Method for processing and analyzing multi-sequence dynamic creep test data of asphalt mixture

Abstract

The invention discloses a method for processing and analyzing multi-sequence dynamic creep test data of an asphalt mixture. Creep data measured by test undergoes low-pass filtering by designing a Butterworth low-pass filter to obtain a smooth creep curve, the average permanent strain rate of every loading sequence is calculated, and the following three indicators for evaluating the creep characteristics of the asphalt mixture are calculated according to a formula: the strain rate sensitivity index SRSI, the composite average permanent strain rate CAPSR and the composite creep stiffness modulusCCSM, wherein the influence of the stress condition on the creep of the above material is positively correlated with the value of the SRSI; the CAPSR represents the equivalent strain rate under various complex stress conditions, the permanent strain generated in one-time loading of the material is positively correlated with the value of the CAPSR, and the high temperature performances of the material are negatively correlated with the value of the CAPSR; and the CCSM represents the resistance of the material to permanent deformation at the end of the creep test, and the high temperature performances of the material are positively correlated with the value of the CCSM.

Description

technical field [0001] The invention relates to a multi-sequence dynamic creep test data processing and analysis method for asphalt mixture, which belongs to the field of road maintenance. Background technique [0002] The dynamic creep test recommended by the NCHRP research program in the United States is an indoor test widely used to explore the high-temperature creep characteristics of asphalt mixtures. The test uses half-sine wave pulse loading, which is considered to be the closest to the actual vehicle load on the road. , the rheological number proposed based on this test is a widely used index to evaluate the high-temperature performance of asphalt mixtures. Many scholars have proposed some improved versions of the test based on the test, such as the multi-stage loading creep test based on the axial load spectrum, the uniaxial penetration dynamic creep test, etc., and the improved test still uses the rheological number or composite The rheological number is used to e...

AI Technical Summary

Problems solved by technology

However, because the traditional dynamic creep test often only adopts a single load action form in one test, that is, one test can only obtain the strain rate under one loading condition, if the strain rate under multiple stress conditions is to be obtained, then Multiple experiments are required, which greatly increases the workload and the difficulty of post-data processing

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