Evolution law and mechanism of tailings strength deterioration under the influence of capillary
;To study the influence law and mechanism of capillary action on the engineering properties of tailings dams,the mechanical properties of tailings at different distances from the outer slope of the stacked dam and the sedimentary beach in the natural water-bearing state,capillary saturation state and gravity saturation state were tested by direct shear test.The test results show that:(1)With the increase of moisture content,the cohesion gradually increases with the decrease of particle size,and the internal friction angle decreases with the decrease of particle size,and the two work together to affect its shear strength;(2)With the increase of moisture content,the strength of tailings gradually decreases;(3)In the direction from the head of the reservoir to the end of the reservoir,the particle size of the tailings gradually decreases,the porosity ratio between the particles increases,the height of capillary water rises gradually,and the moisture content of the tailings also increases.The moisture content of tailings in the capillary saturation state and the gravity saturation state were equal,which further indicated that the tailings'moisture content in the capillary saturation zone above the infiltration line was equal to the tailings'moisture content below the infiltration line;(4)The concept of capillary saturation zone is introduced,the concept and calculation method of the real infiltration line of tailings dam based on the influence of capillary action are proposed,and the calculation formula of the infiltration line height is corrected.It is suggested that the height of the infiltration line considering the influence of capillary action should be used in the stability evaluation of tailings dams,and the capillary water content index should be increased for monitoring dam water content.The results of this study provide basic data for disaster prevention and mitigation and early warning analysis of tailings ponds under hydraulic conditions.
safety engineeringtailings pond safetycapillarityshear strengthsaturation line
万方数据
维普
