A Simplified Odor Evaluation Method of Road Asphalt Materials

With the social economy gradual transforming to green and sustainable, the odor pollution in the process of road asphalt paving has become an environmental problem that cannot be ignored. In this study, GC-MS and gas detector are used for qualitative and quantitative analysis of volatile compounds produced by five asphalt materials. On this basis, combined with the odor threshold, the odor activity value (OAV) of each compound is calculated, and the odor of asphalt is analyzed by the method of the sum of odor activity value (SOAV), and the odor contribution of each compounds is classified according to the chemical properties to find the rule of odor contribution between each group. The results show that the main contribution groups of odor activity value of asphalt volatiles are alkanes, aldehydes, benzene series, and hydrogen sulfide. The evaluation process can be simplified on the basis of the existing odor evaluation: the concentration of each group is measured, and the sum value of the odor activity values of various asphaltenes is calculated by combining the odor threshold of each compound. Among them, the odor threshold of hydrogen sulfide does not need to be analyzed and can be obtained. Therefore, the odor threshold of alkanes, aldehydes, and benzene series in volatile compounds of different kinds of asphalt materials is further calculated, and the group odor threshold of three kinds of groups is finally determined. After determining the group odor threshold of the three types of groups, combining the concentration of alkanes, aldehydes, benzene series, and hydrogen sulfide, the sum value of the activity value of various asphalt odor is calculated and the error analysis is conducted with the measured value. It is verified that the odor characteristics of different kinds of asphalt can be analyzed by the simplified evaluation method of asphalt odor characteristics.