Study On Preparation And Properties Of Montmorillonite Modified Asphalt Mixture

Road asphalt materials were widely used in road construction for the unique physical and rheological properties, but the attenuation of its performance was serious for its direct contact with all kinds of bad environment of the nature, including light, rain water, oxygen and wheels under repeated load which lead to all sorts of diseases of the road pavement appear and restricted of construction development of the economical and long life road.In this paper, montmorillonite was used to modify the common matrix asphalt to improve its durability, lower road asphalt performance attenuation amplitude, reduce the pavement diseases occur and extend the service life of the road. During the preparation of montmorillonite modified asphalt, high-speed shear mixing and ultrasonic dispersing fusion process was adopted to strengthen the asphalt with montmorillonite in molecular level of intercalating fusion; the change of the physical and rheological properties was tested on the modified asphalt and asphalt before and after aging, including penetration, softening point, ductility and viscosity test, temperature scanning test, the frequency scanning test, fatigue test, etc. Asphalt mixture specimen was producted and tested the water stability of performance, high temperature performance, low temperature performance and fatigue performance.Results show that the use of ultrasonic dispersion instrument can improve the fusion effect between asphalt and montmorillonite better compared with the high shear emulsifying machine. Physical performance and rheological test results shows that the viscosity and elasticity of montmorillonite modified asphalt can be improved obviously, viscosity can be increased more evident under the high temperature, meanwhile fatigue performance of asphalt have obvious improvement; Asphalt contrast test results before and after aging Show that asphalt has good anti-aging performance and the attenuation rate is smaller; asphalt mixture test results of also show that modified asphalt mixture has high aging resistance, fatigue resistance and good heat stability. So adding the montmorillonite modifier can improve the durability and fatigue resistance performance of asphalt pavement and reduce rutting and other road diseases.