高性能聚氨酯透水混合料关键性能研究

The implementation of permeable pavements on roads is an important step in the construction of a sponge city. The environment-friendly permeable pavement made of high-performance polyurethane bounded pervious mixture (PUPM) shows unique application values. In order to further clarify the key performance of PUPM, the mechanical, functional, and mesoscopic properties were compared with those of porous asphalt mixture (PA) through laboratory tests based on the current standards and specifications issued by the country and industry. The uniaxial compression test, uniaxial dynamic-creep test, low-temperature crack-resistance test, and water-stability test were conducted to evaluate the mechanical properties; the permeability test, anti-stripping performance test, and noise absorption performance test were carried out to evaluate the functional properties. Meanwhile, the indexes of air void content, equivalent radius, effective air void content, and tortuosity were utilized to investigate the internal structures using X-ray CT technology. The results show that the uniaxial compressive strength of PUPM is approximately 17 - 19 MPa at 20℃, and it exhibits distinguished deformation resistance, low-temperature cracking resistance, low-temperature load resistance, and water damage resistance when compared with PA. The functional test shows that the water permeability of PUPM is approximately four times that of PA. Moreover, PUPM shows more excellent anti-stripping performance under long-time polishing conditions, and exhibits significant noise-absorption performance. The air void content of PUPM is approximately 28% - 29%; the equivalent radius and the other void meso-structural indexes demonstrate non-uniform distributions along the height. Compared to PA, PUPM has a larger equivalent radius, effective void fraction, and tortuosity. To conclude, PUMP has better application prospects in the permeable-pavement constructions due to its excellent mechanical and functional properties.