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65 APPENDIX B Revised Simple Performance Test System Specification

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66 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 Table of Contents Table of Contents ...................................................................................................................66 1.0 Summary .......................................................................................................................67 2.0 Definitions ......................................................................................................................71 3.0 Test Specimens ...............................................................................................................71 4.0 Simple Performance Test System ...................................................................................72 5.0 Compression Loading Machine ......................................................................................73 6.0 Loading Platens...............................................................................................................74 7.0 Load Measuring System .................................................................................................75 8.0 Deflection Measuring System .........................................................................................75 9.0 Specimen Deformation Measuring System ....................................................................75 10.0 Confining Pressure System ...........................................................................................77 11.0 Environmental Chamber ...............................................................................................78 12.0 Computer Control and Data Acquisition ......................................................................78 13.0 Computations ................................................................................................................88 14.0 Calibration and Verification of Dynamic Performance ................................................95 15.0 Verification of Normal Operation.................................................................................96 16.0 Documentation ..............................................................................................................97 17.0 Warranty .......................................................................................................................97 Annex A. Simple Performance Test System Flow Time Test ..............................................98 Annex B. Simple Performance Test System Flow Number Test..........................................103 Annex C. Simple Performance Test System Dynamic Modulus Test ..................................109 Annex D. Procedure for Developing a Dynamic Modulus Master Curve for Pavement Structural Design Using The Simple Performance Test System. .............115 Annex E. Specification Compliance Test Methods for the Simple Performance Test System .............................................................................126 Annex F. Minimum Testing Program For Comparison of a Non-Standard Specimen Deformation Measuring System to the Standard Specimen Deformation Measuring System......................................................................................................132

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67 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 1.0 Summary 1.1 This specification describes the requirements for a testing system to conduct the following National Cooperative Highway Research Program (NCHRP) Project 9-19 simple performance tests: Test Method For Static Creep/Flow Time of Asphalt Concrete Mixtures in Compression Test Method for Repeated Load Testing of Asphalt Concrete Mixtures in Uniaxial Compression Test Method for Dynamic Modulus of Asphalt Concrete Mixtures for Permanent Deformation Test Method for Dynamic Modulus of Asphalt Concrete Mixtures for Fatigue Cracking Test Methods for each of these tests using the equipment described in this specification are presented in Annexes A, B, and C of this equipment specification. The testing system can also be used in conjunction with AASHTO TP62 to develop a dynamic modulus master curve for pavement structural design using the reduced testing protocol described in Annex D. Note: This equipment specification represents a revision of the equipment requirements contained in NCHRP Report 465 and AASHTO TP62. The requirements of this specification supersede those contained in NCHRP Report 465 and AASHTO TP62. 1.2 The testing system shall be capable of performing three compressive tests on nominal 100 mm (4 in) diameter, 150 mm (6 in) high cylindrical specimens. The tests are briefly described below. 1.3 Flow Time Test. In this test, the specimen is subjected to a constant axial compressive load at a specific test temperature. The test may be conducted with or without confining pressure. The resulting axial strain is measured as a function of time and numerically differentiated to calculate the flow time. The flow time is defined as the time corresponding to the minimum rate of change of axial strain. This is shown schematically in Figure 1. 1.4 Flow Number Test. In this test, the specimen, at a specific test temperature, is subjected to a repeated haversine axial compressive load pulse of 0.1 sec every 1.0 sec. The test may be conducted with or without confining pressure. The resulting permanent axial strains are measured as a function of time and numerically differentiated to calculate the flow number. The flow number is defined as the

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68 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 number of load cycles corresponding to the minimum rate of change of permanent axial strain. This is shown schematically in Figure 2. 0.025 Axial Strain ( ), mm/mm 0.020 0.015 0.010 0.005 0.000 0 100 200 300 400 Time, Sec a. Axial Strain in Flow Time Test. 1.0E-04 8.0E-05 d( )/dt 6.0E-05 4.0E-05 2.0E-05 0.0E+00 0 100 200 300 400 Time, Sec b. Rate of Change of Axial Strain. Figure 1. Schematic of Flow Time Test Data.

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69 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 p), 0.025 Permanent Axial Strain ( 0.020 mm/mm 0.015 0.010 0.005 0.000 0 1000 2000 3000 Load Pulse a. Permanent Axial Strain in Flow Number Test. 1.0E-05 8.0E-06 p)/dt 6.0E-06 4.0E-06 d( 2.0E-06 0.0E+00 0 500 1000 1500 2000 2500 3000 Load Pulse b. Rate of Change of Permanent Axial Strain. Figure 2. Schematic of Flow Number Test Data.

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70 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 1.5 Dynamic Modulus Test. In this test, the specimen, at a specific test temperature, is subjected to controlled sinusoidal (haversine) compressive stress of various frequencies. The applied stresses and resulting axial strains are measured as a function of time and used to calculate the dynamic modulus and phase angle. The dynamic modulus and phase angle are defined by Equations 1 and 2. Figure 3 presents a schematic of the data generated during a typical dynamic modulus test. o E* (1) o Ti (360) (2) Tp Where: E* = dynamic modulus = phase angle, degree o = stress amplitude o = strain amplitude Ti = time lag between stress and strain Tp = period of applied stress PERIOD, TP TIME LAG, TI AXIAL STRAIN LOAD 2O O 0.00 0.05 0.10 0.15 TIME, SEC Figure 3. Schematic of Dynamic Modulus Test Data.

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71 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 2.0 Definitions 2.1 Flow Time. Time corresponding to the minimum rate of change of axial strain during a creep test. 2.2 Flow Number. The number of load cycles corresponding to the minimum rate of change of permanent axial strain during a repeated load test. 2.3 Dynamic Modulus. Ratio of the stress amplitude to the strain amplitude for asphalt concrete subjected to sinusoidal loading (Equation 1). 2.4 Phase Angle. Angle in degrees between a sinusoidally applied stress and the resulting strain in a controlled stress test (Equation 2). 2.5 Resolution. The smallest change of a measurement that can be displayed or recorded by the measuring system. When noise produces a fluctuation in the display or measured value, the resolution shall be one-half of the range of the fluctuation. 2.6 Accuracy. The permissible variation from the correct or true value. 2.7 Error. The value obtained by subtracting the value indicated by a traceable calibration device from the value indicated by the measuring system. 2.8 Confining Pressure. Stress applied to all surfaces in a confined test. 2.9 Deviator Stress. Difference between the total axial stress and the confining pressure in a confined test. 2.10 Dynamic Stress. Sinusoidal deviator stress applied during the Dynamic Modulus Test. 2.11 Dynamic Strain. Sinusoidal axial strain measured during the Dynamic Modulus Test. 3.0 Test Specimens 3.1 Test specimens for the Simple Performance Test System will be cylindrical meeting the following requirements.

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72 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 Item Specification Note Average Diameter 100 mm to 104 mm 1 Specimen Dimensions Standard Deviation of Diameter 0.5 mm 1 Height 147.5 mm to 152.5 mm 2 End Flatness 0.5 mm 3 End Perpendicularity 1.0 mm 4 Notes: 1. Using calipers, measure the diameter at the center and third points of the test specimen along axes that are 90 apart. Record each of the six measurements to the nearest 0.1 mm. Calculate the average and the standard deviation of the six measurements. 2. Measure the height of the test specimen in accordance with Section 6.1.2 of ASTM D 3549. 3. Using a straightedge and feeler gauges, measure the flatness of each end. Place a straight edge across the diameter at three locations approximately 120 apart and measure the maximum departure of the specimen end from the straight edge using tapered end feeler gauges. For each end record the maximum departure along the three locations as the end flatness. 4. Using a combination square and feeler gauges, measure the perpendicularity of each end. At two locations approximately 90 apart, place the blade of the combination square in contact with the specimen along the axis of the cylinder, and the head in contact with the highest point on the end of the cylinder. Measure the distance between the head of the square and the lowest point on the end of the cylinder using tapered end feeler gauges. For each end, record the maximum measurement from the two locations as the end perpendicularity. Note: Test specimens will be fabricated using separate equipment. This information is provided for design of the Simple Performance Test system. 4.0 Simple Performance Test System 4.1 The Simple Performance Test System shall be a complete, fully integrated testing system meeting the requirements of these specifications and having the capability to perform the Flow Time, Flow Number, and Dynamic Modulus tests described in Annexes A, B, and C and AASHTO TP62. 4.2 Annex E summarizes the methods that will be used to verify that the Simple Performance Test System complies with the requirements of this specification. 4.3 The Simple Performance Test System shall include the following components: 1. Compression loading machine. 2. Loading platens. 3. Load measuring system. 4. Deflection measuring system. 5. Specimen deformation measuring system.

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73 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 6. Confining pressure system. 7. Environmental chamber. 8. Computer control and data acquisition system. 4.4 The load frame, environmental chamber, and computer control system for the Simple Performance Test System shall occupy a foot-print no greater than 1.5 m (5 ft) by 1.5 m (5 ft) with a maximum height of 1.8 m (6 ft). A suitable frame, bench or cart shall be provided so that the bottom of the test specimen, and the computer keyboard and display are approximately 90 cm (36 in) above the floor. 4.5 The load frame, environmental chamber and computer control system for the Simple Performance Test System shall operate on single phase 115 or 230 V AC 60 Hz electrical power. 4.6 If a hydraulic power supply is required, it shall be air-cooled occupying a foot-print no larger than 1 m (3 ft) by 1.5 m (5 ft). The noise level 2 m (6.5 ft) from the hydraulic power supply shall not exceed 70 dB. The hydraulic power supply shall operate on single phase 115 of 230 V AC 60 Hz electrical power. 4.7 When disassembled, the width of any single component shall not exceed 76 cm (30 in). 4.8 Air supply requirements shall not exceed 0.005 m3/s (10.6 ft3/min) at 850 kPa (125 psi). 4.9 The Simple Performance Test System shall include appropriate limit and overload protection. 4.10 An emergency stop shall be mounted at an easily accessible point on the system. 5.0 Compression Loading Machine 5.1 The machine shall have closed-loop load control with the capability of applying constant, ramp, sinusoidal, and pulse loads. The requirements for each of the simple performance tests are listed below. Test Type of Loading Capacity Rate Flow Time Ramp, constant 10 kN (2.25 kips) 0.5 sec ramp Flow Number Ramp, constant, pulse 8 kN (1.80 kips) 10 Hz pulse with 0.9 sec dwell Dynamic Modulus Ramp, constant, 13.5 kN (3.0 kips) 0.01 to 25 Hz sinusoidal

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74 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 5.2 For ramp and constant loads, the load shall be maintained within +/- 2 percent of the desired load. 5.3 For sinusoidal loads, the standard error of the applied load shall be less than 5 percent. The standard error of the applied load is a measure of the difference between the measured load data, and the best fit sinusoid. The standard error of the load is defined in Equation 3. n 2 xi ^i x i 1 100% se( P) n 4 ^o x (3) Where: se(P) = Standard error of the applied load xi = Measured load at point i ^i x = Predicted load at point i from the best fit sinusoid, See Equation 16 ^o x = Amplitude of the best fit sinusoid n = Total number of data points collected during test. 5.4 For pulse loads, the peak of the load pulse shall be within +/- 2 percent of the specified value and the standard error of the applied load during the sinusoidal pulse shall be less than 10 percent. 5.5 For the Flow Time and Flow Number Tests, the loading platens shall remain parallel during loading. For the Dynamic Modulus Test, the load shall be applied to the specimen through a ball or swivel joint. 6.0 Loading Platens 6.1 The loading platens shall be fabricated from aluminum and have a Brinell Hardness Number HBS 10/500 of 95 or greater. 6.2 The loading platens shall be at least 25 mm (1 in) thick. The diameter of the loading platens shall not be less than 105 mm (4.125 in) nor greater than 108 mm (4.25 in). 6.3 The loading platens shall not depart from a plane by more than 0.0125 mm (0.0005 in) across any diameter.

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75 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 7.0 Load Measuring System 7.1 The Simple Performance Test System shall include an electronic load measuring system with full scale range equal to or greater than the stall force for the actuator of the compression loading machine. 7.2 The load measuring system shall have an error equal to or less than +/- 1 percent for loads ranging from 0.12 kN (25 lb) to 13.5 kN (3.0 kips) when verified in accordance with ASTM E4. 7.3 The resolution of the load measuring system shall comply with the requirements of ASTM E4. 8.0 Deflection Measuring System 8.1 The Simple Performance Test System shall include a electronic deflection measuring system that measures the movement of the loading actuator for use in the Flow Time and Flow Number Tests 8.2 The deflection measuring system shall have a range of at least 12 mm (0.5 in). 8.3 The deflection measuring system shall have a resolution equal to or better than 0.0025 mm (0.0001 in). 8.4 The deflection measuring system shall have an error equal to or less than 0.03 mm (0.001 in) over the 12 mm range when verified in accordance with ASTM D 6027. 8.5 The deflection measuring system shall be designed to minimize errors due to compliance and/or bending of the loading mechanism. These errors shall be less than 0.25 mm (0.01 in) at 8 kN (1.8 kips) load. 9.0 Specimen Deformation Measuring System 9.1 The Simple Performance Test System shall include a glued gauge point system for measuring deformations on the specimen over a gauge length of 70 mm (2.76 in) 1 mm (0.04 in) at the middle of the specimen. This system will be used in the Dynamic Modulus Test, and shall include at least two transducers spaced equally around the circumference of the specimen.

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127 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 Table E1. Summary of Specification Compliance Tests. Item Section Method Assembled Size 4.4 and Measure 4.6 Specimen and Display Height 4.4 Measure Component Size 4.7 Measure Electrical Requirements 4.5 and Documentation and trial 4.6 Air Supply Requirements 4.8 Documentation and trial Limit Protection 4.9 Documentation and trial Emergency Stop 4.10 Documentation, visual inspection, trial Loading Machine Capacity 5.1 Independent force verification (See verification procedures below) Load Control Capability 5.2 Trial tests on asphalt specimens and manufacturer through provided dynamic verification device. 5.4 Platen Configuration 5.5 Visual Platen Hardness 6.1 Test ASTM E10 Platen Dimensions 6.2 Measure Platen Smoothness 6.3 Measure Load Cell Range 7.1 Load cell data plate Load Accuracy 7.2 Independent force verification (See verification procedures below) Load Resolution 7.3 Independent force verification (See verification procedures below) Configuration of Deflection 8.1 Visual Measuring System Transducer Range 8.2 Independent deflection verification (See verification procedures below) Transducer Resolution 8.3 Independent deflection verification (See verification procedures below) Transducer Accuracy 8.4 Independent deflection verification (See verification procedures below) Load Mechanism Compliance 8.5 Measure on steel specimens with various degrees and Bending of lack of parallelism Configuration of Specimen 9.1 Visual Deformation Measuring System Gauge Length of Specimen 9.1 Measure Deformation Measuring System Transducer Range 9.2 Independent deflection verification (See verification procedures below)

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128 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 Table E1. Summary of Specification Compliance Tests (Continued). Item Section Method Transducer Resolution 9.3 Independent deflection verification (See verification procedures below) Transducer Accuracy 9.4 Independent deflection verification (See verification procedures below) Specimen Deformation 9.5 Trial System Complexity Confining Pressure Range 10.1 and Independent pressure verification (See verification 10.5 procedures below) Confining Pressure Control 10.2 Trial tests on asphalt specimens Confining Pressure System 10.3 and Visual Configuration 10.4 Confining Pressure Resolution 10.5 Independent pressure verification (See verification and Accuracy procedures below) Temperature Sensor 10.6 and Independent temperature verification (See 11.4 verification procedures below) Specimen Installation and 9.5, 10.7 Trial Equilibration Time and 11.3 Environmental Chamber 11.1 Independent temperature verification (See Range and Control verification procedures below) Control System and Software 12 Trial Data Analysis 13 Independent computations on trial test Initial Calibration and 14 Certification and independent verification Dynamic Performance Verification Calibration Mode 14.6 Trial Verification of Normal 15 Review Operation Procedures and Equipment On-line Documentation 16.1 Trial Reference Manual 16.2 Review

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129 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 INDEPENDENT VERIFICATION PROCEDURES FOR SIMPLE PERFORMANCE TESTING MACHINE 1.0 General 1.1 The testing machine shall be verified as a system with the load, deflection, specimen deformation, confining pressure, and temperature measuring systems in place and operating as in actual use. 1.2 System verification is invalid if the devices are removed and checked independently of the testing machine. 2.0 Load Measuring System Static Verification 2.1 Perform load measuring system verification in accordance with ASTM E-4. 2.2 All calibration load cells used for the load calibration shall be certified to ASTM E-74 and shall not be used below their Class A loading limits. 2.3 When performing the load verification, apply at least two verification runs of at least 5 loads throughout the range selected. 2.4 If the initial verification loads are within +/- 1% of reading, these can be applied as the "As found" values and the second set of verification forces can be used as the final values. Record return to zero values for each set of verification loads. 2.5 If the initial verification loads are found out of tolerance, calibration adjustments shall be made according to manufacturers specifications until the values are established within the ASTM E-4 recommendations. Two applications of verification loads shall then be applied to determine the acceptance criteria for repeatability according to ASTM E-4. 2.6 At no time will correction factors be utilized to corrected values that do not meet the accuracy requirements of ASTM E-4. 3.0 Deflection and Specimen Deformation Measuring System Static Verification 3.1 Perform verification of the deflection and specimen deformation measuring systems in accordance with ASTM D 6027 Test Method B. 3.2 The micrometer used shall conform to the requirements of ASTM E-83.

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130 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 3.3 When performing verification of the deflection and strain measuring system, each transducer and associated electronics must be verified individually throughout it's intended range of use. 3.4 Mount the appropriate transducer in the micrometer stand and align it to prevent errors caused by angular application of measurements. 3.5 Apply at least 5 verification measurements to the transducer throughout it's range. Re-zero and repeat the verification measurements to determine repeatability. 3.6 If the readings of the first verification do not meet the specified error tolerance, perform calibration adjustments according to manufacturer's specifications and repeat the applications of measurement to satisfy the error tolerances. 4.0 Confining Pressure Measuring System Verification 4.1 Perform verification of the confining pressure measuring system in accordance with ASTM D-5720. 4.2 All calibrated pressure standards shall meet the requirements of ASTM D-5720. 4.3 Attach the pressure transducer to the pressure standardizing device. 4.4 Apply at least 5 verification pressures to the device throughout it's range recording each value. Determine if the verification readings fall within +/- 1 % of the value applied. 4.5 If the readings are within tolerance, apply a second set of readings to determine repeatability. Record the return to zero values for each set of verification pressures. 4.6 If readings are beyond tolerance, adjust the device according to manufacturer's specifications and repeat the dual applications of pressure as described above to complete verification. 5.0 Temperature Measuring System Verification 5.1 Verification of the temperature measuring system will be performed using a using a NIST traceable reference thermal detector that is readable and accurate to 0.1 oC. 5.2 A rubber band or O-ring will be used to fasten the reference thermal detector to the system temperature sensor.

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131 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 5.3 Comparisons of the temperature from the reference thermal detector and the system temperature will be made at 6 temperatures over the operating range of the environmental chamber. 5.4 Once equilibrium is obtained at each temperature setting, record the temperature of the reference thermal detector and the system temperature sensor. 5.5 Also check stability of the environmental chamber by noting the maximum and minimum temperatures during cycling at the set temperature. 6.0 Dynamic Performance Verification 6.1 The verification of the dynamic performance of the equipment will be performed after static verification of the system. 6.2 The dynamic performance verification will be performed using the verification device provided with the system by the manufacturer. 6.3 First, the verification device will be loaded statically to obtain the static relationship between force and displacement. This relationship will be compared to that provided by the manufacturer in the system documentation. 6.4 The verification device will then be used to simulate dynamic modulus test conditions. Load and displacement data will be collected on the verification device using loads of 0.5, 4.5, 8.5, and 12.5 kN (0.1, 1.0, 1.9, and 2.8 kips) at frequencies of 0.1, 1, and 10 Hz. The peak load and displacements will be determined and plotted along with the static data. The data shall plot within +/- 2 percent of the static force displacement relationship. 6.5 The verification device will also be used to check the phase difference between the load and specimen deformation measuring system. The phase difference shall be less than 1 degree.

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132 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 Annex F Minimum Testing Program For Comparison of a Non-Standard Specimen Deformation Measuring System to the Standard Specimen Deformation Measuring System

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133 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 1.0 Summary 1.1 This Annex describes the minimum testing, analysis, and reporting required to demonstrate that a nonstandard specimen deformation measuring system produces the same dynamic modulus and phase angle results as the standard glued gauge point system specified in Section 9.0 of the these specifications. 1.2 The basic approach is to collect dynamic modulus and phase angle data on a single mixture using the simple performance test system with the standard glued gauge point system and the proposed alternative. Standard statistical hypothesis tests are then performed on the resulting data to verify that there is no difference in the mean and variance of the dynamic modulus and phase angles measured with the two systems. 1.3 To provide data over a wide range of modulus and phase angles, the testing will be performed for the conditions listed in Table F-1. Table F-1. Testing Conditions. Temperature, C ( F) Confinement, kPa (psi) Frequencies, Hz 25 (77) Unconfined 10, 1, and 0.1 45 (113) Unconfined 10, 1, and 0.1 45 (113) 140 (20 psi) 10, 1, and 0.1 1.4 Tests on twelve independent specimens will be performed with each specimen deformation measuring system. Thus a total of 24 specimens will be fabricated and tested. 2.0 Test Specimens 2.1 The testing shall be performed on simple performance test specimens meeting the dimensional tolerances of Section 3.0 of these specifications. 2.2 Use a coarse-graded 19.0 mm nominal maximum aggregate size mixture with a PG 64-22 binder. The mixture shall meet the requirements of AASHTO MP2 for a surface course with a design traffic level of 10 to 30 million ESALs. The percent passing the 2.36 mm sieve shall be less than 35 percent. Prepare test specimens at the optimum asphalt content determined in accordance with AASHTO PP28 for a traffic level of 3 to <30 million ESALs. Mixtures shall be short term oven aged for 2 hours at the compaction temperature in accordance with AASHTO R30. 2.3 Prepare 24 test specimens within the air void content range of 3.5 to 4.5 percent. Rank the test specimens based on air void content. Group the test specimens into two subsets such that the average and standard deviation of the air void contents are approximately equal.

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134 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 3.0 Dynamic Modulus Testing 3.1 Perform the dynamic modulus testing with the Simple Performance Test System in accordance with Annex C of these specifications. Repeat tests as needed to ensure that the data quality indicators are within their allowable ranges. 3.2 Perform the testing in blocks of three specimens in the order listed in Table F-2. Plan the testing such that all testing in a block will be completed on the same day. Table F-2. Block Order Testing. Block Temperature, Confinement, Specimen C ( F) kPa (psi) Deformation System 1 25 (77) 0 Standard Proposed 2 25 (77) 0 Standard Proposed 3 25 (77) 0 Standard Proposed 4 25 (77) 0 Standard Proposed 5 45 (113) 140 (20) Standard Proposed 6 45 (113) 140 (20) Standard Proposed 7 45 (113) 140 (20) Standard Proposed 8 45 (113) 140 (20) Standard Proposed 9 45 (113) 0 Standard Proposed 10 45 (113) 0 Standard Proposed 11 45 (113) 0 Standard Proposed 12 45 (113) 0 Standard Proposed

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135 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 4.0 Data Analysis 4.1 For each combination of device, temperature, confining pressure, and frequency, prepare summary tables listing the measured dynamic modulus and phase angles, and the data quality indicators. A total of 18 summary tables, 9 for each measuring system will be prepared. Each of these summary tables will represent a specific combination of temperature, confining pressure, and frequency of loading. 4.2 For each summary table, compute the mean and variance of the dynamic modulus and phase angle measurements using Equations F-1 and F-2. 12 yi i 1 y (F-1) 12 12 ( yi y)2 s2 i 1 (F-2) 11 where: y = sample mean s2 = sample variance yi = measured values 5.0 Statistical Hypothesis Testing 5.1 For each combination of temperature, confining pressure, and frequency of loading test the equality of variances between the standard specimen deformation system and the proposed specimen deformation measuring system using the F-test described below. In the description below, the subscript s refers to the standard system and the subscript p refers to the proposed system. Null Hypothesis: 2 2 Variance of proposed system equals that of standard system, p s Alternative Hypothesis: 2 2 Variance of proposed system is greater than that of standard system, p s Test Statistic: 2 sp F 2 ss

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136 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 where sp2 = computed sample variance for the proposed system ss2 = computed sample variance for the standard system Region of Rejection: For the sample sizes specified, the test statistic must be less than 2.82 to conclude that the variances are equal. 5.2 Summarize the resulting test statistics for dynamic modulus and phase angle. 5.3 If the results conclude the variance is greater for the proposed measuring for any of the combinations of temperature, confinement, and loading frequency tested, then the proposed measuring system is unacceptable. 5.4 For combinations of temperature, confinement, and loading frequency where equality of variances is confirmed by the hypothesis test in Item 5.1, test the equality of means between the standard specimen deformation system and the proposed specimen deformation measuring system using the t-test described below. In the description below, the subscript s refers to the standard system and the subscript p refers to the proposed system. Null Hypothesis: 2 2 Mean from the proposed system equals that from the standard system, p s Alternative Hypothesis: Mean from the proposed system is not equal to that from the standard system, 2 2 p s Test Statistic: yp ys t n 6 where: 2 2 sp ss s 2 y p = computed sample mean from the proposed system y s = computed sample mean from the standard system

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137 NCHRP 9-29 Equipment Specification for the Simple Performance Test System Version 2.0 March 26, 2004 sp2 = computed sample variance for the proposed system ss2 = computed sample variance for the standard system Region of Rejection: For the sample sizes specified, the absolute value of the test statistic must be less than 2.07 to conclude that the means are equal. 5.5 Summarize the resulting test statistics for dynamic modulus and phase angle. 5.6 If the results conclude the means are not equal for any of the combinations of temperature, confinement, and loading frequency tested, then the proposed measuring system is unacceptable. 6.0 Report 6.1 Design data for the mixture used in the evaluation. 6.2 Air void contents for individual specimens and the average and standard deviations of the air void contents for the two subsets. 6.3 Tabular chronological summary of the block testing showing starting date and time and completion date and time for each block. 6.4 Summary tables of dynamic modulus, phase angle, and data quality indicators for each combination of temperature, confining pressure, and loading frequency for the two measuring systems. 6.5 Summary tables of the mean and variance of the dynamic modulus and phase angle for each combination of temperature, confining pressure, and loading frequency for the two measuring systems. 6.6 Summary tables of the hypothesis tests for the variance and mean of the dynamic modulus and phase angle for each combination of temperature, confining pressure, and loading frequency. 6.7 Conclusions concerning the acceptability of the proposed measuring system.