Desulfurized rubber (DR) and low-density polyethylene (LDPE) were used to modify bitumen. The basic physical properties, rheological properties, chemical composition, thermogravimetric behavior, and morphological characteristics were determined and evaluated to analyze the performance and mechanism of DR and LDPE compound-modified asphalt. A series of experiments (e.g., conventional test methods, rotational viscosity, storage stability, and dynamic shear rheometer tests), Fourier transform infrared spectroscopy, thermogravimetric analysis-differential scanning calorimetry, fluorescence microscopy, and atomic force microscopy were conducted. The results revealed that DR-modified asphalt (DRMA) had increases in the penetration, ductility, softening point, and penetration index by 30.2, 22.3, 3.5, and 11.1%, respectively, over the crumb rubber-modified asphalt (CRMA). The compatibility between the asphalt and modifier is better for DRMA than for CRMA. These findings indicate that DRMA has a better pavement performance than CRMA. Furthermore, compared with DR-modified bitumen, LDPE inclusions increased the value of G*/sin δ by at least 75.9% and improved the thermal properties. Morphological observations confirmed that the DR/LDPE additives were better dispersed than crumb rubber and formed a more homogeneous phase separation in the asphalt.

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As a kind of additional, waste slag may improve cement and concrete durability. However, the influence lies on the slag activity for several original waste slag. In this paper, the influence of activity for different original waste slag on the strength of slag cement was analyzed by using XPS (X-ray photoelectron spectrometer). The results showed that the order of slag cement strength prepared by different slag is T> H> C> J. The combination mode of silicon and aluminum in the waste slag microstructure greatly affect reactive quantity of slag powder, so that the cement strengths are obviously different. And the hydration activity of slag is more when silicon mainly exists in the form of oxide and aluminum mainly exists in the form of aluminates.