procedure will be required as a part of all new mix designs and each project. The graphs, with test data, shall be submitted, attached to the initial design to the Engineer with the original and corrected binder content noted



8. As a part of the Quality Control, the mix design shall be rut tested using random samples from the test strip for 1 set per design of six (6) 6-inch cores. All test strips will require rut testing. A map of core locations shall be included with the test information. It shall indicate the locations by offset from the centerline and project stationing. A set of cores shall be delivered to the Clark County Public Works Construction Management laboratory for correlation testing. The test results shall be submitted within 3 calendar days.

9. The cores must be taken and patched prior to opening to the traffic.

10. If the compaction cannot be maintained between the above limits, a new test strip shall be implemented to re-establish the mean density for testing.

Subsequent compaction testing lots shall be tested in accordance to Section 401.03.12 “Acceptance Sampling and Testing of Bituminous Mixture” of the special provisions.

At no time shall the project compaction effort be stopped prior to the rolling pattern break point. If during the paving operation the rolling pattern break point increases the compaction beyond the compaction parameters, the paving operation must stop.

At the same time as core extractions for ruts, nuclear density test the core locations for daily nuclear gauge correlation verification per section 401.03.12 (D)

Delete Paragraph “B.”

Revise Paragraph “C.1 as follows:

C. The field compaction shall be as required in Section 401.03.11, "Rolling and Compaction."

1. The in-place air voids (compaction) shall be based on the Maximum Theoretical Specific Gravity and unit weight of rut core samples taken during test strip placement.

The following subsections are added to this Section:

401.02.06 (NDOT) PLANTMIX BITUMINOUS PAVEMENT This project includes a roadway maintained by the Nevada Department of Transportation and is subject to the Standard Drawings and Specifications developed by that public agency. Information regarding the requirements of NDOT is available on the Internet at https://www.nevadadot.com/doing-business/contractors-construction/contract-services/standard-specifications-and-plans Roadway in this project that will be subject to NDOT guidelines is Blue Diamond Road. The following revisions apply to the Nevada Department of Transportation’s 2014 Standard Specifications for Road and Bridge Construction (Silver Book). (NDOT) 401.02.02 Composition of Mixtures. Asphalt Cement, Grade PG 76-22NV shall be the only grade permitted for use in plantmix bituminous dense-graded and open-graded aggregate mixtures.



The Department reserves the right to change the grade of the asphalt by one grade at no additional cost to the contract. The grade of asphalt to be used in the dense-graded bituminous mixtures will be determined by the Department based on a mix design using aggregates produced for the project. Once the determination of the grade and source of asphalt has been made, do not make changes unless new samples are submitted and a new design mix is approved.

CONSTRUCTION

401.03.01 BITUMINOUS MIXING PLANT

Add the following to Paragraph “C”:

7. Baghouse Fines. If introducing baghouse fines into the mix, draw the material from a storage facility in which the material is kept in a uniform free flowing condition. Supply the baghouse fines for delivery to the plant from a positive weighing device which is interlocked, (rate of baghouse fines introduction shall automatically vary with the rate of the aggregate feeder) to the flow of each aggregate feeder. Equip the baghouse feeder to provide continuous uniform flow within 5% of the actual mass.

8. Calibrate the baghouse fines feeder at two different speeds (lowest and highest speed of anticipated operation) in relation to the speed of the aggregate feed. Provide an approved calibrated scale or weigh metering device to determining the actual mass of the baghouse fines for each test. Furnish a test box having a sufficient capacity to perform the calibration testing. Calibrate the baghouse fines feed so the masses shown on the metering device are within +- 5% of the weighed mass.

9. Add the baghouse fines at the asphalt feed line to insure a uniform mix. Introduce the baghouse fines at an approved point, at a percentage determined by the Department’s Materials Division, and not exceeding 2% by dry mass of the aggregate. Consider baghouse fines as part of the aggregate, and not as a mineral filler.

10. Controls. Do not operate mixing plants with manual controls

Delete Paragraph “D”

Revise Paragraph “E.3” as follows:

3. The Contractor must submit to the engineer the Weight Calibration of Aggregate on an annual basis.

a. Calibrate the aggregate weigh belt at 3 different speeds, (lowest, medium, and the highest speed of anticipated operation) using the bin percentages from the approved mix design with the assigned material in the bins.

b. Provide accurate platform scales in the same pit as the plant, and test boxes having a capacity of not less than 10 tons for this purpose.

c. Calibrate the aggregate feed so the masses shown on the console indicators are within 1% of the actual mass as weighed on the sealed platform scales. The difference of the 3 runs will be within 1% of each other. During production do not run outside the parameters of the plant calibration masses.



d. Supply a graph of each individual bin showing the speed of the belt to the tons per hour of the material. The graph will be checked during the calibration and must be approved before production proceeds.

Revise Paragraph “E.4” to read as follows:

4. Bituminous Metering Device:

a. Introduce the bituminous material into the mixer through a positive displacement metering device.

b. Equip this metering device with a ready means of varying the bituminous delivery rate.

c. Before beginning the plantmix operation, and at any other time directed, calibrate the bitumen feed at 3 different speeds (lowest, medium, and the highest speed of anticipated operation) in relation to the aggregate feed using the bitumen ratio se t forth in the approved mix design so the gallons shown on the indicators are within 0.5% of the actual gallons as weighed on the certified platform scales.

d. Use a vessel for calibration having a capacity of not less than 1,000 gal.

e. This calibration procedure will be observed and must be approved.

f. If the supplier has calibration document from NDOT dated within three months of the project, the calibration procedure may be waived.

401.03.02 HAULING EQUIPMENT

Add the following to Paragraph “A:”

The use of diesel fuel shall not be allowed as a release agent.

401.03.03 PAVERS

Revise Paragraph “E” as follows:

E. The screed shall be equipped with automatic controls which will make adjustments in both transverse and longitudinal direction. The external longitudinal reference devices used to pick up grade information for the automatic sensing control shall conform to the following:

1. When picking up grade information from an underlying base, the external longitudinal reference device shall be a floating beam at least 30 feet long or a 27-foot non-contact averaging ski with a minimum of 4 sensors.

2. When picking up grade information from an adjacent compacted pavement course or a concrete surface, the external longitudinal reference device shall be a floating beam or a non-contact averaging ski with a minimum of 2 sensors. Either referencing device shall be at least 10 feet in length.



3. When using a floating beam to pick up grade information, place the sensing device in the middle third of the floating beam.

4. A non-contact sensor shall not be allowed to pick up grade information from a newly placed adjacent compacted course.

5. Should the automatic controls fail to function properly, finishing the half shift with manual controls may be approved. Do not resume until the controls are repaired.

6. The material shall be placed without segregation.

401.03.05 WEATHER LIMITATIONS


A. The bituminous mixture shall not be placed upon any wet surface, when frozen materials are present in the base, or when the surface temperatures of the underlying course is less than specified in Table 1. Do not place plantmix bituminous surface during rain or snowfall.

TABLE 1 - BASE TEMPERATURE LIMITATIONS

Mat Thickness Base Temperature

(Minimum ºF)

3 Inches or Greater 40

Greater than 1 Inch but Less than 3 Inches 45

1 Inch or Less 50

401.03.06 PREPARATION OF EXISTING SURFACE


C. If the plantmix bituminous surface is being constructed directly upon an existing hard surfaced pavement, a tack coat shall be applied as per section 405 “Tack Coat”.

1. The surface shall be free of water, foreign material, or dust when the tack coat is applied.

2. To minimize public inconvenience, no greater area shall be treated in any one day than is planned to be covered by plantmix during the same day.

401.03.07 PREPARATION OF BITUMINOUS MATERIALS

Add the following to Paragraph “A”:

When polymer modified bituminous asphalt is placed in storage tanks, continuously circulate or moderately agitate them within the tanks.

401.03.08 PREPARATION OF AGGREGATES

Add the following to Paragraph “A:”

3. When the required tonnage is more than 5,000 tons, maintain a minimum of 5,000 tons of material proportionately stockpiled until such time as 5,000 tons or less are needed to complete the plantmix operations.



4. Place the aggregates in the cold feed proportioning bins directly from the stockpile.

5. Do not charge the cold feed bins from the crushing plant.

6. Prior to the use of the aggregate stockpiles, the Contractor shall sample, test, and certify that the piles meet the aggregate requirements in Subsection 705.03.01, “Plantmix and Roadmix Bituminous Base and Surface Aggregate.

7. The cost of furnishing asphalt or aggregate samples to the Engineer will not be paid for directly but shall be considered included in the contract unit price bid for other items of work.

Delete Paragraph “F1.”

Add the following to Paragraph “F2”:

f. Fine aggregate stockpiles have a minimum of 50% passing the No. 4 sieve.

g. All other stockpiles will be treated as coarse aggregate.

h. Marinate stockpiles individually. Do not use the marinating method process to combine the stockpiles.

i. Correct the plasticity problem if the plasticity index of any individual stockpile exceeds 10 before marinating the material. Do not blend with sand to lower the plasticity index

Delete Paragraph “F3”:

401.03.09 MIXING Revise the first sentence in Paragraph A to read as follows:

A. The permissible moisture content of the bituminous mixture just behind the paver shall not exceed 1 percent as determined by test method Nev. T112 (Method A) or Nev. T306. If the test result exceeds 1 percent, the material production shall cease.

401.03.10 SPREADING AND FINISHING

The following is added to this subsection.

G. The Contractor shall use equipment to eliminate segregation. A Material Transfer Vehicle (MTV) for conveyance of mixture from the hauling truck or roadway to the paving machine shall be used, unless within residential subdivision or for a daily production of category I mix less than 2500 SF.

401.03.11 ROLLING AND COMPACTION

Add the following to Paragraph “B”



3. Joint edge compaction equipment may be used in order to increase the compaction of the joint

4. Visual segregation of the mix that occurs during placement shall be removed prior to compaction. The placement shall not proceed until the cause is remedied.

Add the following to Paragraph “C”

1. Perform all compaction rolling, defined as breakdown, while the internal temperature of the mid-depth of the mat is above 290 degrees F.

2. The use of intelligent compaction techniques is permitted. The contractor shall incorporate training of the Engineer or the representatives.

3. The final rolling of the bituminous mixture shall be performed with the same type of roller used for breakdown rolling. Vibration shall not be used.

4. Complete finish rolling within the same day of placement of the plantmix bituminous surface while the internal temperature of the mat at mid-depth is as follows:

a. Above 150 degrees F for all asphalt cements except over 15% tire rubber

b. Above 180 degrees F for 15% or greater tire rubber asphalt cement 5. Under no circumstances, shall the contractor compact the pavement to increase the

compaction density when the internal temperature is less than 150 degrees F or after the day of paving.

6. Place each course of the plantmix bituminous surface for a minimum of a full lane width.

7. Any portion of the course may be advanced only to the extent of one day’s operation before beginning work on a succeeding width.

8. Complete the course to its full plan width before any general longitudinal advancement beyond the width first placed.

9. Unless otherwise ordered, bring all portions of the course to as near the same point as practicable before suspending paving operations for more than one day.

10. Minimum lift thickness for Category I design is 2-1/2 inches. If approved by the Engineer a two (2) inches lift may be permitted if after as determined by the Engineer, the placement indicates a “visual” segregation, the Contractor shall, if the pavement design thickness permits, to use a 2-1/2 minimum lift. The maximum lift thickness is four (4) inches.

Revise Paragraph “E” as follows

E. To prevent adhesion of the mixture to the roller, the wheels shall be kept properly maintained. Use a minimum amount of one of the asphalt release agents listed in the NDOT



Qualified Products List (QPL) to prevent the mixture from adhering. The use of diesel oil on any rollers is prohibited.

401.03.12 ACCEPTANCE SAMPLING AND TESTING OF BITUMINOUS MIXTURE

Revise Paragraph “A1” as follows:

1 A lot shall be divided into sub-lots of a maximum of 5000 square feet in area, for a minimum of 3 sub-lots per lot, and at least one random test shall be taken in each sub-lot.


C. Determination of the field density of the compacted bituminous mixture shall be accomplished by either of the methods listed below. In case of dispute, AASHTO T331 as modified shall govern.

1 NDOT T335 “Method of Test for Relative Compaction of Plantmix Bituminous Base and Surface Using a Nuclear Density Gauge”

2 ASTM D1188, “Bulk Specific Gravity of Compacted Bituminous Mixtures Using Paraffin-Coated Specimens.” When this method is used, the procedure shall be modified to require the use of “Coated Specimens” (Para-film only). The use of Bulk Specific Gravity determinations by SSD (surface saturated dry) method is prohibited. Zinc stearate shall NOT be substituted for paraffin.

3 AASHTO T 331, Bulk Specific Gravity and Density of Compacted Asphalt Mixtures Using Automatic Vacuum Sealing Method.

Revise Paragraph “D” as follows:

D. Use the procedure NDOT T335 “Method of Test for Relative Compaction of Plantmix Bituminous Base and Surface Using a Nuclear Density Gauge” for calibration of the nuclear gauge.

1. A minimum of 1 lot (one full day’s production), and not less than 7 sub-lots, shall be used for this correlation.

2. Should any nuclear test density in the first lot differ from its corresponding drilled core density by more than 3.00 percent relative compaction, a second lot shall be correlated and the average of all sub-lots in the first and second lots, shall be used for the correlation. The 4 inch cores shall be transferred to the Engineer along with the random number generator listing station/offset locations.

3. Nuclear Gauges used to determine field densities shall be correlated on the Test Strip with drilled cores per NDOT T335 with the following requirement. The nuclear gauge correlation shall be verified each day against the minimum of the average of two cores. The RUT cores for each day’s placement may be used as the correlation cores.

a. The Correction Factor must be between the range of 0.97 to 1.03



b. If the Nuclear Gauge fails to meet this tolerance, the gauge will not be allowed to be used on plantmix bituminous base.

4. The calibration is required for each mix design.

Revise Paragraph “F” as follows:

F. The frequency of testing by the contractor shall be in accordance to the Table 1 located on the website:

http://pwgate.co.clark.nv.us/IQAC/qaqc.asp

The testing performed by the Contractor may be used by the Engineer in part or in whole as the basis of acceptance in addition to the Quality Assurance testing that is done by the Engineer.

Revise Paragraph “G” as follows:

G. The pavement thickness acceptance criteria are as listed below:

1. If the median of all measurements meets or exceeds the design thickness, the placement is acceptable. If the median thickness is less than the required thickness, the bid item reduction formula shall be used is as follows:

Two (2) Inch Pavement Thickness Bid Item Reduction

200 300100

x=Actual pavement thickness

y=Bid item revised for the reduced life. Round to the nearest tenth.

If the median is less than 90% of design thickness, the deficient pavement limits shall be identified, removed and replaced.

Three (3) Inch Pavement Thickness Bid Item Reduction

133 299100

x=Remaining pavement thickness





Four (4) Inch Pavement Thickness Bid Item Reduction

103 312100




Five (5) Inch Pavement Thickness Bid Item Reduction

80 300100




Six (6) Inch Pavement Thickness Bid Item Reduction

52 212100






2. If there is only an isolated thin area, the limits of the area should be identified to determine if a construction resolution is necessary.

Revise Paragraph H as follows:

H. The pavement density acceptance criteria for production placements shall be as listed below, or as otherwise specified in the project plans or contract documents:

Density Acceptance

1. All median or average values shall be calculated to the nearest three significant figures.

2. Unless otherwise specified in the project Drawings or contract documents, each lot (day) of compacted bituminous mixture will be accepted when the median of the sub-lot density determinations is no less than 93.5 percent nor greater than 96.0 percent. The median shall be calculated to three significant figures.

3. If the median is not in compliance as stated above, the below equation shall apply. Compaction less than 91 percent shall result in full removal and replacement.

Loss of Asset Value for Median Compaction < 93.5% Compaction (only use for

compaction between 91% and 93.5%)

6 % 466

100

Loss of Asset Value for Median Compaction > 96% Compaction (only use for compaction

greater than 96%)

100 % 9600

4. Areas with individual compaction test results below 90 percent shall be removed and replaced regardless of the median compaction result. The limits of low compaction shall be identified at the discretion of the engineer and marked for replacement. The removal area shall be a full lane width for a minimum of 50 ft.



past the low compaction zone on both side of the identified area. Replacement shall be at no cost to the engineer.

Add Paragraph “I”” as follows:

I. Material testing and Rut test compliance criteria.

Rut Test Compliance:

For production, the contractor shall obtain rut cores from two separate random locations per 2000 tons (or fractions thereof) per mix design per day for acceptance. Rut cores shall be tested at 76 degrees C in air. If the day’s paving includes multiple lifts, then each lift shall be cored and tested. One set of companion cores shall be delivered to the Engineer for correlation testing.

The cores shall be acquired from each lift. If the lift is greater than three (3) inches, the core shall be cut at each two inch thickness and rut tested. If multiple lifts are cored, it is permitted to rut test on the cut face. The cores must be taken and patched prior to opening to traffic.

The pavement rut testing acceptance criteria for production placements shall be as listed below, or as otherwise specified in the project plans or contract documents:

1. When a paving day includes a bus stop or a bus lane that is within 300 lineal feet of an intersection, one of the cores shall be taken within 100 feet prior to the location of where the bus stops or prior to 300 feet of the intersection. All of the cores must be removed and patched prior to opening to traffic.

2. The average of all the Contractor cores for the day’s placement shall be the determining factor for acceptance of each lift of paving.

3. If multiple lifts are placed in one day, the contractor may core through multiple lifts to obtain all cores at the same time. However each lift must be rut tested. The rut test may be performed on the cut face between each lift if contractor proves that testing on a cut face provides reliable and accurate results.

4. Acceptance shall be based upon an 8,000-cycle rut test. If the average daily rut exceeds 2.5 mm, with no one value greater than 3.5 mm, then the below loss of asset equation shall apply.

Rut Test Bid Item Asset Reduction

∗ 0.1364 1))

x= mm over 2.5 at 8000 cycles

If the asset loss is less than 85%, the deficient pavement limits shall be identified, removed and replaced.

Tensile Strength Ratio (TSR):



1. If the ratio is less than the minimum, there shall be a bid item reduction of or portion thereof based on the below Equation. Pavement with TSR Values less than 60% shall be fully removed and replaced.

TSR Bid Item Reduction for test results between 60 and 75

1.333

100

Marshall testing:

1. Meet the minimum design requirement. Pavement not complying with the minimum shall be removed and replaced.

Percent asphalt content compliance:

1. Percent asphalt content shall be within 0.2 percent of the target asphalt content. If the sample is more than 0.2 percent below the target asphalt content, contractor shall remove and replace the pavement represented by that sample. If asphalt content is more than 0.2 percent and less than 0.4 percent above the target asphalt content, then the loss of asset equation below shall apply. If the asphalt content is more than 0.4 percent above the target asphalt content, contractor shall remove and replace the pavement represented by that sample.

Percent Asphalt Cement over Contract Specification Bid Item Reduction

75 ∗ % 110

100

2. If a loss asset reduction has been applied to the percent asphalt, the loss asset demerit for the air voids shall not apply.

3. Gradation Percent passing the 1/2 inch, #4, #30, and #200: Average to be within the production range. If any one item is out of the required range, there shall be a loss asset reduction of $1.00 per mix ton times the percentage out of range.

4. A printout for each 200 tons of Continuous Plant produced material and final printout report shall include the following:

1. Project bid number

2. Mix design number

3. Accumulated total wet tonnage

4. Accumulated binder weight



5. Accumulated aggregate bin weights

If a dispute occurs for the percent binder in a placed mix, and if the hotplant asphalt cement has a definite start and stop period for a project, and as approved by the Engineer, the total weight of the binder with the total weight of the aggregate, as per the mix design, may be used as acceptance.

The hotplant printout shall demonstrate that the plant is set at the required asphalt cement content. If the setting is not within a tolerance set range of plus or minus 0.1 percent, and if the change has not been approved by the engineer, the project shall have bid item reduction of $ 10.00 per ton per 0.1% percent asphalt deviation or portion thereof.

The hotplant printout shall demonstrate that the plant is set at the required recycled asphalt content. If the recycle setting is not within a tolerance set range of plus or minus 2.0 percent, and if the change has not been approved by the engineer, the project shall have penalty bid item reduction of $ 5.00 per ton per percent recycle deviation or portion thereof.

401.02.14 JOINTS


B. Longitudinal joints shall be spaced so that joints in succeeding courses will be at least 12 inches horizontally from joints in any preceding course. Lanes will be evened up each day to eliminate cold longitudinal joints insofar as practicable. No two longitudinal joints shall be constructed within the same traffic lane.

Add Paragraph “E” to this subsection:

E. The acceptance of the longitudinal joint shall be based on average of densities acquired each 400 linear feet within 3 inches of the joint. The individual compaction test shall be no lower than 91 percent and shall not be included in the 5,000 square foot testing lot. Joint edge compaction equipment may be used in order to increase the compaction of the joint. For joint compaction, the bid item reduction shall be based on three feet wide for the distance of the deficiency.

Joint compactions will be taken adjacent to the randomly selected density locations specified herein. Construct longitudinal joints with a minimum density of 91% of the target density. When joint densities fall below 91%, the loss of asset value equation below shall apply.

Loss of Asset Value for Joint Compaction < 91% Compaction (only use for compaction less than 91%)

5 % 360

100



401.03.17 (NDOT) PLANTMIX BITUMINOUS PAVEMENTS This project includes a roadway maintained by the Nevada Department of Transportation and is subject to the Standard Drawings and Specifications developed by that public agency. Information regarding the requirements of NDOT is available on the Internet at https://www.nevadadot.com/doing-business/contractors-construction/contract-services/standard-specifications-and-plans Roadway in this project that will be subject to NDOT guidelines is Blue Diamond Road. The following revisions apply to the Nevada Department of Transportation’s 2014 Standard Specifications for Road and Bridge Construction (Silver Book). (NDOT) 401.03.05 Weather Limitations. In addition to the temperature limitations specified in this Subsection of the NDOT Standard Specifications, do not place plantmix bituminous open-graded surface between November 1 and April 1. The last paragraph of this Subsection of the NDOT Standard Specifications is hereby deleted and the following substituted therefore:

Place open-graded plantmix bituminous surface only when the atmospheric temperature and the pavement surface temperature are above 21 C (70 F).

METHOD OF MEASUREMENT

401.04.01 MEASUREMENT This subsection is changed to read as follows: The quantity of 3-Inch Plantmix Bituminous Pathway shall be measured for payment by area in square yards. The quantity of Asphalt Curb measured for payment will be the number of linear feet along the base of the curb face. The measurement of 6-3/4” Plantmix Bituminous Surface shall be measured by the metric ton (ton) of completed mixture of aggregate, asphalt, and mineral filler. The measurement of Plantmix Bituminous Open-Graded Surface (1-Inch) shall be measured by the metric ton (ton) of completed mixture of aggregate, asphalt, and mineral filler.

BASIS OF PAYMENT 401.05.01 PAYMENT The following is added to this subsection:



The accepted quantities of 3-Inch Plantmix Bituminous Pathway, measured as provided above, will be paid for as specified in the Section 402. The accepted quantities of Asphalt Curb, measured as provided above, will be paid for as specified in the Section 402. The accepted quantities of 6-3/4” Plantmix Bituminous Surface, measured as provided above, will be paid for as specified in the Section 402. The accepted quantities of Plantmix Bituminous Open-Graded Surface (1-Inch), measured as provided above, will be paid for as specified in the Section 403.



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