Stability Consider Seepage, Seismic Action Typical Of The Tailings Dam

Tailings at tailings dam generally contain heavy metal material, and if the tailings dam has break, it will cause casualties, environmental pollution and other serious consequences. Main causes of the tailings dam break are the seepage effect and earthquake effect, so the study about the typical tailings dam stability with a considerati on of seepage effect and earthquake effect has important theoretical and practical value. Taking the typical Zhelamujing tailing dam project as an example, this paper focuses on the typical seepage behavior and analyzes the stability of typical tailing dam subject to earthquake and seepage through scene investigations and a number of outdoor tests. The main researches conducted in this paper are as follows:1.Through a series of tests including on-the-spot investigation, experiments, sampling and indoor soil tests and indoor dynamic triaxial tests on Zhelamujing Tailing Dam, this paper researches in depth and systematically into physical and mechanical properties and also researches into the deposition law and seepage line characteristics of tailings.2. This paperstudies the calculation and evaluation methods of tailing dams’ stability, calculates and evaluates Zhelamujing Tailing Dam’s stability with and without taking the influence of seepage into account respectively by use of the limit equilibrium method, especially the Bishop method and Janbu method, researches into the influence of seepage force on tailing dams’stability and discusses influence factors of tailing dams’stability.3. This paper explains the basic theory of the coupling of the seepage field and the stress field of tailing dams, performs programming on the initial pore pressure of the tailing dam model by using the built-in FISH programming language in FLAC3D, and analyzes the seepage field numerical modeling of tailing dams. According to the distribution of pore pressure nephogram, location of the seepage line inside the tailing dam is obtained approximately, which is consistent with that of the measured seepage line during engineering investigation.This paper also researches into the coupling of the seepage field and stress field. Besides, it researches into the relationship between pore water pressure, effective stress, displacement field and seepage time step by using FLAC3D for numerical modeling analysis on the coupling of the seepage field and stress field of tailing dams.4. This paper introduces in detail the principle of discriminant methods for liquefaction potential of tailing dams such as standard penetration method, static cone penetration test method, shear wave velocity test method and shear stress contrast method, discriminates liquefaction potential of Zhelamujing Tailing Dam by using these methods, and according to the principle and discriminant results of each discriminant method, discusses the applicable conditions and precision of each discriminant method. Based on that, the paper puts forward the influence factors of tailing dams’liquefaction.5. This paper, by a test on the dynamic propertiesof tailings and analysis on the dynamic modulus damping test results, performs numerical modeling analysis on tailing dams’dynamic response by using FLAC3D software, researches into changes in dam deformation and pore pressure of tailing dams and reveals pore water pressure, effective stress, displacement time step curves and their interrelations.Through the above researches, the innovative research results obtained are as follows:1. the effects of seepage action in stability caculation of tailing dams were discussed, and the results shows that when the seepage line increases by lm, the stability factor Fs decreases by0.01-0.043or0.5%-2.6%; meanwhile, this paper also puts forward the sensitive relationship between physical and mechanical properties of tailing dams and safety coefficient.2. By numerical modeling analysis on the coupling of the seepage field and stressfield of tailing dams, this paper reveals the relationship between pore water pressure, effective stress, displacement field and seepage time step.this paper presents the idea that fluid-solid coupling is an important influence factor of tailing dams’ stability.3. By the evaluation research on tailing dams’stability, this paper suggests that seepage force must be taken in account while calculating tailing dams’stability and gives finite difference numerical modeling analysis calculation model for tailing dams’ stability when influence of fluid-solid coupling is considered. This opens new ways of thinking about the stability evaluation of tailing dams...