The Research On Variable Scale Risk Assessment Method Of Tailings Dam Based On Multi-degradation Attribute Parameters

As one of the three controlling projects in mining resource exploitation,tailings dam is safe or not,which not only affects the economic development of society,but also is closely related to people’s life and property and natural environment.The characteristics of dam building materials and ways are of vital importance to the anti-slip stability of the dam body.Among them,the damming materials will gradually show the unstable phenomena such as cracks and desertification in the dam body due to rainfall and sun exposure,and the physical and mechanical properties of the material property parameters are the key elements that directly reflect the degradation of the materials.Also,the effect of the damming methods on the dam’s performance is reflected in the degradation of attribute parameters.With the growth of the operation time of tailings dam,the stability of the dam will show a decline due to the deterioration of internal property parameters,and the stability scale of the safety grade of tailings dam will be changed accordingly.If the stability scale fails to be adjusted according to the variation of the internal performance of dam,it may be possible to make a mistake in the safety grade of the dam when using external monitoring indicators for risk assessment.The problem on the surface is that the static stability scale is inconsistent with the degradation of dam body.In essence,it lacks the exploration of the linkage mechanism between the multi-degradation property parameters and the stability scale and the dynamic adjustment mechanism of the stability scale.Therefore,this paper studies the variable scale risk assessment methods of tailings dam based on multiple degradation property parameters,and the main research contents are as follows:(1)Quantitative description of the degradation performance of tailings dam:The characteristics of damming materials and the way of damming and the types of material property parameters are analyzed;The physical and mechanical properties of each attributeparameter are analyzed,and the parameter selection rules and methods that can reflect the performance degradation of the dam body and its effect on the stability of the dam body are investigated,and the valid attribute parameters are selected as the research variables;(2)The measurement and representation of attribute parameters:Based on the internal safety monitoring system of the dam and the previous failure accident of the dam,the set of attribute parameter information is constructed;The parameter information set is represented by the normal information diffusion method,and its optimal probability distribution is fitted;Based on the numerical characteristics and distribution of attribute parameter sets,the variation trend of each parameter is analyzed by using the man-kendall method;The probability distribution is constructed according to the variation range and characteristics of the property parameters;(3)Study on dynamic variation of stability scale:The correlation is analyzed between the attribute parameters and the stability,the collaborative mechanism is explored between multiple attribute parameters,the effect of the attribute parameter change on the stability of the dam body is analyzed,the correlation rules between attribute parameters and the stability are studied,different methods are adopted to establish the mapping relationship and made a comparative analysis;According to the optimal mapping function relation model,the stability scale after the dam performance degradation is determined;(4)The construction of risk assessment model based on variable scale function:Based on the determined stability scale,the set value mapping between the attribute parameter information set and the safety factor set is set by the possibility set value mapping;By intercepting the two sets and calculating the overlap length of the intercepting on the stability scale,the variable scale risk assessment model is constructed;In the case of a pine-tail-mining dam,a variable scale risk assessment model is used to analyze the stability of the dam;Results show that the stability scale in the variable-scale risk assessment model can be adjusted on the basis of the dam body attribute parameter degradation,which improves the monitoring and supervision ability of the safety monitoring system of mine enterprises,so as to effectively guarantee the safety production of mines.