Investigating the Effect of Different Additives on the Mechanical Properties of Cold Asphalt Produced with Emulsion Bitumen

Some of the important benefits of cold asphalt include conservation of natural resources, cost and energy reduction. Meanwhile, warm asphalt mixtures have higher durability and resistance than cold mixtures, but the use of hot asphalt mixtures causes environmental pollution, the release of toxic and harmful gases, and also reduces the safety of workers. Therefore, today, the use of cold asphalt mixtures is increasing in order to protect the environment and also work risks, which is used with this type of asphalt along with emulsion bitumen. However, the use of cold asphalt produced in factories with emulsion bitumen leads to problems such as rutting, thermal cracks, reduction in strength, etc. Therefore, the need to use additives in order to improve the functional characteristics of this type of asphalt is felt. Considering the importance of the subject, in this research, a review of the studies conducted in the field of the effect of different additives on the functional characteristics of recycled cold asphalt produced with emulsion bitumen has been done. Finally, according to the results of the studies, it can be said that asphalt mixtures produced with emulsion bitumen have very low resistance to environmental factors and humidity, and therefore the use of additives is recommended. The results showed that the use of different additives improves the resistance of the asphalt mixture against moisture, which is more evident in the samples modified by combining polymer with cement and polymer with lime than other additives. shows. Also, due to creating a three-dimensional network in the bitumen and actually reinforcing the bitumen, polymer materials can increase the asphalt resistance and Marshall endurance.