Comprehensive Performance Evaluation and Cost Analysis of SBS-Modified Bioasphalt Binders and Mixtures

Abstract

Developing new sustainable materials such as bioasphalt has become a research trend in recent years. In this study, bioasphalt modified with the addition of styrene-butadiene-styrene (SBS) was investigated to research whether it can replace petroleum asphalt binder of 50 penetration grade (50#) in road performance at a lower price. A series of laboratory tests were carried out to evaluate the performance of SBS-modified bioasphalt binders and mixtures, including penetration, softening point, ductility, rutting, moisture susceptibility, and low-temperature cracking. The SBS-modified bioasphalt was prepared with different of bio-oil content: 0, 5, 10, 15, and 20%. Moreover, a comprehensive evaluation was applied to all types of asphalt and a recommended selection of asphalts was provided. The research showed that the performance of SBS-modified bioasphalt could satisfy the specification requirements of 50# base binder when bio-oil concentration was less than 15%. The high-temperature stability of SBS bioasphalt mixture was worse than that of the 50# base binder mixture to some degree, but could still satisfy the specification requirements. The SBS-modified bioasphalt mixture had better thermal crack resistance and water stability than the 50# base binder mixture, and it had better adhesion at low temperatures, reaching its maximum adhesion value with an aggregate loss of 4.33% when the bio-oil content was 10%. The SBS-modified bioasphalt with 10% bio-oil (S110) is thus recommended according to the performance evaluation and cost analysis. Furthermore, from the standpoint of environmental protection and economic benefits, S110 has good development prospects.