Mohammad Amin Ganjei - Civil and Environmental Engineering Department, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Esmail Aflaki - Pavement Lab., Civil and Environmental Engineering Department, Amirkabir University of Technology, Hafez Street, Tehran, Iran

Nano particles include some specific properties such as a high specific area and present an inherent potential to improve bonding of bitumen materials. Nowadays, the technology of producing nano-sized particles is developing and the application of them in various aspects of civil engineering is becoming more cost effective. In this study, the effect of some parameters such adding nano SiO2 particles on improving of Self-Healing asphalt concrete were investigated using the Taguchi method. To simulate traffic-damaging loads and to determine the Healing Index (HI), Superpave Indirect Tensile Fatigue Tests (IDT) was applied in a system with two phases; damage and healing. For all specimens, an IDT test was carried out which led to the creation and propagation of micro cracks until reaching specific damage level (20% decreasing resilient modulus). Next, the specimens were unloaded (the healing phase; recovering resilient modulus) and during two phases the resilient modulus was measured. The Healing Index (HI) was introduced using the resilient modulus variation.

nano SiO2, Healing Index, Taguchi method, hot mix asphalt, resilient modulus