Determination of Temperature Zoning for the Great Lakes Region of Africa Based on Superpave System

Abstract

"Majority of the countries in the Great Lakes region of Africa still rely on the traditional Penetration grading approach for characterizing asphalt binder, as opposed to the more recent and reliable approach of SuperPave (Superior Performing Asphalt Pavements). This paper outlines the steps and criteria of selecting Performance Grade (PG) of bitumen to be used in selected countries of the Great Lakes region, based on the SuperPave approach. In Superpave, high-temperature (HT) Performance Grade required for a given region of project is determined based on a rutting damage model. HT equation is a function of layer thickness, climatic conditions, and latitude of the site (Mohseni et al, 2005); whereas, Low-temperature (LT) Performance Grade is selected using an algorithm developed from LTPP climatic data, and that relates the minimum pavement temperature to minimum air temperature, latitude, and depth (Mohseni, 1998). Study of climatic conditions of selected countries (Uganda, Kenya and Tanzania) in the great lakes region shows that the maximum pavement design temperature is 64 ºC, while the minimum pavement design temperature is -10 ºC. Further, the temperature zoning is distributed into three geographical areas, namely PG 64-10, PG 58-10 and PG 52-10 according to the collected and studied data."