Effects of Aging on the Physical and Rheological Properties of Trinidad Lake Asphalt Modified Bitumen

Abstract

The application of various modifiers has emerged in recent years to improve conventional petroleum-based bitumen properties. The natural asphalt called Trinidad Lake Asphalt (TLA) has been applied very often due to its consistent properties, high viscosity and density, and superior rheological properties, and effective blending with other bitumen. However, most studies on TLA-modified binders always focused on physical and rheological properties in the original (unaged) condition, but the details about aging properties are often neglected. This study aimed to investigate the effect of short-term aging on the physical and rheological characteristics of the 35/50 base bitumen modified by the addition of two different TLA contents. The conventional physical tests and dynamic shear rheological tests were undertaken before and after aging to measure the penetration and softening point, complex shear modulus, and phase angle of the modified binders, as well as to calculate the zero shear viscosity using the Cross model fitting procedure. Based on the results of the above-mentioned comprehensive testing, the effect of aging on TLA-modified binder properties was evaluated using aging indices, as well as a direct comparison of results. The tests revealed that the short-term aging of TLA-modified binders did not worsen or reduce the pavement resistance to permanent deformation or the load-bearing capacity of the asphalt mixture.

The Influence of Zero Shear Viscosity of TLA-Modified Binder and Mastic Composition on the Permanent Deformation Resistance of Mastic Asphalt Mixture

“…The additional results of a comprehensive laboratory investigation on the physical and rheological properties of the 35/50 base bitumen modified by the addition of three different TLA contents (0, 10, and 20% by weight) as well as on the effect of short-term ageing on these physical and rheological characteristics were presented by the authors elsewhere [ 55 , 56 ].…”

“…The result of fitting ZSV to the static indentation is about 95%, the slightly worse relationship can be observed using the regression results for the dynamic indentation (90%). It is worth emphasizing that the authors carried out similar estimations for other test conditions: the TLA-modified binders in the original (unaged) state, creep test of ZSV instead of oscillatory test and three temperatures of ZSV test in the range of 40–60 °C [ 55 , 56 ]. The analysis revealed that not one of these considered test conditions had a significant influence on the static as well as dynamic indentation test results.…”

On the Use of Recycled Asphalt and Trinidad Lake Asphalt (TLA) for the Preparation of High Modulus Asphalt Concrete

“…Secondly, TLA contains about 54% bitumen, 36% minerals and 10% other useful substances. The minerals are very small, 90% of the minerals have a particle size of less than 0.075 mm [22], and the aged bitumen in RAP is also relatively hard, both of which can improve the softening point and wear resistance of the asphalt. Finally, both RAP and TLA can increase the thickness of the asphalt mold and increase the friction coefficient of the road surface.…”

Study on Aging Mechanism and High-Temperature Rheological Properties of Low-Grade Hard Asphalt

“…Studies conducted by Li [ 11 ] and Cao et al [ 12 ] demonstrate the impact of RTFOT, PAV, and UV aging tests on the fundamental properties of asphalt. Several researchers argue that analyzing the high-temperature performance of asphalt through its rheological properties is more scientifically rigorous [ 13 , 14 ]. The dynamic shear rheological (DSR) test is utilized to investigate the high-temperature rheological properties of asphalt, while the rutting factor (G*/sinδ) serves as an indicator for evaluating its high-temperature performance [ 15 , 16 ].…”