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A report, completed at the request of Walter Berry. George Washington Lopp examined the status of Quentin Roosevelt's grave, ownership of land by Leferre, Turpin, Quenardel, gift of land, the appearance of the gravesite, and several papers attached to main report.

BD-545 RPWO #38, Asphalt mixtures designed using modern conventional methods, whether Marshall or Superpave methodologies, fail to address the cracking performance of these mixtures. Research previously conducted at the University of Florida for the Florida Department of transportation has identified key mixture parameters that control cracking performance. These parameters can be obtained from a series of relatively simple tests performed using the Sueperpave indirect tension tests (IDT). Traditionally, this equipment is large, heavy, requires fixed utilities, and specialized training. A simple IDT testing platform has been developed that removes these restrictions. This platform is small, and portable, incorporating all of the most important performance features of the heavier fixed systems. Evaluation of the Simple IDT was conducted, at three different testing temperatures, using a laboratory prepared mixture. The results show equivalent comparison of the key mixture parameters versus two different fixed IDT systems, one at UF and the other at the FDOT State Materials Office. Additionally, software has been developed to aid the operator in performing the tests on the Simple IDT, thereby reducing the need for specialized training. Work continues refining a sensor system to measure the on-specimen deformations, which would eliminate the need to glue targets or gage points on the specimen faces, reducing this additional specimen preparation.

Repeated traffic loading will result in accumulation of damage, but this damage will heal during periods of no traffic loading.

BD545-53, A dog-bone direct tension test (DBDT) to accurately determine tensile properties of asphalt concrete, including OGFC, was conceived, developed and validated. Resilient modulus, creep, and strength tests, were performed at multiple temperatures on dense-graded and OGFC mixtures produced two, aggregates with both the newly developed DBDT and existing Superpave IDT. Excellent, correspondence was observed between properties determined from each type of test, indicating that, fundamental properties can be accurately determined using either test. Differences in strain rate, between the two tests resulted in expected differences in strength and failure strain. Creep compliance, was highly correlated between the two tests but was lower for IDT than for DBDT, which can be, attributed to the higher confinement in IDT. It was concluded that DBDT compliance is more, appropriate for uniaxial stress states, while IDT compliance is more appropriate for biaxial stress states., Continued use of Superpave IDT was recommended because it is much more practical. A composite, specimen (OGFC on HMA) direct tension fracture test was developed to evaluate the effects of OGFC, and interface conditions on top-down cracking performance. Results indicated that use of polymer, modified bonding agents can significantly improve cracking resistance of pavements with OGFC., Continuum and micro-mechanics based FEM models developed to predict cracking performance of, composite mixtures indicated that traditional OGFC accelerates development of top-down cracking and, should not be assigned a structural benefit in pavement design. The modeling results also indicated the, benefit of polymer-modified bonding agents. The benefits of using micro-mechanics to optimize, OGFC design were illustrated. Recommendations were made for continued development and validation, of testing and modeling of composite systems to optimize OGFC design.

00084222, This study involved the identification and evaluation of laboratory conditioning methods and testing protocols considering heat oxidation, moisture, and load that more effectively simulate asphalt mixture aging in the field, and thereby help to properly assess asphalt mixture property changes over time. In this study, aging was defined as any detrimental effect on asphalt mixture properties during pavement life. Three laboratory conditioning procedures were identified and further developed to evaluate the effects of heat oxidation, moisture, and repeated load: heat oxidation conditioning (HOC), cyclic pore pressure conditioning (CPPC), and repeated load conditioning (RLC) respectively. Results indicated that the most effective approach to effectively induce changes in damage and fracture-related properties involved a combination of HOC and CPPC. HOC was accomplished using the Superpave Long-Term Oven Aging (LTOA) procedure. The combination of LTOA and CPPC was found to effectively induce reduction in failure strain and fracture energy (FE) limit of mixtures to levels consistent with those observed in the field. Although RLC was able to effectively induce damage, the method was found to be impractical because of issues regarding the identification of proper load level to achieve damage without fracture during RLC. The energy ratio (ER) parameter was used for relative comparison of cracking performance of mixtures subjected to similar levels of HOC and CPPC. Results showed that addition of hydrated lime improved cracking performance of granite mixtures, which exhibited higher ER than the limestone mixture tested. In addition, the limestone mixture tested exhibited better cracking performance (higher ER) than the granite mixture without lime. Recommendations were made for additional field and laboratory studies using the conditioning procedures developed in this study.

BD545-41

00084221, It has been found that binder testing methods in current specifications do not accurately predict cracking performance at intermediate temperatures. Fracture energy has been determined to be strongly correlated to fracture resistance of asphalt mixture, so a new fracture test and interpretation system was developed based on finite element analysis (FEA) and prototype testing on a servo-hydraulic testing machine to consistently measure fracture energy of binder at intermediate temperature. For evaluation, the new test was applied to a range of binders, including unmodified binder, SBS-modified binder, rubber-modified binder, and hybrid binder from pressure aging vessel (PAV) residue or recovered from field test sections. Statistical analysis was conducted on test results, which showed that the new fracture test and interpretation system clearly differentiated binders by fracture energy values. Expected trends in fracture energy between binders were observed. It was also shown that, for the same binder, fracture energy is independent of loading rate evaluated in this study and test temperature from 0 to 15°C. Thus, fracture energy appeared to be a fundamental property of binder, which does not depend on test condition, and can be determined by tests performed at a single temperature and loading rate. The results also showed that different types of binder have different characteristic true stress-true strain curves, which can be used to identify binder type, modifier type, and relative content. Basic principles were proposed to identify the presence of modifier from true stress-true strain curves. A detailed testing protocol was recommended. The protocol helps assure the appropriate loading rate range so that the complete true stress-true strain curve can be identified for accurate determination of fracture energy.

BDK75 977-60, Since the late 1970s, FDOT, has applied an interlayer, of Asphalt Rubber, Membrane Interlayer, (ARMI) to asphalt roadway, surfaces. ARMI layers are, constructed by spraying, asphalt rubber binder onto, the asphalt, covering the, layer with no. 6 stone, and, rolling the stone into the, asphalt with a pneumatic, tire roller. A fi nal layer of, asphalt is applied on top, of the ARMI layer. ARMI, adds cost to the asphalt, roadway project but has, been used as a means to, extend the life of the roadway by mitigating, refl ective cracking.

This study involved the continuous monitoring of material properties and field performance of twelve Superpave project sections in Florida for the establishment of reasonable and effective mixture design guidelines and criteria, the identification and development of material property relations, and the evaluation of ongoing national and Florida design model development efforts. Field performance evaluation was conducted to identify performance-related criteria using the Dominant Aggregate Size Range-Interstitial Component (DASR-IC) parameters, which characterize the mixture gradation. Results indicated that the introduction of DASR-IC criteria into current mix design guidelines and specifications will assure good and consistent performance of Superpave mixtures. Identification of mixture parameters that control cracking performance led to the development of relationships to predict fundamental mixture properties (e.g., fracture energy and creep rate) based on DASR-IC parameters within the acceptable range. Based on the evaluation of existing pavement performance prediction models, the Enhanced Hot-Mix Asphalt Fracture Mechanics based Model (HMA-FM-E) was clearly determined to be the best choice for further top-down cracking prediction model development for use in the design of flexible pavements. It was found that the fracture resistance of asphalt mixtures was significantly reduced in sections subjected to moisture damage, which obviously affected mixture performance in the field. Development of a comprehensive and user-friendly database was continued in this phase. This has resulted in one of the most extensive datasets of research quality Superpave data on real-world projects. Recommendations were made for further investigations on the continuation of Superpave projects monitoring in Florida.