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Mq <br /> 330-6.2 Continuous Mixing : Introduce the dried aggregates and mineral filler (if <br /> required) , prepared as specified and proportioned to meet the verified mix design, into the mixer <br /> in synchronization with the accurate feeding of the hot asphalt binder. Mix sufficiently to <br /> produce a thoroughly and uniformly coated mixture . <br /> 330-6.3 Mix Temperature : Heat and combine the ingredients of the mix in such a <br /> manner as to produce a mixture with a temperature , when discharged from the pugmill or surge <br /> bin, which is within the master range as defined below . <br /> Determine the temperature of the completed mixture using a quick-reading <br /> thermometer through a hole in the side of the loaded truck immediately after loading . Locate <br /> 1 /4 inch hole on both sides of the truck body within the middle third of the length of the body, <br /> and at a distance from 6 to 10 inches above the surface supporting the mixture . If a truck body <br /> already has a hole located in the general vicinity of the specified location, use this hole . At the <br /> Engineer ' s discretion, the Contractor may take the temperature of the load over the top of the <br /> truck in lieu of using the hole in the side of the truck. <br /> The normal frequency for taking asphalt mix temperatures will be for each day, <br /> for each design mix on the first five loads and one out of every five loads thereafter. Take the <br /> temperature of the asphalt mix at the plant and at the roadway before the mix is placed at the <br /> normal frequency . Record the temperature on the front of the respective delivery ticket. The <br /> Engineer shall review the plant and roadway temperature readings and may take additional <br /> temperature measurements at any time . <br /> The master range for all mix designs will be the target mix temperature from the <br /> mix design ±30°F . There are two master ranges ; one at the asphalt plant (mixing temperature <br /> from the mix design ±30°F) and one at the roadway ( compaction temperature from the mix <br /> design ±30°F) . Reject any load or portion of a load of asphalt mix at the plant with a temperature <br /> outside of this master range . Reject any load or portion of a load of asphalt mix at the roadway <br /> with a temperature outside of this master range . The Engineer will be immediately notified of the <br /> rejection. <br /> If any single load at the plant or at the roadway is within the master range but <br /> differs from the target mix temperature by more than ±25 °F or if the average difference of the <br /> temperature measurements from the target mix temperature for five loads exceeds ± 15°F, the <br /> temperature of every load will be monitored until the temperature falls within the specified <br /> tolerance range in Table 3304 ; at this time the normal frequency may be resumed. <br /> Table 3304 <br /> Temperature Tolerance From Verified Mix Design <br /> Any Single Measurement ±25 °F <br /> Average of Any Five Consecutive ± 15 °F <br /> Measurements <br /> 330-6 .4 Maximum Period of Storage : Allow the maximum time that any mix maybe <br /> kept in a hot storage or surge bin to be 72 hours . <br /> 330-6 . 5 Contractor ' s Responsibility for Mixture Requirements : Produce a <br /> homogeneous mixture , free from moisture and with no segregated materials , that meets all <br /> specification requirements . Also apply these requirements to all mixes produced by the drum <br /> mixer process and all mixes processed through a hot storage or surge bin , both before and after <br /> storage . <br /> - 71 - <br /> FPID ( S ) : 423186 - 1 - 58 -01 <br />