Trinidad Lake Asphalt Research Articles

Characteristics of elastomeric and plastomeric binders in contact with natural asphalts

Bituminous binders are known to have simple rheological properties. Natural asphalts, such as Trinidad Lake Asphalt (TLA) and Uintaite, are often used for bitumen modification in order to obtain improved performance of the respective asphalt mixture (such as stiffness and deformation resistance). This paper presents the results from a series of assessments of ‘empirical’ and rheological properties of bituminous binders, which incorporate natural asphalts (specifically TLA and Uintaite) and/or polymer modifiers. Binder ‘empirical’ properties, measured by penetration and Ring and Ball softening point tests, showed that natural asphalts reduce or increase these respective “empirical” values at the level anticipated by “conventional blending formulas”. However, rheological analysis showed that the “stiffening” effect caused by addition of natural asphalts, which is normally anticipated in the case of asphalt incorporating unmodified bitumen, took place in a different way if a polymer modifier was also used.

Development of Heavy-Duty Mastic Asphalt Bridge Surfacing, Incorporating Trinidad Lake Asphalt and Polymer Modified Binders

ABSTRACT The mechanical properties of mastic asphalt are highly affected by the rheological properties of the respective mastic binder. Trinidad Lake Asphalt (TLA), which comprises naturally weathered bitumen and filler, is often used for modifying the mastic binder properties in order to obtain improved performance of the respective mastic asphalt mixture (such as stiffness and deformation resistance). Increased traffic loading and severe environmental conditions often demand more stringent requirements for the mixture performance; in these cases, further modifications of the mastic binder by polymer modification may be required. This paper demonstrates the potential use of polymer modified binders for mastic asphalt bridge surfacing for enhancing the mixture performance for use under more severe environmental conditions and/or to carry increased traffic loading. Rheological analysis showed that the “stiffening” effect caused by addition of TLA into mastic binder, which is normally anticipated in the case of conventional mastic asphalt (incorporating unmodified bitumen), took place in a different way if a polymer modifier was also used. Changes in rheological properties of different mastic binders were also reflected by changes in performance (such as low temperature strength, stiffness and deformation resistance) of their respective mastic asphalt mixtures.

Development of Heavy-Duty Mastic Asphalt Bridge Surfacing, Incorporating Trinidad Lake Asphalt and Polymer Modified Binders

ABSTRACT The mechanical properties of mastic asphalt are highly affected by the rheological properties of the respective mastic binder. Trinidad Lake Asphalt (TLA), which comprises naturally weathered bitumen and filler, is often used for modifying the mastic binder properties in order to obtain improved performance of the respective mastic asphalt mixture (such as stiffness and deformation resistance). Increased traffic loading and severe environmental conditions often demand more stringent requirements for the mixture performance; in these cases, further modifications of the mastic binder by polymer modification may be required. This paper demonstrates the potential use of polymer modified binders for mastic asphalt bridge surfacing for enhancing the mixture performance for use under more severe environmental conditions and/or to carry increased traffic loading. Rheological analysis showed that the “stiffening” effect caused by addition of TLA into mastic binder, which is normally anticipated in the case of conventional mastic asphalt (incorporating unmodified bitumen), took place in a different way if a polymer modifier was also used. Changes in rheological properties of different mastic binders were also reflected by changes in performance (such as low temperature strength, stiffness and deformation resistance) of their respective mastic asphalt mixtures.

Paving asphalt modifier from co-processing of FCC slurry with coal

Trinidad lake asphalt (TLA) is regarded as a high quality paving asphalt modifier for better road performance and has been used in many countries. However, the high price limits its application to only heavy load surfaces. A co-processing process of fluidized catalytic cracking slurry with coal was developed to produce heavy product (named CS) with asphalt modification ability similar to that of TLA. As a typical example, CS-modified asphalt with CS to base asphalt ratio of 20/80 meets the specifications of ASTM D5710 and BS 3690 for TLA-modified asphalt. The properties of CS-modified asphalt concrete are similar to that of TLA-modified asphalt concrete and satisfy the specifications of JTJ 036-98. Depended on the co-processing conditions used, the yields of the modifier are in the range of 65–80%, with softening point of 90–180 °C and penetration value of 0–8 (1/10 mm) at 25 °C. Asphaltenes content in CS is about 20–70 wt.%, preasphaltenes about 5–30 wt.%, and organic residues bout 5–60 wt.%. Hydrogen content and hydrogen distribution of CS vary with the co-processing conditions. The atomic ratio of H/C of CS is lower than that of TLA.

Aliphatic and alicyclic hydrocarbons isolated from Trinidad Lake asphalt

Aliphatic hydrocarbons isolated from the Trinidad Lake asphalt have been examined by gas chromatography and mass spectrometry. They appear to be unlike hydrocarbons recognized to be of biological origin and resemble synthetic mixtures. Possible explanations for their unusual character are considered and it is concluded that hydrocarbon mixtures exist in nature whose origin cannot be easily determined.