Method for characterizing degrees of miscibility of old and new asphalt based on dynamic moduli of mixtures

Abstract

The invention relates to a method for characterizing the degrees of miscibility of old and new asphalt based on dynamic moduli of mixtures. The method includes the steps that various performance indexes of RAP materials, matrix asphalt, aggregates and mineral powder are tested; hot mixing regenerated asphalt mixtures and specimens are prepared according to a current regeneration norm; the dynamicmodulus of each specimen is tested and a principal curve of the actually measured dynamic moduli is drawn; asphalt mortars with different degrees of miscibility of the old and new asphalt are preparedby adding different addition amounts of old asphalt and regenerating agents into the matrix asphalt; DSR tests are carried out on the different asphalt mortars to measure composite moduli and phase angles of the asphalt mortars; the dynamic moduli of the mixtures with different asphalt mortar states is predicted and the predicted principal curve of the dynamic moduli is drawn; and the degrees ofmiscibility of the old and new asphalt in regenerated mixtures are characterized. According to the method for characterizing the degrees of miscibility of the old and new asphalt based on the dynamicmoduli of the mixtures, the method of performance indirect testing with the greatest controllability is selected for research, influences of mixing factors, human errors and mineral aggregate gradation are eliminated as far as possible, and the test precision is improved.

Description

technical field [0001] The invention belongs to the technical field of preparation of road building materials, and relates to a method for characterizing the miscibility of new and old asphalt based on the dynamic modulus of a mixture. Background technique [0002] At present, the characterization methods of the degree of miscibility of old and new asphalt are roughly divided into two types: macroscopic testing methods and microscopic testing methods. Law. These two types of methods have their own advantages and disadvantages. The microscopic test method is expensive and complicated to operate, and is mainly suitable for the study of the microscopic miscibility mechanism; the macroscopic test method is slightly less accurate, but the operation comparison method is simple, and can reflect the degree of miscibility from a macroscopic perspective. The effect of changes on the properties of the mixture. [0003] Karlsson and Isacsson marked the regeneration agent with polystyr...

AI Technical Summary

Problems solved by technology

However, this patent cannot test the real miscibility of old and new asphalt. On the one hand, the gradation of raw materials and the content of asphalt are not well controlled. On the other hand, the test results have large errors.

Images