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This study aims to optimize the integration of dredged sediments as fillers in formulations of hydrocarbon materials such as "mastic asphalt" for sealing applications. River sediments were collected from the Hauts de France region are the following ones: Aire sur la Lys (ASL), Urban Community of Arras (ARS), European Metropolis of Lille (MEL), and Noyelles sous Lens (NSL) to identify the impact of integrating them in asphalt formulations. Pure asphalt mortars were formulated (AP1) according to the specifications. Asphalt based on limestone fillers have achieved mechanical performance set by the standards. It can be seen that MEL and NSL sediments have a limited use because of their high organic matter content and their high rate of Intergranular voids (RV), which leads to overconsumption of Bitumen. However the calcination of these sediments at 550 °C can remove the organic matter and give a better improvement in physical and mechanical performance than the quicklime treatment. Asphalt-based calcined sediment at 550 °C (NSLC) has been shown to deliver up to 80% improvements in the mechanical performance in comparison to the raw sediment mix. In addition, the use of a soft grade of Bitumen gave impressive benefits with the sediment fillers which can reach up to 23% substitution and reducing the quantity of Bitumen up to 19%. [Display omitted] • Sediment can be used as an alternative to limestone filler in mastic asphalt mix. • Raw sediment can be used with a substitution rate of limestone filler about 20%. • Organic matter of sediment tends to increase filler absorption of bituminous binder. • Sediment filler should be treated by calcination before their use in asphalt mastic. • Soft grade bituminous binder provides solution to the high filler absorption. [ABSTRACT FROM AUTHOR]

Coarse aggregate is the main component of asphalt mixtures, and differences in its morphology directly impact road performance. The utilization of standard aggregates can benefit the standard design and performance improvement. In this study, 3D printing technology was adopted to prepare artificial aggregates with specific shapes for the purpose of making the properties of artificial aggregates to be similar to the properties of natural aggregates. Through a series of material experiments, the optimal cement-based material ratio for the preparation of high-strength artificial aggregates and corresponding manufacturing procedures have been determined. The performance of the artificial aggregates has been verified by comparing the physical and mechanical properties with those of natural aggregates. Results indicate that using 3D printing technology to generate the standard coarse aggregate is feasible, but its high cost in implementation cannot be ignored. The 3D shape of the artificial aggregate prepared by the grouting molding process has a good consistency with the natural aggregate, and the relative deviation of the overall macro-scale volume index of the artificial aggregate is within 4%. The average Los Angeles abrasion loss of artificial cement-based aggregate is 15.2%, which is higher than that of diabase aggregate, but significantly lower than that of granite aggregate and limestone aggregate. In a nutshell, 3D printed aggregates prepared using the optimized cement-based material ratio and corresponding manufacturing procedures have superior physical and mechanical performance, which provides technical support for the test standardization and engineering application of asphalt pavements. [ABSTRACT FROM AUTHOR]

The usage of recycled asphalt shingles (RAS) in hot mix asphalt (HMA) pavements provides many benefits as long as they are properly engineered into the various HMA mixes. Contractors, consultants, and Departments of Transportation have evaluated the performance of these various materials, although they are still only used in a limited number of areas. Alternatively, recycled asphalt pavement (RAP) is recognized as a high value recycled material and is actually the most recycled material in North America. In Ontario, RAP is successfully used in most HMA. Related studies on HMA containing RAS and RAP are limited in Canada although recently studies and field trials on effectively using RAS in HMA in Ontario have been completed by the Centre of Pavement and Transportation Technology (CPATT) at University of Waterloo in partnership with Miller Paving Ltd and the Ontario Centre of Excellence. This paper presents key findings from a comprehensive laboratory investigation and analysis of six asphalt mixes with RAS and RAP in Ontario through dynamic modulus, resilient modulus, thermal stress restrained specimen, and flexural fatigue testing. Using RAS alone or combining with RAP makes the asphalt stiffer at high and low temperatures respectively. Lowering the low temperature performance grade of the asphalt binder by 6 °C and incorporating 3% RAS or less with RAP in HMA mix design can result in meeting the appropriate specification. While field testing of RAS pavements demonstrated that surface friction properties are in good condition in various environmental and loading conditions, the laboratory test results and field performances indicate that RAS can be a useful additive to asphalt mixes in Ontario hot mix pavement through reasonable mix design. [ABSTRACT FROM AUTHOR]