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The impact of new generation wide-base tires (NGWBT) compared to conventional dual-tire assemblies (DTA) has been a controversial topic over the past years. Although NGWBT can improve fuel efficiency and ride quality, they may cause more pavement damage, due to the reduced contact area between tire and pavement. The degree of pavement damage caused by NGWBT and DTA varies based on pavement structure and environmental conditions. The goal of this research is to investigate the impact of these tire configurations (NGWBT and DTA) on four different pavement structures used in the City of Calgary, which has cold weather conditions. For this purpose, three-dimensional (3D) finite element (FE) models were developed and validated. The actual tire-pavement interaction, including the dimensions and shape of the contact area, as well as the non-uniform contact stress distribution over the contact area was considered for each load case (NGWBT and DTA). Using the 3D FE model, the strain values at critical locations were calculated and used to perform pavement damage analysis by considering bottom-up fatigue cracking and subgrade rutting. The results showed that, on average, the longitudinal strains at the bottom of the asphalt layer induced by NGWBT are 12.8–18.3% higher than the strains induced by DTA. In addition, considering a market penetration rate of 20% for NGWBT, the normalized combined damage ratios \({(\mathrm{CDR}}_{\mathrm{NGWBT}}/{\mathrm{CDR}}_{\mathrm{DTA}})\) for the strongest and weakest pavement structures investigated were determined to be 1.057 and 1.115, respectively, indicating that weaker pavement structures are more vulnerable to NGWBT.
Mohamad Molavi Nojumi; Manjunath Basavarajappa; Leila Hashemian; Alireza Bayat. Investigation of the Impact of Tire Configurations on Different Pavement Structures Using Finite Element Analysis. International Journal of Pavement Research and Technology 2021, 1 -16.
AMA StyleMohamad Molavi Nojumi, Manjunath Basavarajappa, Leila Hashemian, Alireza Bayat. Investigation of the Impact of Tire Configurations on Different Pavement Structures Using Finite Element Analysis. International Journal of Pavement Research and Technology. 2021; ():1-16.
Chicago/Turabian StyleMohamad Molavi Nojumi; Manjunath Basavarajappa; Leila Hashemian; Alireza Bayat. 2021. "Investigation of the Impact of Tire Configurations on Different Pavement Structures Using Finite Element Analysis." International Journal of Pavement Research and Technology , no. : 1-16.
Asphalt emulsion is one of the most common materials used in the pavement industry for surface treatment and other applications such as stabilization of pavement base course. Because asphalt emulsions do not require heating at high temperatures for these applications, this feature makes it environmentally friendly due to energy savings and provide safer working conditions by eliminating dangerous toxic fumes. This study investigates the application of using asphaltenes derived from Alberta oil sands to modify asphalt emulsion for base course layer application. Asphaltenes is a waste material of insignificant value with no notable applications in the pavement industry. The amount of asphaltenes to be added for asphalt emulsion modification is determined in the present study through the Marshall stability test, indirect tensile strength test, and wheel tracking test. Asphaltenes from two different sources are used for the asphalt emulsion modification. The modified asphalt emulsion is cured using a low-temperature evaporation technique to recover the asphalt residue. The rheological properties of recovered residue from modified asphalt emulsions are evaluated at high temperatures using a dynamic shear rheometer (DSR). The results indicate that the asphaltenes from both sources significantly increase the Marshall stability and indirect tensile strength of the mixes. The rutting resistance of the modified mixes from the wheel tracking test is found to improve significantly by increasing the number of passes by more than 200% compared to the control sample. Furthermore, the modified asphalt emulsion residues show an improvement in rheological properties at high temperatures.
Manjunath Basavarajappa; Farshad Kamran; Nura Bala; Leila Hashemian. Rutting Resistance of Stabilized Mixes Using Asphalt Emulsion and Asphaltenes. International Journal of Pavement Research and Technology 2021, 1 -13.
AMA StyleManjunath Basavarajappa, Farshad Kamran, Nura Bala, Leila Hashemian. Rutting Resistance of Stabilized Mixes Using Asphalt Emulsion and Asphaltenes. International Journal of Pavement Research and Technology. 2021; ():1-13.
Chicago/Turabian StyleManjunath Basavarajappa; Farshad Kamran; Nura Bala; Leila Hashemian. 2021. "Rutting Resistance of Stabilized Mixes Using Asphalt Emulsion and Asphaltenes." International Journal of Pavement Research and Technology , no. : 1-13.
Pavement temperature prediction plays a key role in determining the structural capacity and deflection of asphalt pavement, owing to the viscoelastic behavior of asphalt. Thus, a high degree of accuracy is desirable for the prediction of asphalt temperature from available parameters such as air temperature and solar radiation. Asphalt temperature prediction models can be based on different approaches, including analytical, numerical, and statistical methods. Each of these models has its own strengths and weaknesses, and their accuracy varies based on site conditions. The goal of this research is to compare the accuracy of machine learning approach in general with existing models for prediction of temperature in asphalt pavements, based on 6 years of data collected from temperature sensors embedded in an instrumented test road in Alberta. A sensitivity analysis was performed to determine the most important parameters for prediction of temperature, and MATLAB regression learner was used for implementing machine learning-based algorithms based on parameters, which were determined to be air temperature, solar radiation, and day of the year. The machine learning methods were compared with existing literature models for prediction of average, minimum, and maximum daily pavement temperatures at different depths throughout the asphalt layer. The predicted results were validated by comparison with available field data. All machine learning algorithms used in this study resulted in the prediction of temperature values with higher accuracy compared to existing models, demonstrating the applicability of these machine learning models for improved pavement temperature prediction.
Mohamad Molavi Nojumi; Yunyan Huang; Leila Hashemian; Alireza Bayat. Application of Machine Learning for Temperature Prediction in a Test Road in Alberta. International Journal of Pavement Research and Technology 2021, 1 -17.
AMA StyleMohamad Molavi Nojumi, Yunyan Huang, Leila Hashemian, Alireza Bayat. Application of Machine Learning for Temperature Prediction in a Test Road in Alberta. International Journal of Pavement Research and Technology. 2021; ():1-17.
Chicago/Turabian StyleMohamad Molavi Nojumi; Yunyan Huang; Leila Hashemian; Alireza Bayat. 2021. "Application of Machine Learning for Temperature Prediction in a Test Road in Alberta." International Journal of Pavement Research and Technology , no. : 1-17.
The current study investigates the application of asphalt binders from different sources modified with asphaltenes in high modulus base courses (HMAC). For this purpose, one crude oil asphalt binder and four asphalt binders derived from various sources of Alberta oilsands were studied. Witczak regression model was used to determine the minimum performance grade to meet the dynamic modulus requirement for HMAC. Asphaltenes were added in different quantities for modification of the asphalt binders. The effect of asphaltenes modification on the viscosity of the binders was studied using a rotational viscometer. Also, the chemical composition of the asphaltenes-modified binders was determined by SARA analysis. The results of the rheological analysis indicated that asphaltenes effect on binders performance at high temperatures was more than its negative impact at low temperatures. Furthermore, it was determined that binders from the Alberta oilsands modified with asphaltenes could achieve the performance grade requirements for HMAC applications.
Amirhossein Ghassemirad; Nura Bala; Leila Hashemian; Alireza Bayat. Application of asphaltenes in high modulus asphalt concrete. Construction and Building Materials 2021, 290, 123200 .
AMA StyleAmirhossein Ghassemirad, Nura Bala, Leila Hashemian, Alireza Bayat. Application of asphaltenes in high modulus asphalt concrete. Construction and Building Materials. 2021; 290 ():123200.
Chicago/Turabian StyleAmirhossein Ghassemirad; Nura Bala; Leila Hashemian; Alireza Bayat. 2021. "Application of asphaltenes in high modulus asphalt concrete." Construction and Building Materials 290, no. : 123200.
Permanent deformation and moisture sensitivity are the two main challenges with the performance of asphalt emulsion-stabilized base courses. This study investigates the application of asphaltenes as a waste material derived from Alberta oil-sands bitumen in improving stabilized base course mechanical properties. Hence, 1% to 3% of asphaltenes by total weight of mix is added to a granular aggregate stabilized with asphalt emulsion. The impact of asphaltenes on the tensile strength, moisture susceptibility, and rutting performance of the modified mixtures is investigated. The asphaltenes-modified base courses have higher tensile strength and rutting resistance, while their moisture susceptibility is slightly lower than the control mix.
Farshad Kamran; Manjunath Basavarajappa; Nura Bala; Leila Hashemian. Laboratory evaluation of stabilized base course using asphalt emulsion and asphaltenes derived from Alberta oil sands. Construction and Building Materials 2021, 283, 122735 .
AMA StyleFarshad Kamran, Manjunath Basavarajappa, Nura Bala, Leila Hashemian. Laboratory evaluation of stabilized base course using asphalt emulsion and asphaltenes derived from Alberta oil sands. Construction and Building Materials. 2021; 283 ():122735.
Chicago/Turabian StyleFarshad Kamran; Manjunath Basavarajappa; Nura Bala; Leila Hashemian. 2021. "Laboratory evaluation of stabilized base course using asphalt emulsion and asphaltenes derived from Alberta oil sands." Construction and Building Materials 283, no. : 122735.
Asphalt binder comprises four main fractions—asphaltenes (A), saturates (S), aromatics (A), and resins (R)—referred to as “SARA”. Asphaltenes plays an important role in determining the linear viscoelastic behavior of asphalt binders. In this research, asphaltenes are added as a distinct modifier to improve the performance properties of asphalt binder. The modified binders are aged using a rolling thin film oven. A dynamic shear rheometer is then used to measure the rheological properties of the binders at high temperatures. Changes in the chemical composition of the modified binders are also studied through the determination of SARA fractions, using precipitation and gravity-driven chromatography methods. The rheological results show that asphaltenes improve the stiffness and elasticity of asphalt binder. It is also shown that the addition of asphaltenes raises the high Performance grade (PG) temperature of the asphalt binder, with every 6% of asphaltenes added resulting in a one-interval increase in high PG temperature grade. SARA analysis shows that the increase in polar fraction content due to the addition of asphaltenes causes the stiffness, elasticity, and viscosity of asphalt binders to increase. The results indicate that asphaltenes are an effective yet inexpensive additive to improve asphalt binder properties at high temperatures.
Amirhossein Ghasemirad; Nura Bala; Leila Hashemian. High-Temperature Performance Evaluation of Asphaltenes-Modified Asphalt Binders. Molecules 2020, 25, 3326 .
AMA StyleAmirhossein Ghasemirad, Nura Bala, Leila Hashemian. High-Temperature Performance Evaluation of Asphaltenes-Modified Asphalt Binders. Molecules. 2020; 25 (15):3326.
Chicago/Turabian StyleAmirhossein Ghasemirad; Nura Bala; Leila Hashemian. 2020. "High-Temperature Performance Evaluation of Asphaltenes-Modified Asphalt Binders." Molecules 25, no. 15: 3326.