Evaluating the Effect of Lucobit on Moisture Susceptibility and Mechanical Performance of Bitumen and Asphalt Mixtures

Abstract

The use of polymer in hot mix asphalt production has remarkably in recent decades. Destruction due to moisture in hot mix asphalt is of basic matters about flexible pavement durability. In recent decades different ways have been used to evaluate moisture Sensitivity of HMA which some of them are simple with low cost and some are complicated with more reliable results. In this research the effect of polymer Lucobit on striping was investigated and boiling test and image processing technic and modified Lottman test that is the most popular test for moisture sensitivity were executed. Marshall Test, indirect tensile strength and dynamic shear rheometer (DSR), were done as additional tests. The results show that use of this polymer has a remarkable positive effect on moisture sensitivity and has improved other parameters of bitumen and hot mix asphalt. The results showed that 2%, 4% and 6% Lucobit, by which the PG 58-** will be upgraded to PG 64-**, PG 70-** and PG 76-**, respectively. In addition, the addition of 6% Lucobit has led to improvement of high temperature performance by 14.7 ºC and enhancement of three grades from PG 58-** to PG76-**. Also, the addition of 6% Lucobit has led to enhancement complex modulus by an average of 53.7 %.