Systematic tests of the performance of asphalt mixtures of different gradations and asphalt content have been carried out. The following characteristics of the asphalt mixture were analysed: (1) high temperature rutting, (2) resistance to cracking at low temperature, (3) moisture stability, (4) fatigue resistance, and (5) skid resistance. The results of these and previous studies have enabled the authors to establish a system of proportioning asphalt mixtures that are suitable for application in the various climate areas of China. The recommended optimal proportions of asphalt mixture for each of the climate areas are also presented. High temperature rutting is taken as the control factor for climate areas where the yearly extreme low temperature is higher than minus 21.5 degrees Celsius and the average maximum temperature in July is higher than 30 degrees Celsius. Low-temperature cracking is considered as the main control factor for climate areas where the yearly extreme low temperature is lower than minus 21.5 degrees Celsius and the average maximum temperature in July is lower than 30 degrees Celsius. For the remaining climate areas, both low-temperature cracking and high-temperature rutting of asphalt mixture are taken as control factors. (a) For related work by these authors see ITRD 490912 and 897066.
Samenvatting