This article focuses on current and potential developments in pavement engineering where the unique properties of nanomaterials can be used to improve the built environment. The original paper on which this article is based was chosen as Best Paper (Pavements) for 2009 by the SAICE Transportation Division.

Potential applications of nanotechnology in pavement engineering

Mechanical Properties of Asphalt Concrete Modified with Carbon Nanotubes (CNTs)

Thermal or low temperature cracking is among the most common distresses in asphalt pavements, occurring in cold regions and exerting a detrimental effect on the quality and life of the pavement. Ha...

Investigation the effect of short term aging on thermodynamic parameters and thermal cracking of asphalt mixtures modified with nanomaterials

Evaluation Of Physical-Rheological Properties of Nano Titanium Dioxide Modified Asphalt Binder and Rutting Resistance of Modified Mixture

This study investigates the effect of using Fume Silica (Aerosol 300) alone and together with crumb rubber (CR) in bitumen modification on the traditional and rheological properties of the binder and compares it to the SBS modified binder. Using the aerosol additive in the binder at the rates of 0.5%, 1%, 1.5%, and 2% were determined as the most convenient ratio and CR+aerosol modified binders were prepared per this ratio. The binders were subjected to the softening point, viscosity, frequency sweep, bending beam rheometer (BBR), and Fourier Transform Infrared spectroscopy (FTIR) tests in the context of the study. Besides, the optimum conditions were determined according to the response functions by designing an experiment with statistical regression according to the Response surface methodology (RSM). The results indicate that the optimum aerosol ratio is 1.5%. With the use of 1.5% aerosol in 6% CR modification per bitumen weight, it was found that (1) the softening point increases and the temperature sensitivity decrease in comparison to other binders, (2) the consistency of the binder increases, (3) the complex modulus values increase and become more resistant to rutting, (4) the low-temperature parameters enhance by performing more flexible behavior, (5) there may be physical changes in the structure even though there is no chemical reaction in the binder with the use of CR and aerosol additives, and (6) the experimental data and theoretical data obtained from the RSM method are consistent as per the statistical analysis.

/pdf/research-on-the-rheological-properties-of-asphalt-binder-1nlebdfb.pdf

Research on the Rheological Properties of Asphalt Binder Modified by Fume Silica and Crumb Rubber Compound

In the recent times, asphalt binder modification has emerged an inevitable alternative in the paving industry to ensure better performing pavements against the distresses caused by common factors such as; moisture susceptibility and high-temperature sensitivity of asphalt binders. Nanomaterials, as asphalt-modifiers, have proved to be the most promising materials in the industry owing to their higher active surface area and small particle size. This study was devoted to assessing the modification influence of three different types of nanomaterials, including nano-Bentonite, nano-CaCO3, and ZycoTherm, on the properties of asphalt binder and HMA. Conventional and rheological tests on asphalt binders, as well as, Marshall mix design and modified Lottman test on laboratoryprepared HMA specimens were conducted in order to signify the influence of nanomodification. The research findings suggested that nanomaterials can potentially enhance the high-temperature susceptibility resistance, storage stability, and rheological properties of asphalt binder samples. Mix design results revealed that the optimum binder contents decreased and Marshall stabilities were slightly improved with nanomodification. Moreover, the modified Lottman test results indicated that 0.1 % of ZycoTherm increased the TSR by 22 % as compared to the control mixture that infers its efficiency in terms of improving the HMA resistance against the moisture-

/pdf/assessment-of-asphalt-binders-and-hot-mix-asphalt-modified-21bsvxreid.pdf

Assessment of Asphalt Binders and Hot Mix Asphalt Modified with Nanomaterials

Asphalt pavements are amongst the most recycled materials in the contemporary world depending on the environmental and financial advantages. The introduction of Recycled Asphalt Pavement (RAP) on newly produced asphalt pavement is possible by the utilization of rejuvenating agents, which should contain oily fractions. For this purpose, within the scope of this study, three types of agents with optimum amounts (by weight of bitumen) were utilized 5.4% Waste Engine Oil (WEO), 5.1% Waste Vegetable Oil (WVO), and 6.8% Commercial Rejuvenating Agent (CRA). The highest applicable RAP content in mixtures depends on the rejuvenator type determined by Marshall Mix Design tests (air voids, flow, and stability). Rejuvenation facilitated the use of 50 to 60% of additional RAP material in the mixtures depending on the rejuvenator type. Indirect Tensile Strength (ITS) test results declared that RAP mixtures, when subjected to the rejuvenation process, resulted in relatively less brittleness and enhanced durability properties compared to the unmodified ones. Additionally, cost comparison analyses demonstrated encouraging results as the cost-benefit ratio exceeded up to 55% for mixtures involving high percentages of rejuvenated RAP. As a final analysis, Return on Investment (ROI) values were calculated for each rejuvenator type by the cost of upgrading the facility to handle RAP and the profit of RAP usage. Consequently, ROI was calculated as a return time in months, which unveils an extremely profitable opportunity in the industry.

/pdf/feasibility-and-mixture-performance-assessment-of-waste-oil-1104cmc4.pdf

Hameedullah Raufi

Papers

Assessment of Asphalt Binders and Hot Mix Asphalt Modified with Nanomaterials

Feasibility and mixture performance assessment of waste oil based rejuvenators in high-RAP asphalt mixtures