Polymer chemically-modified asphalt composition capable of being stably stored at high temperature and preparation method thereof

The invention relates to a high polymer chemically-modified asphalt composition and a preparation method thereof. The preparation method comprises the following steps: chemically modifying rubber, elastomer and base asphalt, and additionally matching stuffing and processing aids; premixing the materials by high polymer processing equipment to prepare the master batch of the modified asphalt; and fully dispersing the master batch into the asphalt by a high-speed shear mixer or by mechanical stirring. Or the modified asphalt material can be prepared by firstly pre-preparing a viscous liquid mixture of modified asphalt and then stirring and mixing the viscous liquid mixture of modified asphalt with the base asphalt. The modified asphalt material prepared by the invention has stable storage performance at high temperature, good performance at high temperature and low temperature, stable processing and preparation and simple and convenient method, and not only can be directly used in factory production but also can be used for road laying sites and in the construction of waterproofing materials.