Comparison of 9.5 mm SuperPave and Marshall Wearing I Mixes in ...

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7developed and implemented by state and federal agencies. This review focuses on the Marshalland Superpave methods since they are currently used by the WVDOH.2.2.1 Overview of the Marshall MethodBruce Marshall developed the earliest version of the Marshall mix design method at theMississippi Highway Department in 1939. The Marshall procedure uses a drop hammer tocompact samples and the stability and flow are tested in a confined compression mold. Inaddition, the volumetric characteristics of the mix are evaluated. In 1943, the Corps ofEngineers Waterways Experiment Station began a study to develop a portable apparatus fordesigning and testing asphalt mixtures for airfield pavements. The Corps began experimentingwith Marshall’s apparatus and developed a series of laboratory and field experiments. Mixtureswere designed in the lab using a variety of compactive efforts to produce lab densities that weresimilar to those achieved in the field under construction and aircraft loads. Laboratory methodsincluded different drop hammer weights, combinations of numbers of blows per side,compactor foot designs and mold base shapes and materials (Roberts, 1996).The main goal of the Corps study was to adopt a sample preparation procedure that wouldinvolve minimum effort and time while providing a basis for selecting the "optimum" asphaltcontent. It was also desirable to develop a method that was portable and could be taken to thefield for quality control tests. Based on the results of this study, a 10-pound hammer with a 37/8 inch diameter foot was selected and a compaction effort of 50 blows per side of thespecimen was selected. It was also determined that two major variables stood out in the designand performance of HMA: asphalt content and density of the mix.During the late 1940s and early 1950s, aircraft size, weight and tire pressure increased. Thiscalled for an increase in the required number of blows per side from 50 to 75. The initialstability requirement of 500 pounds minimum was raised to 1000 pounds and then to 1800pounds to help limit rutting potential of the mixtures. This rutting was primarily seen inmixtures that contained high amounts of natural sand aggregates. These standards wereadopted for the construction of high traffic volume highways, such as interstates.Detailed procedures for Marshall mix design can be found in Roberts, et al, (1996) and theapplicable test standard for the Marshall test is AASHTO T 245-97. West Virginia has publishedspecifications for using the Marshall method for pavement design in the state (WVDOH, 2000),Guide to Designing Hot-Mix Asphalt Using the Marshall Design Method, MP 401.02.22.The Marshall mix design procedure begins with acceptance tests performed on the aggregatesand asphalt cement. After these tests, the procedure presented in ASTM D1559: Resistance toPlastic Flow of Bituminous Mixtures Using the Marshall Apparatus is performed on the mix. Themajor steps involved in performing a mixture are:1. aggregate acceptance tests,
82. determine aggregate stockpile blend meeting specifications,3. specimen preparation and evaluation of bulk specific gravity,4. evaluation of theoretical maximum specific gravity,5. stability and flow tests,6. volumetric analysis, and7. selection of optimum asphalt content.The aggregate acceptance tests ensure the aggregates are suitable for asphalt concrete. TheWVDOH specifications requirements are given in Table 2.1 (WVDOH, 1996).
Page 1 and 2: COMPARISON OF 9.5 MM SUPERPAVE ANDM
Page 3 and 4: iNOTICEThe contents of this report
Page 5 and 6: iiiasphalt concrete wearing courses
Page 7 and 8: vMixing Procedure 78Appendix B Fine
Page 9 and 10: viiTable C-7 Marshall Medium 13% NS
Page 13 and 14: 4Table 1.1 Mix Design Types in Expe
Page 15: 6CHAPTER 2 LITERATURE REVIEW2.1 INT
Page 19 and 20: 10SieveAllowable PercentPassing Sie
Page 21 and 22: 12Stability is recorded as the maxi
Page 23 and 24: 14The WVDOH procedure for determini
Page 25 and 26: 16sieve. This is somewhat different
Page 27 and 28: 18G sb = bulk specific gravity of a
Page 29 and 30: 20theoretical gravity at the initia
Page 31 and 32: 22D/B est = adjusted dust to binder
Page 33 and 34: 24P b,est - 0.5%,P b,est ,P b,est +
Page 35 and 36: Percent Passing261009080Superpave U
Page 37 and 38: 28Table 2.6 WVDOH Marshall and Supe
Page 39 and 40: 30Table 2.9 Habib Marshall Analysis
Page 41 and 42: 32theoretically correct in that the
Page 43 and 44: 34the machine. This variability was
Page 45 and 46: 36CHAPTER 3 EQUIPMENT3.1 INTRODUCTI
Page 47 and 48: 38Hose PressureWheel Load100 psi100
Page 49 and 50: 40mouth. This jar rests on a holder
Page 51 and 52: problematic, as the saturated surfa
Page 53 and 54: 44Mechanical Laboratory Sieve. Afte
Page 55 and 56: Percent Passing4610090100% Limeston
Page 57 and 58: 48Maximum specific gravity is a req
Page 59 and 60: 50gradation. This allowed for direc
Page 61 and 62: Percent Passing521009080Light 100%
Page 63 and 64: 54percentage of aggregate from the
Page 65 and 66: 56Table 5.4 Summary of Volumetric a
Page 67 and 68:
58Table 5.5 Calculated and Adjusted
Page 69 and 70:
60Table 5.6 Results of APA TestsAir
Page 71 and 72:
62exhibit lower rut depths than any
Page 73 and 74:
design had significantly more rutti
Page 75 and 76:
66SP L 100LS SP L 64NS -10.335 2.77
Page 77 and 78:
68percent air voids and percent lim
Page 79 and 80:
Air Voids (%)Uncompacted Voids (%)7
Page 81 and 82:
72than the Marshall mixes. Table 6.
Page 83 and 84:
Voids in the Mineral Aggregate. As
Page 85 and 86:
76REFERENCESAmerican Association of
Page 87 and 88:
78APPENDIX A BUCKET MIXER INSTRUCTI
Page 89 and 90:
80APPENDIX B FINE AGGREGATE ANGULAR
Page 91 and 92:
82Table B-3 Uncompacted Void Conten
Page 93 and 94:
84AGGREGATE DESIGN DATATable C-1 St
Page 95 and 96:
86Table C-3 Computed Blend Gradatio
Page 97 and 98:
88Table C-7 Marshall Medium 13% NS
Page 99 and 100:
90%G mm%AC VMA VTM VFA @ N ini @N d
Page 101 and 102:
92Table C-14 Superpave Light 64% NS
Page 103:
946 2979.3 1696.7 2988.1 2.307 7.09
Page 106 and 107:
971 2912.7 1620.8 2917.9 2.246 7.65
Page 108 and 109:
992 8.40 10.80 7.402 7.90 9.90 7.80
Page 110 and 111:
1011 9.50 6.90 11.502 9.79 7.15 10.
Page 112 and 113:
1032 8.55 5.20 5.95L R RDate Tested
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