Moisture Damage Assessment of Asphalt Mixture using Eatons Reagent

Abstract

Abstract: The main purpose of this research work was to create a correlation model called a moisture damage index, that could predict moisture damage probability in both qualitative and quantitative test regimes. To determine the effect on moisture damage of asphalt mixture, chemical-based modifiers and single aggregate sources, such as calcium carbonate, were selected. Eaton's Reagent, i.e., Phosphorous Pentoxide in Methane Sulphonic Acid, is used to make modified bitumen in this research. Eaton's Reagent is made in a laboratory with a 1:10 synthesis formula and a unique technique. Base binders are changed with varied amounts of Phosphorus Methyl Compound (PMC) by weight of optimum binder content i-e 0.25%, 0.50%, 0.75% & 1.00%. To establish a moisture damage index, the dosage of Eaton's Reagent was optimised using both qualitative and quantitative measurements. This reagent interacts strongly with the asphaltene fraction of bitumen rather than the maltenes portion, resulting in a higher service temperature than the base binder. Asphalt mixtures were prepared and tested using performance testing to verify the effect of phosphorous methyl compound on their performance. The boiling water test was simple to administer and took less time, while the rolling bottle test was found to be more reliable than other qualitative tests. Although Marshal stability was easy to perform in quantitative tests, while the Hamburg wheel track test were shown to be more effective in determining moisture susceptibility with a reasonable level of confidence. A testing regime compromises of qualitative as well as quantitative tests to ascertain relative accuracy of each test on moisture damage. Keywords: Eaton’s Reagent; Asphalt mixtures; Loss of adhesion; moisture damage; limestone