Prediction of Maximum Pavement Surface Temperature Using Maximum Air Temperature and Latitude

Master's Thesis from the year 2019 in the subject Engineering - General, Basics, grade: Excellent, , course: Raod and Transport Engineering, language: English, abstract: Marshall Mix design was developed for the hottest pavement surface temperature of the USA, which is 60-degree Celsius. This design mechanism is very dominant in our country. It was directly adopted without any modification. The research aims to develop a prediction model that will be employed to modify the Marshall Mix design method for the Ethiopian climate and incorporate maximum pavement surface temperature.

In order to do so, ten years historical air temperature of Ethiopia, taken from the National Metrology Agency which was used to determine the hottest month for onsite measurement of 24 towns. For each town, actual maximum pavement surface temperature was measured from August 2016- February 2018, using Nanosensor/ radiator thermometer. The countries climate was classified into four climatic regions for the purpose of this research. For each region, a representative town is incorporated on the study.

Based on site measurement and maximum air temperature with the associated latitude, Multivariate Regression Model was selected. To select the model R-squared value method, an excel analysis of scatter plots and collinearity of the explanatory variables was checked. All the inputs were provided to STATA SE-13 statistical software and model developed. After the model was developed by all the 24 towns' data, it was validated and cross-validated by dividing the data into 5 folds in order to make it applicable for all scenarios. The model was further elaborated in a laboratory case study, for the hottest town of Samara, Afar region capital. Mix design was prepared at 60°C, which is the standard specimen heating temperature and at 75°C, which is the actual maximum pavement surface

temperature of Samara town. The mix that was prepared at 60° C, found to fulfill all the criteria's of Marshall Mix design outlined by Asphalt Institute for heavy Traffics. Whereas, at 75°C, it fails to do so. Therefore, mix design should be conducted at the place maximum pavement surface Temperature rather than conducting at the standard 60degree Celsius.