| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 257079 | Construction and Building Materials | 2015 | 7 Pages |
•Liquid antistrip (LAS), hydrated lime (HL), SBS and PPA were used in this study.•They were evaluated based on their effect on asphalt mix moisture susceptibility.•LAS and HL enhanced the asphalt mix resistance to moisture and fracture.•HL and SBS improved the rutting resistance.•PPA failed to improve the asphalt mix performance.
Moisture damage is a serious pavement distress that most transportation agencies face. It’s complicated mechanisms are dependent on several factors in asphalt pavement. This phenomenon triggers several pavement distresses, thus costing the country billions of dollars in pavement maintenance and rehabilitation. The most traditional technique adopted to mitigate moisture damage is adding selected additives or modifiers to asphalt mixtures. The additives and modifiers are used during construction to improve water resistance in asphalt pavement. However, each additive or modifier performs differently. This study evaluates the effects of two additives and two modifiers on the moisture susceptibility of two asphalt mixes. The additives include a liquid anti-stripping agent and hydrated lime while the modifiers include styrene butadiene styrene (SBS) and polyphosphoric acid (PPA). The effectiveness of the additives and modifiers was evaluated by conducting three mixture tests, including the Lottman AASHTO T283-02 test with five freezing and thawing (FT) cycles, the wheel-tracking test, and a fracture test using semicircular bending (SCB) specimens. The Lottman AASHTO T283-02 showed that adding liquid anti-strip to asphalt binder produced the best moisture resistance for both mixes followed by hydrated lime. The wheel track test showed that hydrated lime and SBS modifiers resulted in the least rut depth when used in both mixes. The results of the fracture test showed that liquid anti-strip and hydrated lime produced the highest fracture resistance. On the other hand, the three above test results indicated that PPA may not control asphalt mixers’ moisture susceptibility.
