Stripping resistance of asphalt concrete Based on Physico-chemical characteristics

Regarding prominence of Physico-chemical characteristics of steel slag in comparison with natural aggregates in road construction applications, it is necessary to survey the characteristics in detail and accurately. Therefore, the purpose of this study is a comparison of mineralogical and moisture absorption characteristics between steel slag and natural aggregates. The specimens were obtained from basic oxygen furnace (BOF) slag and limestone. X-Ray Diffraction (XRD) method was applied to determine the mineralogical characteristics of specimens, while FT-IR test was employed to study the moisture absorption of samples. Moreover boiling water test and three types of tests on compacted mixture including Indirect tensile strenght, Resilient modulus and Marshall Stability tests were performed according to ASTM D4867 to evaluate moisture susceptibility of mixtures. The XRD test results show that steel slag has several peaks results from a complex structure and many minerals in the specimens. The results of FT-IR test indicate that the amount of moisture absorption of asphalt mixes prepared with steel slag aggregates are less than that prepared with limestone. As a result, steel slag has a better stripping resistance than limestone in asphalt mixes.

Keywords:

Steel slag , Asphalt concrete , Stripping , XRD , FT-IR , Resilient modulus