Page 54 - Lecture Notes DCC3113
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b.      Complete the Marshall form below and determine the optimum bitumen content of the mix design

                                                                                                                                     Stability   Flow
                                  Weight (g)              Specific Gravity       Volume                 Voids (%)                                      Stiffness
                      %                            Bulk                                                                                (kN)      (mm)
                   Bitumen                       Volume                                                                   Refer
                    Spec.   Saturated                3     Bulk   Max.                           Mineral   Filled   Total   Table        CORR
           Sample.   No     Surface   Air   Water   (cm )   (Density)  Theory   Bitumen  Aggregate  Voids   Agg.   Bitumen   Mix   CORR   MEAS   (Stability)
             No               Dry                                                                (%VMA)   (%VFB)   (%VIM)   Factor
                                                    F       G       H       I       J       K      L       M       N        O      P       Q      R       S
                      B       C       D      E                            B X G   (100-B)G   100-I-               100-    CORR
                                                  (C-E)    D/F      *                             100-J   100(I/L)                       P X O           Q/R
                                                                          SG BIT   SG AG    J                    (100G/H)  FACTOR
                     4.5     1200.8   1195.3  685.9                                                                               1161           3.27

                             1196.4   1193.7  685.9                                                                               1100           3.17
                             1195.7   1192.7  685.4                                                                               1150           3.26
             AVG                                                                                                                                  3.2
                     5.00    1197.9   1194.7  690.7                                                                               1191           3.70

                             1195.8   1192.7  690.2                                                                               1163           3.71
                             1200.5   1197.1  692.4                                                                               1151           3.83
             AVG                                                                                                                                  3.7
                     5.50    1202.8   1199.9  695.2                                                                               1321           4.30

                             1180.3   1176.4  682.7                                                                               1298           4.29
                             1178.6   1174.8  681.2                                                                               1239           3.93
             AVG                                                                                                                                  4.2
                     6.00    1185.0   1182.3  685.8                                                                               1163           4.63

                             1196.0   1191.5  690.6                                                                               1135           4.72
                             1188.8   1184.0  685.6                                                                               1111           4.69
             AVG                                                                                                                                  4.7
                     6.50    1172.7   1168.2  675.9                                                                               870            5.31

                             1185.6   1180.8  685.6                                                                               870            5.48
                             1178.9   1172.4  679.6                                                                               919            5.69
             AVG                                                                                                                                  5.5

              REMARKS
               *  Calculation for Max. Theoretical Specific gravity (Column H)   =   100 / [  ( % By Weight of Bitumen  / SG BIT )   +  ( % By Weight of Combined Aggregate  /  SG AG )  ]
              SG BIT               =      1.02                         Mixing Temperature           =      145°C to 155°C
              SG AG                =      2.668                        Compacting Temperature       =      135°C
              Pen. Grade Bitumen   =      80/100 PEN                   Test Temperature             =      60°C for 45 minutes
              Density Asphalt Mixture  =      Bulk S.G x 1000 kg/cu.m      Density Asphalt Mixture     =      Bulk S.G x 1000 kg/cu.m
              Mixing Temperature   =      145°C to 155°C
              SG AG                =      2.668                        Compacting Temperature       =      135°C
              Pen. Grade Bitumen   =      80/100 PEN                   Test Temperature             =      60°C for 45 minutes

                                                                                   49                                   % By Weight of Combined Aggregate  =  100 - B
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