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63 TABLE 14 Coarse aggregate angularity criteria for state agencies with altered criteria Agency Criteria Arizona -/851 for all traffic levels and depths Arkansas 98/80 for all traffic levels/depths Idaho 90/60 for all traffic levels and depths Kansas Added requirement of 50/- for < 0.3 million ESALs at a depth greater than 100 mm. 50/- specified for shoulder mixes regardless of depth Kentucky 75/- 30 million ESALs Louisianna 75/- low traffic, 95/- medium traffic, 98/- high traffic Minnesota 30/30 3 million ESALs match AASHTO M323 Mississippi -/90 12.5 mm NMAS or smaller, -/80 for 19.0 mm NMAS, -/70 for 25.0 mm NMAS Montana 75/60 0.3-3 million ESALs; > 3 million ESALs match AASHTO M323 New Jersey Surface and Intermediate lifts: 95/90 for low, medium and high traffic levels, 100/100 for very high traffic levels Base lifts: 80/75 for low, medium and high traffic levels, 100/100 for very high traffic levels Utah 95/90 for Category 1 traffic (National Highway System and truck routes); 85/80 for 19.0 and 25.0 mm, 90/90 for 12.5 and 19.0 mm NMAS Category 2 pavements (all others) 1 Percentage of particles with one or more and two or more fractured faces, respectively. regarding the influence of the parent gravel cobble size on the F&E. One of these states, Colorado, tested all of its sources ability to produced high percentages of fractured faces. and found only two sources that exceeded the 51 ratio by Quarried aggregates are generally expected to have two or more than 2%. The current criterion specified by AASHTO more fractured faces. However, for the states that specify a M323 for pavements with more than 1 million ESALs is 10%. fractured face test, 81% stated that the test was performed on Of the state agencies that specify ASTM D4791 or a simi- all aggregates, while 19% stated that it was only performed lar agency test method, 63% specify criteria that match those on gravel sources. outlined in AASHTO M323. Kentucky specifies less than 10% of 51 particles for all traffic levels. Connecticut, Hawaii, New Mexico, Utah, and Wyoming specify a maximum of 20% 3.2.4 Flat and Elongated Particles particles exceeding the 31 ratio. In Utah, these criteria only apply to the +9.5-mm material. Texas specifies a maximum Superpave specifies that the percentage of flat and elon- of 10% of 31 particles. Minnesota specifies flat or elongated gated particles with a maximum-to-minimum (length-to- (width to thickness or length to width, respectively) based on thickness) ratio greater than 5 be determined according to a 31 ratio. Only Idaho specifies less restrictive criteria, allow- ASTM D4791. Flat particles are defined as those particles ing 15% by weight of particles to exceed the 51 ratio. In whose width to thickness exceeds some ratio, typically 51 addition to the 10% 51 requirement, Ontario specifies a or 31. Elongated particles are defined as those particles maximum of 15% or 20% of particles exceeding the 41 whose length to width exceeds some ratio, similar to flat par- ratio. Six agencies report having more restrictive require- ticles. AASHTO M323 considers both flat particle and elon- ments for aggregate used in stone mastic asphalt, which are gated particle shapes to be susceptible to breakdown during typically a maximum of 20% of 31 and 5% of 51 particles. production, placement, and compaction and, therefore, spec- ifies the ratio of the maximum-to-minimum dimension of the particle. 3.3 SOURCE PROPERTIES ASTM D4791 is specified by 79% of the responding agen- cies. An additional three agencies (6%) use an agency pro- 3.3.1 Introduction cedure similar to ASTM D4791. Georgia DOT also uses a method similar to ASTM D4791, but instead of defining the Source property levels are not specified in the AASHTO minimum dimension of the particle as the maximum thick- Superpave Specifications. Source property tests are generally ness, it instead defines the minimum dimension as the aver- related to the durability of the aggregate during construction, age thickness. This method is a more restrictive test than is wetting and drying, freezing and thawing, and resistance to ASTM D4791. West Virginia also has its own test proce- abrasion under traffic as well as to contaminants such as dele- dure. Four states (8%) do not specify any requirements for terious materials. The need for a different level of source prop-