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22 analyses of emissions and degradation potential of the sources, and modifiers as well as a few more unique modifi- 14 binders using the SEP test. Part 2 of the testing plan included cations systems. The list of binders with their reported grades, conducting the series of mixture tests with the 14 binders. crude source, and modification systems is shown in Table 5. Selection of the best method for determining mixing and Throughout this report, data for modified binders are iden- compaction temperatures would be based on how well the tified with shaded rows in tables. Also shown in Table 5 are temperatures predicted using the candidate methods from the recommended mixing and compaction temperatures that Part 1 correlated with the temperatures needed for good coat- the producers have provided to their customers. Inconsisten- ing, workability, and compaction as determined with the cies in the recommended temperatures are apparent. Some mixture tests in Part 2. Analysis of the SEP results and the suppliers recommend a single temperature, whereas others change in binder properties before and after the SEP test were give a range of temperatures as wide as 18F (10C). Also, expected to provide information to be used for establishing Binders B and C are different PG, but have the same exact rec- maximum mixing temperatures so that emissions and/or ommended mixing and compaction temperatures. Binders G binder degradation would not be a problem. Indirect tensile and H, which are both PG 76-22, have recommended mix- mixture tests also would be used to assess the need for upper ing temperatures that differ by at least 10F (6C). limits for mixing temperatures. A set of four different binders were selected for valida- A small validation experiment was planned using a set of tion testing of the method selected for establishing mixing four new binders with a range of grades and modification and compaction temperatures. The validation binders set is types. The validation testing of the binders would include shown in Table 6. testing of the binders with the selected candidate method and performing mix coating tests, workability tests, and com- Organization of the Test Plan paction tests to see whether the predicted mixing and com- paction temperatures provided reasonable results. As previously noted, the overall testing plan was divided into two parts. The first part dealt with testing binders and the sec- ond part involved testing those binders in aggregate mixtures. Materials The mixture tests included in the experimental plan were not The experimental plan included 14 different binders that candidate procedures for establishing mixing and compaction represent a range of commonly used U.S. binder grades, crude temperatures. They were used in the experimental plan to eval- Table 5. Binders included in the research. Producer's Producer's Producer's Recommended Recommended Binder Reported Mixing Compaction Modification I.D. Binder Grade Temperatures Temperatures Type Crude Source B PG 64-40 302-320 284-311 SBS Canada C PG 70-34 302-320 284-311 SBS Canada Alaskan Slope D PG 58-28 295-309 275-284 None /Canada E PG 58-34 293-308 273-284 Air Blown Canada F PG 64-22 315 295 None North Sea G PG 76-22 335 315 SBS + PPA North Sea H PG 76-22 315-325 305-315 SBS Venezuela Alaskan Slope I PG 70-28 322-336 302-313 Air Blown /Canada J PG 64-16 307-313 267-273 None West Texas California K PG 64-16 285-305 265-285 None Valley 18% California L PG 76-22 320-330 290-300 Crumb Valley Rubber SBS + M PG 82-22 285-300 250-260 Venezuela Sasobit N PG 82-22 325-340 300-320 SBS Mexico O PG 64-28 313-324 291-300 None Venezuela