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The experiments on the structural mechanics of asphalt pavement were carried out by the digital speckle correlation method (DSCM). The digital speckle correlation method is used to collect experimental data. The displacement and strain values of each layer of the asphalt pavement structure are analyzed. The research showed that (1) the digital speckle correlation methods could accurately observe the displacement value and the strain value of the pavement structure. (2) The stress state of the pavement structure was greatly influenced by the interlayer effect. The vertical displacement changed suddenly between layers. The concentration phenomenon of the tension-compression strain and the shear strain appeared between layers. (3) The overloading situation seriously worsened the overall stress state of the pavement structure, especially at the bottom of the asphalt top layer and lower layer and at the top of the cement-stabilized crushed stone. The research results are of great significance to the structural design of heavy-duty roads.

The bearing characteristics of the asphalt pavement structure are greatly influenced by buried pipelines. Improper treatment of buried pipelines would cause early damage to pavement structure. By the digital speckle correlation method (DSCM), the experimental research on bearing characteristics of the asphalt pavement containing buried pipe was carried out. The mechanical characteristics of the asphalt pavement structure are studied under four different pipeline burial conditions. The vertical displacement and strain values of each layer of the asphalt pavement structure are obtained under four operating conditions. The results showed that (1) the digital speckle observation test method can accurately obtain the displacement and strain values of each layer of asphalt pavement structure containing buried pipeline, and the application effect is good. Compared with the traditional contact strain measurement method, this method is simple and accurate and can provide effective analysis data for experimental research. (2) There exists an interlayer effect of the asphalt pavement structure. The vertical displacement value and the strain value are discontinuities and can suddenly change between two adjacent layers. At the same time, the vertical strain and the shear strain concentration phenomenon appear at the bottom of each layer, especially at the bottom of the upper layer and the subbase layer of asphalt. (3) Affected by the buried pipelines, the vertical displacement value of the asphalt pavement structure reduces, and the tensile and shear strain values of asphalt pavement structure increase. The subbase layer of asphalt is most affected by the buried pipelines, which accelerated the destruction of the asphalt pavement structure.

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In order to study the rock fracture mechanism and precursor characteristics, uniaxial compression experiments of red sandstone were carried out. Using acoustic emission technology and digital speckle correlation method as experimental observation means, the evolution characteristics of deformation field and acoustic emission index during rock deformation were studied. The results show that : (1) The deformation concentration of rock deformation localization zone is the main cause of nonlinear evolution of rock stress-strain curve. (2) The volume parameters of different types of cracks in rock acoustic emission change with the relative displacement rate and dislocation rate of deformation localization zone. (3) In terms of failure types, there are more high-frequency components of tensile fracture main frequency, more low-frequency components of shear fracture main frequency, and wider distribution of mixed fracture main frequency. In the time sequence, the spectrum distribution of acoustic emission signals is wide and the amplitude is small at the sudden change time. At the sudden change time, the spectrum distribution of acoustic emission signals becomes narrow, the amplitude increases, and the spectrum distribution of peak points is greatly narrowed. Therefore, it is considered that the spectrum distribution is greatly narrowed can be used as an early warning precursor.