Asphalt mixture dynamic modulus testing method

Abstract

The invention discloses an asphalt mixture dynamic modulus testing method comprising the steps that: 1, with an asphalt mixture rotation compaction instrument, an asphalt mixture sample is formed; and through cutting, an asphalt mixture cylindrical sample with a fixed size is obtained; 2, two pressure heads are prepared; the sample and the two pressure heads are plated into an environment box with a target temperature; and the temperature is maintained for 5h; 3, the two pressure heads and the sample are fetched; the two pressure heads are respectively placed at central positions on two ends of the cylindrical sample; and sinusoidal axial compressive stress is applied to the sample with different frequencies under a specified test temperature; and 4, during the loading process, applied stresses and generated axial strains at corresponding times are determined, and the dynamic modulus is a ratio of the amplitude of sinusoidal load to the amplitude of generated sinusoidal strain. According to the method provided by the invention, with the local loading test, lateral restraint of the asphalt mixture in an actual pavement can be effectively simulated. The test device is simple, the operation is easy, and the method can be popularized.

Description

technical field [0001] The invention belongs to the field of mechanical performance testing of asphalt mixture Background technique [0002] The dynamic modulus test in the US Simple Performance Test (SPT) cannot simulate the lateral restraint of actual asphalt pavement. However, the presence or absence of lateral constraints has a great influence on the deformation characteristics of the mixture, and the presence of lateral constraints can more realistically simulate the actual situation. Only tests that can simulate the actual pavement asphalt mixture confining pressure state (lateral restraint) can obtain accurate mechanical parameters. In the SPT dynamic modulus test, a constant confining pressure is applied to the specimen through a closed triaxial chamber. The lateral constraints in the actual pavement will change due to the performance of the asphalt mixture, the magnitude of the load and the change of temperature, so imposing a fixed lateral confining pressure is o...

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Problems solved by technology

Moreover, the SPT dynamic modulus test equipment has high requirements and complicated operation, which is not conducive to popularization and use.

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