Supporting Materials for NCHRP Report 673 (2011)

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F-1 APPENDIX F: TUTORIAL 206

F-2 TUTORIAL This self-study document is meant to familiarize technicians and engineers with the most important parts of the Manual and with the HMA Tools spreadsheet. The first part of this tutorial covers Chapters 3, 4, and 5 of the manual, which cover asphalt binders, aggregates, and volumetric composition, respectively. For each chapter, you should read the chapter and then answer the questions presented in the tutorial. You should then correct your work using the answers given on the following page in the tutorial. For any incorrect answers, you should go back to the manual and review the section that covers the topic the question dealt with, and make sure you understand the correct answer to the question. The largest part of the tutorial is an example mix design, which involves information covered in Chapter 8 of the manual on the design of dense-graded HMA mixtures. Because the example mix design includes reclaimed asphalt pavement (RAP), it also involves much of the information covered in Chapter 9. The example is done in a step-by-step fashion, giving the reader instructions for each part of the mix design and then presenting the solution on the following page. The mix design has been done using the HMA Tools spreadsheet, so readers will find it easier to follow if they use HMA Tools when working through the mix design. As discussed on the last page of the tutorial, there are four technical chapters not covered in the tutorial: Chapter 7. Selection of Asphalt Concrete Mix Type Chapter 10. Design of Gap-Graded HMA Mixtures Chapter 11. Design of Open-Graded Mixtures Chapter 12. Field Adjustments and Quality Assurance of HMA Mixtures Many technicians and engineers will not have need of the information in these chapters on a regular basis. Others, however will find that they do need the information in one or more of these chapters, in which case they should be carefully read. The amount of time required to work through this tutorial will vary from person to person, depending on their level of experience and how carefully they work. Experienced technicians and engineers working quickly might be able to complete this tutorial in a few hours. Technicians and engineers new to the HMA industry working more slowly might require an entire day to complete the work. 207

F-3 Chapter 3. Asphalt Binders After studying Chapter 3 of the manual, answer the questions below. 1. The stiffness of most asphalt binders changes very little with temperature ( true / false). 2. What are the upper and lower pavement temperatures for a PG 64-22 binder? 3. What are the two common methods for laboratory aging of asphalt binders? 4. What three specification tests are performed on asphalt binders using the dynamic shear rheometer? 5. What are the two tests used to control low temperature properties of asphalt binders? 6. The following properties were measured for an asphalt binder. Does this material meet all the requirements for a PG 76-16 binder? Test Temperature, °C Result Tests on original binder Flash Point --- 327°C Viscosity 135 4.7 Pa-s Dynamic shear rheometer, G*/sin δ at 10 rad/s 76 1.07 kPa Tests on residue from thin-film oven test Mass loss --- 0.6% Dynamic shear rheometer, G*/sin δ at 10 rad/s 76 2.05 kPa Tests on residue from pressure aging vessel Dynamic shear rheometer, G* sin δ at 10 rad/s 34 5,617 kPa Bending beam rheometer, stiffness at 60 s -6 238 MPa Bending beam rheometer, m-value at 60 s -6 0.287 208

F-4 Chapter 3. Asphalt Binders Solutions 1. The stiffness of most asphalt binders changes very little with temperature ( true / false). False (see pages 3-1 and 3-2). 2. What are the upper and lower pavement temperatures for a PG 64-22 binder? Upper pavement temperature 64 °C, lower pavement temperature -22 °C (see pages 3-4 and 3-5). 3. What are the two methods normally used for laboratory aging of asphalt binders? The rolling thin-film oven test, or RTFOT, and the pressure aging vessel, or PAV (see pages 3-7 and 3-8). 4. What three specification tests are performed on asphalt binders using the dynamic shear rheometer? The high-temperature test on original binder, high-temperature test on RTFOT residue, and intermediate-temperature test on PAV residue (see pages 3-8 through 3-10). 5. What are the two tests used to control low temperature properties of asphalt binders? The bending beam rheometer or the direct tension test (see pages 3-10 through 3-12). 6. The following properties were measured for an asphalt binder. Does this material meet all the requirements for a PG 76-16 binder? The viscosity at 135 °C is too high. The value for G*/sin δ at 76 °C on the rolling thin-film oven test residue is too low. The value of G* sin δ at 34 °C on the pressure aging vessel residue is too high. The m-value measured with the bending beam rheometer at -6 °C is too low. See Table 3-1 on pages 3-13 through 3-15. 209

F-5 Chapter 4. Aggregates After studying Chapter 4 of the manual, answer the questions below. 1. What are the definitions of coarse aggregate, fine aggregate, and mineral filler? 2. For a 12.5 mm nominal maximum aggregate size, what is the minimum sample size for a sieve analysis? 3. For the data below on a sieve analysis of a fine aggregate, calculate % retained, cumulative % retained and % passing for each sieve size and complete the table. Also, calculate the error for the sieve analysis. (1) Sieve Size, mm (2) Weight Retained, g (3) % Retained, Wt.% (4) Cumulative % Retained, Wt.% (5) % Passing, Wt.% 19.0 0.0 12.5 0.0 9.5 85.4 4.75 195.6 2.36 207.5 1.18 238.0 0.60 202.7 0.30 153.4 0.15 85.9 0.075 55.6 pan 47.2 Total: Original Sample Size: 1276.3 Error, Wt.%: 4. What are typical specific gravity values for the following aggregates: diabase, limestone, sandstone, basalt? What is the typical specific gravity of asphalt cement binder? 210

F-6 5. The following test data was gathered during a specific gravity determination on a coarse aggregate sample: Dry weight of aggregate in air: 2,307.7 g Weight of saturated, surface-dry aggregate in air: 2,315.2 g Weight of aggregate in water: 1,432.6 g What is the bulk specific gravity of this aggregate? 6. What are the standard specification properties (previously called “Superpave consensus properties”) for coarse and fine aggregate? 7. For an HMA mixture designed for a traffic level of 23 million ESALs, what are the required values for the various aggregate specification properties? 211

F-7 Chapter 4. Aggregates Solutions 1. What are the definitions of coarse aggregate, fine aggregate, and mineral filler? Coarse aggregate is that which is retained on the 2.36 mm sieve, while fine aggregate is that which passes the 2.36 mm sieve. Mineral filler passes the 0.075-mm sieve (see page 4-1). 2. For a 12.5 mm nominal maximum aggregate size, what is the minimum sample size for a sieve analysis? 2 kg (see Table 4-1 on page 4-4). 3. For the data below on a sieve analysis of a fine aggregate, calculate % retained, cumulative % retained and % passing for each sieve size and complete the table. Also, calculate the error for the sieve analysis. The completed table is given below (see pages 4-5 through 4-7). (1) Sieve Size, mm (2) Weight Retained, g (3) % Retained, Wt.% (4) Cumulative % Retained, Wt.% (5) % Passing, Wt.% 19.0 0.0 0.0 0.0 100.0 12.5 0.0 0.0 0.0 100.0 9.5 85.4 6.7 6.7 93.3 4.75 195.6 15.3 22.0 78.0 2.36 207.5 16.3 38.3 61.7 1.18 238.0 18.6 56.9 43.1 0.60 202.7 15.9 72.8 27.2 0.30 153.4 12.0 84.8 15.2 0.15 85.9 6.7 91.6 8.4 0.075 55.6 4.4 95.9 4.1 pan 47.2 3.7 99.6 0.4 Total: 1271.3 99.6 Original Sample Size: 1276.3 Error, Wt.%: 0.39 212

F-8 4. What are typical specific gravity values for the following aggregates: diabase, limestone, sandstone, basalt? What is the typical specific gravity of asphalt cement binder? Diabase: 2.96; limestone, 2.66; sandstone, 2.54; basalt, 2.86. The typical specific gravity of asphalt cement binder is 1.03 (see Table 4-5 on page 4-13). 5. The following test data was gathered during a specific gravity determination on a coarse aggregate sample: Dry weight of aggregate in air: 2,307.7 g Weight of saturated, surface-dry aggregate in air: 2,315.2 g Weight of aggregate in water: 1,432.6 g What is the bulk specific gravity of this aggregate? Bulk specific gravity = A / (B – C) = 2,307.7/(2,315.2 – 1,432.6) = 2.615 See pages 4-13 and 4-14. 6. What are the standard specification properties (previously called “Superpave consensus properties”) for coarse and fine aggregate? For coarse aggregate: fractured faces and flat and elongated particles. For fine aggregate: fine aggregate angularity (uncompacted voids) and clay content/sand equivalent (see pages 4-18 through 4-27). 7. For an HMA surface course mixture (to be placed entirely within 100 mm of the pavement surface), designed for a traffic level of 23 million ESALs, what are the required values for the various aggregate specification properties? Coarse aggregate fractured faces: 95% minimum with at least one fractured face, 90% minimum with at least two fractured faces Flat and elongated particles: 10% maximum Fine aggregate angularity: 45% minimum uncompacted voids Clay content: 45% minimum sand equivalent value See pages 4-18 through 4-27. 213

F-9 Chapter 5. Mixture Volumetric Composition After studying Chapter 5 of the manual, answer the questions below. 1. If a core from a pavement has a density of 94.2%, what the air void content of the core? 2. An HMA mixture has a total asphalt content of 6.0% by total mix weight, and the aggregate absorbs 0.5% of the asphalt binder. What is the effective asphalt content of this mixture? 3. An HMA mixture contains 3.5% air voids, and has an effective asphalt content of 11.3% by volume. What is the VMA for this mixture? 4. The theoretical maximum specific gravity of an HMA mixture is being determined in a laboratory. The data for the test are given below. Mass of oven-dry mixture in air: 1,205.2 g Mass of container filled with water at 25°C: 2,307.4 g Mass of container with mixture filled with water at 25°C: 3,025.7 g What is the theoretical maximum specific gravity for this mixture? 5. A compacted HMA specimen has a bulk specific gravity of 2.372. The theoretical maximum specific gravity for this mixture is 2.448. What is the air void content of this specimen? 214

F-10 Chapter 5. Mixture Volumetric Composition Solutions 1. If a core from a pavement has a density of 94.2%, what the air void content of the core? The air void content would be 100 – 94.2 = 5.8% (see page 5-5). 2. An HMA mixture has a total asphalt content of 6.0% by total mix weight, and the aggregate absorbs 0.5% of the asphalt. What is the effective asphalt content of this mixture? The effective asphalt content is 6.0 - 0.5 = 5.5% by total mix weight (see page 5-7 or Equation 5-8 on page 5-22). 3. An HMA mixture contains 3.5% air voids, and has an effective asphalt content of 11.3% by volume. What is the VMA for this mixture? The VMA would be 11.3 + 3.5 = 14.8% by volume (see page 5-8 /or Equation 5-11 on page 5-22). 4. The theoretical maximum specific gravity of an HMA mixture is being determined in a laboratory. The data for the test are given below. Mass of oven-dry mixture in air: 1,205.2 g Mass of container filled with water at 25°C: 2,307.4 g Maxx of container with mixture filled with water at 25°C: 3,025.7 g What is the theoretical maximum specific gravity for this mixture? Gmm = A / (A + D – E) = 1,205.2 / (1,205.2 + 2,307.4 – 3,025.7) = 2.475 See pages 5-15 through 5-17 and Equation 5-2. 5. A compacted HMA specimen has a bulk specific gravity of 2.372. The theoretical maximum specific gravity for this mixture is 2.448. What is the air void content of this specimen? VA = 100 [ 1 – (Gmb/Gmm)] = 100 [1 – (2.372/2.448)] = 3.10% See Equation 5-4 on page 5-20. 215

F-11 Chapters 8 and 9: Dense-Graded HMA Mix Design Example Please read through Chapters 8 and 9 of the Mix Design Manual and then work through this example mix design, which will take you through most of the steps of a typical HMA mix design. You should work through the problem using the HMA Tools spreadsheet, if possible. If you want to use another spreadsheet or computer program, it should obtain the same results, but it will be much easier to follow through the example and the solution if you use HMA Tools. Enter General Information for the Mix Design Listed below is general information for the mix design example. Enter this information in HMA Tools on worksheet “General.” Project: “Tutorial” To be placed within 100 mm of surface: yes Dust/binder ratio: standard Specified binder grade: PG 64-22 (25°C intermediate grade) Design traffic level: 800,000 ESALs Nominal maximum aggregate size, mm: 12.5 Turn to the next page to see what the worksheet “General” should now look like. 216

F-12 GENERAL INFORMATION Date (mm/dd/yyyy): 1/19/2009 Project: Tutorial Tech./Engr.: J. Doe NMAS (size in mm): 12.5 To be placed within 100 mm of surface (yes/no): Yes Traffic Level (million ESALs): 0.8 Dust/Binder ratio (standard/low): standard Specified Binder PG Grade, PG- 64-22 Specified High Temperature PG Grade: 64 Specified Low Temperature PG Grade: -22 Specified Intermediate Temperature PG Grade: 25 Compactor Manufacturer and Model: Pine Compactor Angle Calibration Method: PG 76-22 Binder or Higher (yes/no) no Ndesign 75 Minimum VMA: 14.0 Maximum VMA: 16.0 Midpoint VMA/Suggested Target VMA: 15.0 Select Target VMA: Select Target Air Voids (4.0 % suggested, +/- 0.5 %): Minimum Dust/Binder Ratio: 0.8 Maximum Dust/Binder Ratio: 1.6 Maximum Allowable RAP Content CA Fractured Faces, One Fractured Face, Min. % 75 CA Frctured Faces, Two Fractured Faces, Min. % 0 Retained on CA Flat & Elongated, 5:1 Ratio, Max. % 10 Sieve, mm #N/A #N/A FA Angularity, Uncompacted Voids, Min. % 40 Passing Sand Equivalent, Min. % 40 Sieve, mm #N/A #N/A Notice that the values for Ndesign, VMA, dust/binder ratio, and aggregate specification properties are automatically calculated and displayed on the worksheet. Select Target VMA and Air Voids For most HMA mix designs, the target VMA should be approximately halfway between the minimum and maximum values—in this example, 15.0%. The target air void content should normally be 4.0%. Fill out cells C23 and C24 with these values. The green cells appearing with the aggregate specification properties are for adding user-defined aggregate specification properties. In this example, we won’t use any additional aggregate specification properties. We will fill out the maximum allowable RAP value later in the mix design. 217

F-13 Enter Aggregate Gradation, Specific Gravity and Specification Propery Values The table below lists aggregate gradation data, specific gravity values and specification property data for four aggregates that will be used in this example mix design. Use this information to complete the “Aggregates” worksheet in HMA Tools. Sieve Size, mm Percent passing for aggregate: Coarse 1 Coarse 2 Coarse 3 Mfg. Fines 37.5 100.0 100.0 100.0 100.0 25.0 100.0 100.0 100.0 100.0 19.0 100.0 100.0 100.0 100.0 12.5 99.7 100.0 100.0 100.0 9.5 49.6 65.8 100.0 100.0 4.75 1.3 2.6 56.0 99.1 2.36 0.7 1.3 2.6 75.6 1.18 0.7 1.3 1.6 50.2 0.60 0.7 1.3 1.6 34.1 0.30 0.7 1.3 1.6 24.0 0.15 0.7 1.3 1.6 16.1 0.075 0.7 1.3 1.6 10.0 Specific Gravity Values Bulk Gs 2.704 2.680 2.628 2.666 Apparent Gs 2.742 2.735 2.713 2.737 Aggregate Specification Property Data CAFF (1 face/ 2 faces) 100/99 100/98 100/99 Flat & elongated, Wt.% 2.0 4.0 2.0 FAA, Uncomp. voids,% 47.4 Clay content, sand equivalent,% 66.4 Turn to the next page to see what the completed worksheet “Aggregates” should now look like. 218

F-14 AGGREGATE PROPERTIES Help Appears Below Aggregate Name/Code Coarse 1 Coarse 2 Coarse 3 Mfg. Fines Bulk Spec. Grav. 2.704 2.680 2.628 2.666 Apparent Spec. Grav. 2.742 2.735 2.713 2.737 Water Absorption 0.51 0.75 1.19 0.97 CAFF, One Fractured Face, % 100.0 100.0 100.0 CAFF, Two Fractured Faces, % 99.0 98.0 99.0 Flat & Elong., % 2.0 4.0 2.0 FAA, Uncompacted Voids 47.4 Sand Eq. 66.4 Size, mm 50.000 100.0 100.0 100.0 100.0 37.500 100.0 100.0 100.0 100.0 25.000 100.0 100.0 100.0 100.0 19.000 100.0 100.0 100.0 100.0 12.500 99.7 100.0 100.0 100.0 9.500 49.6 65.8 100.0 100.0 4.750 1.3 2.6 56.0 99.1 2.360 0.7 1.3 2.6 75.6 1.180 0.7 1.3 1.6 50.2 0.600 0.7 1.3 1.6 34.1 0.300 0.7 1.3 1.6 24.0 0.150 0.7 1.3 1.6 16.1 0.075 0.7 1.3 1.6 10.0 Sieve Analysis, Weight % Passing Make sure that the data on the percentage of one and two fractured faces are entered separately in the correct cells. 219

F-15 Calculate Average RAP properties and Maximum Allowable RAP Content Based on Variability. Standards and specification for designing HMA mixtures containing RAP vary widely among different agencies. Technicians and engineers responsible for preparing HMA mix designs should follow the standards applicable in their state, or standards specified by the owner on privately funded projects. In the approach used in the Manual and HMA Tools, it is assumed no grade adjustments or variability analysis are needed if the RAP content is 15% or less. At RAP contents greater than 15%, a variability analysis must be performed, in which the maximum amount of RAP that can be added to the mix without exceeding normal production variability limits is calculated. This ensures that adding RAP to your mix will not cause your production variability to exceed specified limits. This analysis is separate from the asphalt binder performance grade analysis, which might result in a separate limit on RAP content for the mix design. The RAP binder analysis is covered later in this tutorial. Listed below are gradation and asphalt content data for five RAP samples taken from different spots in the RAP stockpile. Use this data to fill out the worksheet “RAP_Variability,” under stockpile 1 (HMA Tools can handle up to four different RAP stockpiles). Sieve Size, mm % Passing for Sample: Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 37.5 100.0 100.0 100.0 100.0 100.0 25.0 100.0 100.0 100.0 100.0 100.0 19.0 100.0 100.0 100.0 100.0 100.0 12.5 99.1 98.6 97.5 99.6 99.5 9.5 96.1 93.5 92.2 94.4 97.2 4.75 73.3 69.5 67.2 73.3 74.2 2.36 57.4 53.0 51.9 56.8 56.7 1.18 46.2 40.7 39.4 43.7 44.6 0.60 34.8 31.3 28.6 31.6 35.8 0.30 23.1 21.8 19.8 22.0 22.5 0.15 15.7 13.5 13.4 14.2 14.9 0.075 11.1 9.2 8.5 9.8 11.2 Asphalt Binder Content, Wt.% 3.8 3.3 3.2 3.4 3.7 Turn to the next page to see what the completed worksheet looks like. 220

F-16 RAP STATISTICS ANALYSIS OF RAP VARIABILITY AND ESTIMATED MAXIMUM RAP CONTENT 80.0 100 31 Enter in cell D28 on Worksheet General SAMPLE NUMBER: 1 2 3 4 5 6 7 8 9 10 11 Average Std. Dev. Sieve Size, mm 100.0 0.000 50.000 100.0 100.0 100.0 100.0 100.0 100.0 0.000 37.500 100.0 100.0 100.0 100.0 100.0 100.0 0.000 25.000 100.0 100.0 100.0 100.0 100.0 100.0 0.000 19.000 100.0 100.0 100.0 100.0 100.0 98.9 0.856 12.500 99.1 98.6 97.5 99.6 99.5 94.7 1.999 9.500 96.1 93.5 92.2 94.4 97.2 71.5 3.011 4.750 73.3 69.5 67.2 73.3 74.2 55.2 2.519 2.360 57.4 53.0 51.9 56.8 56.7 42.9 2.807 1.180 46.2 40.7 39.4 43.7 44.6 32.4 2.899 0.600 34.8 31.3 28.6 31.6 35.8 21.8 1.246 0.300 23.1 21.8 19.8 22.0 22.5 14.3 0.971 0.150 15.7 13.5 13.4 14.2 14.9 10.0 1.180 0.075 11.1 9.2 8.5 9.8 11.2 3.5 0.259 Asphalt Binder Content 3.8 3.3 3.2 3.4 3.7 ESTIMATED BLEND OF RAP STOCKPILES, WEIGHT % ESTIMATED MAXIMUM RAP CONTENT, WT.%: RAP STOCKPILE 1 RAP Stockpile 2 RAP Stockpile 3 RAP Stockpile 4 RAP Stockpile 1 Reliability Level: Again, data for up to four RAP stockpiles can be entered in this worksheet. Only the data for stockpile 1 is shown here. The estimated maximum RAP content in this case is 31%; enter this value in worksheet “General” in cell D28. 221

F-17 Enter RAP Aggregate Data Enter the average RAP aggregate gradation calculated in the previous step (cells A19:A31 of worksheet “RAP_Variability”) in worksheet “RAP_Aggregates” in cells C31:C43. Also, enter the average RAP asphalt binder content in cell C6 of “RAP_Aggregates.” The data entered in worksheet “RAP_Aggregates” can be taken from the average calculated during the RAP variability analysis, or it can be data from other sources, such as an average value determined from plant QA records. Enter a binder specific gravity value of 1.03 in cell C7 of worksheet “RAP_Aggregates.” Also, immediately below this cell enter a theoretical maximum specific gravity value of 2.489 and an estimated binder absorption value of 0.50%. The binder absorption value for RAP stockpiles can be estimated from values for similar mix designs, or from records on the RAP mixture, if available. In this example, the aggregate specific gravity is estimated from the theoretical maximum specific gravity and estimated absorption. Another approach is to determine the bulk and apparent specific gravity of the fine and coarse RAP aggregate, as produced by solvent extraction or an ignition oven. This data would be entered in cells C11:C14. Either approach can be used in HMA Tools. You will also need to enter data for consensus properties on this worksheet: Coarse aggregate fractured faces (Wt.% with at least one fractured face): 99 Coarse aggregate fractured faces (Wt.% with at least two fractured faces): 94 Flat and elongated particles (Wt.%): 3.0 Fine aggregate angularity (uncompacted voids,%): 46.7 Turn to the next page to see what the completed “RAP_Aggregates” worksheet should look like. 222

F-18 RAP Aggregates RAP 1 RAP 2 RAP 3 RAP4 Description: RSP No. 18 Binder Content, Wt. % 3.48 Binder Specific Gravity 1.030 Maximum Theoretical Specifif Gravity 2.489 Estimated Binder Absorption, Wt. % 0.50 Measured Fine Aggregate Bulk Specific Gravity Measured Coarse Aggregate Bulk Specific Gravity Measured Fine Aggregate Apparent Specific Gravity Measured Coarse Aggregate Apparent Specific Gravity RAP Aggregate Average Bulk Specific Gravity 2.590 #N/A #N/A #N/A RAP Aggregate Average Apparent Specific Gravity 2.624 #N/A #N/A #N/A RAP Water Absorption 0.50 #N/A #N/A #N/A CAFF, One Fractured Face, % 99.0 CAFF, Two Fractured Faces, % 94.0 Flat & Elong., % 3.0 0 0 FAA, Uncompacted Voids 46.7 Sand Eq. #N/A #N/A #N/A #N/A 0 0 Size, mm 50.000 100.0 37.500 100.0 25.000 100.0 19.000 100.0 12.500 98.9 9.500 94.7 4.750 71.5 2.360 55.2 1.180 42.9 0.600 32.4 0.300 21.8 0.150 14.3 0.075 10.0 Data for up to four different RAP aggregates can be entered in this worksheet. The data is carried over automatically to other parts of HMA Tools. 223

F-19 Enter Grading Data for New Binder When more than 15% RAP is used in a mix design, you must enter grading data for one or more new asphalt binders (HMA Tools allows you to enter data for up to four different new binders and binders from up to four RAP stockpiles). With these data HMA Tools can calculate the performance grade of the blended binder—new binder plus binder from the RAP—to determine if it meets the given requirements. If you aren’t using RAP in your design, or if you are using RAP but not more than 15% by total mix weight, you don’t need to enter any binder grading data. In this example, we are using more than 15% RAP, so we must enter binder grading data. Enter the following data on binder grading in worksheet “Binders.” The binder is a PG 64-22 supplied by Acme Materials, with a specific gravity of 1.024. High temperature grading on unaged binder, using dynamic shear rheometer Temperature °C G*/sin δ kPa 64 1.54 70 0.76 High temperature grading on residue from RTFOT oven, using dynamic shear rheometer Temperature, °C G*/sin δ kPa 64 3.46 70 1.62 Intermediate temperature grading on residue from pressure aging vessel, using dynamic shear rheometer Temperature °C G* sin δ kPa 19 6,183 22 4,219 25 2,845 Low temperature grading on residue from pressure aging vessel, using bending beam rheometer Temperature °C Stiffness MPa m-value −12 144 0.395 −18 365 0.312 Turn to the next page to see what the completed worksheet looks like. 224

F-20 BINDERS Grade: Producer/Description: Specific Gravity 1.024 Unaged Binder Temp. |G*|/sin delta C kPa High Temperature Grading 64 1.54 70 0.76 RTFOT Residue Temp. |G*|/sin delta C kPa High Temperature Grading 64 3.46 70 1.62 Continuous High Temp. Grade, C: 67.6 High Temperature Grade: 64 PAV Residue Temp. |G*| x sin delta C kPa Intermediate Temperature Grading 19 6,183 22 4,219 25 2,845 Continuous Intermediate Temp. Grade, C: 20.7 Intermediate Temperature Grade: 22 Temp. S m-value C Mpa Low Temp. Grading, BBR -12 144 0.395 -18 365 0.312 Continuous Critical Temp./Stiffness, C: -16.7 0.0 Continuous Critical Temp./m-value, C: -19.0 0.0 BBR Continuous Low Temp. Grade, C: -16.7 0.0 BBR Low Temperature Grade: -22 Strain at Temp. Failure C % Low Temp. Grading, Direct Tension (optional): DT Continuous Critical Temp. C: #N/A DT Low Temperature Grade: #N/A Continuous Critical Temp., BBR and DT, C: -16.7 Low Temperature Grade, BBR and DT, C: -22 Low Temp. Grade from Intermediate Temp. Grade: -28 Final Low Temperature Grade: -22 Final Binder PG Grade: PG 64-(22)-22 PG 58-28 Acme Note that HMA Tools calculates the binder grade based on the data entered. This is a PG 64- 22 binder. Because some agencies have specific requirements on intermediate temperature grading, HMA Tools also gives the intermediate temperature grading, in parentheses between the high and low temperature grades—in this example, PG 64-(22)-22 225

F-21 Enter Grading Data for RAP Binder Now, enter the data below on the grading of the recovered RAP binder in worksheet “RAP_Binders.” Again, remember that you don’t need this information if you are using less than 15% RAP in your mix design. The specific gravity of the binder is 1.03. High temperature grading on unaged binder, using dynamic shear rheometer Temperature °C G*/sin δ kPa 76 1.51 82 0.78 High temperature grading on residue from RTFOT oven, using dynamic shear rheometer Temperature, °C G*/sin δ kPa 76 3.24 82 1.63 Intermediate temperature grading on residue from pressure aging vessel, using dynamic shear rheometer Temperature °C G* sin δ kPa 22 5.087 25 3,770 28 2,813 Low temperature grading on residue from pressure aging vessel, using bending beam rheometer Temperature °C Stiffness MPa m-value −6 78 0.321 −12 158 0.285 Turn to the next page to see what the completed worksheet “RAP_Binders” should look like. 226

F-22 RAP BINDERS Specific Gravity 1.030 Unaged Binder Temp. |G*|/sin delta C kPa High Temperature Grading 76 1.51 82 0.78 RTFOT Residue Temp. |G*|/sin delta C kPa High Temperature Grading 76 3.24 82 1.63 Continuous High Temp. Grade, C: 79.4 High Temperature Grade: 76 Temp. |G*| x sin delta C kPa Intermediate Temperature Grading 22 5,087 25 3,770 28 2,813 Continuous Intermediate Temp. Grade, C: 22.2 Intermediate Temperature Grade: 25 Temp. S m-value C Mpa Low Temp. Grading, BBR -6 78 0.321 -12 158 0.285 Continuous Critical Temp./Stiffness, C: -17.5 Continuous Critical Temp./m-value, C: -9.4 BBR Continuous Low Temp. Grade, C: -9.4 BBR Low Temperature Grade: -16 Strain at Temp. Failure C % Low Temp. Grading, Direct Tension (optional): DT Continuous Critical Temp. C: #N/A DT Low Temperature Grade: #N/A Continuous Critical Temp., BBR and DT, C: -9.4 Low Temperature Grade, BBR and DT, C: -16 Low Temp. Grade from Intermediate Temp. Grade: -34 Final Low Temperature Grade: -16 Final Binder PG Grade: PG 76-(25)-16 Rap Binder 1 227

F-23 Develop Aggregate Blends for Three Trial Mixes HMA Tools makes it easy to develop aggregate blends for trial mixes. Go to worksheet “Trial_Blends.” Aggregate blends are developed by entering aggregate blend data—in percentage by weight—in cells F25:L36. Up to seven different blends can be entered. The plot in the upper left hand corner shows the control points for the given aggregate size and will plot any or all gradations. To show an aggregate blend on this plot, place an “X” in row 23 above the blend or blends that you want to plot. The plot in the upper right is a new type of plot, called a continuous maximum density gradation plot. In this plot, any part of a gradation that plots above the horizontal axis is fine graded, while parts of a gradation that plot below the horizontal axis are coarse graded. If part of gradation follows the horizontal axis very closely, it means that it is close to the maximum density gradation. The advantage of this plot is that it allows you to determine not just the gradation type of a complete aggregate blend, but also to evaluate how the gradation of a blend varies with particle size. It is useful when adjusting blends with the purpose of changing VMA. In general, the further away a gradation is from the horizontal axis, the greater the VMA will be. Just as in the Superpave system, we will develop three aggregate blends, if possible a dense/fine gradation, and dense/dense gradation and a dense/coarse gradation. “Dense/fine” means that a gradation is for a dense-graded HMA mixture, but with a finely graded aggregate. Another way of thinking of this is that a dense/fine gradation is an aggregate that is on the fine side of a dense gradation. Using trial and error and looking at the two plots, try to develop dense/fine, dense/dense and dense/coarse aggregate blends using 30% RAP. Remember that the control points should only be considered as guidelines and not absolute specification requirements. Also, you should enter the target VMA and air voids in rows 40 and 42, respectively, for each trial mixture. Use the overall target values we selected earlier—15% for VMA and 4% for air voids. In a real mix design, you can change these values slightly to refine your trial blends, but we’ll stay with these targets in this example. You can check the estimated properties of your trial gradations below the aggregate blending area in worksheet “Trial_Blends.” For examples, the dust:binder ratios for each trial are given in cells F45:L45. These values can be compared to the required range given immediately above in row 44. In cells F49:L52 the required new binder performance grade is listed for each trial mix. If you have the choice of several binder grades, this information would allow you to pick the one that would provide you with the correct final blended binder performance grade for the mixture. In cells F56:L69 you must mark the binder you are using for each trial mix. In this example, we only have one binder choice, so you should put an “X” in cells F56, G56 and H56. HMA Tools allows you to enter data for up to four new binders. If we entered data for more than one binder, we could place an “X” for whichever binder we wanted to use for a given trial mix. HMA Tools would then calculate blended binder grade information using data for the selected binder. This allows you to determine which of up to four binders will provide the best overall performance in your HMA mix. Once you mark your binder choice, HMA Tools will display the blended binder grade in cells F62:L62; this can be compared to the required binder grade given in row 61. Aggregate gradation data is given in cells B74:L86. 228

F-24 As you develop your trial blends, look through worksheet “Trial_Blends” and try to make sure all or most requirements are given. However, most volumetric information won’t be given, since it cannot be calculated until bulk and maximum specific gravity tests are performed on the trial mixes and the resulting data entered in HMA Tools. For example, in the gradation plot, the legend in the upper right-hand corner will show VMA and air void content once specific gravity measurements have been made and entered in worksheet “Specific_Gravity.” Since this hasn’t yet been done, the key just says “#NA” for all trial mixes. You might be wondering how HMA Tools calculates binder contents for the trial mixes. This is done volumetrically, by assuming that the trial mix will have the target VMA and target air voids. Of course, most of the time the trial mix won’t, but using this approach we are sure that the trial mix will have the correct amount of binder so that if the air void target is met, the VMA target will also be met. This approach is simple, and also means that we don’t have to worry about estimating optimum binder content—once the air void content is met, VMA will also be met and we will have our design binder content. After you have experimented with aggregate blending and developed gradations for three trial blends, look at the next page to see one solution for these three gradation—but remember, your trial blends will probably be a little different. That doesn’t mean they are wrong. 229

F-25 TRIAL AGGREGATE BLENDS help appears at lower right INCLUDE MAX. DENSITY GRADATION: X PLOT (X): X x x Material Gsb Gsa Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7 Coarse 1 2.704 2.742 12 12 12 Coarse 2 2.680 2.735 12 12 12 Coarse 3 2.628 2.713 10 18 26 Mfg. Fines 2.666 2.737 36 28 20 #N/A 0.000 0.000 #N/A 0.000 0.000 #N/A 0.000 0.000 #N/A 0.000 0.000 RSP No. 18 2.590 2.624 30 30 30 #N/A 0.000 0.000 #N/A 0.000 0.000 #N/A 0.000 0.000 TOTAL 100 100 100 0 0 0 0 Overall Target VMA, Vol. % Target VMA for Trial Batch, Vol. % 15.0 15.0 15.0 Overal Target Air Voids, Vol. % Target Voids for Trial Batch, Vol. % 4.0 4.0 4.0 Binder Content for Trial Batch, Wt. % 5.13 4.40 25.51 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Specified Dust/Binder Ratio: Estimated Dust/Effective Binder Ratio 1.4 1.3 1.1 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Required New PG Grade for Selected Stockpile Blends (conservative) Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7 High Temperature (Min.) 64.0 64.0 64.0 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Low Temperature/BBR (Max.) -28.0 -28.0 -28.0 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Low Temperature/DT (Max.) #N/A #N/A #N/A #DIV/0! #DIV/0! #DIV/0! #DIV/0! Intermediate Temperature (Max.) 25.0 25.9 25.1 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Select Binder (X) Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7 PG 58-28 / Acme Materials X X X / / / BINDER NO 1 1 1 ??? ??? ??? ??? SPECIFIED BINDER GRADE BLENDED GRADE, PG- 64-(22)-22 64-(25)-22 64-(22)-22 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Allowable RAP Content for Binder Grade and Variability Min. RAP for Binder Grade, Wt. % 10.0 10.0 10.0 #N/A #N/A #N/A #N/A Max. RAP for Binder Grade, Wt. % 50.0 47.7 50.0 #N/A #N/A #N/A #N/A Max. RAP for Variability, Wt. % Total RAP Content, Wt. % 29.5 29.7 23.2 #DIV/0! #DIV/0! #DIV/0! #DIV/0! 15.0 4.0 64-(25)-22 0 0.8 to 1.6 0 20 40 60 80 100 0.00 7.00 Particle Size0.45, mm % P as si ng b y W ei gh t Trial, voids/VMA No. 1, 5.4/17.8 No. 2, 3.3/15.6 No. 3, 3.6/34.5 Min., 14.0/ 3.5 Max., 16.0/ 4.5 Max. Dens. 0.075 0.60 2.36 4.75 9.5 12.5 19.0 25.0 37.5 50.0 -20 -15 -10 -5 0 5 10 15 20 0.01 0.10 D ev ia tio n fr om M ax im um D en si ty G ra da tio n coarse 230

F-26 Comments on Trial Blends Because of the size of the “Trial_Blends” worksheet, only part of the worksheet is shown above. Again, remember that your three trial blends may not look the same as the ones given above. Note that a dense/fine trial blend could not be developed, because the dust/binder ratio becomes too high—1.6. Although 1.6 is barely acceptable, the amount of mineral filler in an HMA mixture will usually increase significantly during plant production compared to the original mix design. Therefore, you should avoid developing mix designs with dust/binder ratios close to the maximum allowable value. If none of these trial mixes were to prove acceptable after volumetric analysis, it would probably be necessary to reduce the amount of RAP in the mix design and try to develop a dense/fine graded mix. The three mixes shown above all seem reasonable—they meet gradation requirements, and the blended binder meets the given requirements for the performance grade. At the bottom of the previous page, minimum and maximum allowable RAP contents are given for the trial mixes. How can you have a minimum RAP content? If you anticipate using a large amount of RAP and then select a relatively soft new binder, you might have a minimum RAP content so that the blended binder meets the given high-temperature PG requirements. Note that you have minimum and maximum RAP contents based on both binder grading requirements, and on RAP variability—remember, we earlier determined that the variability in this RAP material meant that we could not use more than 30% RAP in our mix design without having our production variability increase to unacceptably high levels. If you forgot to enter the calculated maximum RAP value in worksheet “General,” it won’t show up in this worksheet. Before continuing, you should change your three trial blends to match those given on the previous page. That way, as you continue through the tutorial your numbers on the various HMA Tools worksheets will be the same as those shown here. 231

F-27 Calculate Batch Weights for Gyratory Specimens To complete the evaluation of the trial mixes, trial batches must be prepared and gyratory specimens compacted. When preparing trial batches, aggregate stockpiles are usually broken down into different fractions and weighed out separately. This helps prevents segregation during weighing and batching. Different laboratories follow different procedures for breaking down aggregates when preparing trial batches. Most laboratories completely break down coarse aggregates—one fraction for each sieve size. Many laboratories don’t break down fine aggregate at all, but some will partially or even completely break down fine aggregate also. HMA Tools gives batch weights for each separate size fraction of coarse aggregates, and three different break downs for fine aggregate: no breakdown, partial break down and complete break down. RAP materials are not normally broken down when preparing trial batches. HMA Tools also provides asphalt weights. To have HMA Tools calculate batch weights, you must enter data in the worksheet “Batch.” This includes project information, and the number and size of specimens. You can specify both cylindrical specimens—like gyratory specimens—or beams and slabs, or both. You can also specify a certain weight of loose mix, and an extra percentage of mix to make sure that there is enough mixture for all specimens. You must also specify which trial mix (by number) you are preparing a batch for (cell O1 of worksheet “Batch”), and the air void content (cell K6). In this example, assume two 150 mm diameter, 100 mm high gyratory specimens will be prepared from trial batch 2, Specify 20% extra mix for the trial batch to make sure there will be enough mix for the gyratory specimens, and 4% air voids. The next page shows what the complete worksheet should look like. 232

F-28 BATCHING REPORT Trial Batch No.: 2 Cylinders: Dia., mm Ht., mm No. Date (mm/dd/yyyy): 150 100 2 Estimated Gmb: 2.349 Project: Pb, Wt. %: 4.40 Tech./Engr.: Pb/New, Wt. %: 3.36 NMAS (mm): 12.5 Beams/Slabs: 4.0 Specimen Vol., m^3 0.00353 Surface Course: Yes W, mm L, mm T, mm No. Extra mix, %: 20 Traffic Level (MESALs): 0.8 Total Wt., g: 9,962 Aggregate Batch Weights, grams: New Binder Wt., g: 335 Coarse Aggregate Min. Max. 37.5 50.0 0 0 0 0 0 0 0 0 0 0 0 0 25.0 37.5 0 0 0 0 0 0 0 0 0 0 0 0 19.0 25.0 0 0 0 0 0 0 0 0 0 0 0 0 12.5 19.0 3 0 0 0 0 0 0 0 33 0 0 0 9.5 12.5 573 391 0 0 0 0 0 0 124 0 0 0 4.75 9.5 552 722 754 24 0 0 0 0 687 0 0 0 2.36 4.75 7 15 915 627 0 0 0 0 483 0 0 0 Fine Aggregate 1.180 2.360 0 0 17 677 0 0 0 0 364 0 0 0 0.600 1.180 0 0 0 429 0 0 0 0 311 0 0 0 Complete 0.300 0.600 0 0 0 269 0 0 0 0 314 0 0 0 Breakdown 0.150 0.300 0 0 0 211 0 0 0 0 222 0 0 0 0.075 0.150 0 0 0 163 0 0 0 0 127 0 0 0 0.000 0.075 8 15 27 267 0 0 0 0 296 0 0 0 Partial 0.600 2.360 0 0 17 1,106 0 0 0 0 675 0 0 0 Breakdown 0.150 0.600 0 0 0 480 0 0 0 0 536 0 0 0 0.000 0.150 8 15 27 430 0 0 0 0 423 0 0 0 No Breakdown 0.000 2.360 8 15 44 2,016 0 0 0 0 1,634 0 0 0 Total Weight: 1,143 1,143 1,713 2,667 0 0 0 0 2,961 0 0 0 Loose Mix, g: Compacted Specimens & Loose Mix: Tutorial J. Doe Size Fractions, mm: #N/A#N/A #N/A #N/A #N/A Target Air Voids, %: 9,962 RSP No. 18 #N/A #N/ACoarse 1 Coarse 2 Coarse 3 Mfg. Fines 233

F-29 Specific Gravity Measurements In order to complete the evaluation of the trial mixes, the specific gravity of the mixes—both the theoretical maximum specific gravity values of loose mix and the bulk specific gravity of the compacted specimens—are measured. Data from specific gravity measurements are entered in worksheet “Specific_Gravity.” In this worksheet, you can either enter raw data from the measurements and have HMA Tools calculate the specific gravity values, or you can just enter the correct specific gravity values without the raw data—this would happen, for instance, if your laboratory has its own forms for recording specific gravity measurements and does not want to use HMA Tools for this purpose. Enter the following data for specific gravity measurements in worksheet “Specific_Gravity:” Trial Mix No. 1 Bulk Specific Gravity—Weight in Water/SSD Method Measurement Specimen 1 Specimen 2 Dry mass in air, g 4,683.0 4,746.3 SSD mass in air, g 4,695.2 4,751.8 Mass in water, g 2,697.0 2,743.7 Theoretical Maximum Specific Gravity—Pyncnometer Method Measurement Specimen 1 Specimen 2 Dry mass in air, g 2,085.1 2,089.9 Mass of pyncnometer filled with water, g 7,573.1 7,648.5 Mass of pyncnometer with mix and water, g 8,812.6 8,891.9 Trial Mixes No. 2 and No. 3 Measurement Trial Mix No. 1 Trial Mix No. 2 Bulk Specific Gravity 2.378 2.367 Theoretical Maximum Specific Gravity 2.462 2.463 Turn to the next page to see what the completed worksheet should look like. On the page after that one is a copy of the worksheet “Trial_Blends,” showing what it will now look like after completing the specific gravity information. 234

F-30 SPECIFIC GRAVITY CALCULATIONS BULK SPECIFIC GRAVITY Weight in Water/SSD Method 1-1 1-2 1-3 2-1 2-2 2-3 3-1 3-2 3-3 Dry mass in air, g, A 4683.0 4746.3 SSD mass in air, g, B 4695.2 4751.8 Mass in water, g, C 2697.0 2743.7 Water absorption, Wt. %, (B-A)/(B-C) x 100% 0.61 0.27 Low absorption or high absorption (> 2%)? Low #N/A #N/A Bulk specific gravity, dry basis, A/(B-C) 2.344 2.364 #N/A #N/A #N/A #N/A #N/A #N/A #N/A Average 2.354 #N/A #N/A Range 0.020 #N/A #N/A Acceptable? (Within d2s Precision) YES #N/A #N/A Weight in Water/Wax/Parafilm Method Dry mass in air, g, A Dry mass in air, coated specimen, g, D Mass in water, coated specimen, g, E Specific gravity of coating, F Bulk specific gravity, dry basis, A/[D-E-(D-A)/F] #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A Average #N/A #N/A #N/A Range #N/A #N/A #N/A Acceptable? (Within d2s Precision) #N/A #N/A #N/A User-Calculated Value Bulk specific gravity, dry basis 2.378 2.367 USE BULK SPECIFIC GRAVITY 2.354 2.378 2.367 COMMENTS MAXIMUM SPECIFIC GRAVITY Weight in Water Method Dry mass in air, g, A Surface-dry mass in air, g, A' (dry-back method for porous aggregate only) Mass of specimen in water, g, C Theor. Max. Sp. Grav., A/(A-C) or A/(A'-C) Range #N/A #N/A #N/A Accpetable? (Within d2s precision) #N/A #N/A #N/A Pyncnometer Method Dry mass in air, g, A 2085.1 2089.9 Surface-dry mass in air, g, A' (dry-back method for porous aggregate only) Mass of pyncnometer filled with water, g, F 7573.1 7648.5 Mass of pync. With mix and water, g, G 8812.6 8891.9 Correction for Thermal Exp. Of Binder, g, H 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Density of water at test temp., Mg/m^3, dw 0.997 0.997 0.997 0.997 0.997 0.997 0.997 0.997 0.997 Theor. Max. Sp. Grav., {A/[(A+F)-(G+H)]} x (dw/0.997) 2.466 2.469 or {A/[(A'+F)-(G+H)]} x (dw/0.997) Range 0.003 #N/A #N/A Accpetable? (Within d2s precision) YES #N/A #N/A User-Calculated Value Theoretical maximum specific gravity 2.462 2.463 USE THEORETICAL MAXIMUM SPECIFIC GRAVITY 2.467 2.462 2.463 Trial 1 Trial 2 Trial 3 235

F-31 SPECIFIC GRAVITY CALCULATIONS (continued from previous page) User-Calculated Value Theoretical maximum specific gravity 2.462 2.463 USE THEORETICAL MAXIMUM SPECIFIC GRAVITY 2.467 2.462 2.463 VOLUMETRIC ANALYSIS Aggregate bulk specific gravity, dry basis 2.645 2.642 2.639 Air void content, % by volume 4.6 3.4 3.9 Asphalt content, % by weight 5.13 5.10 5.10 Aggregate content, % by weight 94.87 94.90 94.90 VMA, % by volume 15.6 14.6 14.9 Vbe, % by volume 11.0 11.2 11.0 Calculated Agg. Eff. Specific Gravity 2.670 2.662 2.664 Calc. Absorbed asphalt, % by Agg. Wt. 0.37 0.30 0.36 Absorbed asphalt, % by total weight 0.35 0.28 0.34 Absorbed asphalt, % by total volume 0.80 0.66 0.79 Effective asphalt, % by total weight 4.78 4.82 4.75 Dust/binder ratio 1.39 1.25 1.13 A useful feature of the “Specific_Gravity” worksheet is that if you use this to enter data from specific gravity measurements, it will flag results that exceed AASHTO d2s single-operator precision limits. In other words, it will warn you if your specific gravity replicate measurements are further apart than what should normally be expected. These warnings appear in rows 16, 28 and 61 for each of three different tests—two different methods for bulk specific gravity measurements and theoretical maximum specific gravity. Which of the two methods for determining bulk specific gravity of HMA specimens is used will normally depend on the absorption of the specimen; the bulk specific gravity of highly absorptive mixtures—those with water absorption values greater than 2.0 percent—should be determined using the wax/parafilm method. HMA Tools will warn you in row 12 if the absorption of the mixture is above 2.0%, meaning that you must use the wax/parafilm method for that mixture. At the bottom of the worksheet is listed the results of a complete volumetric analysis of each of the three trial mixes. These are values calculated from the composition of the mixture and the specific gravity measurements, and are not estimates. These values are carried back to the worksheet “Trial_Mixtures” and will now appear in several places within this worksheet, including the gradation plots. This makes adjusting aggregate gradations to meet volumetric requirements much easier. On The next page the “Trial_Blends” worksheet is shown again, this time as it appears after completing the “Specific_Gravity” worksheet. 236

F-32 TRIAL AGGREGATE BLENDS help appears at lower right INCLUDE MAX. DENSITY GRADATION: X PLOT (X): X x x Material Gsb Gsa Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7 Coarse 1 2.704 2.742 12 12 12 Coarse 2 2.680 2.735 12 12 12 Coarse 3 2.628 2.713 10 18 26 Mfg. Fines 2.666 2.737 36 28 20 #N/A 0.000 0.000 #N/A 0.000 0.000 #N/A 0.000 0.000 #N/A 0.000 0.000 RSP No. 18 2.590 2.624 30 30 30 #N/A 0.000 0.000 #N/A 0.000 0.000 #N/A 0.000 0.000 TOTAL 100 100 100 0 0 0 0 Overall Target VMA, Vol. % Target VMA for Trial Batch, Vol. % 15.0 15.0 15.0 Overal Target Air Voids, Vol. % Target Voids for Trial Batch, Vol. % 4.0 4.0 4.0 Binder Content for Trial Batch, Wt. % 5.13 5.10 5.10 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Specified Dust/Binder Ratio: Estimated Dust/Effective Binder Ratio 1.4 1.3 1.1 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Required New PG Grade for Selected Stockpile Blends (conservative) Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7 High Temperature (Min.) 64.0 64.0 64.0 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Low Temperature/BBR (Max.) -28.0 -28.0 -28.0 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Low Temperature/DT (Max.) #N/A #N/A #N/A #DIV/0! #DIV/0! #DIV/0! #DIV/0! Intermediate Temperature (Max.) 25.0 25.7 25.7 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Select Binder (X) Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 Trial 7 PG 58-28 / Acme Materials X X X / / / BINDER NO 1 1 1 ??? ??? ??? ??? SPECIFIED BINDER GRADE BLENDED GRADE, PG- 64-(22)-22 64-(22)-22 64-(22)-22 #DIV/0! #DIV/0! #DIV/0! #DIV/0! Allowable RAP Content for Binder Grade and Variability Min. RAP for Binder Grade, Wt. % 10.0 10.0 10.0 #N/A #N/A #N/A #N/A Max. RAP for Binder Grade, Wt. % 50.0 50.0 50.0 #N/A #N/A #N/A #N/A Max. RAP for Variability, Wt. % Total RAP Content, Wt. % 29.5 29.5 29.5 #DIV/0! #DIV/0! #DIV/0! #DIV/0! 15.0 4.0 64-(25)-22 0 0.8 to 1.6 0 20 40 60 80 100 0.00 7.00 Particle Size0.45, mm % P as si ng b y W ei gh t Trial, voids/VMA No. 1, 4.6/15.6 No. 2, 3.4/14.6 No. 3, 3.9/14.9 Min., 14.0/ 3.5 Max., 16.0/ 4.5 Max. Dens. 0.075 0.60 2.36 4.75 9.5 12.5 19.0 25.0 37.5 50.0 -20 -15 -10 -5 0 5 10 15 20 0.01 0.10 D ev ia tio n fr om M ax im um D en si ty G ra da tio n coarse 237

F-33 Evaluating and Refining Trial Mixtures After mixing, compacting, and analyzing the volumetric composition of the three trial mixtures, the specification requirements of each should be analyzed. This is best done by reviewing information on the worksheet “Trial_Blends.” But remember, specific gravity testing must first be performed on the trial mixtures and entered into worksheet “Specific_Gravity.” Check the various specification requirements on all there trial mixtures. Which, if any, meets all requirements? If more than one meets all requirements, which seems to best meet the various specifications? Turn to the next page to see a comparison of specification requirements for all three trial mixtures. 238

F-34 The table below summarizes all the various requirements for this HMA mix design. All three trial mixes meet most of the requirements, but mixes 1 and 2 fail the air void requirement of 3.5 to 4.5% (the air void content of mix 1 is too high, while the air void content of mix 2 is slightly low). Therefore, trial mix 3 meets all requirements, and would be the mix to select for moisture resistance testing. In practice when developing a new HMA mix design, many times none of the trial mixes will meet all requirements. In that case, you need to determine which trial mix comes closest to meeting all requirements, and then modify it so that it does meet all requirements. This is a trial-and-error procedure that may require quite a few iterations before a final mix design is developed. Note that the minimum and maximum RAP contents for binder grade—10 and 50%, respectively—are based not on the binder grade analysis, but on practical limits for adding RAP at typical hot mix plants. It is difficult to add less than 10% RAP to a mix accurately, and also difficult to add more than 50% RAP at many plants. For this reason, if the calculated minimum RAP content is less than 10%, HMA Tools will return 10%. Similarly if the calculated maximum RAP content based on binder grade analysis is over 50%, HMA Tools will list the maximum as 50%. Property Specified Value Trial Mix Number Min. Max. 1 2 3 VMA, Vol.% 14.0 16.0 15.6 14.6 14.9 Air voids, Vol.% 3.5 4.5 4.6 3.4 3.9 Blended Binder performance Grade High temperature, °C 64 --- 64 64 64 Low temperature, °C --- −22 −22 −22 −22 Intermediate Temp., °C --- 25 22 22 22 Dust/binder ratio 0.8 1.6 1.4 1.3 1.1 Max. RAP content based on variability analysis,% by total mix weight --- 30 See Below Min. and Max. RAP content based on binder grade analysis 10 50 Actual RAP content See above 29.5 29.5 29.5 CAFF/one face, Wt.% 75 --- 100 100 100 CAFF/two faces, Wt.% --- --- 98 98 98 Flat & elongated particles, Wt.% --- 10 3 3 3 FAA, uncompacted voids, Vol.% 40 --- 47 47 47 Clay content, sand equivalent 40 --- 66 66 66 239

F-35 Moisture Resistance Testing (AASHTO T 283) Just as in Superpave, one of the last steps in the mix design is performing moisture resistance testing following AASHTO T283. In HMA Tools, moisture resistance test data are entered in worksheet “T_283.” This worksheet follows very closely the example data form included in the AASHTO standard method for this test. The worksheet will calculate bulk specific gravity, air voids, indirect tensile strength, and tensile strength ratio once the appropriate data are entered. You must enter theoretical maximum specific gravity data in cell F23 in order to calculate percent air voids. This value can be taken from worksheet “Specific_Gravity,” or it can be calculated separately using the theoretical maximum specific gravity tool that appears at the bottom of this worksheet. Once air void contents are calculated, the “T_283” worksheet will rank the specimens according to their air void content, so they can be split up for conditioned or unconditioned testing. An example of a completed “T 283” worksheet appears on the next page. Note that up to seven sets of moisture resistance testing data can be added in this form—one for each of up to seven trial mixtures. However, usually you will only need to enter data for only one or two trial mixes for a mix design. The large numbers “1” in the left hand margin of the worksheet indicate that this form is for trial mix 1. You need to make certain when entering moisture resistance data in this worksheet that you are entering data in correct location for the trial mix tested. The performance test worksheet “Performance” is set up the same way. 240

F-36 AASHTO T 283 Project: Tutorial Trial Blend Number: 1 Additive: None Additive Dosage: Compaction Method: Gyratory Compaction Effort: 75 Date Tested: 10/30/2009 Tested by: J. Doe 1 2 3 4 5 6 7 8 Diameter, mm (in.) D 150.0 150.0 150.0 150.0 150.0 150.0 Thickness, mm (in.) t 95.2 93.7 99.3 94.5 95.1 98.0 Dry Mass in Air, g A 3852.5 3797.2 4059.6 3825.9 4101.1 3968.2 Saturated, Surface-Dry Mass in Air, g B 3865.9 3812.0 4071.4 3866.1 4119.1 3980.1 Mass in Water, g C 2179.8 2163.8 2290.5 2187.4 2336.7 2245.1 Volume (B - C), cm^3 E 1686.1 1648.2 1780.9 1678.7 1782.4 1735.0 0.0 0.0 Bulk Specific Gravity, (A/E) Gmb 2.285 2.304 2.280 2.279 2.301 2.287 #DIV/0! #DIV/0! Maximum Specific Gravity (Gmm worksheet appears below) Gmm 2.463 % Air Voids [ 100 x (Gmm - Gmb)/Gmm ] Pa 7.2 6.5 7.4 7.5 6.6 7.1 0.0 0.0 Rank 3 6 2 1 5 4 Select for Conditioning (X) x x x Average % Air Voids, Dry Specimens 7.1 Average % Air Voids, Wet Specimens 7.0 Volume of Air Voids (Pa x E/100), cm^3 Va 121.95 106.50 132.67 125.35 117.32 123.88 0.00 0.00 Load, Dry Specimen, N (lbf) Pa 18307 17550 17805 Saturation Time, min 10 10 10 Saturation Vacuum 51 51 50 Vacuum Units (kPa, psi, mm Hg, or in. Hg kPa kPa kPa Thickness after Saturation, mm (in.) t' 94.1 95.3 98.2 SSD Mass after Saturation, g B' 3875.1 3919.5 4055.8 Volume of Absorbed Water (B' - A), cm^3 J' 77.9 93.6 87.6 % Saturation (100 x J' / Va) S' 73.1 74.7 70.7 Load, Wet Specimen, N (lbf) P' 16404 15731 15790 Dry Strength [2000 x P/ pi x t x D)], kPa (psi) S1 816.1 750.1 794.6 Wet Strength [2000 x P/ pi x t x D)], kPa (psi) S2 739.9 700.6 682.4 Visual Moisture Damage (0 = none, 5 = severe) 1 Cracked and/or Broken Aggregate (yes/no) no Tensile Strength Ratio (Average S2 / Average S1) 0.90 Specimen Number: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Help for Worksheet T-283 This worksheet is for recording data for AAHTO T 283: Resistance of Compacted H procedure. Project data is entered in the cells to the right of this help box. Specime worksheet closely follow the data form included in the AASHTO T-283 write-up. A calculation tool for theoretical maximum specific gravity appears at right, as an ai are not carried over into any other part of HMA Tools. Seven separate tables are included in this worksheet--one for each trial batch. You Find the table with the correct trial batch number by paging down through the works worksheet in large black numbers. You don't need to fill out all the tables, only for th 241

F-37 Performance Testing In the Superpave mix design method, there is no performance or “proof” test after completing a volumetric mix design. In the mix design procedure described in this manual, HMA mix designs intended for traffic levels of 3,000,000 ESALs or greater must be evaluated for rut resistance using one of six performance tests: • Asphalt mixture performance test (AMPT), flow number test • AMPT, flow time test • Asphalt pavement analyzer (APA) • Hamburg wheel tracking test • Superpave shear tester, repeated load at constant height (SST/RSCH) test • Indirect tensile strength at high temperature Suggested minimum or maximum values for these tests (or other guidelines) are given in the manual, in Chapter 8. Flexibility is allowed in which test to run, since there are significant data supporting the usefulness of each of these tests, and a number of agencies have already begun to implement performance testing with several of these procedures. Because performance testing of HMA mixtures as part of the mix design process is just beginning, it is strongly recommended that after selecting a performance test to use in their state, highway agencies review the specification values given in the Manual with consideration of their local materials, climate, and traffic levels. It is likely that many highway agencies will modify the performance test requirements given in this manual, so technicians and engineers responsible for developing HMA mix designs should stay informed of the latest standards and specifications issued by their state. Because the mix design in this example is intended for a traffic level of only 800,000 ESALs, no performance test is required. If performance testing were required, this information should be entered in worksheet “Performance” of HMA Tools. This worksheet is very simple, and does not perform any calculations, since the nature of possible performance tests varies widely. As mentioned previously, this worksheet allows you to enter data for up to seven mixtures, in other words, for each of up to seven trial mixes. When entering data in worksheet “Performance” you need to make certain you are entering data in the correct location; the trial mix number is shown in large numbers in the left hand number of the worksheet. The information in worksheet “Performance” is carried over into worksheets “Report” and “Complete_Report” so that the summary report on the selected mixture will include the results of performance testing when required. For engineers and technicians interested in learning more about evaluating the performance of HMA mixtures, Chapter 6 of the Manual covers this topic in detail, and includes useful information on the testing needed to design HMA pavements with the Mechanistic-Empirical Pavement Design Guide. 242

F-38 Printing a Report on a Mix Design Once you have completed a mix design, or if you want to summarize one or more trial mixes, you can use HMA Tools to print out a report. Go to worksheet “Short_Report,” and fill out the date in cell D4, and place “3” in cell D5, meaning you want to generate a report for trial mix No. 3. Then just print out the report, which will look just like the computer screen. Compare your report to the one that appears on the next page. Worksheet “Short_Report” generates a short but fairly complete report on a single selected mix design. You may wish to generate a report on a complete series of tests used in developing a mix design. In that case, use worksheet “Complete_Report” to do you report. This worksheet prints out reports on all trial mixes. 243

F-39 SHORT REPORT ON HMA MIX DESIGN Material Gsb Gsa Wt. % MIXTURE VOLUMETRIC PROPERTIES 2.704 2.742 11.4 2.680 2.735 11.4 Specifications Value 2.628 2.713 24.7 Voids 3.5 to 4.5 3.9 2.666 2.737 19.0 VMA 14 to 16.0 14.9 #N/A #N/A 0.0 Dust/Binder 0.8 to 1.6 1.1 #N/A #N/A 0.0 #N/A #N/A 0.0 Vbe NA 11.0 #N/A #N/A 0.0 VFA NA 73.8 2.590 2.624 28.5 #N/A #N/A 0.0 #N/A #N/A 0.0 #N/A #N/A 0.0 5.10 Required Asphalt Binder Grade: 4.07 Blended Asphalt Binder Grade: Aggregate Blend Effective Specfic Gravity: 2.664 New Asphalt Binder Grade: AGGREGATE GRADATION OTHER AGGREGATE PROPERTIES Sieve Size, mm Min. Max. Blend Value 50.000 100 100 100 75 % Min. 100.0 37.500 100 100 100 0 % Min. 98.0 25.000 100 100 100 10 % Max. 3.0 19.000 100 100 100 #N/A #N/A 12.500 90 100 100 #N/A #N/A 9.500 28 90 88 4.750 28 90 56 2.360 28 58 33 40 % Min. 47.0 1.180 2 58 24 40 % Min. 66.0 0.600 2 58 17 #N/A #DIV/0! 0.300 2 58 12 #N/A #DIV/0! 0.150 2 58 8 0.075 2 10 5.7 MOISTURE RESISTANCE (AASHTO T 283) ESTIMATED MIXTURE DYNAMIC MODULUS, PSI TSR #DIV/0! Temperature, F: Visual Moisture Damage (0 = none, 5 = severe) 0 Freq., Hz 14 40 70 100 130 Cracked and/or Broken Aggregate (yes/no) 0.00 25 2,936,000 2,111,000 920,000 279,500 88,800 10 2,837,000 1,891,000 706,000 193,100 63,200 Additive: 5 2,751,000 1,713,000 565,000 145,000 50,900 Dosage 1 2,508,000 1,275,000 316,000 75,900 36,700 0.5 2,383,000 1,089,000 240,000 59,500 34,300 0.1 2,039,000 699,000 124,000 39,600 32,000 PERFORMANCE TESTING Type of Performance Test: Design Traffic Level (million ESALs): Required Result / Units, Min. / Max.: Test Result / Units Comments: Not specified Surface Course (yes/no): Traffic Level (million ESALs): Ndesign: Compactor Type: Angle Calibration Method: Yes 0.8 75 Not specified 0 0 0 0 0 0 0 #N/A #N/A #N/A RSP No. 18 #N/A #N/A #N/A #N/A Date (mm/dd/yyyy): Select Trial Blend No. 1 through 7 Coarse 2 3 Tutorial J. Doe 12.5 Coarse 3 Project: Tech./Engr.: NMAS (size in mm): Coarse 1 Mfg. Fines CAFF, One Fracture Face, % Flat & Elong., % Specification 64-(22)-22 PG-64-(25)-22Total Asphalt Binder New Asphalt Binder PG-64-(22)-22 Percent Passing: Coarse Aggregate Fine Aggregate FAA, Uncompacted Voids, % 0 CAFF, Two Fractured Faces, % Sand Eq., % 244

F-40 Other Chapters in the Mix Design Manual Congratulations! You have completed the tutorial. This exercise was meant to familiarize technicians and engineers with the most important parts of the Manual, and with the HMA Tools spreadsheet. There are four chapters in the manual that were not covered in this tutorial: Chapter 7. Selection of Asphalt Concrete Mix Type Chapter 10. Design of Gap-Graded HMA Mixtures Chapter 11. Design of Open-Graded Mixtures Chapter 12. Field Adjustments and Quality Assurance of HMA Mixtures Chapter 7 is a discussion of what HMA mix type should be used for a given application. Selection of mix type is usually done by engineers responsible for pavement design, and so most technicians involved in mix design will never have to make this decision. However, there may be some cases where private clients are not sure what type of mix they need and the technician or laboratory engineer will need to help decide the appropriate type of HMA to use for a certain application. In these cases, Chapter 7 will provide all or most of the information to make an appropriate selection. Open-graded and especially gap-graded mixtures are becoming increasingly common on our nation’s highway pavements; if you find yourself designing these types of mixtures, you should carefully read Chapters 10 or 11. Keep in mind that requirements for these mix types tend to vary quite a bit from state to state, so make sure you have your agency’s latest specifications for the type of mix you are designing. Chapter 12 covers information that is needed when taking an HMA mix design from the laboratory to field production. Many technicians and engineers that do mix design work will not be involved directly in this part of the HMA business, but some may find that they become involved in field production. Most HMA mix designs as produced in the laboratory really represent starting points for the final job mix formula used during production. This is because the aggregates in a mix will be changed during processing at the plant—for example, the amount of fines in a plant produced mix will usually be higher than for the identical laboratory mix design. These differences in aggregate gradation will often require adjustments in the mix in order to meet specifications. The second topic covered in Chapter 12 is quality assurance. Again, many technicians and engineers may not have a need for this information, but for those involved in HMA quality assurance, Chapter 12 provides useful information on production variability, control charts, and acceptance plans. 245