Research On Properties Of Composite Modified Asphalt

Asphalt is a general election material in the road surface project, acting as a viscoelastic material. However, as it easily becomes brittle at low temperature and soft at high temperature, the application temperature range is narrow, the premature destructional phenomenon on the asphalt pavement takes place ever and again, so the research on the modified asphalt material is imperative under the situation. A lot of research proved that the utilization of polymer modified asphalt is an efficient approach to solve this problem. SBS modified asphalt has played an important role in the rapid development of highway, with its excellent properties. However, SBS modified asphalt is prone to being unstable during hot storage which present an obstacle to its development.This article bases on the internal and extrernal studies, aiming at the premature destructional phenomenon of asphalt pavement in Hebei province, asphalt was modified by utilizing SBS, the conventional properties and storage stability variable law of SBS modified asphalt. And in allusion to the characteristic of bad storage stability of SBS modified asphalt, in order to decrease the density differences and increase the consistency between SBS and asphalt, the built modified asphalt were obtained by adding the silica hydrated and metallic soap into SBS modified asphalt, the optimal content can be determined and the SBS modified asphalt with high-temperature storage stability can be gained, but the precondition is that the original performance is hardly effected. The microstructure of modified asphalt was analyzed by fluorescence microscope.The results showed that the SBS modified asphalt had the properties of high-temperature behavior, low-temperature performance, and sensitivity for temperature, but the storage stability was not well; the storage stability, high-temperature behavior and sensitivity for temperature of SBS modified asphalt were improved by silica hydrated and metallic soap in a different degree, the improved effect on its storage stability by metallic soap was better than that by silica hydrated, however, they had a bad effect on the low-temperature performance.