The effect of 11 asphalt binders on the moisture sensitivity of a mixture were measured using the Hamburg Wheel- Tracking Device (Hamburg WTD). The Hamburg WTD tests a slab of hot- mix asphalt submerged in hot water by rolling a steel wheel across its surface. The binders consisted of two unmodified asphalt binders, an air- blown asphalt binder, and eight polymer- modified asphalt binders. The continuous high- temperature performance grades (PG's) ranged from 67 to 77. Two aggregates were used: diabase and limestone. The mixture results using the limestone aggegate could not be used to evaluate the asphalt binders because the Hamburg WTD crushed the limestone aggregate. A test temperature of 58 degrees Celcius was chosen for the diabase mixtures based on trial tests using the air- blown and unmodified PG 70- 22 asphalt binders. It was expected that most of the mixtures with polymer- modified asphalt binders would have greater resistance to moisture damage than the mixture with the unmodified PG 70- 22 asphalt binder because they would provide increased adhesion to the aggregate or create a network within the asphalt that was more resistant to water penetration. However, only one polymer- modified asphalt binder provided a greater resistance at a 5- percent level of significance. Some of the asphalt binders provided significantly different resistances to moisture damage that were not related to differences in cohesive strength as measured by the asphalt binder parameter G*/sin(delta) at 58 degrees Celcius. It was concluded that polymer- modified asphalt binders having the same G*/sin(delta) can provide different adhesive strengths and/or different resistances to water penetration. Reasons for these differences need to be determined.

The overall objective of this study was to determine if the Superpave high-temperature rheological properties of polymer-modified asphalt binders correlate to asphalt mixture rutting resistance. An emphasis was placed on evaluating polymer-modified asphalt binders with identical (or close) high-temperature performance grades (PG's), but varied polymer chemistries. Eleven asphalt binders were obtained for this study: two unmodified asphalt binders, an air-blown asphalt binder, and eight polymer-modified asphalt binders. High-temperature asphalt binder properties were measured by a dynamic shear rheometer (DSR). Mixture rutting resistance was measured by repeated shear at constant height (RSCH), and the French Pavement Rutting Tester (French PRT). The first objective was to verify the findings of a previous study using a different aggregate. In the previous study, it was found that the Superpave high-temperature asphalt binder properties correlated to mixture rutting resistance with few outliers, and a change in high-temperature PG from 70 to 76 increased rutting resistance. However, the correlation between RSCH and asphalt binder G*/sind (delta) depended on DSR frequency. The data suggested that a low DSR frequency, such as 0.1 rad/s, might provide a better grading system than the standard DSR frequency of 10.0 rad/s. This would require a change in the current asphalt binder specification. A diabase aggregate was used in a previous study. The data using a second aggregate, a limestone aggregate, in combination with four of the asphalt binders, agreed with the findings from the diabase mixtures. The second objective was to retest the diabase mixtures at 70 degrees Celsius using RSCH. The test temperatures used in the previous study were 50 degrees Celsius for RSCH and 70 degrees Celsius for the French PRT. The polymer-modified asphalt binders had continuous high-temperature PG's ranging from 71 to 77. Therefore, it was recommended that the test temperature for RSCH be increased to 70 degrees Celsius. Again, the correlation between RSCH and G*/sind was dependent on DSR frequency. The data suggested that a low DSR frequency, such as 0.1 rad/s, might provide a better grading system. However, it is not known whether this finding applies to pavements, or is related to the accelerated nature of the RSCH test. Furthermore, G*/sind (delta) at 0.1 rad/s did not clearly provide a better correlation to RSCH than the high-temperature PG's of the asphalt binders. The degree of correlation between the French PRT and G*/sind at 70 degrees Celsius did not depend on DSR frequency, and there was only one outlier. A correlation between the French PRT and high-temperature PG provided no obvious outliers. No changes to the specification are recommended based on the French PRT results.

This book is dedicated to the use of nanomaterials for the modification of asphalt binders, and to investigate whether or not the use of nanomaterials for asphalt mixtures fabrication achieves more effective asphalt pavement layers. A total of 10 contributions are included. Four are related to "Binder's modification" and five to "Asphalt mixtures' modification". The remaining contribution is a review of the effects of the modifications on nanomaterials, particularly nanosilica, nanoclays and nanoiron, on the performance of asphalt mixtures. The published group of papers fosters awareness about the use of nanomaterials to modify asphalt mixtures to obtain more performant and durable flexible road pavements.

Asphalt Pavements provides the know-how behind the design, production and maintenance of asphalt pavements and parking lots. Incorporating the latest technology, this book is the first to focus primarily on the design, production and maintenance of low-volume roads and parking areas.Special attention is given to determining the traffic capacity, re

This thesis investigates and documents fundamental studies of highway materials (asphalt engineering properties) especially on different modified asphalt binders and mixtures in order to understand failure mechanisms at low temperature and superior performance of such asphalt binders with the aim of preventing premature cracking on Ontario highways. In addition, seven asphalt binders of different compositions were used as a template for study and this research work is tailored towards Superpave® performance-based specification testing with the aim of improving asphalt pavement performance under various conditions and consequently reducing premature cracking in order to achieve long lasting highways. Based on the actual applied pattern of Superpave® specification criteria, the mechanical responses of the binders are analyzed by extended bending beam rheometer (eBBR), tensile stress ductilometer (Petrotest DDA3®), compact tension test (Instron AsphaltPro®), double-edge-notched tension and single-edge-notched tension (MTS 810 universal testing machine) protocols. The objective of this study entails establishing and developing of a proper procedure for the testing of binders with the aim of ranking (grading) the performance after validation of laboratory and field experiments. Analysis of the results appears to show that the premature distress on the Highway 417 trial sections can be attributed to reversible aging tendency (wax crystallization) at low temperatures coupled with low fatigue resistance of the binders. The results suggest that different polymer modifications had significant influence on the performance of asphalt mix as demonstrated from the results obtained from essential and plastic work of fracture using double-edge-notch-tension test (DENT). Crack tip opening displacement (CTOD) parameter consistently show the performing grading of asphalt binder while compact tension test protocol provides plane strain fracture toughness (K1c) which could be used to rank binders with respect to fracture resistance at low temperature. Hence, CTOD is a promising parameter which can be used to establish performance ranking of the binders.