| TLA (Trinidad Lake Asphalt) is one of the most famous natural asphalts in the world. It is produced in Trinidad Island in the South American with the good pavement performances. At present, the researches of TLA mainly focus on the applications of macro performances. Its micro aspects and modified mechanism are less studied. Therefore, the material properties, including mineral material (called ash) and asphalt material (called ETLA for short, i.e. extraction TLA), and the technical performances of TLA will be analyzed and studied through the relevant tests.1) The ash was researched in a systematic way by the grading analysis, the specific surface area test, X ray diffraction and other related micro tests, and 2 qualified mineral powders were chosen as comparison. The results show that the average particle size of ash is 7.66μm, the specific surface area is 16.24×104cm2/g, the minerals are (Ca4Al8Si8O32)·H2O18.664 and SiO2, namely its main composition is silicate volcanic ash. Through the experiments of Dynamic Shear Rheometer, it is found: at a temperature of 64℃and a ratio of filler to asphalt of 0.6, the G*/sinδof mortar containing ash is 1.74 times and 1.42 times of the 2 compared mineral powder mortars, respectively. When the conditions are changed, it also shows that the ash on the high-temperature performances of asphalt mortar is greater than the 2 compared mineral powder mortar's. According to the theory of gray analysis, it is found that the ratio of density, specific surface area, less than 0.01mm of content, average particle size and nonuniform coefficient impacted to the high-temperature performances of the asphalt mortar is: 0.910 : 0.880 : 0.859 : 0.431 : 0.369. All the relevant technical indexes and the performances of mortar show that the ash is better than the compared mineral powders.2) The ETLA and its mortar were researched by the tests of Thermal Analysis, Infrared Spectrum, Dynamic Shear Rheometer and so on, and 2 other matrix asphalts (TPK and ESSO) were made as comparisons. The results show that: compared with the 2 matrix asphalts, the ETLA have these advantages, including stronger molecule polar, more stability of molecular structure, better thermal stability and so on. In addition, the ETLA contains–S,–P and other bonds which is one of the reasons for its anti-aging. The testing with the Dynamic Shear Rheometer shows that the G*/sinδof ETLA is 30 times of TPK asphalt and 49.4 times of ESSO asphalt at a temperature of 64℃, respectively, so the ETLA has better high-temperature performances. At a temperature of 74℃and a ratio of filler to asphalt of 0.8, the G*/sinδof ETLA mortar is 39.9 times of the ESSO matrix asphalt mortar, so the high-temperature performances of ETLA mortar is obviously better than the matrix asphalt mortar's.3) The TLA modified asphalts were researched by the tests of the conventional tests, Thermal Analysis and Infrared Spectrum in a macro and micro way. The results show that: with the increasing of mixing amounts of TLA, the performances of high-temperature and anti-aging are improved, the thermal stability of modified asphalt are increased gradually, and the stability of molecular structure and the molecule polar are enhanced. In the TLA modified asphalt, the ratio of relational degree of ESSO, ash and ETLA is 0.97 : 0.73 : 0.80. The proportion of effect factor of ash impacting on high temperature performance is 29%.To concluding, the ash has a greater strengthened action to the TLA modified asphalt. The ETLA enhances the stability of molecular structure and the thermal stability for modified asphalts, so that the TLA will have a good performances of high temperature and anti-aging and so on. The performances of TLA modified asphalt under the integrative actions of ash and ETLA are made further improvement.
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