Feasibility of Vacuum Decompression Capillary Method for Measuring the Dynamic Viscosity at 60°C of SBS Modified Asphalt

In order to study the applicability of the vacuum decompression capillary method in testing the dynamic viscosity of SBS modified asphalt at 60°C, the effects of test equipment, test method, test environment, operator’s manipulation, and capillary calculation constant on the dynamic viscosity test results of SBS modified asphalt at 60°C were compared and analyzed. The test results show that, when all other factors were well controlled, the repeatability errors were 12.4% and 61.4%, which is far from satisfying the requirement (≤7%), and the reproducibility error was far from satisfying the requirement of no more than 10%. The coefficient of variation of the test results varied from 19.1% to 63.4%, indicating that the test results could not guarantee the accuracy of the test, and it is not suitable to be a test method for dynamic viscosity of SBS modified asphalt at 60°C.