Synchronous test method for asphalt mixture dynamic stretching, compression modulus and Poisson's ratio

Abstract

The present invention discloses a synchronous test method for asphalt mixture dynamic stretching, compression modulus and Poisson's ratio. The method places the asphalt mixture split test piece in a split metal fixture of a loading test system, installs a horizontal radial displacement sensor and a vertical radial displacement sensor on end surface of the test piece, and applies a vertical dynamiccompression load to the test piece at a prescribed temperature and frequency. According to Hooke's law under a two-dimensional plane stress state of the split test, the present method deduces an analytical expression of the dynamic compression modulus and dynamic stretching modulus of the asphalt mixture, according to a relationship model between the dynamic compression modulus and the Poisson'sratio, through the method of simultaneously determination of the dynamic compression modulus, the dynamic stretching modulus and Poisson's ratio of the asphalt mixture, the method greatly improves test efficiency and accuracy, and is beneficial to further scientifically and reliably evaluate dynamic response characteristics of the asphalt mixture under the two-dimensional stress conditions, and has good application and promotion value.

Description

technical field

[0001] The invention belongs to the field of road engineering asphalt pavement, in particular to a method for synchronously testing dynamic compression, tensile modulus and Poisson's ratio of asphalt mixture. Background technique

[0002] The modulus and Poisson's ratio of asphalt mixture are the most important parameters in the mechanical analysis and structural design of asphalt pavement, and their values ​​will directly affect the structural response analysis, service performance evaluation and life prediction of asphalt pavement. my country's current "Code for Design of Highway Asphalt Pavement" (JTG D50-2017) is an elastic layered design system that assumes isotropy of pavement materials, and stipulates that the uniaxial dynamic compression modulus is used to characterize the asphalt mixture in all directions in the pavement structure. modulus state. Asphalt mixture is a heterogeneous and anisotropic material composed of mineral aggregates, asphalt and v...

Examples

Embodiment

[0070] Two kinds of asphalt mixtures, high modulus 30#-AC20 and common 70#-AC20, are selected. The corresponding asphalt types, mineral material gradation, optimal asphalt ratio and void ratio are shown in Table 1.

[0071] Table 1 Mixing ratio parameters of two kinds of AC20 asphalt mixture

[0072]

[0073] Determine the dynamic tensile modulus, dynamic compressive modulus and Poisson's ratio of the above two AC20 asphalt mixtures under different loading frequencies in the splitting test. The specific implementation steps are as follows:

[0074] (1) Preparation of split test pieces

[0075] In the test room, the asphalt mixture specimens with a diameter of 150mm and a height of 100mm were formed respectively according to the two kinds of AC20 asphalt mixture parameters in Table 1 through the asphalt mixture rotary compactor. Cut off 20 mm from both ends of the formed rotary compaction test piece to obtain a split test piece of asphalt mixture cylinder with a diameter of...

technical field

[0001] The invention belongs to the field of road engineering asphalt pavement, in particular to a method for synchronously testing dynamic compression, tensile modulus and Poisson's ratio of asphalt mixture. Background technique

[0002] The modulus and Poisson's ratio of asphalt mixture are the most important parameters in the mechanical analysis and structural design of asphalt pavement, and their values ​​will directly affect the structural response analysis, service performance evaluation and life prediction of asphalt pavement. my country's current "Code for Design of Highway Asphalt Pavement" (JTG D50-2017) is an elastic layered design system that assumes isotropy of pavement materials, and stipulates that the uniaxial dynamic compression modulus is used to characterize the asphalt mixture in all directions in the pavement structure. modulus state. Asphalt mixture is a heterogeneous and anisotropic material composed of mineral aggregates, asphalt and v...

Examples

Embodiment

[0070] Two kinds of asphalt mixtures, high modulus 30#-AC20 and common 70#-AC20, are selected. The corresponding asphalt types, mineral material gradation, optimal asphalt ratio and void ratio are shown in Table 1.

[0071] Table 1 Mixing ratio parameters of two kinds of AC20 asphalt mixture

[0072]

[0073] Determine the dynamic tensile modulus, dynamic compressive modulus and Poisson's ratio of the above two AC20 asphalt mixtures under different loading frequencies in the splitting test. The specific implementation steps are as follows:

[0074] (1) Preparation of split test pieces

[0075] In the test room, the asphalt mixture specimens with a diameter of 150mm and a height of 100mm were formed respectively according to the two kinds of AC20 asphalt mixture parameters in Table 1 through the asphalt mixture rotary compactor. Cut off 20 mm from both ends of the formed rotary compaction test piece to obtain a split test piece of asphalt mixture cylinder with a diameter of...

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