مينا خدايي

Researchers in various fields are currently striving to develop methods and technologies that can utilize waste and by-products as substitutes in construction and road maintenance industries. These efforts are aimed at reducing environmental impacts. Researchers have investigated the use of steel slag and construction waste as potential alternatives to natural aggregates in asphalt mixtures. In these studies, the possibility of partial or full use of these alternative materials in asphalt mix production has been examined. Due to its high surface area and mechanical properties such as hardness, roughness, and resistance to wear, steel slag is increasingly used in construction and road maintenance processes. The use of steel slag aggregates (SSA) as a substitute for natural aggregates in asphalt and cement road construction can lead to a reduction in environmental damage. In this study, coarse steel slag with replacements of 50% and 100% for coarse aggregates and fine steel slag with replacements of 25% and 50% for fine aggregates, along with various combinations of these dimensions (100% coarse and 25% fine, 100% coarse and 50% fine, 50% coarse and 25% fine, 50% coarse and 50% fine), were used in SMA asphalt mixtures. In order to achieve the best performance of these mixtures, suitable amounts of steel slag in coarse and fine dimensions were obtained in this research through simultaneous analysis of performance test results using the balanced mix design method. Dynamic creep test was used to determine the rutting resistance of the mixture, indirect tensile test for eva‎luating the moisture sensitivity of the mixture, Illinois flexibility index test, and indirect tensile splitting test for assessing the cracking of the mixture at intermediate temperature and fatigue based on the fatigue were employed. The results of the performance tests were within the acceptable range of the balanced mix design, and it was shown that adding steel slag increased resistance to cracking at intermediate temperatures. It also improved the rutting resistance of the mixture. Resistance to moisture damage with the replacement of 50% coarse aggregate alone did not result in a significant change, but with its increase, resistance to moisture sensitivity in this mixture decreased. However, with the replacement of fine steel slag alone, resistance to moisture sensitivity improved. In the end, the mix design with a combination of 100% coarse steel slag and 50% fine steel slag showed the best performance in SMA asphalt mixtures.

سرباره فولادي , آسفالت با استخوان بندي سنگدانه ايي , طرح اختلاط متعادل , آزمايش شاخص انعطاف پذيري ايلينوي , آزمايش ترك كششي غير مستقيم

Steel Slag , SMA Asphalt , balanced mix design , Illinois Flexibility Index (I-FIT) , Indirect Tensile Splitting Test (IDEAL-CT)

Mina Khodaei

Dr. Mahmood Ameri