Study On The Stability Of Tailings Dam Based On Geofabriform Method

As a new technology to solve the problem of fine-grained tailings damming,the geofabriform method fills fine-grained tailings in the set of geotextile bags,by taking the distinct advantages of geofabriform material's permeability,sand fixation and accelerated consolidation,to achieve the fast and safe damming of fine-grained tailings.This method has arousing more and more concern and interest in the research field of fine-grained tailings damming.The technique of geofabriform method originates from the field of slope protection in the water sector,and a series of research results have already been formed and accumulated.In this paper,the technical achievements has been successfully applied to the field of tailings dam construction to develop the key technological innovation appropriately.According to the characteristics and requirements of tailings damming,the paper mainly studies the mechanism of stability and how to check the result focused particularly by the geofabriform method,the findings and results are summarized as follows.(1)On the basis of the geofabriform filling experiments of fine-grained tailings,the applicative range of particle size is explored and studied for fine-grained tailings dam on the geofabriform method.The result shows that the particle size from+0.074mm accounted for 10%?20%to-0.045mm about 70%of fine-grained tailings can be directly used to build the embankment by using the geofabriform method.Thus,it breaks through the limitation and restriction that the tailings within this particle size range cannot be built embankment directly.(2)It reveals the mechanism of strength enhancement of geofabriform embankment.The geofabriform bodies and mechanical characteristics among them are further researched and studied through the strength enhancement mechanism analysis and kinds of mechanical properties test of geofabriform bodies.The restriction effect of the tension from geotextile bag makes the geofabriform material and the tailings working holistically,which improves the shear strength obviously comparing to loose tailings and enhances its monolithic.The tailings change into the material of certain continuity from the granular material,therefore the safety factor of tailings dam is promoted by 25%.(3)The numerical simulation and analysis method of tailings dam built by the geofabriform method are established.The slope stability of the geofabriform method for tailings dam is verified and calibrated by means of horizontal slice division and the establishment of equilibrium equation.According to the characteristics that the failure mode of geofabriform embankment is mainly due to sliding among the bags,surface contact element is used to simulate the interlayer contact of geofabriform bodies,and finally the interlayer slip deformation and failure process of the geofabriform bodies are obtained through calculating and analyzing the characteristics of the interlayer slip failure based on the shear strength reduction method and interface finite element method.The above research and study results have been applied to the engineering practice of two tailings dam by using geofabriform method,which is proved effectively and achieves the objective.