COMPARING FACTORS AFFECTING RESILIENT MODULUS IN ASPHALT MIXTURES

The present study attempts to investigate di erent factors a ecting the resilient modulus of hot mix asphalt. So a fractional factorial analysis of experiment was carried out considering ve factors, each at two di erent levels. These factors were the maximum nominal aggregate size, specimen diameter and thickness, the load pulse form and duration. During the course of analysis, two types of hot mix asphalts with di erent maximum aggregate sizes were taken into consideration, while Marshall compaction method was used to prepare the specimens. Furthermore, measuring the resilient modulus, sinusoidal and triangular load pulse forms were applied. Finally, our investigation examined the di erent factors interrelations which a ect the resilient modulus. Analysis of the factorial experimental design showed that the maximum nominal aggregate size was the most important factor a ecting the resilient modulus, then the load duration, the specimen geometry (thickness and diameter), and nally the interactions between the di erent factors. Keyword: Resilient modulus; Specimen's geometry; Load factors; Factorial experimental; Asphalt mixtures.