Method for inverting rock mineral parameters based on nano-indentation and numerical simulation

Abstract

The invention relates to the technical field of rock mineral mechanical parameter measurement and characterization, and aims to provide a method for inverting rock mineral parameters based on nano-indentation and numerical simulation. The method comprises the following steps: selecting different minerals on the surface of the rock to perform a nano-indentation test to obtain load-displacement curves, elastic modulus and hardness of different minerals; establishing a numerical model and a numerical test scheme based on a numerical simulation method, obtaining numerical simulation data for establishing an artificial neural network model, and obtaining a quantitative mapping relation after training and verification; and obtaining an optimal solution through an optimized search algorithm, namely the mechanical parameters of the rock minerals. By means of numerical simulation, the microscopic mechanical parameters of the minerals are associated with the nano-indentation test data, and the technical problem of parameter characterization of the rock minerals is solved; the accuracy and robustness of the artificial neural network model can be improved, and parameter characterization can berealized quickly and accurately; and the method for inverting rock mineral parameters based on nano-indentation and numerical simulation has the advantages of low cost, simple operation and high application and popularization values.

Description

technical field [0001] The invention belongs to the technical field of rock mineral mechanical parameter measurement and characterization, and in particular relates to a method for inverting physical and mechanical parameters of rock mineral composition based on nano-indentation test data and numerical simulation. Background technique [0002] On a mesoscopic scale, rocks are heterogeneous and anisotropic natural materials composed of various minerals. Different rock mineral types, cementation methods of mineral particles, and mesomechanical parameters lead to different elastic modulus and strength characteristics of various rocks. How to quantitatively analyze mineral composition, mesostructure, and the relationship between mineral mechanical parameters and rock macroscopic parameters, and explain the mesoscopic geomechanical mechanism of rock macroscopic mechanical behavior has always been a research hotspot in the academic and engineering circles at home and abroad. To s...

AI Technical Summary

Problems solved by technology

The difficulties of using nanoindentation test to test the physical and mechanical properties of rock mineral components are: (1) Rock is a natural multiphase material, and the structure of different minerals is complex, and the particle size variability is large, so it is difficult to test at the nanometer scale Accurate identification of specific minerals leads to large dispersion of test data; (2) Although the nanoindentation test can directly obtain the elastic modulus and hardness of minerals, it cannot directly obtain the strength parameters of minerals

[0004] Although some scholars have carried out research on the above problems, the existing methods generally estimate the strength parameters of materials through "trial and error" based on experience, and generally lack a method to accurately characterize the mechanical parameters of mineral components through nanoindentation tests. effective method

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