Research On Interfaction Behavior Between Coal Gangue And Geosynthetics

This thesis takes the coal gangue and polypropylene biaxially oriented geogrids(GSL40/PP) as the research object, first through using laboratory pull-out text ofcoal gangue and geogrid, study the interaction characteristics influencing rule of coalgangue and geogrid under overburden pressure, fine material of coal gangue andwater content three factors. The results showed: the maximum pulling force is linearincreased with the increase of the overburden pressure, The higher the overburdenpressure, the lower the interface similar coefficient of friction of coal gangue andgeogrid; with the increase of fine material, the maximum pulling force decrease, thesimilar cohesion first decrease and then increase, the similar friction always decrease;with the increase of water content, it is good or bad for Interface parameters isrelated to the fine material of coal gangue, under the same overburden pressure, ifthe fine material of coal gangue was22%, the maximum pulling force of geogridunder saturation is lower than under optimum water content; if the fine material ofcoal gangue was70%, the maximum pulling force of geogrid under saturation ishigher than under optimum water content.Then through FLAC3D numerical simulation experiment, compared with abovelaboratory test results. The experimental value of similar friction is consistent withnumerical simulation value, numerical simulation process can take experimentalvalue directly; the experimental value of similar cohesion is lower than numericalsimulation value, so should appropriatly increase the value of similar cohesion innumerical calculation, take three times the experimental values.Finally take Huainan mining area of a9.5km railway line as engineeringbackground, determine the reasonable interface parameters of coal gangue andgeogrid, use limit equilibrium method and strength reduction method to calculate thestability of coal gangue railway embankment before and after laying geogrid, safetyfactor improves46.37%和36.80%, the effect of laying geogrid is obvious.