ESBD_417187_1746803326876_02. Specification TxDOT 845-63-66352.pdf

TEXAS DEPARTMENT OF TRANSPORTATION

SPECIFICATION NO.

TxDOT 845-63-66352

DATED: APRIL 2025

1-5

SUPERPAVE GYRATORY COMPACTOR

PUBLICATION

This specification is a product of the Texas Department of Transportation (TxDOT). This specification may not be sold for profit or monetary gain. If this document is altered in any way, the header and any and all references to TxDOT shall be removed. TxDOT does not assume nor accept any liability when this specification is used in the procurement process by any other entity.

1. SCOPE: This Specification is to purchase a Superpave Gyratory Compactor.

2. DELIVERY LOCATION: The unit must be delivered to the Texas Department of

Transportation, 600 W. Interstate 2, Pharr, TX 78577. Attn: Sergio Cantu

3. DEFINITIONS OF TERMS AND ACRONYMS

3.1. ANSI – American National Standards Institute

3.2. HMA – Hot Mix Asphalt

3.3. TxDOT – Texas Department of Transportation

3.4. ID – Inside Dimension

3.5. AASHTO – American Association of Highway and Transportation Officials.

3.6. ASTM – American Society for Testing and Materials.

3.7. kN - Kilonewtons

4. EQUIPMENT

4.1. Equipment furnished must be the latest model in current production, as offered to commercial trade, and of quality workmanship and material. The vendor represents that all equipment offered will be new. Used, shopworn, demonstrator, prototype, re-manufactured, or discontinued models are not acceptable.

4.2. All parts not specifically mentioned which are necessary for the unit to be complete and ready for operation or which are normally furnished as standard equipment must be furnished by the vendor. All parts must conform in strength, quality, and workmanship to the accepted standard of the industry.

4.3. The equipment must produce cylindrical specimens from loose hot mix asphalt (HMA) by applying vertical consolidation pressure combined with a gyratory (kneading) compaction method. This method must simulate the long-term effects of traffic on pavement performance.

4.4. The equipment must be an electromechanical system for both operation and control.

4.5. The compactor must weigh at least 880 pounds (400 kilograms) to ensure stability and reliable operation during use.

TxDOT 845-63-66352

DATED: APRIL 2025

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4.6. The equipment must meet all requirements of Tex-241-F, Test Procedures for Compacting Bituminous Specimens Using the Superpave Gyratory Compactor (see Attachment A).

4.7. The equipment must meet all requirements of AASHTO T 312-22, Standard Test Method for Preparing and Determining the Density of Asphalt Mixtures by Means of the Superpave Gyratory Compactor (see Attachment B).

4.8. The equipment must meet all requirements of ASTM D6925-23, Standard Test Method for Preparation and Determination of Relative Density of Asphalt Mixtures by Means of the Superpave Gyratory Compactor (see Attachment C).

5. COMPACTION CHAMBER

5.1. The equipment must be completely enclosed and provide sufficient workspace to allow the mold to be charged, positioned within the compaction chamber, and extruded without requiring the mold to be lifted.

5.2. The compaction chamber must include a window in the door to allow for visual observation during operation.

5.3. The compaction chamber must be equipped with an emergency stop switch for immediate shutdown of the system.

5.4. The compaction chamber must include a self-aligning ram and mold carriage assembly to ensure proper alignment during operation.

5.5. The equipment must maintain a gyration speed of 30 ± 0.5 gyrations per minute, held constant throughout the compaction process.

5.6. The compactor must be capable of compacting specimens with a programmable range of 1 to 999 gyrations, with automatic shutoff upon reaching the specified number.

5.7. The consolidation pressure must be applied using a mechanical screw-driven ram mechanism.

6. GYRATORY MOLD ASSEMBLIES AND RAM HEADS

6.1. The gyratory compactor must be supplied with three mold assemblies, each with an inside diameter (ID) of 150 mm. All dimensional tolerances must be verified at room temperature, between 20°C and 22°C.

6.2. A simple and effective tool or method for extruding specimens from the gyratory mold must be included with the compactor.

7. RECORDING AND DATA OUTPUT

7.1. Specimen height must be measured, recorded, and displayed once per gyration, with changes limited to within ± 0.1 mm. Measurements shall be based either on the mechanical screw’s rotation or calculated per gyration.

7.2. Data acquisition capabilities must include tracking of gyration number, specimen height (in millimeters), angle of gyration (in degrees), and consolidation pressure (in kilopascals).

7.3. It must be possible for the operator to set the desired number of gyrations, with the system capable of storing data from at least 20 previously compacted specimens.

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7.4. For data transfer and download, the system shall include one RJ45 Ethernet port and a minimum of two USB ports.

7.5. Electrical operation must be compatible with standard 110/115 VAC, 12 AMP, 50/60 Hz, single-phase power supply.

8. CALIBRATION

8.1. The gyratory compactor must be supplied with all necessary calibration tools to enable accurate measurement or verification of consolidation pressure, specimen height, and the external gyratory angle.

8.2. Calibration capabilities must include multi-point procedures, with a minimum of 10 calibration points for both force and height to ensure precision.

8.3. Required calibration tools must include:

8.3.1. A certified 5,000 lb. (approximately 22.2 kN) maximum load ring.

8.3.2. A certified height calibration block.

9. ADDITIONAL SPECIFICATIONS:

9.1. The unit must be equipped with a built-in specimen extruder.

9.2. Compaction must be programmable to stop based on a target number of gyrations, a specified specimen height, or a locking point.

9.2.1. The compactor must be capable of producing molded specimens with a diameter of 150 mm (5.9 in.) and adjustable in height from 62 ± 1 mm (2.40 ± 0.04 in.) to 115 ± 5 mm (4.5 ± 0.2 in.).

9.2.2. Height adjustments must be possible without requiring recalibration of the unit.

9.3. The equipment must support compaction at either a specified internal or external angle of gyration.

9.4. A manual mold locking mechanism must be provided.

9.5. Approximate maximum equipment dimensions must not exceed the following:

9.5.1. Width 875 mm (34.5 in.)

9.5.2. Depth 900 mm (35.5 in.)

9.5.3. Height 1375 mm (54 in.)

10. ACCESSORIES:

10.1. A supply of 150 mm paper disks must be included.

10.2. A funnel suitable for use with a 150 mm mold must be provided.

10.3. A 150 mm specimen lift handle must be included.

10.4. One container of the manufacturer’s recommended lubricant must be supplied with the unit.

11. FACTORY TRAINED TECHNICIAN:

The vendor must provide the services of a competent factory-trained technician thoroughly trained in the use and operation of the unit to TxDOT for a minimum of 4-hour(s) instruction

DATED: APRIL 2025

4-5 on safety, operation, and preventive maintenance of the unit. Services must be provided after the unit has been delivered and is ready for operation but prior to payment. The training must take place on TxDOT's premises at a time and date mutually agreed upon by the vendor and TxDOT.

NOTE: Please include installation, calibration, and freight charges in the unit price of the bid tab.

12. EXAMPLE MAKE/MODLES

12.1. Pine- Model AFG2A

12.2. Gilson- Model HM-685

Or in accordance with paragraph 2.01 Specification of the TxDOT Terms and Conditions.

13. DELIVERABLES

13.1. One Super Gyratory Compactor

13.2. Factory Trained Technician

14. WARRANTY REQUIREMENTS

14.1. MATERIAL WARRANTY: Materials provided under the contract must be in current production, as offered to commercial trade, and be of quality material. Used, shopworn, demonstrator, prototype, reconditioned, or discontinued materials are not acceptable. Materials must be warranted against material defects and defects in workmanship for a period of not less than 12 months and cover 100% parts and labor. The warranty period must commence upon date of acceptance by TxDOT. If the manufacturer’s standard warranty period exceeds 12 months, then the standard warranty period must be in effect. The vendor must be responsible for the warranty.

The vendor must provide the designated TxDOT representative with all manufacturers’ warranty documents upon completion of service prior to leaving the job site.

15. VENDOR PERFORMANCE: Vendor performance will be monitored on a regular basis by TxDOT.

15.1. An unsatisfactory performance determination includes, but is not limited to:

15.1.1. Failure to deliver any portion of the equipment.

15.1.2. Any requirement not met as outlined in the equipment requirements determined by TxDOT.

NOTE: Unsatisfactory performance may result in a negative vendor performance report, or cancellation of the contract or both, in addition to any other rights, liquidated damages and remedies provided by the contract or allowed by law.

15.2. An exceptional performance determination includes, but is not limited to:

15.2.1. Deliverables made early upon TxDOT personnel request.

15.2.2. Product upgrade substitution suggested and accepted at no additional cost to TxDOT.

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15.2.3. Vendor commended for exceptional customer service; exceptional service provided.

15.2.4. Provided technical assistance when not required.

MATERIALS AND TESTS DIVISION 1 – 8 EFFECTIVE DATE: APRIL 2025

REVIEW DATE: APRIL 2025

Test Procedure for

COMPACTING BITUMINOUS SPECIMENS USING THE

SUPERPAVE GYRATORY COMPACTOR (SGC)

TxDOT Designation: Tex-241-F Effective Date: April 2025

1. SCOPE

1.1 Use this test method to:

compact cylindrical specimens of hot-mix asphalt (HMA) using the Superpave gyratory compactor;

prepare specimens for determining the mechanical and volumetric properties of HMA; and Note 1—The specimens simulate density, aggregate orientation, and structural characteristics obtained in the actual roadway when proper construction procedure is used in the placement of the paving mix.

monitor the density of test specimens during their preparation and for field control of an HMA production process.

1.2 Refer to Table 1 for Superpave and conventional mix nomenclature equivalents. Replace conventional nomenclature with Superpave nomenclature when required.

Table 1 Nomenclatures and Definitions

Nomenclatures Definitions

Conventional Superpave

Ga Gmb Bulk specific gravity of the compacted mixture

Gr Gmm Theoretical maximum specific gravity

1.3 The values given in parentheses (if provided) are not standard and may not be exact mathematical conversions. Use each system of units separately. Combining values from the two systems may result in nonconformance with the standard.

2. APPARATUS

2.1 Superpave gyratory compactor (SGC).

2.1.1 The compactor is an electrohydraulic or electromechanical compactor with ram and ram heads that are restrained from revolving during compaction.

2.1.2 The axis of the ram is perpendicular to the platen of the compactor.

2.1.3 The compactor tilts the specimen molds at an internal angle of 1.16 ± 0.02° (20.2 ± 0.35 mrad) and gyrates specimen molds at a rate of 30.0 ± 0.5 gyrations per minute throughout compaction.

Purchase of Superpave Gyratory Compactor for Materials and Tests Division Attachment A SPECIFICATION NO.

DATED: APRIL 2025

COMPACTING BITUMINOUS SPECIMENS USING THE SUPERPAVE GYRATORY

COMPACTOR (SGC) TXDOT DESIGNATION: TEX-241-F

MATERIALS AND TESTS DIVISION 2 – 8 EFFECTIVE DATE: APRIL 2025

REVIEW DATE: APRIL 2025

2.1.4 The compactor is designed to permit the specimen mold to revolve freely on its tilted axis during gyration.

2.1.5 The ram applies and maintains a pressure of 600 ± 18 kPa (87 ± 2 psi) perpendicular to the cylindrical axis of the specimen during compaction.

Note 2—This stress calculates to 10,600 ± 310 N (2,383 ± 70 lbf) total force for 150 mm (5.912 in.)

specimens.

2.2 Specimen height measurement and recording device.

2.2.1 When monitoring specimen density during compaction, provide a means to continuously measure and record the height of the specimen to the nearest 0.1 mm during compaction, once per gyration.

Note 3—Specimen height monitoring is for informational purposes only during design.

2.2.2 The system should be capable of downloading or printing test information, such as specimen height per gyration. In addition to a printer, the system may include a computer and suitable software for data acquisition and reporting.

2.3 Specimen molds.

2.3.1 Specimen molds must have steel walls that are at least 7.5 mm (0.3 in.) thick and have a minimum Rockwell hardness HR-C 48.

2.3.2 Molds must have an inside diameter of 149.90–150.00 mm (5.901–5.912 in.) and be at least 250 mm (10 in.)

high.

2.3.3 The inside finish of the molds must have a root mean square (rms) of 1.60 μm or smoother.

Note 4—Measure smoothness according to ANSI B46.1. One source of supply for a surface compactor, which is used to verify the rms value of 1.60 μm, is GAR Electroforming, Danbury, Connecticut.

2.4 Ram heads and mold bottoms.

2.4.1 Ram heads and mold bottoms must be fabricated from steel with a minimum Rockwell hardness of C48.

2.4.2 The ram heads must be perpendicular to its axis.

2.4.3 The platen side of each mold bottom must be flat and parallel to its face.

2.4.4 All ram and base plate faces (the sides presented to the specimen) must be ground flat to meet the smoothness requirements of ANSI B 46.1 and must have a diameter of 149.50–149.75 mm (5.885–

5.896 in.).

2.5 Mercury thermometer, marked in 5°F (3°C) divisions or less, or a digital thermometer capable of measuring the temperature specified in this test procedure.

2.6 Balance, Class G2 in accordance with Tex-901-K, with a minimum capacity of 10000 g.

2.7 Oven, capable of maintaining a temperature of at least 325°F (163°C).

2.8 Pans, metal, with flat bottom.

2.9 Metal material handling chute.

2.10 Scoop, spatula, trowel.

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REVIEW DATE: APRIL 2025

2.11 Paper disks.

2.12 Insulating gloves.

2.13 Lubricating materials per manufacturers recommendations.

3. SAFETY PRECAUTIONS

3.1 Use standard safety precautions and protective clothing when handling hot asphalt mixtures, molds, and equipment.

4. CALIBRATION

4.1 Items requiring periodic verification of calibration include:

ram pressure, angle of gyration, gyration frequency, linear variable differential transducer (LVDT) [or other means used to continuously record the specimen height], and oven temperature.

4.2 Verification of the mold and platen dimensions and the inside finish of the mold are also required.

4.3 When the computer and software options are used, periodically verify the data processing system output using a procedure designed for such purposes.

4.4 The manufacturer, other agencies providing such services, or in-house personnel may perform the verification of the calibration system standardization and quality checks. Frequency of verification must follow manufacturer’s recommendations.

5. PREPARATION OF THE SGC

5.1 Turn on the compactor and allow it to warm up before the asphalt concrete mixture is ready for placement in the mold.

5.2 Verify settings for angle and pressure.

5.3 Select gyration or height mode. Enter the design number of gyrations or required specimen height according to the specification or test procedure.

Note 5—Gyration mode is normally used when molding samples for volumetric properties. Height mode is normally used when molding samples for performance testing such as Hamburg, Overlay, Cantabro, and Indirect Tensile Strength Test (IDT).

5.4 Lubricate bearing surfaces as needed.

5.5 Lubricate the surface of the rotating base and the surface of the four rollers.

5.6 Follow the instructions in Sections 5.6.1 – 5.6.2 when monitoring the specimen height.

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5.6.1 Before placing the material in the mold, turn on the device for measuring and recording the height of the specimen. Verify that the readout is in the proper units (mm) and that the recording device is ready.

5.6.2 If using a computer, prepare it to record the height data and enter the header information for the specimen.

6. MIXTURE PREPARATION

6.1 For laboratory-produced mixtures, proceed to Section 6.2. For plant-produced mixtures, proceed to Section 6.3. For mixtures requiring re-heating, proceed to Section 6.4. For hot-mix cold-laid (HMCL) and limestone rock asphalt (LRA) mixtures, proceed to Section 6.5.

Note 6—Mixtures requiring re-heating are defined as laboratory or plant-produced mixtures that will be cooled to ambient temperature and transported to another laboratory for testing.

6.2 Laboratory-Produced Mixtures:

6.2.1 Combine aggregates and prepare the laboratory mixture as described in Tex-205-F.

6.2.2 Split the mixture into the appropriate sample size.

Note 7—The sample weight of test specimens will vary based on the selected compaction method and the test to be performed. If a target density is desired for performance testing, adjust the sample weight to create a given density for a specified height. If the specimens are to be used for determining volumetric properties, adjust the sample weight to yield results based on gyration control.

6.2.3 Proceed to Section 6.6.

6.3 Plant-Produced Mixtures:

6.3.1 Sample the plant-produced mixture in accordance with Tex-222-F.

6.3.2 Split the mixture into the appropriate sample size. Refer to Note 7.

6.3.3 Proceed to Section 6.6.

6.4 Plant-Produced or Lab-Produced Mixtures Requiring Re-Heating:

6.4.1 For plant-produced mixtures, sample the mixture in accordance with Tex-222-F. For laboratory produced mixtures, combine aggregates and prepare the laboratory mixture as described in Tex-205-F.

6.4.2 If transferring the material to a different lab for testing, place the material in a paper bag or cardboard box for shipping and labeling. The sample thickness in the container must not exceed 3 in.

Note 8—Do not use canvas sacks as shipping containers.

Note 9—Do not send in pre-molded specimens when submitting material for performance tests such as IDT, IDEAL-CT, Hamburg, Cantabro, and Overlay.

6.4.3 Proceed to Section 6.6.

6.5 HMCL and LRA Mixtures:

6.5.1 Place HMCL mixtures in an oven and cure to constant weight at a minimum temperature of 140°F (60°C) to remove moisture and hydrocarbon volatiles.

Note 10—Constant weight is the weight at which further oven drying does not alter the weight by more than 0.05% in a 2 hr. or longer drying interval in accordance with Section 9.3.

MATERIALS AND TESTS DIVISION 5 – 8 EFFECTIVE DATE: APRIL 2025

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6.5.2 Place LRA mixtures in an oven and cure to constant weight at 190 ± 10°F (88 ± 5°C) with frequent stirring.

6.5.3 Remove LRA mixtures from the oven and let them cool down to 100 ± 5°F (38 ± 3°C) before compaction.

6.5.4 Proceed to Section 6.6.

6.6 Select the compaction temperature from Table 2 based on the performance grade (PG) specified on the plans. Only use the target discharge temperature as the compaction temperature when it is less than the temperature shown in Table 2. Set the oven to match the temperature selected from Table 2.

Note 11—If using reclaimed asphalt pavement (RAP) or recycled asphalt shingles (RAS) and a substitute PG binder instead of the PG binder originally specified, defer to the originally specified binder grade when selecting the compaction temperature.

6.7 Place the compaction mold, base, and the top plate in an oven at the selected compaction temperature for a minimum of 60 min. before compaction.

6.8 Place the material into an oven at the selected compaction temperature. For laboratory or plant-produced mixtures samples that do not require reheating, proceed to Section 6.8.1. For shipped laboratory or plant-produced mixture that requires reheating, proceed to Section 6.8.2.

6.8.1 Remove the sampled material from the sampling container and place it into a large pan. Thoroughly mix the sample and split into the appropriate sample size and place into a metal pan. Refer to Note 7. Spread the material in the metal pan at a uniform thickness of 2.25 in. ± 0.5 in. and place the split samples back into the oven. Cure the mix in the oven for 2 hr. ± 5 min. Monitor the internal temperature of the mix by inserting a calibrated thermometer or temperature probe into the loose material and leaving in the oven. If the internal temperature of the mixture has not reached the specified compaction temperature after the 2-hr. cure, continue to monitor the sample every 15 min. until the compaction temperature has been reached. Once the sample mixture has reached the specified compaction temperature and the curing period is complete, proceed to Section 8 to mold the specimen.

6.8.2 Place the sealed sample container into the oven at the selected compaction temperature until the material can be easily broken apart. Remove the sampled material from the container and place it into a large pan.

Thoroughly mix the sample and split into the appropriate sample size and place into a metal pan. Refer to Note 7. Spread the material in the metal pan at a uniform thickness of 2.25 in. ± 0.5 in. and place the split samples back into the oven. Cure the mix in the oven for 1.5 hr. ± 5 min. at the selected curing temperature.

Monitor the internal temperature of the mix by inserting a calibrated thermometer or temperature probe into the loose material and leaving it in the oven. If the internal temperature of the mixture has not reached the specified compaction temperature after the 1.5 hr. cure, continue to monitor the sample every 15 min. until the compaction temperature has been reached. Once the sample mixture has reached the specified compaction temperature and the curing period is complete, proceed to Section 8 to mold the specimen.

Note 12—When molding samples for performance testing, trial samples are often required to determine proper mold weights. To ensure proper sample aging, do not leave loose material in the oven while the trial is being performed.

Note 13—When molding samples to a target height of 62 mm, a circular pan with the following dimensions will meet the required curing thickness: top diameter of 10.25 in. and a bottom diameter of 8.5 in. A rectangular pan with the following dimensions will meet the required curing thickness: length of 10.25 in., width of 12.81 in., and depth of 2.5 in.

Note 14—When molding samples to a target height of 115 mm, a circular pan with the following dimensions will meet the required curing thickness: top diameter of 12.5 in. and a bottom diameter of 9.75 in. A rectangular pan with the following dimensions will meet the required curing thickness: length of 10.25 in., width of 12.81 in., and depth of 4 in.

MATERIALS AND TESTS DIVISION 6 – 8 EFFECTIVE DATE: APRIL 2025

REVIEW DATE: APRIL 2025

7. COMPACTION TEMPERATURES

7.1 Use the compaction temperatures in Table 2 when molding samples. Use the same temperature for both curing and compaction of these mixtures.

7.2 Compaction temperatures not listed in Table 2 may be used when shown on the plans or approved by the Engineer. For guidance on materials not listed in Table 2 or materials containing modifying additives, RAP, or RAS, consult the Flexible Pavements Section of the Materials and Tests Division.

Table 2 Curing and Compaction Temperatures

Binder1 Temperature, °F2 Asphalt LRA3 100 Asphalt HMCL 140

PG 58 – 28, PG 64 – 22 250

PG 64 – 28, PG 70 – 22 275

PG 70 – 28, PG 76 – 22, PG 76 – 28 300

Asphalt Rubber (A-R) 300

PG 82 – 28, HPG 325

Note: Mixtures must be compacted at the selected compaction temperature within a tolerance of ± 5°F (± 3°C).

1.If using RAP or RAS and a substitute PG binder instead of the PG binder originally specified on the plans, defer to the originally specified binder grade when selecting the compaction temperature.

2.Only use the target discharge temperature when it is less than the compaction temperature shown.

3.The Curing temperature for LRA is 190°F.

8. PROCEDURES

8.1 Compaction:

8.1.1 Use the design number of gyrations (Ndes) or height for compaction according to the specification or as shown on the plans.

Note 15—When the mixture appears dry and lacking asphalt, lower the Ndes value to increase the optimum asphalt content of the mixture.

8.1.2 Following oven curing, remove the heated mold and base plate from the oven and place a paper disk on the bottom of the mold.

8.1.3 To minimize segregation, place the mixture into the metal material handling chute by quickly inverting the pan upside down. Use the metal material handling chute to then place material into the mold in one lift. Take care to avoid segregation in the mold.

8.1.4 After all the mix is in the mold, level the mix with a spatula and place another paper disk and the top plate on the leveled material.

8.1.5 Load the specimen mold into the compactor and center the mold under the loading ram.

8.1.6 Press the start button to lower the ram. The pressure on the specimen should reach 600 ± 18 kPa (87 ± 2 psi).

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8.1.7 The compactor should then apply a 1.16 ± 0.02° (20.2 ± 0.35 mrad) internal angle to the mold assembly and begin the gyratory compaction.

8.1.8 Allow compaction to proceed until completion of the specified number of gyrations or height and until the gyratory mechanism shuts off.

8.1.8.1 When monitoring the specimen height, record the specimen height to the nearest 0.1 mm (0.004 in.) after each revolution.

8.1.9 Once the machine removes the angle from the mold assembly and raises the loading ram, remove the mold from the compactor, and extrude the specimen from the mold.

Note 16—Do not immediately extrude the specimen from the mold for lean, rich, and tender mixtures, for mixtures containing asphalt rubber binder, or for mixtures compacted to a density less than 82% to prevent deformation of the specimen. Allow the mold to cool for approximately 10 min. or more in front of a fan.

8.1.10 Carefully remove the paper disks from the top and bottom of the specimens.

Note 17—When molding multiple specimens, place the mold in the oven for at least 5 min. before reusing.

The use of multiple molds will expedite the compaction process.

8.2 Density:

8.2.1 Use the maximum specific gravity (Gr) of the loose mix determined in accordance with Tex-227-F using a trial sample. For permeable friction course (PFC) mixtures, use a back-calculated Gr in accordance with Tex-207- F.

Note 18—Oven-cure the trial sample at the same temperature and for the same length of time as the compaction sample.

8.2.2 Record the mass of the extruded specimen to the nearest 0.1 g and determine the bulk specific gravity (Ga) of the extruded specimen in accordance with Tex-207-F.

8.2.3 Calculate the relative density of the extruded specimen (%Gmm) in accordance with Section 9.1.

Note 19—Estimations of the relative density of the specimen can be made at any point in the compaction process based on the specimen height in accordance with Section 9.2.

9. CALCULATIONS

9.1 Calculate %Gmm:

100*% r a mm G

GG

Where:

%Gmm = relative density of the extruded specimen expressed as a percent of the theoretical maximum specific gravity Ga = bulk specific gravity of the extruded specimen Gr = theoretical maximum specific gravity of the mix

9.1.1 Report results to the nearest 0.1%.

9.2 Estimate the percent compaction (%Gmmx) at any point in the compaction process:

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REVIEW DATE: APRIL 2025

100% xr ma mmx hG hGG

Where:

%Gmmx = relative density expressed as a percentage of the theoretical maximum specific gravity

Ga = bulk specific gravity of the extruded specimen

Gr = theoretical maximum specific gravity of the mix hm = height of the extruded specimen, mm hx = height of the specimen after “x” gyrations, mm

9.2.1 Report results to the nearest 0.1%.

9.3 Calculate the percent difference in weight: = ℎ − ℎ ℎ 100

10. ARCHIVED VERSIONS

10.1 Archived versions are available.

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Purchase of Superpave Gyratory Compactor for Materials and Tests Division Attachment B SPECIFICATION NO.

; < = > ? ; @ A > = A B B < C ; D

A E A E

This standard covers the compaction of cylindrical specimens of asphalt mixtures using the

Superpave gyratory compactor. A E > E This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. A E @ E The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of R 18 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with R 18 alone does not completely assure reliable results. Reliable results depend on many factors; following the suggestions of R 18 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors. > E A E AASHTO Standards:

M 231, Weighing Devices Used in the Testing of Materials

M 339M/M 339, Thermometers Used in the Testing of Construction Materials

R 18, Establishing and Implementing a Quality Management System for Construction

Materials Testing Laboratories

R 30, Mixture Conditioning of Asphalt Mixtures

R 35, Superpave Volumetric Design for Asphalt Mixtures

R 47, Reducing Samples of Asphalt Mixtures to Testing Size

R 97, Sampling Asphalt Mixtures

T 166, Bulk Specific Gravity (Gmb) of Compacted Asphalt Mixtures Using Saturated Surface-

Dry Specimens

T 209, Theoretical Maximum Specific Gravity (Gmm) and Density of Asphalt Mixtures

T 275, Bulk Specific Gravity (Gmb) of Compacted Asphalt Mixtures Using Paraffin-Coated

SpecimensF G H G I J K L M N O P N Q R S T U O V V W S R T L R W U W X Y L T L N Z R [ M \ T K T U ] ^ Q T U V _ W Q L T L R W U ` X X R S R T a V bO a a Q R [ M L V Q N V N Q c N ] b d e _ a R S T L R W U R V T c R W a T L R W U W X T _ _ a R S T J a N a T \ b� � � � � � � � � � � � � � � ! " # � $ � � % � & � ' ! ( � ! � ) # ' � � & � ' ! � ! * � + , � � ' " - � ' . * � / � ! � + % � ! � " 0 ' * � & ' 1 2 3 4 " 5 2 " 3 3 , # / 1 6 1 2 + 7 8 � � � ' � � � " 1 6 9 : 4 9 : 1 3 : 1 5 9

; < = > ? ; @ A > = > B B < C ; D

T 316, Viscosity Determination of Asphalt Binder Using Rotational Viscometer

T 344, Evaluation of Superpave Gyratory Compactor (SGC) Internal Angle of Gyration Using

Simulated Loading> E > E ASTM Standards:

E1, Standard Specification for ASTM Liquid!in!Glass Thermometers

E230/E230M, Standard Specification for Temperature!Electromotive Force (emf) Tables for

Standardized Thermocouples

E2877, Standard Guide for Digital Contact Thermometers> E @ E International Electrotechnical Commission Standard:

IEC 60584!1: 2013 Thermocouples ! Part 1: EMF Specifications and Tolerances> E f E Other Standards:

ANSI/ASME B89.1.6, Measurement of Qualified Plain Internal Diameters for Use as Master

Rings and Ring Gages

ANSI/ASME B89.4.19, Performance Evaluation of Laser-Based Spherical Coordinate

Measurement Systems

ASME B46.1, Surface Texture (Surface Roughness, Waviness, and Lay)@ E A E This standard is used to prepare specimens for determining the mechanical and volumetric properties of asphalt mixtures. The specimens simulate the density, aggregate orientation, and structural characteristics obtained in the actual roadway when proper construction procedure is used in the placement of the paving mix. @ E > E This test method may be used to monitor the density of test specimens during their preparation. It may also be used for field control of an asphalt mixture production process. f E A E Superpave Gyratory Compactor—An electrohydraulic or electromechanical compactor with a ram and ram heads as described in Section 4.3. The axis of the ram shall be perpendicular to the platen of the compactor. The ram shall apply and maintain a pressure of 600 18 kPa perpendicular to the cylindrical axis of the specimen during compaction (Note 1). The compactor shall tilt the specimen molds at an average internal angle of 20.2 ± 0.35 mrad (1.16 ± 0.02 degrees), determined in accordance with T 344. The compactor shall gyrate the specimen molds at a rate of 30.0 0.5 gyrations per minute throughout compaction.g � � � h —This stress calculates to 10 600 310 N total force for 150-mm specimens.f E A E A E

Specimen Height Measurement and Recording Device—When specimen density is to be monitored during compaction, a means shall be provided to continuously measure and record the height of the specimen to the nearest 0.1 mm during compaction once per gyration. f E A E > E The system may include a connected printer capable of printing test information, such as specimen height per gyration. In addition to a printer, the system may include a computer and suitable software for data acquisition and reporting.

F G H G I J K L M N O P N Q R S T U O V V W S R T L R W U W X Y L T L N Z R [ M \ T K T U ] ^ Q T U V _ W Q L T L R W U ` X X R S R T a V bO a a Q R [ M L V Q N V N Q c N ] b d e _ a R S T L R W U R V T c R W a T L R W U W X T _ _ a R S T J a N a T \ b� � � � � � � � � � � � � � � ! " # � $ � � % � & � ' ! ( � ! � ) # ' � � & � ' ! � ! * � + , � � ' " - � ' . * � / � ! � + % � ! � " 0 ' * � & ' 1 2 3 4 " 5 2 " 3 3 , # / 1 6 1 2 + 7 8 � � � ' � � � " 1 6 9 : 4 9 : 1 3 : 1 5 9

; < = > ? ; @ A > = @ B B < C ; D f E A E @ E The loading system, ram, and pressure indicator shall be capable of providing and measuring a constant vertical pressure of 600 ± 60 kPa during the first five gyrations, and 600 ± 18 kPa during the remainder of the compaction period. f E > E Specimen Molds—Specimen molds shall have steel walls that are at least 7.5 mm thick and are hardened to at least a Rockwell hardness of C48. The initial inside finish of the molds shall have a root mean square (rms) of 1.60 m or smoother when measured in accordance with ASME B46.1

(see Note 2). New molds shall be manufactured to have an inside diameter of 149.90 to

150.00 mm. The inside diameter of in-service molds shall not exceed 150.2 mm. Molds shall be at least 250 mm in length. The inside diameter and length of the molds shall be measured in accordance with Annex A. g � � � � —One source of supply for a surface comparator, which is used to verify the rms value of

1.60 m, is GAR Electroforming, Danbury, Connecticut.f E @ E Ram Heads and End Plates—Ram heads and end plates shall be fabricated from steel with a minimum Rockwell hardness of C48. The ram heads shall stay perpendicular to their axis. The platen side of each end plate shall be flat and parallel to its face. All ram and end plate faces (the sides presented to the specimen) shall be flat to meet the smoothness requirement in Section 4.2 and shall have a diameter of 149.50 to 149.75 mm. f E f E Thermometers—Thermometers for measuring temperature of aggregates, binder, and asphalt mixtures shall meet the requirements of M 339M/M 339 with a temperature range of at least 10 to

230°C, and an accuracy of ±2.5°C (±4.5°F) (see Note 3). g � � � i —Thermometer types suitable for use include ASTM E1 mercury thermometers; ASTM

E230/E230M thermocouple thermometer, Type J, any Class, or Type K, Class 1 or 2; IEC 60584 thermocouple thermometer, Type J, any Class, or Type K, Class 1 or 2; ASTM E2877 digital metal stem thermometer; or dial gauge metal stem (bi-metal) thermometer. f E j E Balance—A balance meeting the requirements of M 231, Class G 5, for determining the mass of aggregates, binder, and asphalt mixtures. f E k E Oven—An oven, thermostatically controlled to 3 C, for heating aggregates, binder, asphalt mixtures, and equipment as required. The oven shall be capable of maintaining the temperature required for mixture conditioning in accordance with R 30. f E l E Miscellaneous—Flat-bottom metal pans for heating aggregates, scoop for batching aggregates, containers (grill-type tins, beakers, containers for heating asphalt), large mixing spoon or small trowel, large spatula, gloves for handling hot equipment, paper disks, mechanical mixer (optional), lubricating materials recommended by the compactor manufacturer. f E m E Maintenance—In addition to routine maintenance recommended by the manufacturer, check the

Superpave gyratory compactor’s mechanical components for wear, and perform repair, as recommended by the manufacturer. j E A E Use standard safety precautions and protective clothing when handling hot materials and preparing test specimens. k E A E Items requiring periodic verification of calibration include the ram pressure, angle of gyration, gyration frequency, LVDT (or other means used to continuously record the specimen height), and F G H G I J K L M N O P N Q R S T U O V V W S R T L R W U W X Y L T L N Z R [ M \ T K T U ] ^ Q T U V _ W Q L T L R W U ` X X R S R T a V bO a a Q R [ M L V Q N V N Q c N ] b d e _ a R S T L R W U R V T c R W a T L R W U W X T _ _ a R S T J a N a T \ b� � � � � � � � � � � � � � � ! " # � $ � � % � & � ' ! ( � ! � ) # ' � � & � ' ! � ! * � + , � � ' " - � ' . * � / � ! � + % � ! � " 0 ' * � & ' 1 2 3 4 " 5 2 " 3 3 , # / 1 6 1 2 + 7 8 � � � ' � � � " 1 6 9 : 4 9 : 1 3 : 1 5 9

; < = > ? ; @ A > = f B B < C ; D oven temperature. Verification of the mold and platen dimensions and the inside finish of the mold are also required. When the computer and software options are used, periodically verify the data-processing system output using a procedure designed for such purposes. Verification of calibration, system standardization, and quality checks may be performed by the manufacturer, other agencies providing such services, or in-house personnel. Frequency of verification shall follow the manufacturer’s recommendations. k E > E The angle of gyration refers to the internal angle (the tilt of the mold with respect to the end plate surface within the gyratory mold). The calibration of the internal angle of gyration shall be verified in accordance with T 344. l E A E Immediately prior to the time when the asphalt mixture is ready for placement in the mold, turn on the main power for the compactor for the manufacturer’s required warm-up period. l E > E Verify the machine settings are correct for angle, pressure, and number of gyrations. l E @ E Lubricate any bearing surfaces as needed per the manufacturer’s instructions. l E f E When specimen height is to be monitored, the following additional item of preparation is required.

Immediately prior to the time when the asphalt mixture is ready for placement in the mold, turn on the device for measuring and recording the height of the specimen, and verify the readout is in the proper units, mm, and the recording device is ready. Prepare the computer, if used, to record the height data, and enter the header information for the specimen. m E A E Laboratory Prepared: m E A E A E Weigh the appropriate aggregate fractions into a separate pan, and combine them to the desired batch weight. The batch weight will vary based on the ultimate disposition of the test specimens.

If a target air void level is desired, as would be the case for Superpave mix analysis and performance specimens, batch weights will be adjusted to create a given density in a known volume. If the specimens are to be used for the determination of volumetric properties, the batch weights will be adjusted to result in a compacted specimen having dimensions of 150 mm in diameter and 115 5 mm in height at the desired number of gyrations.g � � � n —It may be necessary to produce a trial specimen to achieve this height requirement.

Generally, 4500 to 4700 g of aggregate are required to achieve this height for aggregates with combined bulk specific gravities of 2.550 to 2.700, respectively. m E A E > E Place the aggregate and binder container in the oven, and heat them to the required mixing temperature. m E A E > E A E The mixing temperature range is defined as the range of temperatures where the unaged binder has a viscosity of 0.17 0.02 Pa s when measured in accordance with T 316.g � � � o —Modified asphalts may not adhere to the equiviscosity requirements noted, and the manufacturer’s recommendations should be used to determine mixing and compaction temperatures. m E A E @ E Charge the mixing bowl with the heated aggregate from one pan and dry-mix thoroughly. Form a crater in the dry-blended aggregate, and weigh the required amount of binder into the mix.

Immediately initiate mixing. F G H G I J K L M N O P N Q R S T U O V V W S R T L R W U W X Y L T L N Z R [ M \ T K T U ] ^ Q T U V _ W Q L T L R W U ` X X R S R T a V bO a a Q R [ M L V Q N V N Q c N ] b d e _ a R S T L R W U R V T c R W a T L R W U W X T _ _ a R S T J a N a T \ b� � � � � � � � � � � � � � � ! " # � $ � � % � & � ' ! ( � ! � ) # ' � � & � ' ! � ! * � + , � � ' " - � ' . * � / � ! � + % � ! � " 0 ' * � & ' 1 2 3 4 " 5 2 " 3 3 , # / 1 6 1 2 + 7 8 � � � ' � � � " 1 6 9 : 4 9 : 1 3 : 1 5 9

; < = > ? ; @ A > = j B B < C ; D m E A E f E Mix the aggregate and binder as quickly and thoroughly as possible to yield an asphalt mixture having a uniform distribution of binder. As an option, mechanical mixing may be used. m E A E j E After completing the mixture preparation, perform the required mixture conditioning in accordance with R 30. m E A E k E Place the compaction mold(s) in an oven at the required compaction temperature for a minimum of 30 min prior to the estimated beginning of compaction (during the time the mixture is being conditioned in accordance with R 30). Place any additional compaction surfaces, such as base plates and upper plates, into the oven with and for the same time frame as the molds, according to the manufacturer’s instructions. m E A E l E Following the mixture conditioning period specified in R 30, if the mixture is at the compaction temperature, proceed immediately with the compaction procedure as outlined in Section 9. If the compaction temperature is different from the mixture conditioning temperature used in accordance with R 30, place the mix in another oven at the compaction temperature for a brief time (maximum of 30 min) to achieve the required temperature. m E A E l E A E The compaction temperature is the midpoint of the range of temperatures where the unaged binder has a viscosity of 0.28 0.03 Pa s when measured in accordance with T 316. (See Note 5.)m E > E Plant Produced: m E > E A E Place the compaction mold(s) in an oven at the required compaction temperature (see Section

8.1.7.1). Place any additional compaction surfaces, such as base plates and upper plates, into the oven with and for the same time frame as the molds, according to the manufacturer’s instructions. m E > E > E Obtain the sample in accordance with R 97. m E > E @ E Reduce the sample in accordance with R 47. m E > E f E Place the sample into a pan to a uniform thickness. m E > E j E Bring the asphalt mixture to the compaction temperature range by careful, uniform heating in an oven immediately prior to molding. p E A E When the compaction temperature is achieved, remove the heated mold and any compaction surfaces from Section 8.1.6 or 8.2.1 from the oven. Place the base plate and a paper disk in the bottom of the mold. p E > E Place the mixture into the mold in one lift. Care should be taken to avoid segregation in the mold.

After all the mix is in the mold, level the mix, and place another paper disk on top of the leveled material. Complete any remaining mold assembly, load the mold into the compactor, and center the loading ram according to the manufacturer’s instructions. p E @ E Apply a pressure of 600 18 kPa on the specimen.p E f E Apply a 20.2 ± 0.35 mrad (1.16 ± 0.02 degrees) average internal angle to the mold assembly and begin the gyratory compaction. p E j E Allow the compaction to proceed until the desired number of gyrations specified in R 35 is reached and the gyratory mechanism shuts off. F G H G I J K L M N O P N Q R S T U O V V W S R T L R W U W X Y L T L N Z R [ M \ T K T U ] ^ Q T U V _ W Q L T L R W U ` X X R S R T a V bO a a Q R [ M L V Q N V N Q c N ] b d e _ a R S T L R W U R V T c R W a T L R W U W X T _ _ a R S T J a N a T \ b� � � � � � � � � � � � � � � ! " # � $ � � % � & � ' ! ( � ! � ) # ' � � & � ' ! � ! * � + , � � ' " - � ' . * � / � ! � + % � ! � " 0 ' * � & ' 1 2 3 4 " 5 2 " 3 3 , # / 1 6 1 2 + 7 8 � � � ' � � � " 1 6 9 : 4 9 : 1 3 : 1 5 9

; < = > ? ; @ A > = k B B < C ; D p E k E Remove the angle from the mold assembly, remove the ram pressure, and retract the loading ram in the order specified by the SGC manufacturer (the preceding steps may be done automatically by the compactor on some models of SGCs). Remove the mold from the compactor (if required) and extrude the specimen from the mold. g � � � q —No additional gyrations with the angle removed are required unless specifically called for in another standard referencing T 312. The extruded specimen may not be a right-angle cylinder. Specimen ends may need to be sawed to conform to the requirements of specific performance tests. g � � � r —The specimens can be extruded from the mold immediately after compaction for most asphalt mixtures. However, a cooling period of 5 to 10 min in front of a fan may be necessary before extruding some specimens to ensure the specimens are not damaged. p E l E Remove the paper disks from the top and bottom of the specimens. g � � � s

—Before reusing the mold, place it in an oven for at least 5 min. The use of multiple molds will speed up the compaction process. A t E A E Determine the maximum specific gravity (Gmm) of the loose mix in accordance with T 209 using a companion sample. The companion sample shall be conditioned to the same extent as the compaction sample. A t E > E Determine the bulk specific gravity (Gmb) of the specimen in accordance with T 166 or T 275 as appropriate. A t E @ E When the specimen height is to be monitored, record the specimen height to the nearest 0.1 mm after each revolution. A A E A E Calculate the uncorrected relative density (%Gmmux) at any point in the compaction process using the following equation:

% 100m mmux mx mm m

W G

V G G (1) where:

%Gmmux = uncorrected relative density at any point during compaction expressed as a percent of the maximum theoretical specific gravity;

Wm = mass of the specimen, g;

Gmm = theoretical maximum specific gravity of the mix;

Gm = unit weight of water, 1 g/cm3;

x = number of gyrations; and

Vmx = volume of the specimen, in cm3, at any point based on the diameter (d) and height (hx) of the specimen at that point (use “mm” for height and diameter measurements).

It can be expressed as:

4 1000 x mx d h V (2)

F G H G I J K L M N O P N Q R S T U O V V W S R T L R W U W X Y L T L N Z R [ M \ T K T U ] ^ Q T U V _ W Q L T L R W U ` X X R S R T a V bO a a Q R [ M L V Q N V N Q c N ] b d e _ a R S T L R W U R V T c R W a T L R W U W X T _ _ a R S T J a N a T \ b� � � � � � � � � � � � � � � ! " # � $ � � % � & � ' ! ( � ! � ) # ' � � & � ' ! � ! * � + , � � ' " - � ' . * � / � ! � + % � ! � " 0 ' * � & ' 1 2 3 4 " 5 2 " 3 3 , # / 1 6 1 2 + 7 8 � � � ' � � � " 1 6 9 : 4 9 : 1 3 : 1 5 9

; < = > ? ; @ A > = l B B < C ; D g � � � u —This formula gives the volume in cm3 to allow a direct comparison with the specific gravity. A A E > E At the completion of the bulk specific gravity test (Gmb), determine the relative density (%Gmmx) at any point in the compaction process as follows:

% 100mb m mmx mm x

G h G

G h (3) where:

%Gmmx = corrected relative density expressed as a percent of the maximum theoretical specific gravity;

Gmb = bulk specific gravity of the extruded specimen;

hm = height in millimeters of the extruded specimen; and hx = height in millimeters of the specimen after x gyrations. A > E A E Report the following information in the compaction report, if applicable: A > E A E A E Project name; A > E A E > E Date of the test; A > E A E @ E Start time of the test; A > E A E f E Specimen identification; A > E A E j E Percent binder in specimen, nearest 0.1 percent; A > E A E k E Average diameter of the mold used (d), nearest 1.0 mm; A > E A E l E Mass of the specimen (Wm), nearest 0.1 g; A > E A E m E Maximum specific gravity (Gmm) of the specimen by T 209, nearest 0.001; A > E A E p E Bulk specific gravity (Gmb) of the specimen by T 166 or T 275, nearest 0.001; A > E A E A t E Height of the specimen after each gyration (hx), nearest 0.1 mm; A > E A E A A E Relative density (%Gmm) expressed as a percent of the theoretical maximum specific gravity

(Gmm), nearest 0.1 percent; and A > E A E A > E Gyration angle, nearest 0.2 mrad (0.01 degrees), and the method used to determine or verify the gyration angle. A @ E A E Precision: A @ E > E Single-Operator Precision—The single operator standard deviations (1s limits) for relative densities at Nini and Ndes for mixtures containing aggregate with an absorption of less than

1.5 percent are shown in Table 1. The results of two properly conducted tests on the same F G H G I J K L M N O P N Q R S T U O V V W S R T L R W U W X Y L T L N Z R [ M \ T K T U ] ^ Q T U V _ W Q L T L R W U ` X X R S R T a V bO a a Q R [ M L V Q N V N Q c N ] b d e _ a R S T L R W U R V T c R W a T L R W U W X T _ _ a R S T J a N a T \ b� � � � � � � � � � � � � � � ! " # � $ � � % � & � ' ! ( � ! � ) # ' � � & � ' ! � ! * � + , � � ' " - � ' . * � / � ! � + % � ! � " 0 ' * � & ' 1 2 3 4 " 5 2 " 3 3 , # / 1 6 1 2 + 7 8 � � � ' � � � " 1 6 9 : 4 9 : 1 3 : 1 5 9

; < = > ? ; @ A > = m B B < C ; D material, by the same operator, using the same equipment, should be considered suspect if they differ by more than the d2s single operator limits shown in Table 1.