CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Qun Lu,Aimin Sha,Wenxiu Jiao,Ke Shi,Ze Peng,Ruimeng Song
In response to the growing demand for energy-efficient and sustainable materials in road construction, this research presents a pioneering method to enhance the engineering application of bio-oil rejuvenated asphalt . Initially, aged asphalt was rejuvenated by blending with 6% castor oil . Subsequent modifications included introducing varying concentrations of polyphosphoric acid (PPA) (0%, 0.5%, 1.0%, 1.5%), combined with differing sulfur levels (15% and 30%). The rheological properties of the resulting asphalt binders were assessed using rotational viscometer (RV), asphalt binder crack device (ABCD), and dynamic shear rheometer (DSR) tests, while fourier transform infrared spectroscopy (FTIR) test was employed to reveal the interaction mechanism. The study’s key findings reveal that incorporating 15% sulfur significantly reduces asphalt viscosity , effectively lowering the mixing and compaction temperatures by approximately 17 °C and 15 °C, respectively. Besides, rutting factor ( G * / sin δ ) and fatigue life ( N f ) results unveil a positive connection between PPA content, high-temperature stability, and fatigue resistance. Furthermore, the grey relational analysis emphasizes a strong correlation between G * / sin δ and R 3.2 (grey relational degree of 0.986), indicating that the recovery rate partially reflects high-temperature performance. The FTIR analysis demonstrates that bio-oil primarily contributes through physical blending, whereas PPA undergoes chemical transformations, and the combination of sulfur with asphalt results in both physical and chemical reactions. In conclusion, this research emphasizes the synergistic potential of bio-oil, sulfur, and PPA in enhancing recycled asphalt performance. For optimal warm mix efficiency and road performance, incorporation of 15% sulfur and 1.0% PPA in bio-rejuvenated asphalt is recommended. These findings provide substantial advantages in reducing reliance on petroleum asphalt and mitigating carbon emissions , contributing to sustainable infrastructure development.
研究领域:
土木工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2022
·Vol. 9
·期 6
·065304
·
IF 2.025
Min Dai,Chang-ming Chen,Zhan Wang,Wen-hao Pan,Xiao-wei Sun,Ning Tang,Li-mei Wu
The performance of asphalt mixtures containing reclaimed asphalt pavement (RAP) are strongly influenced by the degree of blending between RAP and virgin bitumen. In the aim of revealing the blending interface, the present work reports an experimental investigation on the blending degree between modified bitumen and RAP (or aged bitumen). A montmorillonite-rhodamine composite modifier was prepared as a tracer, which has exclusive element and fluorescence. Using microscopic test technique, the blending process of and the crack process of RAP bitumen was observed, and the blending image of new reclaimed asphalt mixture was obtained. The interface was investigated through image processing and machine learning. Based on the results, the montmorillonite modifier slightly affected on the softening point and penetration of virgin bitumen after addition. The blending interface was engagement like gears. The optimal heating temperature range is 110 °C to 115 °C for forming a better adhesive interface between RAP and modified bitumen. Moreover, the interface transition zone thickness between RAP and modified bitumen was measured to be 4 to 8 μm.
研究领域:
材料科学
·
土木工程
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Qun Lu,Aimin Sha,Wenxiu Jiao,Ke Shi,Zhuosen Li,Yujing Chen,Peidong Du,Ze Peng,Ruimeng Song
In the realm of sustainable road construction, bio-oil has emerged as a promising and eco-friendly alternative for rejuvenating aged asphalt. Nevertheless, challenges arise due to poor stability, diminished performance at elevated temperatures, and limited anti-aging properties. This study introduces an innovative approach by blending biochar, obtained from the pyrolysis of waste coffee grounds, into bio-oil to create a composite modified regenerator. Initially, the study conducts a microscopic characterization of the biochar using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Subsequently, the rheological properties of this composite rejuvenated asphalt are evaluated across low, moderate, and high-temperature ranges using bending beam rheometer (BBR), linear amplitude sweep (LAS), and multiple stress creep and recovery (MSCR) tests. Departing from the traditional emphasis on initial property restoration, it further delves into performance alterations after re-aging of rejuvenated asphalt through temperature sweep (TS) and Fourier transform infrared spectroscopy (FTIR) tests, providing a comprehensive assessment of the anti-aging characteristics of rejuvenated asphalt. Additionally, gel permeation chromatography (GPC) is employed to quantitatively analyze the changes in asphalt molecular weight distribution. The microscopic characterization reveals the development of a rough and porous structure within the biochar, facilitating enhanced adhesion and interaction between the rejuvenator and the asphalt binder. Moreover, bio-oil rejuvenated asphalt exhibits excellent low-temperature crack resistance and moderate-temperature fatigue resistance. Following the incorporation of biochar, notable enhancements in high-temperature rutting resistance and anti-aging properties are observed, validating the efficacy of the biochar with bio-oil composite modified regenerator. To achieve optimal performance outcomes, a biochar content of 6 % (as a proportion of aged asphalt), corresponding to a 1:1 ratio of biochar to bio-oil, is recommended. Under this condition, the properties of the composite modified rejuvenated asphalt demonstrate comparability to those of the original asphalt. In summary, this research underscores the potential for integrating waste coffee biochar material into infrastructure development, thereby promoting circular economy principles and advancing more sustainable construction practices.
研究领域:
土木工程
·
可持续材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）