The purpose of this study is to evaluate warm mix asphalts (WMA) with recycled asphalt pavement (RAP) from Nevada. For this study, four different warm mix technologies and four different aggregate sources with two different percentages of recycled asphalt binder ratios were used. Aggregates from Lone Mountain, North Tenaya, Spanish Springs and Lockwood were used with appropriate binders for the particular climate conditions in those areas. All the aggregates were lime-marinated, as per requirement of the Nevada Department of Transportation. Advera, Evotherm 3G, Sonnewax and waterfoam were the warm mix technologies evaluated. All four WMA mixtures satisfied all the criteria for resistance to moisture damage with or without RAP for all the aggregate sources used. In terms of fatigue, the WMA mixtures showed better results than the HMA mixture. But for the rutting resistance all of the WMA mixtures showed lower values than the HMA mixtures. This was expected, even though the WMA's rutting resistance improved when RAP was added.

The state of Nevada is experiencing permanent deformation problems with hot mix asphalt pavements at or near intersections. The Nevada Department of Transportation (NDOT) is currently using a Type 2C dense graded mixture in most of its construction. The NDOT Type 2C mixture showed excellent rutting resistance under normal highway traffic, while its resistance to rutting and shoving at intersections in the hot environment of Las Vegas is questionable.The overall objective of this research was to identify a hot mix asphalt (HMA) mixture with good resistance to rutting and shoving at intersections. To this end, two laboratory evaluations were conducted: I. Postmortem evaluation of in-service intersections and II. Laboratory evaluation of different aggregate gradations. Based on past performance and data generated from this research, five different aggregate gradations were selected for laboratory evaluation. Aggregates were sampled from the Sloan quarry located south of Las Vegas, Nevada, along Interstate 15. All five gradations were mixed with a polymer-modified PG76-22NV asphalt binder which is the current specified asphalt grade for southern Nevada. A Hveem mix design was conducted for each of the five mixtures. This part of the research re-evaluated the APA and RSCH as potential candidates for a mix design test for intersection mixtures. In addition, the triaxial compression strength test and the repeated load triaxial test (RLT) were also evaluated. All tests ranked the permanent deformation resistance of the five mixtures in the same order. Additionally, dynamic mechanistic analyses were performed as an attempt to determine the pavement responses under a heavy loaded truck at and away from the intersection. The findings of the mechanistic analyses were used to predict permanent deformation potential in the HMA layer. To this end, permanent deformation models for NDOT Type 2C mixture were developed in the laboratory using the repeated load triaxial (RLT) and the repeated shear at constant height (RSCH) testing. he actual specifications used by NDOT for the various permanent deformation tests were reviewed and adjusted for the HMA mixtures that are going to be used at intersections and stopping areas. (Abstract shortened by UMI.)

At head of title: National Cooperative Highway Research Program.

The purpose of this research was to evaluate the impact of hydrated lime on the mechanical properties of typical HMA mixtures in Nevada. This research differed from previous studies in several respects. First, because lime is used in HMA primarily for anti-stripping benefits, previous studies rarely quantified lime's other performance benefits. Second, because testing is typically performed on only the HMA mix being considered for a project, and only as necessary to satisfy specifications, typical studies do not capture the full range of failure modes and environmental stresses. Furthermore, once specifications are met, test results are rarely translated into pavement performance characteristics. This research, by contrast, evaluated two typical HMA mixtures from the northern part of Nevada and two HMA mixtures from the southern part of Nevada used by NDOT with the most widely accepted laboratory tests. The Hveem mix design method was used in all mixtures. The tests were conducted at 0 and 6 freeze thaw cycles. The moisture damage was evaluated through the dynamic modulus test at various temperatures and frequencies. The asphalt pavement analyzer test and the repeated load triaxial test were used to evaluate the permanent deformation of the mixtures. The flexural beam test was used to assess the fatigue resistance and the thermal stress restrained specimen test was conducted to evaluate thermal cracking resistance. Additionally, mechanistic analysis was performed as an attempt to determine the pavement responses for each mix. In overall, the laboratory results and the mechanistic analysis showed that lime improved the mechanistic properties of Nevada's mixtures and its relative performance when is compared with the un-treated mixtures.