A Speckle Making Method on the Surface of Saturated Rock Specimen Applied to Digital Speckle

Abstract

The invention discloses a speckle making method on the surface of a saturated rock specimen applied to a digital speckle correlation method. The invention changes the time sequence of making the speckle field, and when the rock specimen is initially saturated with water, it uses a fresh-keeping film or rubber The mold tightly wraps the rest of the surface except for the artificial speckle surface, and then sprays paint to make artificial speckle spots to prevent a large amount of water from evaporating during the speckle surface drying. After the speckle is completed, the plastic wrap or rubber mold is removed and the rock specimen is soaked in water to the natural saturation state again. Based on the fact that only a very small amount of gas is released from the rock body after the initial water saturation, the speckle surface will not lift up the surface due to the escape of gas during the second water saturation process, thereby ensuring the complete dispersion of the water-saturated rock. The speckle surface solves the problem of using the digital speckle correlation method to measure the strain field to create a complete speckle field for saturated rocks.

Description

technical field [0001] The invention relates to a speckle making method on the surface of a water-saturated rock test piece applied to a digital speckle correlation method, and belongs to the field of displacement field and strain field measurement in rock mechanics rock sample compression damage process. Background technique [0002] Rock is a heterogeneous material commonly used in large and complex projects such as water conservancy, roads, and underground mining. In the state of water, pores and micro-cracks become the main water-permeable channels, and the water flow fills the pores and micro-cracks. The existence of water softens the mechanical properties and stability of rocks. Over the years, due to the lack of understanding of the impact of water on the mechanical properties of rocks, many major engineering accidents have occurred in history, such as the 1864 accident of cracks and dam collapses in the Dale Dyke Reservoir in the United Kingdom, and the world's highe...

AI Technical Summary

Problems solved by technology

At present, the method of spraying paint is often used to make artificial speckle on the surface of the object, but for the saturated rock specimen, if the artificial speckle field is made before immersion, the gas in the pores will be excluded due to the water absorption in the specimen during the immersion process , the speckle surface of the specimen cannot be directly discharged due to the spraying of paint, so protruding bubbles will be generated, which will destroy the prepared speckle surface and cannot provide a complete artificial speckle scene; if the speckle spots are sprayed after being saturated with water , the water will evaporate a lot while waiting for the speckle field to dry, and the specimen cannot reach the saturated state

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