Method and system for survey and stability evaluation of upstream tailing fill dam

A method for survey and stability evaluation of an upstream tailing fill dam, comprising the following steps:

• selecting a drill bit and a soil sampler for a target tailing fill dam;
• collecting tailing sand at different depths of the target tailing fill dam using the drill bit and the soil sampler;
• detecting an undisturbed soil sample of the tailing sand;
• setting a preset standard according to the undisturbed soil sample, and screening the tailing sand using the preset standard to obtain a tailing sand sample;
• detecting particle composition of the tailing sand sample, wherein the particle composition comprises the diameter size of particles forming the tailing sand and the number of particles of the tailing sand in different particle diameter ranges;
• detecting the mechanical property of the tailing sand sample, wherein the mechanical property comprises cohesion, friction strength and shear strength of the tailing sand sample;
• evaluating the stability of the target tailing fill dam through the particle composition and the mechanical property;
• wherein detecting an undisturbed soil sample of the tailing sand comprises the following steps:
• presetting the characteristics of the tailing sand according to the structure of the soil sampler, wherein the characteristics comprise a preset volume and a preset surface area of the tailing sand;
• using the characteristics to construct an initial undisturbed soil sample judging model;
• measuring the tailing sand to obtain a measured volume and a measured surface area;
• preliminarily judging the undisturbed soil sample of the tailing sand according to the measured volume, the measured surface area and the initial undisturbed soil sample judging model;
• measuring a volumetric strain of the tailing sand at different depths;
• using the volumetric strain of the tailing sand to fit a tailing sand volumetric strain-depth regression curve equation;
• judging the undisturbed soil sample of the tailing sand again using the tailing sand volumetric strain-depth regression curve equation;
• in which the initial undisturbed soil sample judging model satisfies the following formula:
• C=average(S′/S,V′/V),
• where C represents the degree of the initial undisturbed soil sample of the tailing sand, S′ represents the measured surface area of the tailing sand, S represents the preset surface area of the tailing sand, V′ represents the measured volume of the tailing sand, and V represents the preset volume of the tailing sand.