Asphalt exhibits Newtonian, non-Newtonian and viscoelastic behavior as the temperature is varied. This investigation reports the temperature at which asphalt exhibits non-Newtonian to Newtonian transition. Air blown, blended asphalt and petroleum pitch were tested at different aging conditions. The temperature at which the material exhibited shear rate independent viscosity was taken as the transition temperature. The transition temperature varied with processing method and aging conditions. It was seen that blended asphalt exhibited greater increase in apparent viscosity during aging when compared to air blown asphalt, whereas air blown asphalt showed greater shift in transition temperature for the same aging conditions. © 2011 Elsevier Ltd. All rights reserved.

Krishnan J Murali

Department Of Civil Engineering

A.Padma Rekha

AGING CONDITIONS

AIR BLOWN

Apparent viscosity

BLENDED ASPHALT

BLOWN ASPHALT

Experimental investigations

High temperature

NEWTONIAN-NON-NEWTONIAN TRANSITION

Newtonians

Non-Newtonian

PETROLEUM PITCH

Processing method

VISCOELASTIC BEHAVIORS

Asphalt

Non Newtonian flow

PETROLEUM TAR

Shear deformation

Temperature

Viscosity

Aging of materials

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Construction and Building Materials

Warm mix asphalt (WMA) technology is used to reduce mixing and compaction temperature of the binder; however, such addition is also expected to influence the rheological response of the binder during pavement service. This investigation is focused on WMA binders produced using Evotherm (Evotherm-VG30) and Sasobit (Sasobit-VG30) with a base binder (VG30). Shear rate sweep tests and steady shear tests conducted in the temperature range of 100-155°C indicate that the addition of Evotherm and Sasobit consistently reduce the viscosity of binder. This change in viscosity is found to be temperature and aging dependent. Short-term aged Evotherm-VG30 and Sasobit-VG30 binders exhibited increased shear thinning in the compaction temperature regime. Oscillatory shear tests and repeated creep and recovery tests were conducted in the temperature range of 15-75°C. The relationship between dynamic modulus and phase angle of WMA and VG30 binders followed Kramers-Kronig relations. Addition of Sasobit and Evotherm did not change the temperature regime associated with viscoelastic solid-fluid transition. From the creep and recovery test, addition of Evotherm and Sasobit resulted in increased strain during creep at higher temperatures. The influence of additives, especially Sasobit, on the base binder was found to be strongly temperature dependent. © 2018 American Society of Civil Engineers.

Journal of Materials in Civil Engineering

Rheological investigations on warm mix asphalt binders at high and intermediate temperature ranges

Fulltext

Procedia - Social and Behavioral Sciences

Effect of Mixing and Compaction Temperature on Dynamic Modulus of Modified Binder Bituminous Mixtures

Asphalt for highway and runway construction is processed by either air blowing or blending with different petroleum streams. In the blending process, petroleum pitch, a by-product of solvent deasphalting of the vacuum residue is mixed with heavy extract to produce asphalt of the desired specifications. The rheological response of blended asphalt hence depends to a large extent on the constitutive property of petroleum pitch. In an aim to develop robust models for blended asphalt, modeling the mechanical behavior of petroleum pitch hence becomes necessary. In this work reported here, petroleum pitch from crude sources such as Basrah Light, Arab Mix and Arab Light are subjected to steady shear for 99 min at temperatures ranging from 70 to 120 °C for different shear rates. Each of these material exhibited different stress overshoot and decay during steady shear depending on the temperature and shear rate. A viscoelastic fluid model of the rate type is selected to model the response of the material. Using the recent thermodynamic framework based on Gibbs potential proposed by Rajagopal and Srinivasa [27], restrictions on the proposed model are obtained. The rotational flow problem is solved and the material parameters are estimated. The model predictions are corroborated with the experimental observations and they are found to be reasonably good. © 2010 Elsevier Ltd. All rights reserved.

International Journal of Engineering Science

Characterization of petroleum pitch using steady shear experiments

Knowledge of the mechanical and thermodynamic behavior of straight run asphalt is desirable in view of its use as a binder for pavement applications. The different complex processes undergone by asphalt concrete mixtures such as healing, aging, etc. can be understood more clearly, if one has a better understanding of the constitutive behavior of asphalt. The need is pressing as the use of polymer-modified asphalt as a binder has increased in recent years. Most of the studies carried out on constitutive modeling of asphalt model pure asphalt either as a Newtonian fluid or as a linear viscoelastic fluid over a wide range of temperatures. The complexity related to the study of the constitutive behavior of asphalt is compounded by the fact that asphalt is a mixture of different chemical species some of which are amorphous and some of which are crystalline in nature. The relaxation mechanisms of asphalt are diverse with different relaxation mechanisms at different temperatures. In this study, we use a thermodynamic framework for the constitutive modeling of asphalt and we model asphalt as a material with multiple relaxation mechanisms. This framework recognizes the fact that materials like asphalt can exist in more than one natural configuration (for instance, stress free configuration). We use the experimental data available in the literature (Lethersich, W., 1942. The mechanical behaviour of bitumen. Journal of the Society of Chemical Industry 61, 101-108; Cheung, C.Y., Cebon, D., 1997. Experimental study of pute bitumens in tension, compression, and shear. Journal of Rheology 41 (1), 45-73) for asphalt from different sources and demonstrate the efficacy of the model. © 2005 Elsevier Ltd. All rights reserved.

Mechanics of Materials

On the mechanical behavior of asphalt

Properties of Portland cement-modified asphalt binder using Superpave tests

Fuel

Influence of heat and pressure treatment on the rheological behavior of petroleum pitches

Advances in Colloid and Interface Science

The colloidal structure of bitumen: Consequences on the rheology and on the mechanisms of bitumen modification

Experimental investigations on high temperature transition of asphalt

Journal	Data powered by TypesetConstruction and Building Materials
Publisher	Data powered by TypesetElsevier Ltd
ISSN	09500618
Open Access	No