Rotation shear stress relaxation test device for asphalt mixture and method

Abstract

A rotation shear stress relaxation test device for an asphalt mixture and a method, belong to a mechanical property test technology field of the asphalt mixture. The device is composed of a test platform, a loading system, a temperature control system and a computer control system, wherein the loading system comprises a frequency converter (11), an electronic brake (12), a reduction box (25) and a micro motor (26), which can be controlled by a computer. The computer control system (1) can control the electronic brake (12) by the frequency converter (11) to implement rotation shearing loading, load holding and unloading that are stress relaxation test on an asphalt mixture test piece (6). The device and the method are suitable for determining stress relaxation performances of a common asphalt mixture, an SMA asphalt mixture, a regeneration asphalt mixture and other asphalt mixtures under different parameters, such as different temperatures, different strain levels, different loading, and different load holding time. When repetition frequency is set to be multitimes, and other test parameters such as unloading, load holding and stay time, are set, repeat stress relaxation test can be completed.

Description

technical field [0001] The invention belongs to the field of testing the mechanical properties of asphalt mixtures, in particular to the test and measurement technology for the stress relaxation performance of asphalt mixtures. Background technique [0002] The stress relaxation of asphalt mixture refers to the characteristics of stress decay with time under the condition of constant temperature and strain. There are usually two evaluation indicators, namely stress relaxation time and stress relaxation modulus, which respectively reflect the stress relaxation rate of asphalt mixture. and stress relaxation capabilities. Asphalt mixture has viscoelasticity. At higher temperature, the stress will disappear quickly because of its strong relaxation ability. At lower temperature, the stress relaxation ability of asphalt mixture is poor and the relaxation speed is slow. Under the same temperature and strain conditions, the slower the stress relaxation rate of asphalt mixture, the ...

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Problems solved by technology

[0003] At present, the methods used for the stress relaxation test of asphalt mixture mainly include bending stress relaxation, compressive stress relaxation and direct tensile stress relaxation, etc. The stress relaxation test is realized by bending deformation, direct compression or tensile deformation respectively, while the rotational shear The stress relaxation test method of the loading mode has not been reported

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